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In JoVE (2)
- Reverse Yeast Two-hybrid System to Identify Mammalian Nuclear Receptor Residues that Interact with Ligands and/or Antagonists
- Using Microfluidic Devices to Measure Lifespan and Cellular Phenotypes in Single Budding Yeast Cells
Other Publications (200)
- PloS One
- The Cochrane Database of Systematic Reviews
- Food and Chemical Toxicology : an International Journal Published for the British Industrial Biological Research Association
- Learning & Memory (Cold Spring Harbor, N.Y.)
- Journal of the American Chemical Society
- Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi = Chinese Journal of Schistosomiasis Control
- Emerging Infectious Diseases
- Dental Materials : Official Publication of the Academy of Dental Materials
- Journal of Inflammation (London, England)
- Optics Express
- Medical Physics
- PloS One
- Zhongguo Zhen Jiu = Chinese Acupuncture & Moxibustion
- Critical Care (London, England)
- Journal of Bacteriology
- PloS One
- Journal of Immunology (Baltimore, Md. : 1950)
- Science (New York, N.Y.)
- Chemistry & Biology
- PloS One
- Nanoscale Research Letters
- Zhongguo Dang Dai Er Ke Za Zhi = Chinese Journal of Contemporary Pediatrics
- Nanoscale Research Letters
- Applied and Environmental Microbiology
- Optics Express
- Medical Physics
- Chinese Journal of Integrative Medicine
- Human Vaccines & Immunotherapeutics
- PloS One
- Archives of Medical Science : AMS
- Hua Xi Kou Qiang Yi Xue Za Zhi = Huaxi Kouqiang Yixue Zazhi = West China Journal of Stomatology
- Zhonghua Xue Ye Xue Za Zhi = Zhonghua Xueyexue Zazhi
- Sheng Li Ke Xue Jin Zhan [Progress in Physiology]
- Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi = Chinese Journal of Schistosomiasis Control
- Angewandte Chemie (International Ed. in English)
- European Archives of Oto-rhino-laryngology : Official Journal of the European Federation of Oto-Rhino-Laryngological Societies (EUFOS) : Affiliated with the German Society for Oto-Rhino-Laryngology - Head and Neck Surgery
- Plant, Cell & Environment
- Brain Research Bulletin
- Anti-cancer Agents in Medicinal Chemistry
- Journal of Integrative Plant Biology
- Journal of the American Chemical Society
- FEBS Letters
- Acta Biochimica Et Biophysica Sinica
- The Journal of Asthma : Official Journal of the Association for the Care of Asthma
- Food Chemistry
- Expert Opinion on Therapeutic Patents
- Analytical Chemistry
- Chemical Communications (Cambridge, England)
- Tumour Biology : the Journal of the International Society for Oncodevelopmental Biology and Medicine
- Oral Surgery, Oral Medicine, Oral Pathology and Oral Radiology
- Frontiers in Bioscience (Landmark Edition)
- Journal of Dermatological Science
- Virology Journal
- Journal of Oral and Maxillofacial Surgery : Official Journal of the American Association of Oral and Maxillofacial Surgeons
- Microbiological Research
- Food and Chemical Toxicology : an International Journal Published for the British Industrial Biological Research Association
- Journal of Clinical Neuroscience : Official Journal of the Neurosurgical Society of Australasia
- Neurological Research
- The Journal of Steroid Biochemistry and Molecular Biology
- Biosensors & Bioelectronics
- Chemical Communications (Cambridge, England)
- Emerging Infectious Diseases
- Science (New York, N.Y.)
- Cancer Epidemiology
- Schizophrenia Research
- Journal of Molecular Endocrinology
- Brain Research
- PLoS Neglected Tropical Diseases
- Medical Physics
- Current Eye Research
- European Journal of Orthopaedic Surgery & Traumatology : Orthopédie Traumatologie
- PloS One
- Cellular and Molecular Neurobiology
- Stroke; a Journal of Cerebral Circulation
- Infection, Genetics and Evolution : Journal of Molecular Epidemiology and Evolutionary Genetics in Infectious Diseases
- Life Sciences
- Neurology India
- Scientific Reports
- Cell Biochemistry and Biophysics
- Stroke; a Journal of Cerebral Circulation
- Regulatory Peptides
- International Journal of Molecular Sciences
- Proceedings of the National Academy of Sciences of the United States of America
- Surgical and Radiologic Anatomy : SRA
- Cell and Tissue Research
- Molecular Ecology
- Chemical Communications (Cambridge, England)
- Journal of Neurosurgical Anesthesiology
- Oral Surgery, Oral Medicine, Oral Pathology and Oral Radiology
- Neuroscience Research
- The Journal of Biological Chemistry
- Journal of Biomechanics
- European Journal of Cancer (Oxford, England : 1990)
- Journal of Immunology (Baltimore, Md. : 1950)
- Cell Biology International
- Biosensors & Bioelectronics
- Chemical Communications (Cambridge, England)
- Zhongguo Zhong Xi Yi Jie He Za Zhi Zhongguo Zhongxiyi Jiehe Zazhi = Chinese Journal of Integrated Traditional and Western Medicine / Zhongguo Zhong Xi Yi Jie He Xue Hui, Zhongguo Zhong Yi Yan Jiu Yuan Zhu Ban
- Biomedical Engineering Online
- Oncology Letters
- Annals of Biomedical Engineering
- BMJ Open
- Nucleic Acids Research
- Lab on a Chip
- American Journal of Human Genetics
- Neurosurgical Review
- Journal of the American Chemical Society
- AAPS PharmSciTech
- Chemical Communications (Cambridge, England)
- Muscle & Nerve
- PloS One
- Dalton Transactions (Cambridge, England : 2003)
- Virologica Sinica
- Sheng Wu Gong Cheng Xue Bao = Chinese Journal of Biotechnology
- Journal of Environmental Science and Health. Part A, Toxic/hazardous Substances & Environmental Engineering
- Biochemical and Biophysical Research Communications
- Yonsei Medical Journal
- Chemistry (Weinheim an Der Bergstrasse, Germany)
- Environmental Science & Technology
- Journal of Computational Neuroscience
- Virologica Sinica
- Brain Research Bulletin
- Fungal Genetics and Biology : FG & B
- Chinese Medical Journal
- Food Chemistry
- Cell Research
- The New England Journal of Medicine
- Arthritis and Rheumatism
- Proceedings of the National Academy of Sciences of the United States of America
- Acta Biochimica Et Biophysica Sinica
- Angewandte Chemie (International Ed. in English)
- Oncology Letters
- Rheumatology International
- Ticks and Tick-borne Diseases
- Cellular Immunology
- Tumour Biology : the Journal of the International Society for Oncodevelopmental Biology and Medicine
- Molecular Diversity
- Plant Physiology and Biochemistry : PPB / Société Française De Physiologie Végétale
- Health and Quality of Life Outcomes
- PLoS Neglected Tropical Diseases
- Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi = Chinese Journal of Otorhinolaryngology Head and Neck Surgery
- BMC Genomics
- Zhonghua Yi Xue Za Zhi
- PloS One
- Chemical Communications (Cambridge, England)
- PloS One
- The Journal of Chemical Physics
- Artificial Cells, Nanomedicine, and Biotechnology (Print)
- Clinical Infectious Diseases : an Official Publication of the Infectious Diseases Society of America
- Acta Biomaterialia
- International Journal of Nanomedicine
- Digestive Diseases and Sciences
- Neuroscience Bulletin
- Clinical Infectious Diseases : an Official Publication of the Infectious Diseases Society of America
- Canadian Journal of Microbiology
- Advanced Materials (Deerfield Beach, Fla.)
- The International Journal of Biochemistry & Cell Biology
- Chemical Communications (Cambridge, England)
- Journal of Hazardous Materials
- Pathology Oncology Research : POR
- Veterinary Parasitology
- Tumour Biology : the Journal of the International Society for Oncodevelopmental Biology and Medicine
- Digestive Surgery
- Journal of the American Chemical Society
- Tumour Biology : the Journal of the International Society for Oncodevelopmental Biology and Medicine
- Current Eye Research
- ACS Applied Materials & Interfaces
- Human Genetics
- PLoS Genetics
- Expert Opinion on Therapeutic Patents
- PloS One
- Clinical and Experimental Pharmacology & Physiology
- Acta Biochimica Et Biophysica Sinica
- Conference Proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference
- Chemistry, an Asian Journal
- The Spine Journal : Official Journal of the North American Spine Society
- International Journal of Pharmaceutics
- Current Eye Research
- Beijing Da Xue Xue Bao. Yi Xue Ban = Journal of Peking University. Health Sciences
- Journal of Food Science
- Proceedings of the National Academy of Sciences of the United States of America
- PloS One
- Organic Letters
- Biosensors & Bioelectronics
- Organic Letters
- Journal of the American Chemical Society
- Stroke; a Journal of Cerebral Circulation
- The Journal of Rheumatology
- Journal of Gastrointestinal Surgery : Official Journal of the Society for Surgery of the Alimentary Tract
- Preparative Biochemistry & Biotechnology
- Food Chemistry
Articles by Hao Li in JoVE
Reverse Yeast Two-hybrid System to Identify Mammalian Nuclear Receptor Residues that Interact with Ligands and/or Antagonists
Hao Li*1, Wei Dou*2, Emil Padikkala1, Sridhar Mani1
1Department of Genetics, Albert Einstein College of Medicine, 2Shanghai Key Laboratory of Complex Prescription and MOE Key Laboratory for Standardization of Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine
Using Microfluidic Devices to Measure Lifespan and Cellular Phenotypes in Single Budding Yeast Cells
Ke Zou1,2, Diana S. Ren2, Qi Ou-yang1,3, Hao Li2, Jiashun Zheng2
1The State Key Laboratory for Artificial Microstructures and Mesoscopic Physics, School of Physics, Peking University, 2Department of Biochemistry and Biophysics, University of California, San Francisco, 3Peking-Tsinghua Center for Life Sciences at Center for Quantitative Biology, Academy for Advanced Interdisciplinary Studies, Peking University
Other articles by Hao Li on PubMed
Association of MicroRNA-499 Rs3746444 Polymorphism with Cancer Risk: Evidence from 7188 Cases and 8548 Controls
PloS One. 2012 | Pubmed ID: 22970328
Owing to inconsistent and inconclusive results, we performed a meta-analysis to derive a more precise estimation of the association between miR-499 rs3746444 polymorphism and cancer risk.
The Cochrane Database of Systematic Reviews. 2012 | Pubmed ID: 22972139
Stroke is a serious public health problem that causes morbidity and mortality throughout the world. Iron chelators are potential neuroprotective drugs to treat patients with both hemorrhagic and ischemic stroke.
Food and Chemical Toxicology : an International Journal Published for the British Industrial Biological Research Association. Dec, 2012 | Pubmed ID: 22981909
Increasing interest in carnosic acid (CA) is due to its pharmacological properties. The aim of this study was to evaluate the acute and 30-day oral toxicity of CA.
Learning & Memory (Cold Spring Harbor, N.Y.). 2012 | Pubmed ID: 22988290
Reversal learning has been widely used to probe the implementation of cognitive flexibility in the brain. Previous studies in monkeys identified an essential role of the orbitofrontal cortex (OFC) in reversal learning. However, the underlying circuits and molecular mechanisms are poorly understood. Here, we use the T-maze to investigate the neural mechanism of olfactory reversal learning in Drosophila. By adding a reversal training cycle to the classical learning protocol, we show that wild-type flies are able to reverse their choice according to the alteration of conditioned stimulus (CS)-unconditioned stimulus (US) contingency. The reversal protocol induced a specific suppression of the initial memory, an effect distinct from memory decay or extinction. GABA down-regulation in the anterior paired lateral (APL) neurons, which innervate the mushroom bodies (MBs), eliminates this suppression effect and impairs normal reversal. These findings reveal that inhibitory regulation from the GABAergic APL neurons facilitates olfactory reversal learning by suppressing initial memory in Drosophila.
Journal of the American Chemical Society. Oct, 2012 | Pubmed ID: 23002805
The mechanism governing the redox-stimulated switching behavior of a tristable rotaxane consisting of a cyclobis(paraquat-p-phenylene) (CBPQT(4+)) ring encircling a dumbbell, containing tetrathiafulvalene (TTF) and 1,5-dioxynaphthalene (DNP) recognition units which are separated from each other along a polyether chain carrying 2,6-diisopropylphenyl stoppers by a 4,4'-bipyridinium (BIPY(2+)) unit, is described. The BIPY(2+) unit acts to increase the lifetime of the metastable state coconformation (MSCC) significantly by restricting the shuttling motion of the CBPQT(4+) ring to such an extent that the MSCC can be isolated in the solid state and is stable for weeks on end. As controls, the redox-induced mechanism of switching of two bistable rotaxanes and one bistable catenane composed of CBPQT(4+) rings encircling dumbbells or macrocyclic polyethers, respectively, that contain a BIPY(2+) unit with either a TTF or DNP unit, is investigated. Variable scan-rate cyclic voltammetry and digital simulations of the tristable and bistable rotaxanes and catenane reveal a mechanism which involves a bisradical state coconformation (BRCC) in which only one of the BIPY(•+) units in the CBPQT(2(•+)) ring is oxidized to the BIPY(2+) dication. This observation of the BRCC was further confirmed by theoretical calculations as well as by X-ray crystallography of the catenane in its bisradical tetracationic redox state. It is evident that the incorporation of a kinetic barrier between the donor recognition units in the tristable rotaxane can prolong the lifetime and stability of the MSCC, an observation which augurs well for the development of nonvolatile molecular flash memory devices.
[Screening and Verification on Characteristic Differentially Expressed Genes of Schistosoma Japonicum from Three Reservoir Hosts]
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi = Chinese Journal of Schistosomiasis Control. Jun, 2012 | Pubmed ID: 23012949
To get the characteristic differentially expressed genes of Schistosoma japonicum from three important reservoir hosts: yellow cattle, water buffalo and goat, so as to find the genetic markers to identify the various sources of the parasite reservoir hosts.
Emerging Infectious Diseases. Oct, 2012 | Pubmed ID: 23017728
To identify Candidatus Neoehrlichia mikurensis infection in northeastern China, we tested blood samples from 622 febrile patients. We identified in 7 infected patients and natural foci for this bacterium. Field surveys showed that 1.6% of ticks and 3.8% of rodents collected from residences of patients were also infected.
Effect of a Non-thermal, Atmospheric-pressure, Plasma Brush on Conversion of Model Self-etch Adhesive Formulations Compared to Conventional Photo-polymerization
Dental Materials : Official Publication of the Academy of Dental Materials. Dec, 2012 | Pubmed ID: 23018084
To determine the effectiveness and efficiency of non-thermal, atmospheric plasmas for inducing polymerization of model dental self-etch adhesives.
Journal of Inflammation (London, England). 2012 | Pubmed ID: 23033955
Optics Express. Aug, 2012 | Pubmed ID: 23038495
A processing method for the precise acquisition of 1D interference spectrum from the 2D Fabry-Pérot(F-P) fringe pattern is proposed in the paper. Current methods can only measure the spectrum with full-pixel accuracy. The new method is capable to achieve the sub-pixel accuracy as well as reduce the noise by taking full advantage of the 2D image information and analyzing the statistical values of pixels in a comprehensive way. Experimental results show that the accuracy of the measured Brillouin shift and linewidth is around several MHzs, which is significantly improved compared to methods with full-pixel accuracy.
Medical Physics. Oct, 2012 | Pubmed ID: 23039644
To implement dual-energy imaging technique for virtual monochromatic (VM) and linearly mixed (LM) cone beam CTs (CBCTs) and to demonstrate their potential applications in metal artifact reduction and contrast enhancement in image-guided radiation therapy (IGRT).
Metabolic Regulation of Trisporic Acid on Blakeslea Trispora Revealed by a GC-MS-based Metabolomic Approach
PloS One. 2012 | Pubmed ID: 23049952
The zygomycete Blakeslea trispora is used commercially as natural source of â-carotene. Trisporic acid (TA) is secreted from the mycelium of B. trispora during mating between heterothallic strains and is considered as a mediator of the regulation of mating processes and an enhancer of carotene biosynthesis. Gas chromatography-mass spectrometry and multivariate analysis were employed to investigate TA-associated intracellular biochemical changes in B. trispora. By principal component analysis, the differential metabolites discriminating the control groups from the TA-treated groups were found, which were also confirmed by the subsequent hierarchical cluster analysis. The results indicate that TA is a global regulator and its main effects at the metabolic level are reflected on the content changes in several fatty acids, carbohydrates, and amino acids. The carbon metabolism and fatty acids synthesis are sensitive to TA addition. Glycerol, glutamine, and ã-aminobutyrate might play important roles in the regulation of TA. Complemented by two-dimensional electrophoresis, the results indicate that the actions of TA at the metabolic level involve multiple metabolic processes, such as glycolysis and the bypass of the classical tricarboxylic acid cycle. These results reveal that the metabolomics strategy is a powerful tool to gain insight into the mechanism of a microorganism's cellular response to signal inducers at the metabolic level.
The Unfolded Protein Response in Fission Yeast Modulates Stability of Select MRNAs to Maintain Protein Homeostasis
ELife. 2012 | Pubmed ID: 23066505
The unfolded protein response (UPR) monitors the protein folding capacity of the endoplasmic reticulum (ER). In all organisms analyzed to date, the UPR drives transcriptional programs that allow cells to cope with ER stress. The non-conventional splicing of Hac1 (yeasts) and XBP1 (metazoans) mRNA, encoding orthologous UPR transcription activators, is conserved and dependent on Ire1, an ER membrane-resident kinase/endoribonuclease. We found that the fission yeast Schizosaccharomyces pombe lacks both a Hac1/XBP1 ortholog and a UPR-dependent-transcriptional-program. Instead, Ire1 initiates the selective decay of a subset of ER-localized-mRNAs that is required to survive ER stress. We identified Bip1 mRNA, encoding a major ER-chaperone, as the sole mRNA cleaved upon Ire1 activation that escapes decay. Instead, truncation of its 3' UTR, including loss of its polyA tail, stabilized Bip1 mRNA, resulting in increased Bip1 translation. Thus, S. pombe uses a universally conserved stress-sensing machinery in novel ways to maintain homeostasis in the ER.DOI:http://dx.doi.org/10.7554/eLife.00048.001.
[Comparative Observation on Therapeutic Effects Between Acupuncture and Western Medication for Diarrhea-predominant Irritable Bowel Syndrome]
Zhongguo Zhen Jiu = Chinese Acupuncture & Moxibustion. Aug, 2012 | Pubmed ID: 23072079
To compare the efficacy difference in diarrhea-predominant irritable bowel syndrome between acupuncture in terms of soothing liver and strengthening spleen and western medication.
Endothelin-receptor Antagonists for Aneurysmal Subarachnoid Hemorrhage: an Updated Meta-analysis of Randomized Controlled Trials
Critical Care (London, England). Oct, 2012 | Pubmed ID: 23078672
ABSTRACT: INTRODUCTION: The previous meta-analysis on the use of endothelin-receptor antagonists (ETRAs) to treat aneurysmal subarachnoid hemorrhage (SAH) has become outdated due to recently published phase 3 clinical trials. An up-to-date meta-analysis is needed to provide the best available evidence for the efficacy of ETRAs for aneurysmal SAH. METHODS: We performed a systematic review and meta-analysis of published randomized controlled trials that investigate efficacy of ETRAs in patients with aneurysmal SAH. Mortality, unfavorable outcome, delayed ischemic neurological deficit (DIND), delayed cerebral infarction (DCI), angiographic vasospasm and adverse events were analyzed. Meta-analysis was performed in terms of the risk ratio (RR) and 95% confidence interval (CI). RESULTS: Five eligible studies were reviewed and analyzed, involving 2,595 patients. The pooled RRs of mortality and unfavorable outcome after SAH were 1.03 (95% CI = 0.77 to 1.36) and 1.07 (95% CI = 0.93 to 1.22), respectively. The pooled RRs were 0.87 (95% CI = 0.74 to 1.03) for DCI, 0.77 (95% CI = 0.66 to 0.90) for DIND, and 0.66 (95% CI = 0.57 to 0.77) for angiographic vasospasm. There were significant increases in lung complications (RR = 1.80, 95% CI = 1.55 to 2.09), hypotension (RR = 2.42, 95% CI = 1.78 to 3.29) and anemia (RR = 1.47, 95% CI = 1.19 to 1.83) in patients administered ETRAs. CONCLUSION: There is no evidence that ETRAs could benefit clinical outcome in patients with SAH. Owing to the increased adverse events, further clinical trials of ETRAs in SAH patients should be more carefully formulated and designed. The present results also suggest that DCI may be a better outcome measure than vasospasm and DIND in SAH clinical trials and observational studies.
Journal of Bacteriology. Nov, 2012 | Pubmed ID: 23105078
Bartonella quintana is a re-emerging pathogen and the causative agent of a broad spectrum of disease manifestations in humans. The present study reports the complete genome of B. quintana strain RM_11, which was isolated from rhesus macaques.
Ultrastructural Observation and Gene Expression Profiling of Schistosoma Japonicum Derived from Two Natural Reservoir Hosts, Water Buffalo and Yellow Cattle
PloS One. 2012 | Pubmed ID: 23110087
Water buffalo and yellow cattle are the two of the most important natural reservoir hosts for Schistosoma japonicum in endemic areas of China, although their susceptibility differs, with water buffalo being less conducive to the growth and development of S. japonicum. Results from the current study show that the general morphology and ultrastructure of adult schistosomes derived from the two hosts also differed. Using high-throughput microarray technology, we also compared the gene expression profiles of adult schistosomes derived from the two hosts. We identified genes that were differentially expressed in worms from the two natural hosts. Further analysis revealed that genes associated with protein kinase and phosphatase, the stimulus response, and lipid and nucleotide metabolism were overexpressed, whereas genes associated with reproduction, anatomical structure morphogenesis and multifunctional motif were underexpressed in schistosomes from water buffalo. These differentially expressed genes were mainly involved in nucleotide, energy, lipid metabolism, energy metabolism, transcription, transport and signaling pathway. This suggests that they are key molecules affecting the survival and development of schistosomes in different natural host species. The results of this study add to current understanding of the interplay between parasites and their natural hosts, and provide valuable information for the screening of vaccine candidates or new drug targets against schistosomiasis in the natural reservoir hosts in endemic areas.
Nonalloreactive T Cells Prevent Donor Lymphocyte Infusion-induced Graft-versus-host Disease by Controlling Microbial Stimuli
Journal of Immunology (Baltimore, Md. : 1950). Dec, 2012 | Pubmed ID: 23136200
In mice, graft-versus-host reactions, associated with powerful graft-versus-tumor effects, can be achieved without graft-versus-host disease (GVHD) by delayed administration of donor lymphocyte infusions (DLI) to established mixed chimeras. However, GVHD sometimes occurs after DLI in established mixed chimeric patients. In contrast to mice, in which T cell recovery from the thymus occurs prior to DLI administration, human T cell reconstitution following T cell-depleted hematopoietic cell transplantation is slow, resulting in lymphopenia at the time of DLI. We demonstrate in this study that T cell lymphopenia is an independent risk factor for GVHD following DLI in the absence of known inflammatory stimuli. DLI-induced GVHD was prevented in lymphopenic recipients by prior administration of a small number of nonalloreactive polyclonal T cells, insufficient to prevent lymphopenia-associated expansion of subsequently administered T cells, through a regulatory T cell-independent mechanism. GVHD was not inhibited by T cells with irrelevant specificity. Moreover, administration of antibiotics reduced the severity of GVHD in lymphopenic hosts. Accumulation of DLI-derived effector T cells and host hematopoietic cell elimination were markedly diminished by regulatory T cell-depleted, nonalloreactive T cells. Finally, thymectomized mixed chimeras showed increased GVHD following delayed DLI. Collectively, our data demonstrate that in the absence of known conditioning-induced inflammatory stimuli, T cell lymphopenia is a risk factor for GVHD in mixed chimeras receiving delayed DLI. Our data suggest that the predisposition to GVHD can at least in part be explained by the presence of occult inflammatory stimuli due to the absence of T cells to control microbial infections.
Science (New York, N.Y.). Nov, 2012 | Pubmed ID: 23139336
Mitochondria must grow with the growing cell to ensure proper cellular physiology and inheritance upon division. We measured the physical size of mitochondrial networks in budding yeast and found that mitochondrial network size increased with increasing cell size and that this scaling relation occurred primarily in the bud. The mitochondria-to-cell size ratio continually decreased in aging mothers over successive generations. However, regardless of the mother's age or mitochondrial content, all buds attained the same average ratio. Thus, yeast populations achieve a stable scaling relation between mitochondrial content and cell size despite asymmetry in inheritance.
Validation of the Proteasome As a Therapeutic Target in Plasmodium Using an Epoxyketone Inhibitor with Parasite-specific Toxicity
Chemistry & Biology. Dec, 2012 | Pubmed ID: 23142757
The Plasmodium proteasome has been suggested to be a potential antimalarial drug target; however, toxicity of inhibitors has prevented validation of this enzyme in vivo. We report a screen of a library of 670 analogs of the recent US Food and Drug Administration-approved inhibitor, carfilzomib, to identify compounds that selectively kill parasites. We identified one compound, PR3, that has significant parasite killing activity in vitro but dramatically reduced toxicity in host cells. We found that this parasite-specific toxicity is not due to selective targeting of the Plasmodium proteasome over the host proteasome, but instead is due to a lack of activity against one of the human proteasome subunits. Subsequently, we used PR3 to significantly reduce parasite load in Plasmodium berghei infected mice without host toxicity, thus validating the proteasome as a viable antimalarial drug target.
PloS One. 2012 | Pubmed ID: 23144860
A major limitation to yeast aging study has been the inability to track mother cells and observe molecular markers during the aging process. The traditional lifespan assay relies on manual micro-manipulation to remove daughter cells from the mother, which is laborious, time consuming, and does not allow long term tracking with high resolution microscopy. Recently, we have developed a microfluidic system capable of retaining mother cells in the microfluidic chambers while removing daughter cells automatically, making it possible to observe fluorescent reporters in single cells throughout their lifespan. Here we report the development of a new generation of microfluidic device that overcomes several limitations of the previous system, making it easier to fabricate and operate, and allowing functions not possible with the previous design. The basic unit of the device consists of microfluidic channels with pensile columns that can physically trap the mother cells while allowing the removal of daughter cells automatically by the flow of the fresh media. The whole microfluidic device contains multiple independent units operating in parallel, allowing simultaneous analysis of multiple strains. Using this system, we have reproduced the lifespan curves for the known long and short-lived mutants, demonstrating the power of the device for automated lifespan measurement. Following fluorescent reporters in single mother cells throughout their lifespan, we discovered a surprising change of expression of the translation elongation factor TEF2 during aging, suggesting altered translational control in aged mother cells. Utilizing the capability of the new device to trap mother-daughter pairs, we analyzed mother-daughter inheritance and found age dependent asymmetric partitioning of a general stress response reporter between mother and daughter cells.
Radial N-i-p Structure SiNW-based Microcrystalline Silicon Thin-film Solar Cells on Flexible Stainless Steel
Nanoscale Research Letters. 2012 | Pubmed ID: 23146105
Radial n-i-p structure silicon nanowire (SiNW)-based microcrystalline silicon thin-film solar cells on stainless steel foil was fabricated by plasma-enhanced chemical vapor deposition. The SiNW solar cell displays very low optical reflectance (approximately 15% on average) over a broad range of wavelengths (400 to 1,100 nm). The initial SiNW-based microcrystalline (μc-Si:H) thin-film solar cell has an open-circuit voltage of 0.37 V, short-circuit current density of 13.36 mA/cm2, fill factor of 0.3, and conversion efficiency of 1.48%. After acid treatment, the performance of the modified SiNW-based μc-Si:H thin-film solar cell has been improved remarkably with an open-circuit voltage of 0.48 V, short-circuit current density of 13.42 mA/cm2, fill factor of 0.35, and conversion efficiency of 2.25%. The external quantum efficiency measurements show that the external quantum efficiency response of SiNW solar cells is improved greatly in the wavelength range of 630 to 900 nm compared to the corresponding planar film solar cells.
Zhongguo Dang Dai Er Ke Za Zhi = Chinese Journal of Contemporary Pediatrics. Nov, 2012 | Pubmed ID: 23146735
To investigate the mutation of glucose-6-phosphatase gene (G6PC gene) in a patient with glycogen storage disease Ⅰa.
Plasmonic Enhancements of Photoluminescence in Hybrid Si Nanostructures with Au Fabricated by Fully Top-down Lithography
Nanoscale Research Letters. 2012 | Pubmed ID: 23158215
The authors study plasmonic enhancements of photoluminescence (PL) in Si nanodisk (ND) arrays hybridized with nanostructures such as nanoplates of Au, where these hybrid nanostructures are fabricated by fully top-down lithography: neutral-beam etching using bio-nano-templates and high-resolution electron-beam lithography. The separation distance between the Si ND and Au nanostructure surfaces is precisely controlled by inserting a thin SiO2 layer with a thickness of 3 nm. We observe that PL intensities in the Si NDs are enhanced by factors up to 5 depending on the wavelength by integrating with the Au nanoplates. These enhancements also depend on the size and shape of the Au nanoplates.
Strip-based Immunoassay for the Simultaneous Detection of the Neonicotinoid Insecticides Imidacloprid and Thiamethoxam in Agricultural Products
Talanta. Nov, 2012 | Pubmed ID: 23158295
A semiquantitative strip immunoassay was developed for the rapid detection of imidacloprid and thiamethoxam in agricultural products using specific nanocolloidal gold-labeled monoclonal antibodies. The conjugates of imidacloprid-BSA, thiamethoxam-BSA and goat anti-mouse IgG were coated on the nitro-cellulose membrane of the strip, serving as test lines and control line, respectively. The flow of the complexes of gold labeled antibodies and insecticides along the strip resulted in intensive color formed on the test lines inversely proportional to the concentrations of imidacloprid and thiamethoxam. The visual detection limits of imidacloprid and thiamethoxam in assay buffer were 0.5 and 2 ng mL(-1), respectively. Matrix interference of cucumber, tomato, lettuce, apple, and orange on the strip assay could be eliminated by diluting sample extracts with assay buffer. The strip analysis of imidacloprid and thiamethoxam in these samples was compared to liquid chromatography-mass spectrometry and the results were in good agreement. The strip was stable for storage more than 5 months at 4 °C. The strip assay is a rapid and simple method for the simultaneous screening of imidacloprid and thiamethoxam in agricultural products.
Applied and Environmental Microbiology. Nov, 2012 | Pubmed ID: 23183973
Candidatus Neoehrlichia mikurensis was detected by PCR in 4.0% (34/841) of the rodents. The 34 rodents represented nine species from seven regions of China. Phylogenetic analyses based on partial groEL and nearly entire 16S rRNA gene sequences of the agent revealed genetic diversity, which was correlated with its geographic origins.
Optics Express. Oct, 2012 | Pubmed ID: 23187179
All-optically controlled nanoparticle manipulating units based on optical waveguide intersections are designed and their performance on nanoparticle trapping, redirecting, sorting and binding force measurement are theoretically analyzed. Our calculation shows that these simple units have trapping abilities comparable with most near field trapping tools and are capable of realizing multiple sorting and analyzing functions.
Medical Physics. Dec, 2012 | Pubmed ID: 23231319
Cone-beam x-ray imaging with flat panel detectors is used for target localization in image guided radiation therapy. This imaging includes cone-beam computed tomography (CBCT) and planar imaging. Use of two orthogonal x-ray systems could reduce imaging time for CBCT, provide simultaneous orthogonal views in planar imaging, facilitate dual-energy methods, and be useful in alleviating cone-beam artifacts by providing two axially offset focal-spot trajectories. However, the potential advantages of a second cone-beam system come at the cost of cross scatter, i.e., scatter of photons originating from one tube into the noncorresponding detector. Herein, cross scatter is characterized for dual cone-beam imaging, and a method for avoiding cross scatter is proposed and evaluated.
Synergism Between Carnosic Acid and Arsenic Trioxide on Induction of Acute Myeloid Leukemia Cell Apoptosis is Associated with Modulation of PTEN/Akt Signaling Pathway
Chinese Journal of Integrative Medicine. Dec, 2012 | Pubmed ID: 23239002
To investigate the synergistic effects of carnosic acid (CA) with arsenic trioxide (As₂O₃) on proliferation and apoptosis in HL-60 human myeloid leukemia cells, and the major cellular signaling pathway involved in these effects.
Potential Impact of the Bivalent RLP2806 Vaccine on Neisseria Meningitidis Carriage and Invasive Serogroup B Disease
Human Vaccines & Immunotherapeutics. Dec, 2012 | Pubmed ID: 23249817
Asymptomatic throat carriage of Neisseria meningitidis is common in healthy individuals. In unusual cases, the bacteria become invasive, resulting in life-threatening disease. Effective meningococcal serogroup B (MnB) vaccines should provide broad protection against disease-causing strains and may confer indirect protection by impacting carriage and subsequent transmission. Factor H binding proteins (fHBPs), components of MnB vaccines in development, are classified into two immunologically distinct subfamilies (A and B). fHBP variants of MnB strains carried by adolescents are similar to those detected in infants with MnB disease. A vaccine containing subfamily A and B fHBP variants elicited bactericidal antibody responses (titers ≥ 1:4) against MnB strains expressing fHBP variants common to carriage strains and strains that cause disease in adolescents and infants in 75-100% of adolescent study subjects. This suggests that the bivalent fHBP vaccine has the potential to provide protection against invasive MnB strains and interrupt meningococcal carriage, which may also reduce infant MnB disease.
PloS One. 2012 | Pubmed ID: 23272213
Coxsackieviruses A10 (CV-A10) and A6 (CV-A6) have been associated with increasingly occurred sporadic hand-foot-mouth disease (HFMD) cases and outbreak events globally. However, our understanding of epidemiological and genetic characteristics of these new agents remains far from complete. This study was to explore the circulation of CV-A10 and CV-A6 in HFMD and their genetic characteristics in China. A hospital based surveillance was performed in three heavily inflicted regions with HFMD from March 2009 to August 2011. Feces samples were collected from children with clinical diagnosis of HFMD. The detection and genotyping of enteroviruses was performed by real-time PCR and sequencing of 5'UTR/VP1 regions. Phylogenetic analysis and selection pressure were performed based on the VP1 sequences. Logistic regression model was used to identify the effect of predominant enterovirus serotypes in causing severe HFMD. The results showed 92.0% of 1748 feces samples were detected positive for enterovirus, with the most frequently presented serotypes as EV-71 (944, 54.0%) and CV-A16 (451, 25.8%). CV-A10 and CV-A6 were detected as a sole pathogen in 82 (4.7%) and 44 (2.5%) cases, respectively. Infection with CV-A10 and EV-71 were independently associated with high risk of severe HFMD (OR = 2.66, 95% CI: 1.40-5.06; OR = 4.81, 95% CI: 3.07-7.53), when adjusted for age and sex. Phylogenetic analysis revealed that distinct geographic and temporal origins correlated with the gene clusters based on VP1 sequences. An overall ω value of the VP1 was 0.046 for CV-A10 and 0.047 for CV-A6, and no positively selected site was detected in VP1 of both CV-A10 and CV-A6, indicating that purifying selection shaped the evolution of CV-A10 and CV-A6. Our study demonstrates variety of enterovirus genotypes as viral pathogens in causing HFMD in China. CV-A10 and CV-A6 were co-circulating together with EV-71 and CV-A16 in recent years. CV-A10 infection might also be independently associated with severe HFMD.
Archives of Medical Science : AMS. Dec, 2012 | Pubmed ID: 23319966
To systematically review the relationship between low pH in intervertebral discs and low back pain.
[Affect of Protein Tyrosine Phosphatase Non-receptor Type 2 and Nuclear Factor-kappaB on Periodontal Destruction with Diabetes]
Hua Xi Kou Qiang Yi Xue Za Zhi = Huaxi Kouqiang Yixue Zazhi = West China Journal of Stomatology. Dec, 2012 | Pubmed ID: 23330368
To investigate the expression of protein tyrosine phosphatase non-receptor type 2 (PTPN2) and nuclear factor-kappaB (NF-kappaB), as well as the relationship between their expression and periodontal destruction in mice with diabetic periodontitis.
Zhonghua Xue Ye Xue Za Zhi = Zhonghua Xueyexue Zazhi. Dec, 2012 | Pubmed ID: 23363793
This study was aimed to analyze the relationship between single nucleotide polymorphisms of transforming growth factor-β1 G-800A and C-509T, interleukin-4 receptor V75I and susceptibility of CHL in adults.
Sheng Li Ke Xue Jin Zhan [Progress in Physiology]. Dec, 2012 | Pubmed ID: 23520762
[Longitudinal Observation of Epidemic Dynamics of Schistosomiasis in Bovine in Two Mountainous Endemic Regions]
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi = Chinese Journal of Schistosomiasis Control. Dec, 2012 | Pubmed ID: 23593833
To understand the endemic situation dynamics of schistosomiasis in domestic animals (mainly bovine) in mountainous endemic regions, so as to provide the reference for evaluating the control effect and improving control strategy.
Angewandte Chemie (International Ed. in English). Jan, 2013 | Pubmed ID: 22976927
In one fell swoop, polyrotaxanes comprising up to 64 rings can be synthesized as a result of cucurbituril-templated 1,3-dipolar azide-alkyne cycloadditions accelerated in the presence of cyclodextrins as a consequence of self-sorting and positive cooperativity, brought about by hydrogen bonding. Mixing six components in one pot affords a heterorotaxane in one minute in quantitative yield.
European Archives of Oto-rhino-laryngology : Official Journal of the European Federation of Oto-Rhino-Laryngological Societies (EUFOS) : Affiliated with the German Society for Oto-Rhino-Laryngology - Head and Neck Surgery. Mar, 2013 | Pubmed ID: 22986414
This study aimed to evaluate the value of using a linear stapler device in total laryngectomy using a prospective study. Twenty-one total laryngectomies were performed from August 2010 to April 2012, using TA-60 linear stapler for pharyngeal closure. Data collected included age, sex, staging, surgical margins and postoperative course (including complications and swallowing). Patients comprised twenty men and one woman. The mean age was 64 years. Two patients underwent preoperative radiotherapy. Four patients recurred after radiotherapy. Fifteen patients were untreated. Negative surgical margins were achieved in all patients. One patient developed slight pharyngocutaneous fistula. Patients resumed oral intake at 7 days. The mean hospital stay was 10 days. Using a linear stapler to close laryngopharyngeal cavity in total laryngectomy is simple, reliable and practical, avoids pollution of surgical area, saves operation time and decreases the incidence of pharyngocutaneous fistula. It is worthy of clinical application for selected cases.
Unravelling Mitochondrial Retrograde Regulation in the Abiotic Stress Induction of Rice ALTERNATIVE OXIDASE 1 Genes
Plant, Cell & Environment. Apr, 2013 | Pubmed ID: 22994594
Mitochondrial retrograde regulation (MRR) is the transduction of mitochondrial signals to mediate nuclear gene expression. It is not clear whether MRR is a common regulation mechanism in plant abiotic stress response. In this study, we analysed the early abiotic stress response of the rice OsAOX1 genes, and the induction of OsAOX1a and OsAOX1b (OsAOX1a/b) was selected as a working model for the stress-induced MRR studies. We found that the induction mediated by the superoxide ion (O2·(-) )-generating chemical methyl viologen was stronger than that of hydrogen peroxide (H2 O2 ). The addition of reactive oxygen species (ROS) scavengers demonstrated that the stress induction was reduced by eliminating O2·(-) . Furthermore, the stress induction did not rely on chloroplast- or cytosol-derived O2·(-) . Next, we generated transgenic plants overexpressing the superoxide dismutase (SOD) gene at different subcellular locations. The results suggest that only the mitochondrial SOD, OsMSD, attenuated the stress induction of OsAOX1a/b specifically. Therefore, our findings demonstrate that abiotic stress initiates the MRR on OsAOX1a/b and that mitochondrial O2·(-) is involved in the process.
Alterations in Tyrosine Kinase Receptor (Trk) Expression Induced by Insulin-like Growth Factor-1 in Cultured Dorsal Root Ganglion Neurons
Brain Research Bulletin. Jan, 2013 | Pubmed ID: 23022575
Insulin-like growth factor-1 (IGF-1) is a neurotrophic factor expressed in small dorsal root ganglion (DRG) neurons. IGF-1 promotes neuronal survival by activating its receptor (IGF-1R). Whether IGF-1 and its signaling pathways influence the expression of tyrosine kinase receptors TrkA, TrkB and TrkC in DRG neurons remains unknown. In the present study, primary cultured DRG neurons were used to determine the effects of IGF-1 on TrkA, TrkB and TrkC expression. The involvement of extracellular signal-regulated protein kinase (ERK1/2) and the effects of phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathways on IGF-1 were also evaluated. DRG neurons were cultured for 48h and then exposed to IGF-1, PD98059 plus IGF-1, LY294002 plus IGF-1, and PD98059 plus LY294002 plus IGF-1 for an additional 24h. The DRG neurons were continuously exposed to culture medium as a control. All cultures were then processed for detection of mRNA levels of TrkA, TrkB and TrkC using real-time PCR analysis. Protein levels of TrkA, TrkB and TrkC were detected using a Western blot assay. The expression of TrkA, TrkB and TrkC in situ was determined by a fluorescent labeling technique. The levels of phosphorylated ERK1/2 (pERK1/2) and phosphorylated Akt (pAkt) were detected using a Western blot assay. The results indicated that in primary cultured DRG neurons, IGF-1 increased the expression of TrkA and TrkB and their mRNAs but not TrkC or its mRNA. Neither the ERK1/2 inhibitor PD98059 nor the PI3K inhibitor LY294002 alone blocked the effect of IGF-1, but the use of both inhibitors together was effective. IGF-1 may play an important role in regulating the expression of different Trk receptors in DRG neurons through the ERK1/2 and PI3K/Akt signaling pathways. These results suggest that IGF-1 signaling might be a potential target on modifying distinct Trk receptor-mediated biological effects.
The Sorption of Organic Contaminants on Biochars Derived from Sediments with High Organic Carbon Content
Chemosphere. Jan, 2013 | Pubmed ID: 23089389
Biochars were produced using a Dianchi Lake sediment at different temperatures and their sorption characteristics with five organic contaminants (with solubilities varied three orders of magnitude) were compared. Freundlich model showed satisfying fitting results of the sorption isotherms. Distinct decrease of nonlinear factors was observed for all five contaminants with pyrolysis suggesting wider energy distribution of the sorption sites after pyrolysis. No clear trend was observed between K(d) and the chemical properties of the five chemicals. Phenanthrene and sulfamethoxazole (SMX) showed increased sorption with increased pyrolysis temperature, while the sorption of bisphenol A (BPA), ofloxacin (OFL) and norfloxacin (NOR) in the original sediment was comparable to those in the thermally treated samples. Electrostatic repulsion played an important role in SMX sorption as suggested by its lowest hydrophobicity-normalized sorption coefficients among the five chemicals. Possible sorption mechanisms were discussed and the sorption of SMX and PHE on the produced biochars were compared with natural adsorbents (including soils, sediments, and inorganic mineral particles).
Anti-cancer Agents in Medicinal Chemistry. Mar, 2013 | Pubmed ID: 23092268
Microbubbles (MBs) are gas-filled hollow microparticles. Under the ultrasound field, the difference of acoustic characteristics between gas and plasma in the blood vessel will cause strong impedance mismatch and echogenicity to enhance ultrasonic grey scale imaging. The linear or nonlinear resonance of MB shell in the ultrasound field would lead to repeated expansion-contraction till destruction. In this case, the pre-loaded drug in the MB shell will be released in an accelerated manner triggered by the ultrasound at a probe-given site. Sonoporation effect of the cell membrane would also help increase the uptake of substances into cells. This paper is dedicated to review recent developments on MBs, especially multifunctionalized MBs, as a potential drug/gene delivery microdevices for both diagnosis and therapy of malignant tumors.
Journal of Integrative Plant Biology. Feb, 2013 | Pubmed ID: 23116154
Abscisic acid (ABA) is a major plant hormone that plays an important role in responses to abiotic stresses. The ABA-responsive element binding protein/ABRE-binding factor (AREB/ABF) gene subfamily contains crucial transcription factors in the ABA-mediated signaling pathway. In this study, a total of 14 putative AREB/ABF members were identified in the Populus trichocarpa Torr. & Gray. genome using five AREB/ABF amino acid sequences from Arabidopsis thaliana L. as probes. The 14 putative Populus subfamily members showed high protein similarities, especially in the basic leucine zipper (bZIP) domain region. A neighbor-joining analysis combined with gene structure data revealed homology among the 14 genes. The expression patterns of the Populus AREB/ABF subfamily suggested that the most abundant transcripts of 11 genes occurred in leaf tissues, while two genes were most transcribed in root tissues. Significantly, eight Populus AREB/ABF gene members were upregulated after treatment with 100 μM exogenous ABA, while the other six members were downregulated. We identified the expression profiles of the subfamily members in Populus tissues and elucidated different response patterns of Populus AREB/ABF members to ABA stress. This study provided insight into the roles of Populus AREB/ABF homologues in plant response to abiotic stresses.
25-hydroxyvitamin D3 Ameliorates Periodontitis by Modulating the Expression of Inflammation-associated Factors in Diabetic Mice
Steroids. Feb, 2013 | Pubmed ID: 23138030
Periodontitis is a complication of diabetes mellitus, and the two diseases are highly associated with the dysfunction of inflammatory mediators. 25-hydroxyvitamin D(3) (25(OH)D(3)) plays a pivotal role in inflammatory modulation, but little is known about its effects on the progression of diabetic periodontitis and the underlying mechanism. In this paper, we showed that 25(OH)D(3) ameliorated experimental periodontitis in diabetic mice. The intraperitoneal administration of 25(OH)D(3) to streptozotocin-induced diabetic mice reduced fasting glucose and serum TNF-α levels, leading to decreased alveolar bone loss. Western blot analyses of gingival epithelia showed that vitamin D receptor (VDR) and protein tyrosine phosphatase N2 (PTPN2) were upregulated, while the expression of NF-κB and the phosphorylation of Janus family kinase 1 (JAK1) were attenuated upon 25(OH)D(3) treatment. These data may provide an explanation for the therapeutic benefits and anti-inflammatory effects of 25(OH)D(3). Our findings should have important implications for the clinical therapy of diabetic periodontitis.
Journal of the American Chemical Society. Jan, 2013 | Pubmed ID: 23163704
A homologous series of rotaxanes, in which cyclobis(paraquat-p-phenylene) (CBPQT(4+)) serves as the ring component, while the dumbbell components all contain single 4,4'-bipyridinium (BIPY(2+)) units centrally located in the midst of oligomethylene chains of varying lengths, have been synthesized by taking advantage of radical templation and copper-free azide-alkyne 1,3-dipolar cycloadditions in the formation of their stoppers. Cyclic voltammetry, UV/vis spectroscopy, and mass spectrometry reveal that the BIPY(•+) radical cations in this series of rotaxanes are stabilized against oxidation, both electrochemically and by atmospheric oxygen. The enforced proximity between the BIPY(2+) units in the ring and dumbbell components gives rise to enhanced Coulombic repulsion, destabilizing the ground-state co-conformations of the fully oxidized forms of these rotaxanes. The smallest rotaxane, with only three methylene groups on each side of its dumbbell component, is found to exist under ambient conditions in a monoradical state, a situation which does not persist in acetonitrile solution, at least in the case of its longer analogues. (1)H NMR spectroscopy reveals that the activation energy barriers to the shuttling of the CBPQT(4+) rings over the BIPY(2+) units in the dumbbells increase linearly with increasing oligomethylene chain lengths across the series of rotaxanes. These findings provide a new way of producing highly stabilized BIPY(•+) radical cations and open up more opportunities to use stable organic radicals as building blocks for the construction of paramagnetic materials and conductive molecular electronic devices.
FEBS Letters. Jan, 2013 | Pubmed ID: 23178712
MicroRNAs (miRNA) have emerged as key players in carcinogenesis. Here, we investigated the role of miR-137 in the pathogenesis of lung cancer. The downregulation of miR-137 in lung cancer cells could be rescued following inhibition of DNA methylation. Ectopic expression of miR-137 in lung cancer cells significantly downregulated Cdc42, Cdk6 and induced G1 cell cycle arrest, leading to a significant decrease in cell growth in vivo and in vitro. Further, both Cdc42 and Cdk6 were confirmed as targets of miR-137.
MiR-137 Restoration Sensitizes Multidrug-resistant MCF-7/ADM Cells to Anticancer Agents by Targeting YB-1
Acta Biochimica Et Biophysica Sinica. Feb, 2013 | Pubmed ID: 23178914
Multidrug resistance (MDR) to chemotherapeutic agents is a major obstacle to successful treatment in breast cancer patients. The aims of this study were to investigate whether miR-137 was involved in the regulation of MDR, and to explore the mechanism of miR-137 on the sensitivity of MCF-7/ADM cells. miR-137 was downregulated in MCF-7/ADM cells, and its expression was found to inversely correlate with Y-box binding protein-1 (YB-1) and P-glycoprotein (P-gp) levels in breast cancer cells. Furthermore, YB-1 was confirmed as a target of miR-137 by luciferase reporter assay and western blot analysis. Moreover, elevated expression of miR-137 reduced the protein expression levels of YB-1 and P-gp, mimicking the effect of YB-1 knockdown in the sensitivity of MCF-7/ADM cells to anticancer agents, whereas restoration of YB-1 diminished this effect. In conclusion, our results demonstrated that miR-137 was involved in MDR in cancer through modulation of P-gp by targeting YB-1, suggesting that miR-137 might be a potential target for preventing and reversing MDR in tumor cells.
The Journal of Asthma : Official Journal of the Association for the Care of Asthma. Feb, 2013 | Pubmed ID: 23190377
Asthma exacerbations are influenced by multiple factors including environmental exposures, psychosocial interactions, and genetic variations.
Food Chemistry. Feb, 2013 | Pubmed ID: 23194551
A semiquantitative dip strip assay was developed using nanocolloidal gold-labelled monoclonal antibody (Mab) 8A10 for the rapid detection of Sudan red I in food samples. A protein-Sudan red I conjugate was coated on a nitro cellulose membrane strip in a defined test line. In flow of the complex of nanocolloidal gold labelled-Mab and Sudan red I along the strip, intensive red colour that was formed in the test line reflected the Sudan red I concentration. The test required 10 min and had a visual limit of detection of 10 ng/g Sudan red I in tomato sauce and chilli powder samples. The results of the strip assay agreed well with those of a high performance liquid chromatography method for both spiked and real commercial samples. The strip was stable for at least 2 months at 4°C. The strip assay offers the potential as a useful rapid and simple method for screening of Sudan red I in food samples.
Expert Opinion on Therapeutic Patents. Jan, 2013 | Pubmed ID: 23205582
H(+)/K(+)-ATPase is a P-type ATP-driven cation transporter which exchanges ions (protons, chloride ions, and potassium ions) across the cell membrane. Modulators of H(+)/K(+)-ATPase affect H(+)/K(+) exchange.
Analytical Chemistry. Jan, 2013 | Pubmed ID: 23237077
Protein-binding peptide is recently recognized as an effective artificial affinity reagent for protein assays. However, its application is hampered by the limited choices of available signal readout methods. Herein, we report a general electrochemical signal readout method for protein-binding peptides exploiting the host-guest chemistry of cucurbituril. Via the formation of supermolecules among cucurbituril, electrochemical reporter, and the peptide, a protein-binding peptide can be noncovalently coupled with the electrochemical reporter. To assay the target protein, the protein-binding peptides are first self-assembled in the sensing layer, and after the capturing of the target protein, a portion of the peptides become protein-bound. The protein-free peptides are then coupled with the electrochemical reporter to yield a signal readout inversely proportional to the amount of the captured target proteins. Since the only requirement of supermolecule formation is the incorporation of aromatic amino acids in the peptide sequence, this strategy is universally applicable to many protein-binding peptides. The generality and target specificity of the proposed method are successfully demonstrated in the assays of two kinds of target proteins: tumor necrosis factor-α and amyloid β 1-42 soluble oligomer, respectively. The feasibility of our method is also tested in the monitoring of tumor necrosis factor-α secretion activity of HL-60 cells. These results indicate that our method can have great use in protein detection in the future.
Quinine-thiourea Catalyzed Enantioselective Hydrophosphonylation of Trifluoromethyl 2(1H)-quinazolinones
Chemical Communications (Cambridge, England). Jan, 2013 | Pubmed ID: 23248060
An organocatalytic enantioselective addition reaction of cyclic ketoimines with phosphites has been developed for the first time. The process, catalyzed by Soós' quinine thiourea, affords synthetically and medicinally interesting enantioenriched trifluoromethyl dihydroquinazolinones in high yields and with high enantioselectivities.
Tumour Biology : the Journal of the International Society for Oncodevelopmental Biology and Medicine. Apr, 2013 | Pubmed ID: 23264087
We aimed to investigate the expression of microRNA-34a (miR-34a) in human gastric cancer cells and to evaluate the effects of miR-34a, acting via its gene survivin, on gastric cancer cell HGC-27 to provide potential new strategies for treating gastric cancer. In vitro cultures of the human gastric cancer cell lines MGC80-3, HGC-27, NCI-N87, and SGC-7901 and the normal human gastric epithelial cell line GES-1 were established. The expression of miR-34a in each gastric cancer cell line and GES-1 normal human gastric epithelial cell line was detected using quantitative real-time polymerase chain reaction (qRT-PCR). After the HGC-27 cells were transfected with a miR-34a mimic for 48 h, the changes in the expression levels of miR-34a were detected using qRT-PCR. The effect of miR-34a on HGC-27 cell viability was measured using a tetrazolium-based colorimetric [-(4,5)-dimethylthiahiazo-(-z-y1)-3,5-di-phenytetrazoliumromide (MTT)] assay. Flow cytometry was used to analyze the effects of miR-34a on HGC-27 cell proliferation. Annexin V/propidium iodide double staining and flow cytometry were used to analyze the effects of miR-34a on HGC-27 cell apoptosis. A Transwell invasion chamber was used to detect the effects of miR-34a on HGC-27 cell invasion. Finally, western blotting was used to analyze the effects of miR-34a on survivin protein expression. The qRT-PCR test determined that miR-34a expression in gastric cancer cells was significantly reduced compared to the normal gastric epithelial cell line GES-1 (p < 0.01). Compared to the control group, cellular miR-34a expression levels were significantly increased in HGC-27 human gastric carcinoma cells after transfection with a miR-34a mimic for 48 h (p < 0.01). The MTT assay demonstrated that after overexpressing miR-34a in HGC-27 cells, cellular viability was significantly reduced (p < 0.05). Flow cytometry analysis determined that upon miR-34a overexpression, the proliferation index decreased significantly (p < 0.05), and cellular apoptosis was significantly increased (p < 0.01). The Transwell invasion chamber assay illustrated that after increasing the expression of miR-34a, the number of cells passing through the Transwell chamber was significantly reduced (p < 0.01). Based on western blotting, compared with the control group, survivin protein expression levels were significantly decreased in the HGC-27 cells transfected with the miR-34a mimic for 48 h (p < 0.01). In conclusion, the expression level of miR-34a was downregulated in human gastric cancer cell lines. miR-34a can negatively regulate survivin protein expression and inhibit gastric cancer cell proliferation and invasion. Therapeutically enhancing miR-34a expression or silencing the survivin gene may benefit patients with gastric cancer.
Influence of Pathologic Complete Response to Neoadjuvant Chemotherapy on Long-term Survival of Patients with Advanced Head and Neck Squamous Cell Carcinoma
Oral Surgery, Oral Medicine, Oral Pathology and Oral Radiology. Feb, 2013 | Pubmed ID: 23265986
The aim of this study was to analyze whether pathologic complete response (PCR) to neoadjuvant chemotherapy (NAC) affected long-term survival in advanced head and neck squamous cell carcinoma (HNSCC) patients.
Frontiers in Bioscience (Landmark Edition). 2013 | Pubmed ID: 23276929
Liver transplantation (LT) has emerged as a viable therapy for various end-stage liver diseases. Multi-drug resistant Gram-negative bacilli (MDR-GNB) have emerged as predominant pathogens. The prevalence of MDR-GNB infection has been increasing in LT recipients, especially in early post-LT stages. MDR-GNB infection has become a main cause of death following LT. Since key elements of MDR-GNB infection after LT mainly include the pre-LT severity of underlying disease, technical problems, acute rejection, and so on, appropriate measures, such as improvement of LT technology and management, restriction of antibiotic use and immunosuppressive therapy advancement, should be commenced to prevent and control the occurrence of MDR-GNB infection. A better understanding of the prevalence of and risk factors for MDR-GNB infection complications is needed to improve quality of life and survival rate after LT.
Inhibition of Farnesoid X Receptor Controls Esophageal Cancer Cell Growth in Vitro and in Nude Mouse Xenografts
Cancer. Apr, 2013 | Pubmed ID: 23280144
Gastroesophageal reflux is a risk factor for esophageal adenocarcinoma, and bile acid and its farnesoid X receptor (FXR) have been implicated in esophageal tumorigenesis. The authors investigated the role of FXR expression and activity in esophageal cancer initiation and growth.
Interactions Between FATP4 and Ichthyin in Epidermal Lipid Processing May Provide Clues to the Pathogenesis of Autosomal Recessive Congenital Ichthyosis
Journal of Dermatological Science. Mar, 2013 | Pubmed ID: 23290633
Autosomal recessive congenital ichthyosis (ARCI) is caused by mutations in ≥10 different genes, of which transglutaminase-1 (TGM1) predominates. A rare form is ichthyosis prematurity syndrome (IPS) caused by mutations in SLC27A4 encoding fatty acid transporter protein 4 (FATP4), believed to be an acyl-CoA synthetase activating long- and very-long-chain FA. Another ARCI is caused by mutations in NIPAL4, coding for ichthyin, which is proposed to be a magnesium transporter or a trans-membrane receptor. A possible interaction between FATP4 and ichthyin has not been studied before.
Virology Journal. 2013 | Pubmed ID: 23294868
While the function of the phosphoprotein (P) gene of the rabies virus (RABV) has been well studied in laboratory adapted RABVs, the genetic diversity and evolution characteristics of the P gene of street RABVs remain unclear. The objective of the present study was to investigate the mutation and evolution of P genes in Chinese street RABVs.
Journal of Oral and Maxillofacial Surgery : Official Journal of the American Association of Oral and Maxillofacial Surgeons. May, 2013 | Pubmed ID: 23298806
The purpose of this study was to assess the clinical application and therapeutic efficacy of through-and-through cheek defects reconstructed with folded anterolateral thigh (ALT) flaps.
Construction of a Gentamicin C1a-overproducing Strain of Micromonospora Purpurea by Inactivation of the GacD Gene
Microbiological Research. Jun, 2013 | Pubmed ID: 23305768
Gentamicin C1a is the precursor of the semi-synthetic antibiotic etimicin and has the highest antibacterial activity in the clinically important gentamicin C mixture. To obtain a gentamicin C1a-overproducing strain, we inactivated gacD gene in Micromonospora purpurea. The gacD was presumed to encode a C6' methyltransferase by sequence analysis, and plays a role in the conversion of the gentamicin intermediate X2 to G418. So the inactivation of gacD blocks the metabolic pathways from X2 to G418 and leads to the accumulation of gentamicin C1a.The resulting recombination strain produced gentamicin C1a more than 10-fold compared to the wild type strain. Moreover, the wild-type strain produced 4 main production components, C1a, C2, C2a and C1, while the recombination strain produced only 2 components, C1a and C2b, making the purification of gentamicin C1a easier. The recombination strain was genetically stable and should be useful for the industrial production of gentamicin C1a.
Neuroprotective Effects of Resveratrol on Embryonic Dorsal Root Ganglion Neurons with Neurotoxicity Induced by Ethanol
Food and Chemical Toxicology : an International Journal Published for the British Industrial Biological Research Association. May, 2013 | Pubmed ID: 23313797
Studies have established that ethanol (EtOH) consumption results in damage to the peripheral nervous systems. Although the pathobiological mechanism is still unclear, oxidative stress is known to play an important role in EtOH-induced neurotoxicity. Because resveratrol (Res) is attracting increased attention due to its antioxidative properties, we investigated the neuroprotective efficacy of Res in ethanol-treated embryonic dorsal root ganglion (DRG) neurons in vitro. Organotypic DRG explants and a dispersed cell culture model were used to evaluate the effects of Res on EtOH-induced neurotoxicity. Res increased the number of extended nerve fibers and neurons that migrated from the DRG explants. Hoechst 33342 staining and terminal deoxynucleotidyl-transferase-mediated dUTP nick-end-labeling analysis showed that the EtOH-induced apoptosis was inhibited by Res. The effects of Res were blocked by the 5'-adenosine monophosphate-activated protein kinase inhibitor Compound C and the sirtuin 1 inhibitor nicotinamide. The elevation of oxidative/nitrosative stress, as measured by the amount of reactive oxygen species, malondialdehyde, nitrite, glutathione and superoxide dismutase activity, was also attenuated by Res. The data from the present study indicate that Res protects DRG neurons from EtOH-induced neurotoxicity. Res and its derivative may be effective for the treatment of diseases characterized by axonopathy and neuron loss induced by EtOH.
Seasonal Variation in Spontaneous Intracerebral Hemorrhage Frequency in Chengdu, China, is Independent of Conventional Risk Factors
Journal of Clinical Neuroscience : Official Journal of the Neurosurgical Society of Australasia. Apr, 2013 | Pubmed ID: 23317754
Seasonal variations in the incidence of intracerebral hemorrhage (ICH) have been extensively evaluated in studies conducted in various parts of the world. However, seasonal variation of ICH in China has not been comprehensively reported in the English literature. The aim of the present study was to examine the seasonal variation of spontaneous ICH incidence and the 28-day case-fatality rate in a Chinese population. We also examined whether this variation was modified by conventional stroke risk factors (hypertension, diabetes mellitus, smoking, drinking alcohol). From 2006 to 2009, 1615 hemorrhagic stroke events (male, 965; female, 650) were registered in residents of the Jinjiang and Wuhou districts, Chengdu, China. Seasonal variation was calculated for the whole period. Incidence rates (per 100,000 person-seasons) and 95% confidence intervals (CI) were calculated by gender and age for winter, spring, summer, and autumn. After stratifying patients by their risk factor history, odds ratios and 95% CI of having a stroke in autumn, winter, and spring were calculated, with summer serving as a reference. Among the seasons, the incidence per 100,000 person-years of spontaneous cerebral hemorrhage was highest in the winter (45.5, 95% CI, 38.4-52.7) and lowest in summer (24.1, 95% CI, 21.9-26.2). Winter incidence was highest in both men and women, and in subjects younger than 60years as well as subjects 60years or older. The winter excess in stroke incidence was observed regardless of the presence or absence of risk factors. Factors that explain this excess need further investigation.
Persistence of Secondary Prevention Medications After Acute Ischemic Stroke or Transient Ischemic Attack in Chinese Population: Data from China National Stroke Registry
Neurological Research. Jan, 2013 | Pubmed ID: 23317796
Although proven stroke secondary prevention medications are available, persistent use is required to be effective. The present study aimed to investigate the degree of secondary prevention medications persistence after acute ischemic stroke (AIS) or transient ischemic attack (TIA), factors influencing persistence and its association with stroke outcomes.
25-Hydroxyvitamin D3 Attenuates Experimental Periodontitis Through Downregulation of TLR4 and JAK1/STAT3 Signaling in Diabetic Mice
The Journal of Steroid Biochemistry and Molecular Biology. May, 2013 | Pubmed ID: 23333931
Vitamin D has been known to be closely associated with diabetes and periodontitis while the underlying mechanism has yet to be clarified. The present study aimed to discover the effect of 25-hydroxyvitamin D3 (25-OHD3) on glycemic control and periodontal health in mice with periodontitis superimposed on experimental diabetes (known as diabetic periodontitis). We showed that 25-OHD3 intraperitoneal injection attenuated diabetic periodontitis by reducing serum fasting blood glucose, glycosylated hemoglobin and TNF-α levels, which led to decreased alveolar bone loss. Immunohistochemical staining and western blot analysis of gingival epithelia revealed that vitamin D receptor (VDR) expression was enhanced upon 25-OHD3 treatment, while toll-like receptor 4 (TLR4) expression was reduced. The expressions of Janus family kinase (JAK) 1 and signal transducer and activator of transcription (STAT) 3 as well as their phosphorylation were inhibited in gingival epithelia of diabetic periodontitis mice, whereas the expression and phosphorylation of STAT1 remained unchanged. These results suggest that 25-OHD3 could improve diabetic periodontitis through downregulation of TLR4 and JAK1/STAT3 signaling in the gingival epithelium. Our study extends the previous findings on the regulation of diabetes with periodontitis, and may also provide a potential therapy for the patients with this disease.
A Microfluidic System Enabling Continuous Characterization of Specific Membrane Capacitance and Cytoplasm Conductivity of Single Cells in Suspension
Biosensors & Bioelectronics. May, 2013 | Pubmed ID: 23337259
This paper presents a microfluidic system enabling continuous characterization of specific membrane capacitance (Cspecific membrane) and cytoplasm conductivity (σcytoplasm) of single cells in suspension. In this study, cells were aspirated continuously through a constriction channel while cell elongations and impedance profiles at two frequencies (1kHz and 100kHz) were measured simultaneously using microscopy imaging and a lock-in amplifier. 1kHz impedance data were used to evaluate cellular sealing properties with constriction channel walls and 100kHz impedance data were translated to quantify equivalent membrane capacitance and cytoplasm resistance of single cells, which were further translated to Cspecific membrane and σcytoplasm. Two model cell lines (kidney tumor cell line of 786-O (n=302) and vascular smooth muscle cell line of T2 (n=216)) were used to evaluate this technique, producing Cspecific membrane of 3.67±1.00 and 4.53±1.51μF/cm(2) and σcytoplasm of 0.47±0.09 and 0.55±0.14S/m, respectively. Compared to previously reported techniques which can only collect Cspecific membrane and σcytoplasm from tens of cells, this new technique has a higher throughput, capable of collecting Cspecific membrane and σcytoplasm from hundreds of cells in 30min immediately after cell passage.
Magnetic-field-induced Deposition to Fabricate Multifunctional Nanostructured Co, Ni, and CoNi Alloy Films As Catalysts, Ferromagnetic and Superhydrophobic Materials
Chemical Communications (Cambridge, England). Feb, 2013 | Pubmed ID: 23340666
A novel and facile magnetic-field-induced deposition process was put forward to fabricate nanostructured Co, Ni and CoNi alloy films supported on Cu foil, which are multifunctional nanomaterials with wide applications in different areas due to their ferromagnetic and superhydrophobic properties, as well as their excellent catalytic performance.
Emerging Infectious Diseases. Feb, 2013 | Pubmed ID: 23347418
We detected Bartonella quintana in 48.6% of captive rhesus macaques from an animal facility in Beijing, China. Prevalence of infection increased over the period of observation. Our findings suggest that macaques may serve as reservoir hosts for B. quintana and that Pedicinus obtusus lice might act as efficient vectors.
Science (New York, N.Y.). Jan, 2013 | Pubmed ID: 23349286
Most organic radicals possess short lifetimes and quickly undergo dimerization or oxidation. Here, we report on the synthesis by radical templation of a class of air- and water-stable organic radicals, trapped within a homocatenane composed of two rigid and fixed cyclobis(paraquat-p-phenylene) rings. The highly energetic octacationic homocatenane, which is capable of accepting up to eight electrons, can be configured reversibly, both chemically and electrochemically, between each one of six experimentally accessible redox states (0, 2+, 4+, 6+, 7+, and 8+) from within the total of nine states evaluated by quantum mechanical methods. All six of the observable redox states have been identified by electrochemical techniques, three (4+, 6+, and 7+) have been characterized by x-ray crystallography, four (4+, 6+, 7+, and 8+) by electron paramagnetic resonance spectroscopy, one (7+) by superconducting quantum interference device magnetometry, and one (8+) by nuclear magnetic resonance spectroscopy.
Cancer Epidemiology. Jun, 2013 | Pubmed ID: 23352629
To assess the effect of metformin intake on cancer incidence and mortality.
A Randomized Controlled Trial of Olanzapine Improving Memory Deficits in Han Chinese Patients with First-episode Schizophrenia
Schizophrenia Research. Mar, 2013 | Pubmed ID: 23352776
Olanzapine is an atypical antipsychotic for the treatment of schizophrenia, in which memory impairment is a core deficit. The methods of positive and negative syndrome scale (PANSS), Wechsler memory scale-4th edition (WMS-IV) and event-related potential (ERP) were used to study the effects of olanzapine on the cognitive function in the first-episode schizophrenic patients. We performed multicentre, randomized, double-blind, placebo-controlled, parallel-group clinical trial to study the cognitive functioning in Han Chinese first-episode schizophrenic patients in a 12-week treatment regime with olanzapine (129 cases) or placebo (132 cases). The results showed that (1) the patients with first-episode schizophrenia showed significant deficits in the long-term memory, short-term memory, immediate memory and memory quotient by WMS-IV assessment, and decreases the total scores, positive symptoms, negative symptoms and general psychopathology by PANSS assessment; (2) olanzapine could significantly improve the PANSS scores including total scores, positive symptoms, negative symptoms and general psychopathology in the first-episode schizophrenic patients; (3) olanzapine could significantly improve the short-term memory, immediate memory and memory quotient in the first-episode schizophrenic patients; and (3) although the latencies of P(2), N(2) and P(3) were significantly prolonged, P(2) and P(3) amplitudes were decreased and the latencies of N(1) did not change, olanzapine did not influence any P(300) items in the first-episode schizophrenic patients. The data suggested that that olanzapine could improve cognitive process, such as memorizing and extraction of the information although there were many changes of cognitive functions in Han Chinese first-episode schizophrenic patients.
The Role of the Renin-angiotensin-aldosterone System in Preeclampsia: Genetic Polymorphisms and MicroRNA
Journal of Molecular Endocrinology. Apr, 2013 | Pubmed ID: 23369849
The compensatory alterations in the rennin-angiotensin-aldosterone system (RAAS) contribute to the salt-water balance and sufficient placental perfusion for the subsequent well-being of the mother and fetus during normal pregnancy and is characterized by an increase in almost all the components of RAAS. Preeclampsia, however, breaks homeostasis and leads to a disturbance of this delicate equilibrium in RAAS both for circulation and the uteroplacental unit. Despite being a major cause for maternal and neonatal morbidity and mortality, the pathogenesis of preeclampsia remains elusive, where RAAS has been long considered to be involved. Epidemiological studies have indicated that preeclampsia is a multifactorial disease with a strong familial predisposition regardless of variations in ethnic, socioeconomic, and geographic features. The heritable allelic variations, especially the genetic polymorphisms in RAAS, could be the foundation for the genetics of preeclampsia and hence are related to the development of preeclampsia. Furthermore, at a posttranscriptional level, miRNA can interact with the targeted site within the 3'-UTR of the RAAS gene and thereby might participate in the regulation of RAAS and the pathology of preeclampsia. In this review, we discuss the recent achievements of genetic polymorphisms, as well as the interactions between maternal and fetal genotypes, and miRNA posttranscriptional regulation associated with RAAS in preeclampsia. The results are controversial but utterly inspiring and attractive in terms of potential prognostic significance. Although many studies suggest positive associations with genetic mutations and increased risk for preeclampsia, more meticulously designed large-scale investigations are needed to avoid the interference from different variations.
Cortical Electrical Stimulation Promotes Neuronal Plasticity in the Peri-ischemic Cortex and Contralesional Anterior Horn of Cervical Spinal Cord in a Rat Model of Focal Cerebral Ischemia
Brain Research. Apr, 2013 | Pubmed ID: 23370004
This study evaluated the effect of cortical electrical stimulation (CES) on function recovery, dendritic plasticity, astrogliosis, and neuron recruitment in the peri-ischemic cortex (PIC) and contralesional anterior horn of cervical spinal cord (CSC) in a rat model of focal cerebral ischemia. Materials and methods: Rats were pre-trained on single pellet retrieval task, then received focal ischemic lesions and electrodes implantation. Seven days after surgery, rats received CES (CES group) or no stimulation (NS group) during 18 days of training. Behavior data on stimulation days 2, 4, 6, 8, 10, 12, 14, 16 and 18 were pooled for use. Immunohistochemical investigations for microtubule-associated protein 2 (MAP-2), glial fibrillary acidic protein (GFAP) and neuronal nuclei antigen (NeuN) were performed. Results: Rats in CES group showed greater functional recovery of the impaired forelimb compared to the NS group. Moreover, the functional improvement coincided with a significant increase in MAP-2-immunoreactive dendritic surface density in PIC and CSC (P=0.011; P=0.005, respectively). CES group had a significant decrease in GFAP-immunoreactive astrocytic surface density in PIC and CSC (P=0.039; P=0.013, respectively). In the immunoassaying of NeuN, there was no significant difference between the two groups in PIC and CSC (P=0.834, P=0.782, respectively). Conclusion: CES can promote dendritic plasticity and reduce astrogliosis in the PIC and CSC in a rat model of focal cerebral ischemia. CES is still an appealing method for post-stroke rehabilitation provided that viability of pathways is evaluated presurgically.
National Borders Effectively Halt the Spread of Rabies: the Current Rabies Epidemic in China is Dislocated from Cases in Neighboring Countries
PLoS Neglected Tropical Diseases. 2013 | Pubmed ID: 23383359
China has seen a massive resurgence of rabies cases in the last 15 years with more than 25,000 human fatalities. Initial cases were reported in the southwest but are now reported in almost every province. There have been several phylogenetic investigations into the origin and spread of the virus within China but few reports investigating the impact of the epidemic on neighboring countries. We therefore collected nucleoprotein sequences from China and South East Asia and investigated their phylogenetic and phylogeographic relationship. Our results indicate that within South East Asia, isolates mainly cluster according to their geographic origin. We found evidence of sporadic exchange of strains between neighboring countries, but it appears that the major strain responsible for the current Chinese epidemic has not been exported. This suggests that national geographical boundaries and border controls are effective at halting the spread of rabies from China into adjacent regions. We further investigated the geographic structure of Chinese sequences and found that the current epidemic is dominated by variant strains that were likely present at low levels in previous domestic epidemics. We also identified epidemiological linkages between high incidence provinces consistent with observations based on surveillance data from human rabies cases.
Medical Physics. Feb, 2013 | Pubmed ID: 23387760
The purpose of this study is to evaluate the performance of a recently developed benchtop dual cone-beam computed tomography (CBCT) system with two orthogonally placed tube∕detector sets.
Comparison of Intravitreal Triamcinolone Acetonide with Intravitreal Bevacizumab for Treatment of Diabetic Macular Edema: a Meta-analysis
Current Eye Research. May, 2013 | Pubmed ID: 23405978
To compare the effects of intravitreal triamcinolone acetonide (IVTA) and intravitreal bevacizumab (IVB) injections for the treatment of diabetic macular edema (DME).
Prevention of Early Bone Loss Around the Prosthesis by Administration of Anti-osteoporotic Agents and Influences of Collared and Non-collared Femoral Stem Prostheses on Early Periprosthetic Bone Loss
European Journal of Orthopaedic Surgery & Traumatology : Orthopédie Traumatologie. Jul, 2013 | Pubmed ID: 23412167
The current study aims to investigate the effect of anti-osteoporotic agents of collared and non-collared femoral stem prostheses on periprosthetic bone mineral density (BMD) after total hip arthroplasty (THA). 80 patients who received THA due to femur neck subcapital fractures were involved. The treatment groups were given fosamax, caltrate D and Xianlinggubao for oral administration, whereas the control groups were only given caltrate D. BMD at the greater trochiter around the femoral stem prosthesis and at the femoral shaft 1.5-1.0 cm away from the distal femoral stem was tested using dual-energy X-ray absorptiometry (DEXA) scan. Meanwhile, BMD at the same sites on the uninjured side was also tested. The BMD at both sites in all groups decreased after implantation. In the collared groups, no significant difference was shown between the injured and uninjured sides at 12 days or 3 months (p > 0.001). At 6 months after implantation, significant differences were displayed at both sites between the treatment and control groups (p < 0.001). In the non-collared groups, significant differences were displayed at both sites between the treatment and control groups at 6-months postimplantation (p < 0.001). No significant difference showed between the collared and non-collared groups show any at either site on either side (p > 0.05). DEXA scan can quantitatively determine bone loss around the prosthesis after THA. BMD around the prosthesis is correlated with administration of anti-osteoporotic agents. Fosamax + caltrate D + Xianlinggubao can prevent early bone loss around the prosthesis.
Gender Differences in 1-year Clinical Characteristics and Outcomes After Stroke: Results from the China National Stroke Registry
PloS One. 2013 | Pubmed ID: 23418571
Previous reports have shown inconsistent results on clinical outcomes between women and men after stroke, and little is known about gender differences on outcomes in Chinese post-stroke patients. The aim of this study was to explore whether there were gender differences on clinical characteristics and outcomes in Chinese patients after ischemic stroke by using the data from the China National Stroke Registry (CNSR).
Capsaicin-induced Activation of ERK1/2 and Its Involvement in GAP-43 Expression and CGRP Depletion in Organotypically Cultured DRG Neurons
Cellular and Molecular Neurobiology. Apr, 2013 | Pubmed ID: 23430271
Low concentrations of capsaicin (CAP) stimulate and high concentrations of CAP can be toxic to the primary sensory neurons of the dorsal root ganglion (DRG). CAP induces the phosphorylation of extracellular signal-regulated protein kinases 1/2 (ERK1/2) in DRG neurons. The effect of the activation of ERK1/2 by different concentrations of CAP on growth-associated protein 43 (GAP-43) expression and calcitonin gene-related peptide (CGRP) depletion in DRG neurons remains unknown. In the present study, organotypic embryonic 15-day-old rat DRG explants were used to determine the effect of different concentrations of CAP on GAP-43 expression and CGRP depletion. The results showed that, compared to unstimulated control cultures, GAP-43 and pERK1/2 protein levels increased at a low concentration (2 μmol/L) of CAP and decreased at a higher concentration (10 μmol/L). The number of CGRP-immunoreactive (IR) migrating neurons also decreased in CAP-treated cultures. The increase in GAP-43 levels and CGRP depletion could be blocked by the administration of ERK1/2 inhibitor PD98059. The results of the present study imply that CAP at different concentrations has different effects on GAP-43 expression and CGRP depletion. These effects were involved in the activation of ERK1/2 in organotypically cultured DRG neurons stimulated with CAP. These data may provide new insights for further development potential therapeutic applications of CAP with moderate dose on neurogenic inflammation.
Stroke; a Journal of Cerebral Circulation. May, 2013 | Pubmed ID: 23444308
The association between hypertension (HTN) and stroke recurrence is unclear, but may be influenced by different subtypes of stroke. This study aims to explore whether HTN contributes to the recurrence of certain subtypes of ischemic stroke (IS).
Infection, Genetics and Evolution : Journal of Molecular Epidemiology and Evolutionary Genetics in Infectious Diseases. Jun, 2013 | Pubmed ID: 23453987
To investigate the diversity of rabies virus (RABV) matrix protein (M) gene in the current Chinese rabies epidemic, we fully examined M gene of 63 street RABVs (Virus isolated from naturally infected animals), and performed phylogenetic and mutational analysis. Our results indicate that the Chinese RABV M gene is well conserved with 90.6% to 100% amino acid similarity. Analysis of the mutations indicates that the sequences can be divided into four groups with each group defined by distinct substitutions. The PPxY motif and residue E58, which are essential for efficient virus production and pathogenicity, were completely conserved. The estimated mean rate of nucleotide substitution was 4.6×10(-4) substitutions per site per year, and the estimated average time of the most recent common ancestor (TMRCA) was 265 years ago based on the M gene of Chinese street RABVs, which are similar to previously reported values for the glycoprotein (G) and nucleoprotein (N) gene. This indicates that the genomic RNA of RABVs circulating worldwide is stable; G, N and M genes are evolving at a similar rate. This study showed that although the Chinese RABV strains could be divided into distinct clades based on the phylogenetic analysis, their functional domains of M proteins were highly conserved.
Life Sciences. May, 2013 | Pubmed ID: 23454170
Antitumour effects of pentapeptide (LH) derived from donkey serum albumin hydrolysates were tested against tumour cells both in vitro and in vivo. The mechanism of LH induced tumour cell apoptosis was investigated.
Neurology India. Jan-Feb, 2013 | Pubmed ID: 23466837
Background: Recent genome-wide and locus-specific association studies identified RNF213 as an important Moyamoya disease (MMD) susceptibility gene. But the results of these studies are limited by the few subjects, different methodologies and ethnicities. Aims: To investigate the association between p.R4810K (rs 112735431, ss179362673; G > A) and p.R4859K (c.14576 G > A) polymorphisms of the RNF213 gene and MMD susceptibility. Settings and Design: We conducted a meta-analysis to evaluate the association. Materials and Methods: Two investigators independently searched the PubMed, Medline, and Embase databases for studies published before October 2012. For included studies, we performed meta-analyses using Cochrane RevMan software. Statistical Analysis: Summary odds ratios (ORs) and 95% confidence intervals (CIs) for RNF213 p.R4810K and p.R4859K polymorphisms; MMD were calculated in a fixed-effects model and a random effects model whenever appropriate. Results: Five eligible studies were reviewed and analyzed, which included two studies for p.R4810K polymorphisms (421 cases and 1214 controls) and three studies for p.R4859K polymorphisms (398 cases and 765 controls). Overall, the pooled results indicated that both p.R4810K polymorphisms and p.R4859K polymorphisms were associated with MMD risk (OR 92.03, 95% CI 54.06-156.65, P < 0.00001 and OR 157.53, 95% CI 85.37-290.7, P < 0.00001, respectively). Stratified analyses by ethnicity revealed the population attributable risks in the Japanese and Korean populations were larger than that in the Chinese population (P =0.0006). Conclusions: This meta-analysis demonstrated that there are strong associations between p.R4859K and p.R4810K polymorphisms of the RNF213 gene and MMD. The discoveries of its association with MMD may help in early diagnosis and prevention of this disease. Further study is still necessary to clarify the biochemical function and pathological role of RNF213 in MMD.
One-pot Protocol for Bimetallic Pt/Cu Hexapod Concave Nanocrystals with Enhanced Electrocatalytic Activity
Scientific Reports. 2013 | Pubmed ID: 23470501
Nanomaterials with particular nanostructures which usually possess special properties always attract considerable attention. A novel bimetallic Pt/Cu hexapod nanostructure was prepared by a facile one-pot strategy. The formation mechanism was investigated by the time sequential evolution experiments and the hexapod concave nanostructures originated from the Pt/Cu rhombic dodecahedron. Further electrochemical measurements indicated the bimetallic Pt/Cu hexapod concave nanocrystals showed enhanced catalytic activities. It is believed that these novel nanostuctures would open up new opportunities for catalytic applications.
Cell Biochemistry and Biophysics. Mar, 2013 | Pubmed ID: 23479334
The epidemiologic studies indicated an association of obesity with increased incidence of colorectal, breast and ovarian cancer. Further studies found a positive correlation between increased serum oxLDL and an increased risk of the three cancers. In contrast, our previous studies found a negative correlation between the serum oxLDL levels and the risk of leukemia and esophageal cancer. Identification of the variability of cytotoxicity of oxLDL-induced on different types of cell lines is important for understanding the mechanism of oxLDL involved in the tumorigenesis. In the present study, we investigated the effective impacts of oxLDL on the proliferation and apoptosis for the human umbilical vein endothelial cells (HUVEC) and two cancer cell lines (EC-9706 and K562/AO2 with multi-drug resistance). HUVEC, K562/AO2 and EC-9706 cell lines were cultured in the presence of oxLDL, and cell proliferation was tested by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, apoptosis and cell cycle by flow cytometer, mRNA expression by RT-PCR and protein expression by Western blot. OxLDL could inhibit proliferation and apoptosis of the three cell lines; however, there were significant differences of effective action on the viability and apoptosis. The dose of oxLDL-induced cytotoxicity on HUVEC was higher than that on the two tumor cells. The antibody of lectin-like oxLDL receptor-1 (LOX-1-ab) can block oxLDL-induced cytotoxicity. Cells apoptosis is mediated by reducing Bcl-2 and increasing Bax and caspase-3 mRNA and protein expression. This study showed the dose of oxLDL-induced cytotoxicity on HUVEC was higher than that on K562/AO2 and EC-9706 tumor cells. The antibody of LOX-1 receptor can block the oxLDL-induced cytotoxicity.
Stroke; a Journal of Cerebral Circulation. May, 2013 | Pubmed ID: 23482598
To develop and validate a risk score (acute ischemic stroke-associated pneumonia score [AIS-APS]) for predicting in-hospital stroke-associated pneumonia (SAP) after AIS.
Different Responses of Galanin and Calcitonin Gene-related Peptide to Capsaicin Stimulation on Dorsal Root Ganglion Neurons in Vitro
Regulatory Peptides. Jun, 2013 | Pubmed ID: 23499803
Both galanin (Gal) and calcitonin gene-related peptide (CGRP) are sensory neuropeptides which expressed in dorsal root ganglion (DRG) neurons and are involved in nociceptive processing. Capsaicin (CAP) influences nociceptive processing via influencing the expression of sensory neuropeptides in primary sensory neurons. However, little is known about the alterations of Gal and CGRP expression at the same condition stimulated by CAP. In the present study, primary cultured DRG neurons were used to determine the different responses of Gal and CGRP to CAP stimulation. DRG neurons were cultured for 48 hours and then exposed to CAP (2 μmol/L), capsazepine (CPZ) (2 μmol/L) plus CAP (2 μmol/L), or extracellular signal-regulated kinase 1/2 (ERK1/2) inhibitor PD98059 (10 μmol/L) plus CAP (2 μmol/L) for an additional 24hours. The DRG neurons were continuously exposed to culture media as a control. After that, the levels of Gal mRNA and CGRP mRNA of DRG neurons were determined using real time-PCR analysis. Gal and CGRP expression in situ was detected by an immunofluorescent labeling technique. The levels of phosphorylated-ERK1/2 (pERK1/2) protein were detected using a Western blot assay. The results showed that CAP evoked increases of Gal and its mRNA and decreases of CGRP and its mRNA in DRG neurons. Administration of either CPZ or PD98059 blocked the effects of CAP. These data indicate that Gal and CGRP shared different responses to CAP stimulation. Gal and CGRP may have different effects in nociceptive processing during neurogenic inflammation.
International Journal of Molecular Sciences. 2013 | Pubmed ID: 23507754
A novel sequence that functions as a promoter element for moderate constitutive expression of transgenes, designated as the PtMCP promoter, was isolated from the woody perennial Populus tomentosa. The PtMCP promoter was fused to the GUS reporter gene to characterize its expression pattern in different species. In stable Arabidopsis transformants, transcripts of the GUS reporter gene could be detected by RT-PCR in the root, stem, leaf, flower and silique. Further histochemical and fluorometric GUS activity assays demonstrated that the promoter could direct transgene expression in all tissues and organs, including roots, stems, rosette leaves, cauline leaves and flowers of seedlings and maturing plants. Its constitutive expression pattern was similar to that of the CaMV35S promoter, but the level of GUS activity was significantly lower than in CaMV35S promoter::GUS plants. We also characterized the promoter through transient expression in transgenic tobacco and observed similar expression patterns. Histochemical GUS staining and quantitative analysis detected GUS activity in all tissues and organs of tobacco, including roots, stems, leaves, flower buds and flowers, but GUS activity in PtMCP promoter::GUS plants was significantly lower than in CaMV35S promoter::GUS plants. Our results suggested that the PtMCP promoter from poplar is a constitutive promoter with moderate activity and that its function is presumably conserved in different species. Therefore, the PtMCP promoter may provide a practical choice to direct moderate level constitutive expression of transgenes and could be a valuable new tool in plant genetic engineering.
Proceedings of the National Academy of Sciences of the United States of America. Apr, 2013 | Pubmed ID: 23509253
Innate-like splenic marginal zone (MZ) and peritoneal cavity B1 B lymphocytes share critical responsibilities in humoral responses but have divergent B-cell receptor (BCR) signaling features. A discrete marker of these subsets with tyrosine-based dual regulatory potential termed "Fc receptor-like 5" (FCRL5) was investigated to explore this discrepancy. Although FCRL5 repressed the robust BCR activity that is characteristic of MZ B cells, it had no influence on antigen receptor stimulation that is blunted in peritoneal cavity-derived B1 B cells. The molecular basis for the receptor's inhibitory function derived from recruitment of the Src homology-2 domain-containing tyrosine phosphatase 1 (SHP-1) to a cytoplasmic immunoreceptor tyrosine-based inhibitory motif. Surprisingly, mutagenesis of this docking site unearthed coactivation properties for FCRL5 that were orchestrated by independent association of the Lyn Src-family kinase with an intracellular immunoreceptor tyrosine-based activation motif-like sequence. FCRL5's unique binary regulation directly correlated with SHP-1 and Lyn activity, which, like BCR function, differed between MZ and B1 B cells. These findings collectively imply a specialized counterregulatory role for FCRL molecules at the intersection of innate and adaptive immunity.
Surgical and Radiologic Anatomy : SRA. Oct, 2013 | Pubmed ID: 23512027
The posterior forearm is an excellent donor site for the vascular pedicled cutaneous flaps; yet, there is surprisingly little detailed anatomical information based on clinical decision making. This study was undertaken to evaluate the anatomical basis of the dorsal forearm perforator flaps and to provide anatomical landmarks to facilitate flap elevation.
Enhanced Differentiation Potential of Human Amniotic Mesenchymal Stromal Cells by Using Three-dimensional Culturing
Cell and Tissue Research. Jun, 2013 | Pubmed ID: 23515591
The therapeutic potential of human amniotic mesenchymal stromal cells (hAMSCs) remains limited because of their differentiation towards mesenchymal stem cells (MSCs) following adherence. The aim of this study was to develop a three-dimensional (3-D) culture system that would permit hAMSCs to differentiate into cardiomyocyte-like cells. hAMSCs were isolated from human amnions of full-term births collected after Cesarean section. Immunocytochemistry, immunofluorescence and flow cytometry analyses were undertaken to examine hAMSC marker expression for differentiation status after adherence. Membrane currents were determined by patch clamp analysis of hAMSCs grown with or without cardiac lysates. Freshly isolated hAMSCs were positive for human embryonic stem-cell-related markers but their marker profile significantly shifted towards that of MSCs following adherence. hAMSCs cultured in the 3-D culture system in the presence of cardiac lysate expressed cardiomyocyte-specific markers, in contrast to those maintained in standard adherent cultures or those in 3-D cultures without cardiac lysate. hAMSCs cultured in 3-D with cardiac lysate displayed a cardiomyocyte-like phenotype as observed by membrane currents, including a calcium-activated potassium current, a delayed rectifier potassium current and a Ca(2+)-resistant transient outward K(+) current. Thus, although adherence limits the potential of hAMSCs to differentiate into cardiomyocyte-like cells, the 3-D culture of hAMSCs represents a more effective method of their culture for use in regenerative medicine.
Molecular Ecology. Apr, 2013 | Pubmed ID: 23517327
Bartonella quintana is a bacterium that causes a broad spectrum of diseases in humans including trench fever. Humans were previously considered to be the primary, if not the only, reservoir hosts for B. quintana. To identify the animal reservoir and extend our understanding of the ecological and evolutionary history of B. quintana, we examined blood samples from macaques and performed multilocus sequence typing (MLST) analysis. We demonstrated the prevalence of B. quintana infection was common in macaques from main primate centres in mainland China. Overall, 18.0% (59/328) of rhesus macaques and 12.7% (39/308) of cynomolgus macaques were found to be infected with B. quintana by blood culture and/or polymerase chain reaction. The infection was more frequently identified in juvenile and young monkeys compared with adult animals. In contrast with the relatively low level of sequence divergence of B. quintana reported in humans, our investigation revealed much higher genetic diversity in nonhuman primates. We identified 44 new nucleotide variable sites and 14 novel sequence types (STs) among the B. quintana isolates by MLST analysis. Some STs were found only in cynomolgus macaques, while some others were detected only in rhesus macaques, suggesting evidence of host-cospeciation, which were further confirmed by phylogenetic analysis and Splits decomposition analysis. Our findings suggest that trench fever may primarily be a zoonotic disease with macaques as the natural hosts.
Chemical Communications (Cambridge, England). Aug, 2013 | Pubmed ID: 23518781
Herein we have identified an optimal catalyst, Pd1Ag1.7, for the tandem reductive amination between nitroarenes and aldehydes (selectivity > 93%). Key to the success is the ability to control the compositions of the investigational Pd1-xAgx (x = 0-1) catalysts, as well as the clear composition dependent activity/selectivity trend observed in this study. This catalyst features a wide substrate scope, excellent recyclability, activity and selectivity under ambient conditions.
Journal of Neurosurgical Anesthesiology. Jul, 2013 | Pubmed ID: 23519370
The effect of propofol on proliferation of adult neural stem cells (ANSCs) is unclear. We investigated the effect of propofol on cultured rat ANSCs and the underlying molecular mechanisms, especially the role of activated cAMP response element binding protein (CREB).
Oral Surgery, Oral Medicine, Oral Pathology and Oral Radiology. Jul, 2013 | Pubmed ID: 23522641
Evaluate the impact of cervical metastasis on the survival of patients with squamous cell carcinoma (SCC) of the hard palate.
Effects of Neuregulin-1β on Growth-associated Protein 43 Expression in Dorsal Root Ganglion Neurons with Excitotoxicity Induced by Glutamate in Vitro
Neuroscience Research. May-Jun, 2013 | Pubmed ID: 23524246
Neuregulin-1β (NRG-1β) is a growth factor with potent neuroprotective capacity. Growth-associated protein 43 (GAP-43) is expressed in dorsal root ganglion (DRG) neurons and an indicator of neuronal survival in vitro. The purpose of present study is to evaluate the effects of NRG-1β on GAP-43 expression in DRG neurons with excitotoxicity induced by glutamate (Glu) in vitro. The phosphatidylinositol 3-kinase (PI3K)/Akt and extracellular signal-regulated protein kinase 1/2 (ERK1/2) signaling pathways involved in these effects were also determined. Embryonic rat DRG neurons were treated with Glu in the absence or presence of NRG-1β and PI3K inhibitor LY294002 and/or ERK1/2 inhibitor PD98059. After that, GAP-43 mRNA and GAP-43 protein levels were analyzed by real time-PCR and western blot assay, respectively. GAP-43 expression in situ was determined by immunofluorescent labeling. The results showed that the decreased GAP-43 levels induced by Glu could be partially reversed by the presence of NRG-1β. Inhibitors (LY294002, PD98059) either alone or in combination blocked the effects of NRG-1β. These data provide new insights of the actions of NRG-1β in sensory neurons.
Novel Yeast-based Strategy Unveils Antagonist Binding Regions on the Nuclear Xenobiotic Receptor PXR
The Journal of Biological Chemistry. May, 2013 | Pubmed ID: 23525103
Ketoconazole binds to and antagonizes pregnane X receptor (PXR) activation.
Repair of Lipopolysaccharide-induced Acute Lung Injury in Mice by Endothelial Progenitor Cells, Alone and in Combination with Simvastatin
Chest. Sep, 2013 | Pubmed ID: 23539119
Endothelial progenitor cells (EPCs) are involved in endothelium repair of acute lung injury (ALI). Numerous studies have demonstrated that statins can promote EPC function in vitro and in vivo; therefore, the purpose of this study was to determine whether simvastatin enhances the function of EPCs participating in the repair of ALI.
Journal of Biomechanics. Apr, 2013 | Pubmed ID: 23540725
In recent years, dynamic mechanical loading has been shown to effectively enhance bone remodeling. The current study attempted to research the counter-effect of constrained dynamic loading on osteoporosis (OP) in ovariectomized (OVX) mice. Female Kunming (KM) mice were randomly divided into 2 groups: SHAM and OVX. The right ulnas of the OVX mice were subjected to a 4-week constrained dynamic loading protocol, and the mechanical properties, trabecular micromorphology parameters and biochemical indices of osteogenesis were evaluated. We detected higher levels of tissue alkaline phosphatase (AKP) and serum bone gamma-carboxyglutamic-acid-containing proteins (BGPs), better trabecular micromorphology parameters and ulnar mechanical properties in the loading group than in the nonloading group. In summary, constrained dynamic loading could prevent ovariectomy-induced osteoporosis by facilitating osteogenesis, improving trabecular microstructure and enhancing bone mechanical properties.
High Pretreatment Serum Lactate Dehydrogenase Level Correlates with Disease Relapse and Predicts an Inferior Outcome in Locally Advanced Nasopharyngeal Carcinoma
European Journal of Cancer (Oxford, England : 1990). Jul, 2013 | Pubmed ID: 23541571
Here, we evaluate the prognostic effect of pretreatment serum lactate dehydrogenase (LDH) in locally advanced nasopharyngeal carcinoma (NPC).
Cutting Edge: Defective Follicular Exclusion of Apoptotic Antigens Due to Marginal Zone Macrophage Defects in Autoimmune BXD2 Mice
Journal of Immunology (Baltimore, Md. : 1950). May, 2013 | Pubmed ID: 23543760
Marginal zone macrophages (MZMs) act as a barrier to entry of circulating apoptotic debris into the follicles of secondary lymphoid organs. In autoimmune BXD2 mice, there is a progressive reduction in the function and numbers of MZMs. Absence of MZMs results in retention of apoptotic cell (AC) debris within the marginal zone (MZ) and increased loading of AC Ags on MZ B cells and MZ-precursor (MZ-P) B cells. The MZ-P B cells are capable of translocating the AC Ags to the follicular zone and stimulating T cells. Both MZMs and MZ-P B cells from BXD2 mice express low levels of tolerogenic signals and high levels of inflammatory signals. Thus, the current study suggests a multifaceted mechanism in which MZMs maintain tolerance to apoptotic autoantigens and suppress their translocation to follicles. Lack of clearance of apoptotic debris by MZMs drives follicular Ag-transportation by MZ-P B cells to stimulate an autoimmune response.
Potential of Co-culture of Nucleus Pulposus Mesenchymal Stem Cells and Nucleus Pulposus Cells in Hyperosmotic Microenvironment for Intervertebral Disc Regeneration
Cell Biology International. Aug, 2013 | Pubmed ID: 23554141
Nucleus pulposus mesenchymal stem cells (NPMSCs) are a potential cell source for intervertebral disc (IVD) regeneration, but little is known about their response to IVD-like high osmolarity (400 mOsm). This study was to investigate the viability, proliferation and protein biosynthesis of nucleus pulposus cells (NPCs), NPMSCs and co-cultured NPMSCs-NPCs under IVD-like high osmolarity conditions. NPCs and NPMSCs were isolated and cultured under standard and IVD-like high osmolarity conditions for 1 or 2 weeks. Cell viability was measured by annexin V-FITC and PI staining, and cell proliferation measured by MTT assay. The expression of SOX-9, aggrecan and collagen-II was measured by RT-PCR and Western blot analyses. IVD-like high osmolarity condition slightly inhibited cell viability and decreased the expression of SOX-9, aggrecan and collagen-II at the mRNA and protein levels in all groups compared with standard condition. NPMSCs could tolerate IVD-like high osmolarity, and NPCs-NPMSCs co-culture increased cell proliferation and the expression of SOX-9, aggrecan and collagen-II under both culture conditions, suggesting that co-culture of NPMSCs-NPCs has potential application for IVD regeneration.
A Novel Method to Assay Molecular Chaperone Activity of HSP70: Evaluation of Drug Resistance in Cancer Treatment
Biosensors & Bioelectronics. Mar, 2013 | Pubmed ID: 23562728
In this work, we have proposed a novel method to specifically assay the molecular chaperone activity of HSP70 based on the HSP70-substrate peptide interaction. By selectively labeling the substrate peptide of HSP70 via host-guest interaction with two different cucurbituril species, the HSP70-substrate peptide interaction can be transduced into detectable signal readout. By using the signal readout, assay of the molecular chaperone activity of HSP70 can be achieved. Moreover, by using our method, chaperone activity of HSP70 can serve as a reliable indicator of drug resistance in cancer treatment. The experimental results reveal that enhanced chaperone activity of HSP70 is observed in both drug-resistant cancer cell line and the serum of cancer victim subject to anti-cancer therapy. Therefore, the proposed method to assay the molecular chaperone activity of HSP70 can be a tool of efficiency in evaluating therapeutic response in HSP70-targeted cancer treatment.
Efficient Synthesis of Highly Substituted Pyrroles Through a Pd(OCOCF3)2-catalyzed Cascade Reaction of 2-alkenal-1,3-dicarbonyl Compounds with Primary Amines
Chemical Communications (Cambridge, England). May, 2013 | Pubmed ID: 23584213
We describe an unprecedented Pd(OCOCF3)2-catalyzed cascade process for the synthesis of highly functionalized 1,2,3,5-tetrasubstituted pyrroles with high efficiency. Unlike documented methods relying on preformed enamines and active halogenated terminal alkenes, the process employs simple 2-alkenal-dicarbonyls and primary amines in 'one-pot'.
[Effects of Huannao Yicong Recipe Extract on the Learning and Memory and Related Factors of Abeta Generation in the Brain of APP Transgenic Mice]
Zhongguo Zhong Xi Yi Jie He Za Zhi Zhongguo Zhongxiyi Jiehe Zazhi = Chinese Journal of Integrated Traditional and Western Medicine / Zhongguo Zhong Xi Yi Jie He Xue Hui, Zhongguo Zhong Yi Yan Jiu Yuan Zhu Ban. Jan, 2013 | Pubmed ID: 23596795
To study the effects of Huannao Yicong Recipe (HNYCR)extract on the learning and memory ability, and the expressions of amyloid precursor protein (APP), beta-site APP-cleaving enzyme 1 (BACE1), presenilin-1 (PS-1), and beta amyloid protein (Abeta)in hippocampus CA1 area of APP transgenic mice, and to explore its mechanisms for treating Alzheimer's disease (AD).
Biomedical Engineering Online. 2013 | Pubmed ID: 23597232
When studying and designing an artificial bone in vitro with similar features and functionality of natural bone by tissue engineering technology, the culturing environment, especially the mechanical environment is supposed to be an important factor, because a suitable mechanical environment in vitro may improve the adaptability of the planted-in tissue engineering bone in the body. Unfortunately, up to now, the relationship between mechanical stimuli and natural bone growth has not yet been precisely determined, and it is so imperative for a prior study on effect of mechanical loading on growth of the natural bone cultured in vitro.
The CD79α (HM47/A9) Antibody is Effective in Distinguishing Between Primary Hepatocellular Carcinoma and Primary Intrahepatic Cholangiocarcinoma
Oncology Letters. Apr, 2013 | Pubmed ID: 23599762
Hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC) are two major forms of primary liver cancer. The aim of this study was to investigate CD79α (HM47/A9) antibody expression patterns in normal liver, HCC and ICC samples. HM47/A9 expression was examined in tissues surrounding liver cancer in adults, 8-week embryos and 20-week embryos. In total, 82 cases of HCC, 31 cases of ICC and 11 cases of combined HCC and cholangiocarcinoma (cHCC-CC) were reviewed. HM47/A9 expression was observed as early as 8-week embryo liver tissue and exhibited focal granular cytoplasmic positivity, which was maintained throughout life. All 82 HCC cases demonstrated cytoplasmic granular positivity for HM47/A9, while no ICC cases were immunostained with HM47/A9. No CC components in cHCC-CC expressed the HM47/A9 antibody. A high number of HCC components in cHCC-CC showed positive staining for HM47/A9 [10/11 (90.9%)]. Our results suggest that HM47/A9 may be employed effectively to differentiate HCC from ICC.
Osteoblasts Subjected to Mechanical Strain Inhibit Osteoclastic Differentiation and Bone Resorption in a Co-culture System
Annals of Biomedical Engineering. Oct, 2013 | Pubmed ID: 23609024
Bone remodeling is strictly mediated by the coupled activities of osteoblasts and osteoclasts, which are responsible for bone formation and resorption, respectively. Although many papers have been published on the mechanical responses of osteoblasts and osteoclasts, little is known about their communication during mechanical loading. In this study, a novel co-culture system was first established using Transwell culture inserts; MC3T3-E1 cells were embedded in the lower compartment of the inserts, and RAW264.7 cells were co-cultured in the upper compartment. The MC3T3-E1 cells were subjected to a mechanical strain of 2500 με at 0.5 Hz to investigate the effect of strain-loaded osteoblasts on co-cultured osteoclasts. The results showed that osteoblast-like cells were activated with an increase of alkaline phosphatase (ALP) activities. The strain-conditioned medium caused decreased activity of tartrate-resistant acid phosphatase and reduced the number of mature multinucleated osteoclasts, which subsequently resulted in the suppressed formation of resorption pits. The expression levels of cathepsin-K and matrix metalloproteinase-9 were also depressed by the strain-conditioned medium. In addition, we found that the expression ratio between osteoprotegerin (OPG) and receptor activator of NF-kB ligand in osteoblasts was significantly up-regulated due to the enhanced levels of OPG. In summary, we conclude that the strain-stimulated osteoblasts inhibited the differentiation and bone resorption of osteoclasts and that the mechanism was associated with the increased secretion of OPG in osteoblasts.
Which Patients with Chronic Obstructive Pulmonary Disease Benefit from the Addition of an Inhaled Corticosteroid to Their Bronchodilator? A Cluster Analysis
BMJ Open. 2013 | Pubmed ID: 23613569
To identify subsets of chronic obstructive pulmonary disease (COPD) patients who are more protected from exacerbations with the use of an inhaled corticosteroid/long-acting β2 agonist (ICS/LABA) combination, compared with the use of LABA monotherapy.
Microfluidic Affinity and ChIP-seq Analyses Converge on a Conserved FOXP2-binding Motif in Chimp and Human, Which Enables the Detection of Evolutionarily Novel Targets
Nucleic Acids Research. Jul, 2013 | Pubmed ID: 23625967
The transcription factor forkhead box P2 (FOXP2) is believed to be important in the evolution of human speech. A mutation in its DNA-binding domain causes severe speech impairment. Humans have acquired two coding changes relative to the conserved mammalian sequence. Despite intense interest in FOXP2, it has remained an open question whether the human protein's DNA-binding specificity and chromatin localization are conserved. Previous in vitro and ChIP-chip studies have provided conflicting consensus sequences for the FOXP2-binding site. Using MITOMI 2.0 microfluidic affinity assays, we describe the binding site of FOXP2 and its affinity profile in base-specific detail for all substitutions of the strongest binding site. We find that human and chimp FOXP2 have similar binding sites that are distinct from previously suggested consensus binding sites. Additionally, through analysis of FOXP2 ChIP-seq data from cultured neurons, we find strong overrepresentation of a motif that matches our in vitro results and identifies a set of genes with FOXP2 binding sites. The FOXP2-binding sites tend to be conserved, yet we identified 38 instances of evolutionarily novel sites in humans. Combined, these data present a comprehensive portrait of FOXP2's-binding properties and imply that although its sequence specificity has been conserved, some of its genomic binding sites are newly evolved.
A Microfluidic System for Cell Type Classification Based on Cellular Size-independent Electrical Properties
Lab on a Chip. Jun, 2013 | Pubmed ID: 23640025
This paper presents a microfluidic system enabling cell type classification based on continuous characterization of size-independent electrical properties (e.g., specific membrane capacitance (C(specific membrane)) and cytoplasm conductivity (σ(cytoplasm)). In this study, cells were aspirated continuously through a constriction channel, while cell elongation and impedance profiles at two frequencies (1 kHz and 100 kHz) were measured simultaneously. Based on a proposed distributed equivalent circuit model, 1 kHz impedance data were used to evaluate cellular sealing properties with constriction channel walls and 100 kHz impedance data were translated to C(specific membrane) and σ(cytoplasm). Two lung cancer cell lines of CRL-5803 cells (n(cell) = 489) and CCL-185 cells (n(cell) = 487) were used to evaluate this technique, producing a C(specific membrane) of 1.63 ± 0.52 μF cm(-2) vs. 2.00 ± 0.60 μF cm(-2), and σ(cytoplasm) of 0.90 ± 0.19 S m(-1)vs. 0.73 ± 0.17 S m(-1). Neural network-based pattern recognition was used to classify CRL-5803 and CCL-185 cells, producing success rates of 65.4% (C(specific membrane)), 71.4% (σ(cytoplasm)), and 74.4% (C(specific membrane) and σ(cytoplasm)), suggesting that these two tumor cell lines can be classified based on their electrical properties.
American Journal of Human Genetics. May, 2013 | Pubmed ID: 23643380
Genetic mapping of complex diseases to date depends on variations inside or close to the genes that perturb their activities. A strong body of evidence suggests that changes in gene expression play a key role in complex diseases and that numerous loci perturb gene expression in trans. The information in trans variants, however, has largely been ignored in the current analysis paradigm. Here we present a statistical framework for genetic mapping by utilizing collective information in both cis and trans variants. We reason that for a disease-associated gene, any genetic variation that perturbs its expression is also likely to influence the disease risk. Thus, the expression quantitative trait loci (eQTL) of the gene, which constitute a unique "genetic signature," should overlap significantly with the set of loci associated with the disease. We translate this idea into a computational algorithm (named Sherlock) to search for gene-disease associations from GWASs, taking advantage of independent eQTL data. Application of this strategy to Crohn disease and type 2 diabetes predicts a number of genes with possible disease roles, including several predictions supported by solid experimental evidence. Importantly, predicted genes are often implicated by multiple trans eQTL with moderate associations. These genes are far from any GWAS association signals and thus cannot be identified from the GWAS alone. Our approach allows analysis of association data from a new perspective and is applicable to any complex phenotype. It is readily generalizable to molecular traits other than gene expression, such as metabolites, noncoding RNAs, and epigenetic modifications.
Neurosurgical Review. May, 2013 | Pubmed ID: 23645140
Background and objective: Sylvian fissure arteriovenous malformations (AVMs) are among the most challenging AVMs to manage surgically. The estimates of their risk factors and prediction of their long-term prognosis are crucial for clinical decision-making. The authors conducted a retrospective review to patients with sylvian AVMs treated microsurgically to evaluate the risk factors associated with long-term prognosis. Methods: Forty-one patients with sylvian fissure AVMs treated microsurgically between June 2009 and December 2011 were retrospectively reviewed with a mean follow-up time of 23Â months (range 6-35Â months). Chi-square test was utilized to compare proportions and rank-sum test to compare ordinal materials. Odds ratios (ORs) were used to assess risk factors associated with postoperative short-term outcome and long-term adverse outcome (mRS scores 3-6). Results: One patient died in 1Â month after surgery. Eighteen (43.9Â %) patients had postoperative transient neurological deterioration. Good outcomes (mRS scores 0-2) were observed in 29 (72.5Â %) patients in the follow-up. From the multiple logistic regression, a history of AVM bleeding and deep venous drainage increase the risk of postoperative transient neurological deterioration, with ORâ€‰=â€‰8.211 and ORâ€‰=â€‰4.869, respectively. A history of AVM bleeding was a risk factor for long-term adverse outcome, with ORâ€‰=â€‰7. Conclusions: Despite different Sugita classification subtypes, sylvian fissure AVMs' long-term results with microsurgical resection are better than expected; a history of AVM bleeding is a risk factor for postoperative temporary neurological deterioration and for long-term adverse outcome, while the AVM deep venous drainage is a risk factor only for temporary neurological deterioration.
Journal of the American Chemical Society. May, 2013 | Pubmed ID: 23647245
Previous efforts to enhance thermoelectric performance have primarily focused on reduction in lattice thermal conductivity caused by broad-based phonon scattering across multiple length scales. Herein, we demonstrate a design strategy which provides for simultaneous improvement of electrical and thermal properties of p-type PbSe and leads to ZT ~ 1.6 at 923 K, the highest ever reported for a tellurium-free chalcogenide. Our strategy goes beyond the recent ideas of reducing thermal conductivity by adding two key new theory-guided concepts in engineering, both electronic structure and band alignment across nanostructure-matrix interface. Utilizing density functional theory for calculations of valence band energy levels of nanoscale precipitates of CdS, CdSe, ZnS, and ZnSe, we infer favorable valence band alignments between PbSe and compositionally alloyed nanostructures of CdS1-xSex/ZnS1-xSex. Then by alloying Cd on the cation sublattice of PbSe, we tailor the electronic structure of its two valence bands (light hole L and heavy hole Σ) to move closer in energy, thereby enabling the enhancement of the Seebeck coefficients and the power factor.
25-Hydroxyvitamin D(3)-loaded PLA Microspheres: in Vitro Characterization and Application in Diabetic Periodontitis Models
AAPS PharmSciTech. Jun, 2013 | Pubmed ID: 23653087
This study aimed at the preparation of a sustained-release 25-hydroxyvitamin D(3) (25OHD) treatment for diabetic periodontitis, a known complication of diabetes. 25OHD-loaded polylactic acid (PLA) microspheres were prepared using oil-in-water emulsion-solvent evaporation method. The prepared microspheres exhibited intact surfaces, with average sizes ranging from 42.3 to 119.4 μm. The encapsulation efficiency ranged from 79.2% (w/w) to 88.5% (w/w), and the drug content was between 15.8% (w/w) and 17.8% (w/w). Drug release from the produced microspheres followed a near-to-zero-order release pattern and lasted over 10 weeks. In an in vitro model of diabetic periodontitis, the abnormal morphological changes and the decrease in the cell viability of bone marrow stromal cells could be effectively attenuated after the 25OHD-loaded microsphere application. Additionally, in a rat model of diabetic periodontitis, alveolar bone loss was inhibited and osteoid formation in the periodontium was promoted upon 25OHD-loaded microsphere treatment. In conclusion, 25OHD-loaded PLA microspheres may provide an effective approach for the treatment of this disease.
Design of a Bi-functional Peptide for Protein Assays: Observation of Cortactin Expression in Human Placenta
Chemical Communications (Cambridge, England). Jun, 2013 | Pubmed ID: 23657365
A bi-functional peptide is designed to incorporate protein recognition and signal amplification functions into a single short peptide sequence.
Growth-associated Protein-43 Expression in Cocultures of Dorsal Root Ganglion Neurons and Skeletal Muscle Cells with Different Neurotrophins
Muscle & Nerve. Jun, 2013 | Pubmed ID: 23666783
Both target skeletal muscle (SKM) cells and neurotrophins (NTs) are essential for the maintenance of neuronal function and nerve-muscle communication. The effects of different NTs and SKM cells on growth-associated protein-43 (GAP-43) expression in dorsal root ganglion (DRG) neurons have not been clarified.
Color Doppler Imaging Analysis of Retrobulbar Blood Flow Velocities in Primary Open-Angle Glaucomatous Eyes: A Meta-Analysis
PloS One. 2013 | Pubmed ID: 23675419
To analyze the diagnostic value of color Doppler imaging (CDI) of blood flow in the retrobulbar vessels of eyes with primary open-angle glaucoma (POAG).
A Cobalt-based 3D Porous Framework with Excellent Catalytic Ability for the Selective Oxidation of Cis-cyclooctene
Dalton Transactions (Cambridge, England : 2003). Jul, 2013 | Pubmed ID: 23685616
A 3D porous framework [Co3(μ2-OH)4(I)2]·2H2O (I = hypoxanthine) with two types of 1D channels possess excellent catalytic ability for the selective oxidation of cis-cyclooctene.
Virologica Sinica. Jun, 2013 | Pubmed ID: 23689982
[Optimization of Biocontrol Agent Burkholderia Pyrrocinia Strain JK-SH007 Fermentation by Response Surface Methodology]
Sheng Wu Gong Cheng Xue Bao = Chinese Journal of Biotechnology. Feb, 2013 | Pubmed ID: 23697169
In order to improve ferment efficiency of biocontrol agent Burkholderia pyrrocinia JK-SH007, the fermentation conditions of this strain were optimized. The optimal fermentation conditions were corn steep liquor (13.88 g/L) and glucose (3.37 g/L) by screening test, steepest ascent experiments and response surface analysis. The results showed that the cell density of JK-SH007 (1.18 x 10(9) CFU/mL) increased 1.35 times than before, and there was a 28.84% increase in antifungal activity.
Improving the Performance of Thermophilic Anaerobic Digester Through Recirculation of Low Hydrogen Biogas
Journal of Environmental Science and Health. Part A, Toxic/hazardous Substances & Environmental Engineering. 2013 | Pubmed ID: 23705619
Biogas recirculation was conducted to improve the performance of two thermophilic anaerobic sequenced batch reactors (ASBRs), in which high concentrations of volatile fatty acids (VFAs) were accumulated. To accelerate degradation of VFAs, facilitating acetate consumption via syntrophic acetate oxidation coupled with hydrogenotrophic methanogenesis (SAO-HM) was expected to be effective. Hence, to promote the SAO-HM pathway, hydrogen was removed to create low hydrogen partial pressure (pH2) in reactor RH, yet in reactor RB, hydrogen was not treated. The performance of RB and RH on VFAs degradation and methane production processes was compared at steady stage; the VFAs and soluble microbial products (SMP) in the effluents were monitored. The results showed that low pH2 intensified the SAO reaction, thereby accelerating conversion of acetate to methane, as well as acetate production from glucose and VFAs. Glucose fermentation type was also influenced. VFAs and SMP in the effluents were reduced after the introduction of biogas mixing, which proceeded much faster in RH with low pH2. Recirculation of low hydrogen biogas with SAO-HM pathway being promoted should be more effective to alleviate high acid level stress and to improve the reactor performance.
Biochemical and Biophysical Research Communications. Jun, 2013 | Pubmed ID: 23707718
In the mushroom bodies (MBs) of Drosophila, an analogue of the mammalian olfactory cortex, olfactory stimuli are sparsely encoded by Kenyon cells (KCs) that exhibit a high level of odor selectivity. Sparse coding of olfactory stimuli has significant advantages for maximizing the discrimination power and storage capacity of MBs. The inhibitory gamma-aminobutyric acid (GABA) system is important for regulating information processing in MBs, but its specific role in the sparse coding of odors is unclear. In this study, we investigated the role of the GABA system in the sparse coding of odors using an in vivo calcium imaging strategy, which allowed us to measure the activity of the KC population at single cell resolution while the components of the GABA system were genetically manipulated. We found that the down-regulation of GABAA but not GABAB receptors in KCs reduced the sparseness of odor representations in the MB, as shown by an increase in the population response probability and decrease in the odor selectivity of single KCs. Furthermore, the down-regulation of GABA synthesis in a pair of large GABAergic neurons innervating the entire MB reduced the sparseness of odor representations in KCs. In conclusion, the sparse coding of odors in MBs is regulated by a pair of GABAergic neurons through the GABAA receptors on KCs, thus demonstrating a specific role of the inhibitory GABA system on information processing in the MB.
Yonsei Medical Journal. Jul, 2013 | Pubmed ID: 23709411
Intervertebral disc (IVD) degeneration is implicated as a major cause of low back pain. The alternated phenotypes, reduced cell survival, decreased metabolic activity, loss of matrix production and dystrophic mineralization of nucleus pulposus (NP) cells may be key contributors to progressive IVD degeneration. IVD is the largest avascular structure in the body, characterized by low oxygen tension in vivo. Hypoxia-inducible factor (HIF) is a master transcription factor that is induced upon hypoxia and directs coordinated cellular responses to hypoxic environments. This review summarizes relevant studies concerning the involvement of HIF in the regulation of biological behaviors of NP cells. We describe current data on the expression of HIF in NP cells and further discuss the various roles that HIF plays in the regulation of the phenotype, survival, metabolism, matrix production and dystrophic mineralization of NP cells. Here, we conclude that HIF may be a promising target for the prevention and treatment of IVD degeneration.
A Strategy Enabling Enantioselective Direct Conjugate Addition of Inert Aryl Methane Nucleophiles to Enals with a Chiral Amine Catalyst Under Mild Conditions
Chemistry (Weinheim an Der Bergstrasse, Germany). Jul, 2013 | Pubmed ID: 23712495
Environmental Science & Technology. Jul, 2013 | Pubmed ID: 23742687
Although dissolved organic matter (DOM) could effectively disperse carbon nanotubes (CNTs), sorption characteristics of DOM-suspended CNTs are unclear. In this study, we evaluated the relative contribution to the overall sorption from dissolved humic acid (DHA) coating (decreased sorption) and CNT dispersion (increased sorption). We observed that the sorption coefficients of sulfamethoxazole (SMX) on DHA-suspended CNTs were up to 2 orders of magnitude higher than that on aggregated CNTs. Although the mass percent of suspended CNTs were low (generally less than 1%), their contributions to SMX adsorption were up to 20%. Because DHA and SMX did not interact with each other due to their negative charges, the suspended CNTs may not be completely coated by DHA and they had considerable hydrophobic surface exposed. Importantly, this study provided the first evidence in aqueous phase of the significantly increased surface area of DHA-suspended CNTs relative to the aggregated ones based on (1)H NMR relaxometry measurements. This study emphasizes that in comparison to aggregated CNTs, the suspended ones have amply exposed surface area and thus have greater environmental impacts, such as enhancing the mobility, transport, and possibly exposure of organic contaminants.
Gap Junction Permeability Modulated by Dopamine Exerts Effects on Spatial and Temporal Correlation of Retinal Ganglion Cells' Firing Activities
Journal of Computational Neuroscience. Jun, 2013 | Pubmed ID: 23748559
Synchronized activities among retinal ganglion cells (RGCs) via gap junctions can be increased by exogenous dopamine (DA). During DA application, single neurons' firing activities become more synchronized with its adjacent neighbors. One intriguing question is how the enhanced spatial synchronization alters the temporal firing structure of single neurons. In the present study, firing activities of bullfrog's dimming detectors in response to binary pseudo-random checker-board flickering were recorded via a multi-channel recording system. DA was applied in the retina to modulate synchronized activities between RGCs, and the effect of DA on firing activities of single neurons was examined. It was found that, during application of DA, synchronized activities between single neuron and its neighboring neurons was enhanced. At the meantime, the temporal structures of single neuron spike train changed significantly, and the temporal correlation in single neuron's response decreased. The pharmacological study results indicated that the activation of D1 receptor might have effects on gap junction permeability between RGCs. Our results suggested that the dopaminergic pathway participated in the modulation of spatial and temporal correlation of RGCs' firing activities, and may exert critical effects on visual information processing in the retina.
Virologica Sinica. Jun, 2013 | Pubmed ID: 23760598
Neuroprotective Effect of Insulin-like Growth Factor-1: Effects on Tyrosine Kinase Receptor (Trk) Expression in Dorsal Root Ganglion Neurons with Glutamate-induced Excitotoxicity in Vitro
Brain Research Bulletin. Aug, 2013 | Pubmed ID: 23769847
Insulin-like growth factor-1 (IGF-1) may play an important role in regulating the expression of distinct tyrosine kinase receptor (Trk) in primary sensory dorsal root ganglion (DRG) neurons. Glutamate (Glu) is the main excitatory neurotransmitter and induces neuronal excitotoxicity for primary sensory neurons. It is not known whether IGF-1 influences expression of TrkA, TrkB, and TrkC in DRG neurons with excitotoxicity induced by Glu. In the present study, primary cultured DRG neurons with Glu-induced excitotoxicity were used to determine the effects of IGF-1 on TrkA, TrkB, and TrkC expression. The results showed that IGF-1 increased the expression of TrkA and TrkB and their mRNAs, but not TrkC and its mRNA, in primary cultured DRG neurons with excitotoxicity induced by Glu. Interestingly, neither the extracellular signal-regulated protein kinase (ERK1/2) inhibitor PD98059 nor the phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 blocked the effect of IGF-1, but both inhibitors together were effective. IGF-1 may play an important role in regulating different Trk receptor expression in DRG neurons through ERK1/2 and PI3K/Akt signaling pathways. The contribution of distinct Trk receptors might be one of the mechanisms that IGF-1 rescues dying neurons from Glu excitotoxic injury. These data imply that IGF-1 signaling might be a potential target on modifying distinct Trk receptor-mediated biological effects of primary sensory neurons with excitotoxicity.
Fungal Genetics and Biology : FG & B. Aug, 2013 | Pubmed ID: 23769871
The potential use of arachidonic acid (AA) to enhance the production of β-carotene in Blakeslea trispora was investigated in this work. To study the mechanism of the B. trispora response to AA, we used a systematic analytical approach to investigate the changes in the B. trispora cell metabolome at different time points after AA treatment. A maximum of β-carotene production was obtained when 0.4g/l AA was added after 36h of cultivation. Gas chromatography-mass spectrometry (GC-MS)-based metabolomics approach and a multivariate analysis were used to investigate the intracellular biochemical changes in B. trispora. With the aid of principal component analysis (PCA), the intracellular metabolite profiles of all the groups were distinguished. Moreover, a group classification and pairwise discrimination between the control and AA-treated groups were obtained through partial least-squares-discriminant analysis (PLS-DA), and 27 differential metabolites with variable importance in the projection (VIP) value higher than 1 were identified, which was also confirmed by the subsequent hierarchical cluster analysis (HCA). Separation of the control and AA-treated groups was mainly due to the compounds of the Krebs cycle, fatty acids and amino acids. With the treatment of AA, the glycolysis was enhanced and the use of glucose for fermentation was increased. The increased levels of some fatty acids and decreased levels of amino acids in the AA-treated cells could also be the responses to the addition of AA. Metabolomics provided a powerful methodology to gain insight in metabolic changes induced by metabolic stimulators in microorganisms.
Prevalence, Awareness, Treatment, and Control of Hypertension in the Non-dialysis Chronic Kidney Disease Patients
Chinese Medical Journal. Jun, 2013 | Pubmed ID: 23786938
Data on the epidemiology of hypertension in Chinese non-dialysis chronic kidney disease (CKD) patients are limited. The aim of the present study was to investigate the prevalence, awareness, treatment, and control of hypertension in the non-dialysis CKD patients through a nationwide, multicenter study in China.
Reduction of Major Peanut Allergens Ara H 1 and Ara H 2, in Roasted Peanuts by Ultrasound Assisted Enzymatic Treatment
Food Chemistry. Nov, 2013 | Pubmed ID: 23790845
This study investigated the effects of ultrasound, enzyme concentration and enzyme treatment time on soluble protein and major allergenic proteins (Ara h 1 and Ara h 2) of roasted peanut kernels. A 3-factor, five-level orthogonal experimental design was implemented with various ultrasonication times, concentrations of trypsin or α-chymotrypsin and treatment times. The total soluble proteins were determined by the Bicinchoninic acid (BCA) method, Ara h 1 and Ara h 2 were evaluated by SDS-PAGE and sandwich ELISA. The IgE-binding of peanut extracts was analysed by a competitive inhibition ELISA. Results indicate that ultrasound treatment, followed by protease digestion of peanuts, significantly increased the solubility of peanut protein and decreased the concentrations of Ara h 1 and Ara h 2. The sequential treatment of peanuts by ultrasonication-trypsin-alpha chymotrypsin, resulted in maximum reductions of Ara h 1/Ara h 2, and lowest IgE-binding. This study provides an approach to significantly reduce allergenic proteins in peanut product.
Cell Research. Sep, 2013 | Pubmed ID: 23797855
Voltage-gated potassium (Kv) channels derive their voltage sensitivity from movement of gating charges in voltage-sensor domains (VSDs). The gating charges translocate through a physical pathway in the VSD to open or close the channel. Previous studies showed that the gating charge pathways of Shaker and Kv1.2-2.1 chimeric channels are occluded, forming the structural basis for the focused electric field and gating charge transfer center. Here, we show that the gating charge pathway of the voltage-gated KCNQ2 potassium channel, activity reduction of which causes epilepsy, can accommodate various small molecule ligands. Combining mutagenesis, molecular simulation and electrophysiological recording, a binding model for the probe activator, ztz240, in the gating charge pathway was defined. This information was used to establish a docking-based virtual screening assay targeting the defined ligand-binding pocket. Nine activators with five new chemotypes were identified, and in vivo experiments showed that three ligands binding to the gating charge pathway exhibit significant anti-epilepsy activity. Identification of various novel activators by virtual screening targeting the pocket supports the presence of a ligand-binding site in the gating charge pathway. The capability of the gating charge pathway to accommodate small molecule ligands offers new insights into the gating charge pathway of the therapeutically relevant KCNQ2 channel.
The New England Journal of Medicine. Jul, 2013 | Pubmed ID: 23803136
Stroke is common during the first few weeks after a transient ischemic attack (TIA) or minor ischemic stroke. Combination therapy with clopidogrel and aspirin may provide greater protection against subsequent stroke than aspirin alone.
Death Receptor 5-targeted Depletion of Interleukin-23-producing Macrophages, Th17, and Th1/17 Associated with Defective Tyrosine Phosphatase in Mice and Patients with Rheumatoid Arthritis
Arthritis and Rheumatism. Oct, 2013 | Pubmed ID: 23818173
Bidirectional interactions between granulocyte-macrophage colony-stimulating factor-positive (GM-CSF+) T cells and interferon regulatory factor 5-positive (IRF-5+) macrophages play a major role in autoimmunity. In the absence of SH2 domain-containing phosphatase 1 (SHP-1), GM-CSF-stimulated cells are resistant to death receptor (DR)-mediated apoptosis. The objective of this study was to determine whether TRA-8, an anti-DR5 agonistic antibody, can eliminate inflammatory macrophages and CD4 T cells in the SHP-1-deficient condition.
Transformation of Odor Selectivity from Projection Neurons to Single Mushroom Body Neurons Mapped with Dual-color Calcium Imaging
Proceedings of the National Academy of Sciences of the United States of America. Jul, 2013 | Pubmed ID: 23818618
Although the response properties of most neurons are, to a large extent, determined by the presynaptic inputs that they receive, comprehensive functional characterization of the presynaptic inputs of a single neuron remains elusive. Toward this goal, we introduce a dual-color calcium imaging approach that simultaneously monitors the responses of a single postsynaptic neuron together with its presynaptic axon terminal inputs in vivo. As a model system, we applied the strategy to the feed-forward connections from the projection neurons (PNs) to the Kenyon cells (KCs) in the mushroom body of Drosophila and functionally mapped essentially all PN inputs for some of the KCs. We found that the output of single KCs could be well predicted by a linear summation of the PN input signals, indicating that excitatory PN inputs play the major role in generating odor-selective responses in KCs. When odors failed to activate KC output, local calcium transients restricted to individual postsynaptic sites could be observed in the KC dendrites. The response amplitudes of the local transients often correlated linearly with the presynaptic response amplitudes, allowing direct assay of the strength of single synaptic sites. Furthermore, we found a scaling relationship between the total number of PN terminals that a single KC received and the average synaptic strength of these PN-KC synapses. Our strategy provides a unique perspective on the process of information transmission and integration in a model neural circuit and may be broadly applicable for the study of the origin of neuronal response properties.
Acta Biochimica Et Biophysica Sinica. Sep, 2013 | Pubmed ID: 23824073
Recent studies have shown that microRNA-21 (miR-21) contributes to tumor resistance to chemotherapy. Interestingly, we have found that berberine could inhibit miR-21 expression in several cancer cell lines. In this study, we investigated whether berberine could modulate the sensitivity of ovarian cancer cells to cisplatin and explored the mechanism. The cisplatin-resistant SKOV3 cells that were incubated with berberine combined with cisplatin had a signiﬁcantly lower survival than the cisplatin alone group and enhanced cisplatin-induced apoptosis. Berberine could inhibit miR-21 expression and function in ovarian cancer, as shown by an enhancement of its target PDCD4, an important tumor suppressor in ovarian cancer. The results suggested that berberine could modulate the sensitivity of cisplatin via regulating miR-21/PDCD4 axis in the ovarian cancer cells.
Quasi-solid-state Rechargeable Lithium-ion Batteries with a Calixquinone Cathode and Gel Polymer Electrolyte
Angewandte Chemie (International Ed. in English). Aug, 2013 | Pubmed ID: 23825051
Incidence and Risk of Hypomagnesemia in Advanced Cancer Patients Treated with Cetuximab: A Meta-analysis
Oncology Letters. Jun, 2013 | Pubmed ID: 23833666
Hypomagnesemia is a serious adverse event for patients treated with cetuximab, an inhibitor of endothelial growth factor receptor (EGFR). However, no significant association has yet been established between cetuximab and hypomagnesemia in randomized controlled clinical trials (RCTs). The present study conducted a systematic review and meta-analysis of published RCTs to assess the overall risk of hypomagnesemia associated with cetuximab. PubMed, the Cochrane Central Register of Controlled Trials, Embase and the American Society of Clinical Oncology conferences were searched for relevant RCTs. Quantitative analysis was carried out to evaluate the association between hypomagnesemia and cetuximab. A total of 7,045 patients with a variety of advanced cancers from 10 trials were included in the analysis. The overall incidence of grade 3/4 hypomagnesemia in patients receiving cetuximab was 3.9% [95% confidence interval (CI), 2.6-4.3%]. Patients treated with cetuximab had a significantly increased risk of grade 3/4 hypomagnesemia compared with patients treated with control medication, with a relative risk (RR) of 8.60 (95% CI, 5.08-14.54). Risk was observed to vary with tumor type. The study concluded that cetuximab is associated with a significant risk of hypomagnesemia in patients with advanced cancer receiving concurrent chemotherapy.
Clinical Features and Independent Predictors in the Further Development of Rheumatoid Arthritis in Undifferentiated Arthritis
Rheumatology International. Nov, 2013 | Pubmed ID: 23835879
This study aims to investigate the prognosis of undifferentiated arthritis (UA) and to estimate the putative predictors contributing to predict the development of UA into rheumatoid arthritis (RA); thus, it could improve appropriate medical intervention. A retrospective cohort study of 218 patients with an initial diagnosis of UA and 2-year follow-up monitoring was carried out. The baseline information including demographic variables, clinical features, and laboratory data was collected. A logistic regression model was used for the statistical analysis. After 2 years of follow-up, 20.18 % of UA patients evolved into RA, but 33.03 % remained undifferentiated. Meanwhile, 25.23 % went into remission, and 21.56 % developed into other connective tissue diseases. Univariate and multivariate analysis showed that the titer of antibodies to cyclic citrullinated peptide (anti-CCP), tender joint count and duration of morning stiffness were independent predictors for the development of RA. The area under the curve (AUC) of duration of morning stiffness (0.81) was largest, followed by tender joint count (0.74). The AUC of anti-CCP antibodies (0.68) was higher than that of rheumatoid factor of IgM type (IgM-RF) (0.60), and the combination of these two antibodies was significantly higher than each alone (P < 0.001). In conclusion, UA patients had variable clinical outcomes and prognosis. Only the titer of anti-CCP antibodies, tender joint count, and duration of morning stiffness, instead of IgM-RF, could predict the development of RA. Although the anti-CCP antibody was better than the IgM-RF in predicting RA, a combined detection of them still improved the diagnostic performance.
Ticks and Tick-borne Diseases. Sep, 2013 | Pubmed ID: 23838022
Anaplasma phagocytophilum and Babesia microti were isolated from a Rattus norvegicus in the middle east of China through propagation in experimental mice. Their molecular biological characteristics were described. The public health and veterinary significance of the dual infection of the 2 tick-borne agents deserve further investigation.
Effects of 25-hydroxyvitamin D3 on Cathelicidin Production and Antibacterial Function of Human Oral Keratinocytes
Cellular Immunology. May-Jun, 2013 | Pubmed ID: 23850962
Vitamin D and its metabolites have been recognized as key determinants in innate immune modulation. In this study, we investigated the regulation of antibacterial functions of oral keratinocyte cells by 25-hydroxyvitamin D3 (25VD3). OKF6/TERT2 cells, an immortalized human oral keratinocyte cell line, were transfected with or without 24-hydroxylase small interfering RNA (siRNA) and incubated with different amounts of 25VD3. These epithelial cells expressed high levels of inactivating 24-hydroxylase (CYP24A1) and relatively low levels of activating 1α-hydroxylase (CYP27B1) in the presence of 25VD3. 25VD3 influenced the expression of vitamin D-driven genes and cathelicidin in a dose-related manner. SiRNA specific to 24-hydroxylase augmented the cathelicidin production and subseqently influenced the antibacterial activity on multispecies of oral pathogens. These observations suggest that 25VD3 is capable of stimulating cathelicidin production and modulating antibacterial function upon CYP24A1 knochdown in oral epithelial cells, and indicate novel mechanisms that 25VD3 may enhance antibacterial ability in oral keratinocytes.
Clinicopathological Significance of Hypoxia-inducible Factor-1 Alpha Polymorphisms in Cancers: Evidence from a Meta-analysis
Tumour Biology : the Journal of the International Society for Oncodevelopmental Biology and Medicine. Oct, 2013 | Pubmed ID: 23857282
The associations between hypoxia-inducible factor-1 alpha (HIF-1α) and clinicopathological characteristics of cancers have been evaluated in various studies, with the conflicting results. Therefore, we conducted a meta-analysis by combining available data to derive a more precise estimation of the association. PubMed, Embase, and China National Knowledge Infrastructure (CNKI) were searched until February 2013 to identify eligible studies. A total of 25 studies were included, with all studies investigating the role of HIF-1α C1772T polymorphism in clinicopathological parameters in cancers while 17 of them investigating HIF-1α G1790A polymorphism only. Results suggested that HIF-1α C1772T polymorphism was associated with histological grade of cancer (T/T + C/T vs. C/C, grade 3 vs. grade 2: OR = 1.51, 95% CI = 1.08-2.13; grade 2 vs. grade 1: OR = 0.67, 95% CI = 0.46-0.97) and increased risk of lymph node metastasis (T/T + C/T vs. C/C: OR = 1.38, 95% CI = 1.13-1.68). HIF-1α G1790A polymorphism was found to be associated with increased risk of larger tumor size (G/G + G/A vs. A/A: OR = 1.64, 95% CI = 1.04-2.58) and borderline significant risk of lymph node metastasis (G/G + G/A vs. A/A: OR = 1.33, 95% CI = 1.00-1.78). Therefore, HIF-1α polymorphisms could be a potential prognostic factor for cancer. Further studies with larger data set and well-designed models are required to validate our findings.
Molecular Diversity. Nov, 2013 | Pubmed ID: 23857318
Aromatase, a rate-limiting enzyme catalyzing the conversion of androgen to estrogen, is overexpressed in human breast cancer tissue. Aromatase inhibitors (AIs) have been used for the treatment of estrogen-dependent breast cancer in post-menopausal women by blocking the biosynthesis of estrogen. The undesirable side effects in current AIs have called for continued pursuit for novel candidates with aromatase inhibitory properties. This study explores the chemical space of all known AIs as a function of their physicochemical properties by means of univariate (i.e., statistical and histogram analysis) and multivariate (i.e., decision tree and principal component analysis) approaches in order to understand the origins of aromatase inhibitory activity. Such a non-redundant set of AIs spans a total of 973 compounds encompassing both steroidal and non-steroidal inhibitors. Substructure analysis of the molecular fragments provided pertinent information on the structural features important for ligands providing high and low aromatase inhibition. Analyses were performed on data sets stratified according to their structural scaffolds (i.e., steroids and non-steroids) and bioactivities (i.e., actives and inactives). These analyses have uncover a set of rules characteristic to active and inactive AIs as well as revealing the constituents giving rise to potent aromatase inhibition.
Growth Temperature-induced Changes in Biomass Accumulation, Photosynthesis and Glutathione Redox Homeostasis As Influenced by Hydrogen Peroxide in Cucumber
Plant Physiology and Biochemistry : PPB / Société Française De Physiologie Végétale. Oct, 2013 | Pubmed ID: 23860263
Hydrogen peroxide (H2O2) and glutathione (GSH) are involved in the stress response in plants. To elucidate the role of H2O2 in the acclimation of CO2 assimilation under sub- or supra-optimal growth temperatures, we examined the effect and interaction of H2O2 manipulation on the photosynthetic metabolism of cucumber plants (Cucumis sativus L.) grown under five temperature regimes spanning above and below the optimal growth temperature; 11/9, 18/15, 25/20, 32/27, and 39/33 °C (day/night), with or without dimethylthiourea (DMTU) or H2O2 treatment. As expected, exposure to sub- or supra-optimal growth temperatures resulted in decreased plant growth, associated with a decline in CO2 assimilation (Asat), Rubisco content, and activities of enzymes involved in the CO2 assimilation, as well as a decrease in the ratio of reduced (GSH) to oxidized (GSSG) glutathione (GSH/GSSG). Foliar application of H2O2 promoted, whilst DMTU retarded the capacity of plants to acclimate to non-optimal growth temperatures; this was consistently shown in altered activity of redox-sensitive enzymes involved in CO2 assimilation. These results strongly suggest that the influence of growth temperature on CO2 assimilation was primarily targeted at the activities of the redox-sensitive enzymes of CO2 assimilation. Meanwhile, the data suggest that the cellular H2O2 level is an important signal for the glutathione-dependent regulation of redox-sensitive enzymes of CO2 assimilation in cucumber plants.
Health and Quality of Life Outcomes. 2013 | Pubmed ID: 23866850
Many patients with cancer experience depression and anxiety, and an associated decrease in quality of life (QOL) during radiation therapy (RT). The main objective of the study was to determine the benefits of psychosocial interventions for cancer patients who received RT.
Molecular Phylodynamic Analysis Indicates Lineage Displacement Occurred in Chinese Rabies Epidemics Between 1949 to 2010
PLoS Neglected Tropical Diseases. Jul, 2013 | Pubmed ID: 23875035
Rabies remains a serious problem in China with three epidemics since 1949 and the country in the midst of the third epidemic. Significantly, the control of each outbreak has been followed by a rapid reemergence of the disease. In 2005, the government implemented a rabies national surveillance program that included the collection and screening of almost 8,000 samples. In this work, we analyzed a Chinese dataset comprising 320 glycoprotein sequences covering 23 provinces and eight species, spanning the second and third epidemics. Specifically, we investigated whether the three epidemics are associated with a single reemerging lineage or a different lineage was responsible for each epidemic. Consistent with previous results, phylogenetic analysis identified six lineages, China I to VI. Analysis of the geographical composition of these lineages revealed they are consistent with human case data and reflect the gradual emergence of China I in the third epidemic. Initially, China I was restricted to south China and China II was dominant. However, as the epidemic began to spread into new areas, China I began to emerge, whereas China II remained confined to south China. By the latter part of the surveillance period, almost all isolates were China I and contributions from the remaining lineages were minimal. The prevalence of China II in the early stages of the third epidemic and its established presence in wildlife suggests that it too replaced a previously dominant lineage during the second epidemic. This lineage replacement may be a consequence of control programs that were dominated by dog culling efforts as the primary control method in the first two epidemics. This had the effect of reducing dominant strains to levels comparable with other localized background stains. Our results indicate the importance of effective control strategies for long term control of the disease.
Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi = Chinese Journal of Otorhinolaryngology Head and Neck Surgery. Apr, 2013 | Pubmed ID: 23886100
The aim of this study was to describe a new technique of combined hyoid bone and thyrohyoid membrane flap in laryngeal reconstruction after tumor resection, and to evaluate outcome.
Systems Perspectives on Erythromycin Biosynthesis by Comparative Genomic and Transcriptomic Analyses of S. Erythraea E3 and NRRL23338 Strains
BMC Genomics. Jul, 2013 | Pubmed ID: 23902230
S. erythraea is a Gram-positive filamentous bacterium used for the industrial-scale production of erythromycin A which is of high clinical importance. In this work, we sequenced the whole genome of a high-producing strain (E3) obtained by random mutagenesis and screening from the wild-type strain NRRL23338, and examined time-series expression profiles of both E3 and NRRL23338. Based on the genomic data and transcriptpmic data of these two strains, we carried out comparative analysis of high-producing strain and wild-type strain at both the genomic level and the transcriptomic level.
Zhonghua Yi Xue Za Zhi. Apr, 2013 | Pubmed ID: 23902888
To explore the clinical and laboratory characteristics of patients with lupus enteritis to provide rationales for clinical diagnosis and treatment.
Digestion. 2013 | Pubmed ID: 23921155
Biliary atresia (BA) is a devastating disease of infants, invariably leading to cirrhosis, end-stage liver disease, and death if untreated. The etiology of BA is unknown, although infectious, immune, and genetic causes have been suggested. This study was designed to investigate whether polymorphism of the ITGB2 (CD18) gene is associated with susceptibility to BA.
Overexpression of High Mobility Group A1 Protein in Human Uveal Melanomas: Implication for Prognosis
PloS One. 2013 | Pubmed ID: 23935884
There is increasing evidence that the high mobility group A1 (HMGA1) protein, which functions as a transcriptional master regulator, plays critical roles in tumor progression. We evaluated HMGA1 expression in 89 primary uveal melanomas (UM) by immunohistochemistry to determine the clinicopathological and prognostic value of HMGA1 in UM after adjusting for other prognostic variables. Nuclear expression of HMGA1 was detected in 44% UMs. High expression levels of HMGA1 were more frequent in UMs with high levels of epithelioid cell pattern, mitoses count, and Ki67 labeling index (P = 0.025, P<0.0001, P = 0.0018; respectively), and HMGA1 expression levels were directly correlated with Ki67 labeling indexes and mitoses counts (R = 0.31, P <0.0001; R = 0.27, P<0.0068; respectively). High expression of HMGA1 was also independently associated with an increased risk of distant metastases as determined using the Cox proportional hazards regression model (multivariate hazard ratio: 3.44; 95% confidence interval: 1.56-7.60; log rank P = 0.0022). Moreover, high HMGA1 expression was associated with shorter UM-specific survival (multivariate hazard ratio: 2.41; 95% confidence interval: 1.10-5.53; log rank P = 0.041). These findings suggest that high levels of HMGA1 are associated with adverse clinical outcomes in UM patients and that further evaluation of HMGA1 as a potential therapeutic target in UM is warranted.
Chemical Communications (Cambridge, England). Sep, 2013 | Pubmed ID: 23939597
An unprecedented alkylation reaction of malononitriles with enantioenriched primary allylic amines has been developed in a stereospecific manner through palladium-catalyzed sp(3) C-N bond cleavage without additives at room temperature.
Microarray Analysis of Gene Expression Profiles of Schistosoma Japonicum Derived from Less-susceptible Host Water Buffalo and Susceptible Host Goat
PloS One. 2013 | Pubmed ID: 23940568
Water buffalo and goats are natural hosts for S. japonicum in endemic areas of China. The susceptibility of these two hosts to schistosome infection is different, as water buffalo are less conducive to S. japonicum growth and development. To identify genes that may affect schistosome development and survival, we compared gene expression profiles of schistosomes derived from these two natural hosts using high-throughput microarray technology.
Gold Nanoisland Arrays by Repeated Deposition and Post-deposition Annealing for Surface-enhanced Raman Spectroscopy
Nanotechnology. Sep, 2013 | Pubmed ID: 23942082
Gold nanoisland arrays with well controlled growth were achieved by repeated sputtering deposition and post-deposition annealing processes. When each deposition was set at 5 nm (nominal thickness based on gold mass), the single deposition and annealing process (single process) yielded gold nanoisland arrays with an average diameter of ~16 nm based on top view scanning electron microscopy (SEM). When the deposition and annealing process was repeated two more times (triple process), top view SEM showed the nanoisland arrays grew to ~38 nm in average diameter. The surface-enhanced Raman spectroscopy (SERS) measurement indicated that triple processed nanoisland arrays led to the highest SERS enhancement, suggesting the necessity of pursuing nanoislands with larger sizes. The gold nanoisland arrays after the triple process were further sputtered with a final layer of gold thin film at different nominal thicknesses. An optimal nominal thickness for SERS was determined experimentally at ~40 nm, as a result of the competition between the positive and negative effects of the final gold deposition. Last, the uniformity of the optimized SERS substrate was investigated on a 5 cm x 5 cm platform. SERS measurements demonstrated a relative standard deviation of ~7% in terms of spectral variation over the entire substrate, rendering the process in the present study a promising fabrication approach for large-scale production of SERS substrates.
The Journal of Chemical Physics. Aug, 2013 | Pubmed ID: 23947845
Effective tight-binding models have been introduced to describe vertical electronic excitations in branched conjugated molecules. The excited-state electronic structure is characterized by quantum particles (excitons) that reside on an irregular lattice (graph) that reflects the molecular structure. The methodology allows for the exciton spectra and energy-dependent exciton scattering matrices to be described in terms of a small number of lattice parameters which can be obtained from quantum-chemical computations using the exciton scattering approach as a tool. We illustrate the tight-binding model approach using the time-dependent Hartree-Fock computations in phenylacetylene oligomers. The on-site energies and hopping constants have been identified from the exciton dispersion and scattering matrices. In particular, resonant, as well as bound states, are reproduced for a symmetric quadruple branching center. The capability of the tight-binding model approach to describe the exciton-phonon coupling and energetic disorder in large branched conjugated molecules is briefly discussed.
Artificial Cells, Nanomedicine, and Biotechnology (Print). Aug, 2013 | Pubmed ID: 23957645
Objective: By in situ polymerization of poly-L-lactic acid (PLLA) and nano-hydroxyapatite (Nano-HA), and finding the best proportion of composite, so as to get ideal interface fixation material. Methods: According to a certain ratio (the mass fraction of Nano-HA, respectively, is 0%, 10%, 20%, 30% and 40%), composite PLLA and Nano-HA by in situ polymerization, and test the performance of this kind of new type of interface fixation such as, bending strength,compressive strength, elastic modulus, scanning electron microscopy (SEM) and degradation experiments in vitro. Then observe its mechanical properties, microstructure, the dispersion of Nano-HA in the PLLA and degradation rate of composite materials. Results: 1. Mechanical tests show that with the increase of Nano-HA content, the tensile strength decreases and the elastic modulus increases; with Nano-HA content of 20%, the bending strength of composite materials presents the peak value (156.8 MPa). 2. SEM scan shows the fracture surface of pure PLLA is relatively smooth; with Nano-HA content of 10%, the fracture surface shows a large number of dimples, and is obvious rough; with Nano-HA content of 20%, the fracture surface is uneven, forming a large number of dimples; with Nano-HA content of 30% or more, the fracture surface becomes more flat, and there are some small dimples. 3. Degradation experiments in vitro show the following: as the degradation time goes on, the pH values of degradation liquid is gradually reduced and the mechanical properties of composite materials also gradually have some decay. Conclusion: With Nano-HA content of 20%, the interface fixation material has a better mechanical properties and degradation properties. According to the best ratio, prepare Nano-HA/PLLA composite artificial materials with good performance.
Case-fatality Ratio and Effectiveness of Ribavirin Therapy Among Hospitalized Patients in China Who Had Severe Fever with Thrombocytopenia Syndrome
Clinical Infectious Diseases : an Official Publication of the Infectious Diseases Society of America. Nov, 2013 | Pubmed ID: 23965284
Background. The wide distribution and high case-fatality ratio of severe fever with thrombocytopenia syndrome (SFTS) have made it a significant public health problem. This study was designed to identify the predictors of fatal outcomes and to evaluate the effectiveness of antiviral therapy in treating SFTS virus (SFTSV)-infected patients. Methods. A cross-sectional study was performed in a general hospital located in Xinyang city, whereas the largest number of patients with SFTS in China were treated during 2011-2012. The primary outcome for the treatment effect analysis was death. Other outcomes included sequential platelet levels and viral loads observed throughout the hospitalization and the interval between the initiation of ribavirin therapy and the return of the platelet count to a normal level. Results. A total of 311 SFTSV-infected patients were included in the study. The most frequent clinical presentations were fever, weakness, myalgia, and gastrointestinal symptoms. Each patient had thrombocytopenia, leukopenia, or both. The case-fatality ratio (CFR) was 17.4% (95% confidence interval [CI], 13.1%-21.6%). Older age (odds ratio [OR], 1.061; 95% CI, 1.023-1.099; P = .001), decreased level of consciousness (OR, 5.397; 95% CI, 2.660-10.948; P < .001), and elevated levels of lactate dehydrogenase (>1200 U/L; OR, 2.620; 95% CI, 1.073-6.399; P = .035) and creatine kinase (>800 U/L; OR, 2.328; 95% CI, 1.129-4.800; P = .022) were significantly associated with fatal outcome. The CFRs were similar between patients who received ribavirin and those who did not. Ribavirin treatment showed no significant effect on either platelet counts or viral loads during hospitalization of patients with fatal or nonfatal cases. Conclusions. These findings can improve knowledge about the characteristics of patients with fatal outcomes and the use of antiviral drug for SFTS.
Dual Release of Dexamethasone and TGF-β3 from Polymeric Microspheres for Stem Cell Matrix Accumulation in a Rat Disc Degeneration Model
Acta Biomaterialia. Dec, 2013 | Pubmed ID: 23973308
Low back pain is frequently caused by nucleus pulposus (NP) degeneration. Tissue engineering is a powerful therapeutic strategy which could restore the normal biomechanical motion of the human spine. Previously we reported that a new nanostructured three-dimensional poly(lactide-co-glycolide) (PLGA) microsphere, which is loaded with dexamethasone and growth factor embedded heparin/poly(l-lysine) nanoparticles via a layer-by-layer system, was an effective cell carrier in vitro for NP tissue engineering. This study aimed to investigate whether the implantation of adipose-derived stem cell (ADSC)-seeded PLGA microspheres into the rat intervertebral disc could regenerate the degenerated disc. Changes in disc height by plain radiograph, T2-weighted signal intensity in magnetic resonance imaging (MRI), histology, immunohistochemistry and matrix-associated gene expression were evaluated in normal controls (NCs) (without operations), a degeneration control (DC) group (with needle puncture, injected only with Dulbecco's modified Eagle's medium), a PLGA microspheres (PMs) treatment group (with needle puncture, PLGA microspheres only injection), and PLGA microspheres loaded with ADSCs treatment (PMA) group (with needle puncture, PLGA microspheres loaded with ADSC injection) for a 24-week period. The results showed that at 24weeks post-transplantation, the PM and PMA groups regained disc height values of ∼63% and 76% and MRI signal intensities of ∼47% and 76%, respectively, compared to the NC group. Biochemistry, immunohistochemistry and gene expression analysis also indicated the restoration of proteoglycan accumulation in the discs of the PM and PMA groups. However, there was almost no restoration of proteoglycan accumulation in the discs of the DC group compared with the PM and PMA groups. Taken together, these data suggest that ADSC-seeded PLGA microspheres could partly regenerate the degenerated disc in vivo after implantation into the rat degenerative intervertebral disc.
Acid-triggered Core Cross-linked Nanomicelles for Targeted Drug Delivery and Magnetic Resonance Imaging in Liver Cancer Cells
International Journal of Nanomedicine. 2013 | Pubmed ID: 23976852
To research the acid-triggered core cross-linked folate-poly(ethylene glycol)-b-poly[N-(N',N'-diisopropylaminoethyl) glutamine] (folated-PEG-P[GA-DIP]) amphiphilic block copolymer for targeted drug delivery and magnetic resonance imaging (MRI) in liver cancer cells.
Protective Effect of Amifostine on High-Dose Methotrexate-Induced Small Intestinal Mucositis in Mice
Digestive Diseases and Sciences. Aug, 2013 | Pubmed ID: 23979434
Amifostine has been shown to be capable of minimizing radiotherapy-induced oral mucositis, but whether it protects small intestinal mucosae from high-dose methotrexate-induced damage is presently unknown.
Neuroscience Bulletin. Oct, 2013 | Pubmed ID: 23990220
Neighboring retinal ganglion cells (RGCs) fire with a high degree of correlation. It has been increasingly realized that visual perception of the environment relies on neuronal population activity to encode and transmit the information contained in stimuli. Understanding how neuronal population activity contributes to visual information processing is essential for understanding the mechanisms of visual coding. Here we simultaneously recorded spike discharges from groups of RGCs in bullfrog retina in response to visual patterns (checkerboard, horizontal grating, and full-field illumination) using a multi-electrode array system. To determine the role of synchronous activity mediated by gap junctions, we measured the correct classification rates of single cells' firing patterns as well as the synchronization patterns of multiple neurons. We found that, under normal conditions, RGC population activity exhibited distinct response features with exposure to different stimulus patterns and had a higher rate of correct stimulus discrimination than the activity of single cells. Dopamine (1 μmol/L) application did not significantly change the performance of single neuron activity, but enhanced the synchronization of the RGC population activity and decreased the rate of correct stimulus pattern discrimination. These findings suggest that the synchronous activity of RGCs plays an important role in the information coding of different types of visual patterns, and a dopamine-induced increase in synchronous activity weakens the population performance in pattern discrimination, indicating the potential role of the dopaminergic pathway in modulating the population coding process.
Clinical Infectious Diseases : an Official Publication of the Infectious Diseases Society of America. Oct, 2013 | Pubmed ID: 23999081
Canadian Journal of Microbiology. Sep, 2013 | Pubmed ID: 24011341
In the fermentative process using Saccharomyces cerevisiae to produce bioethanol, the performance of cells is often compromised by the accumulation of ethanol. However, the mechanism of how S. cerevisiae responds against ethanol stress remains elusive. In the current study, S. cerevisiae cells were cultured in YPD (yeast extract - peptone - dextrose) medium containing various concentrations of ethanol (0%, 2.5%, 5%, 7.5%, 10%, and 15% (v/v)). Compared with the control group without ethanol, the mean cell volume of S. cerevisiae decreased significantly in the presence of 7.5% and 10% ethanol after incubation for 16 h (P < 0.05), and in the presence of 15% ethanol at all 3 sampling time points (1, 8, and 16 h) (P < 0.05). The exposure of S. cerevisiae cells to ethanol also led to an increase in malonyldialdehyde content (P < 0.05) and a decrease in sulfhydryl group content (P < 0.05). Moreover, the observations through transmission electron microscopy enabled us to relate ultrastructural changes elicited by ethanol with the cellular stress physiology. Under ethanol stress, the integrity of the cell membrane was compromised. The swelling or distortion of mitochondria together with the occurrence of a single and large vacuole was correlated with the addition of ethanol. These results suggested that the cell membrane is one of the targets of ethanol, and the degeneration of mitochondria promoted the accumulation of intracellular reactive oxygen species.
Advanced Materials (Deerfield Beach, Fla.). Sep, 2013 | Pubmed ID: 24018703
The use of high-quality graphene as a local probe in combination with photoexcitation is described to establish a deep mechanistic understanding of charge generation/quenching processes underlying the graphene/environment interface. By combing a no-destructive bottom-up assembly technique with senstive graphene-based transistors, a bistable  rotaxane-graphene hybrid device is produced which exhibits a symmetric mirror-image photoswitching effect with logic capabilities.
FoxO Regulates Expression of ABCA6, an Intracellular ATP-binding-cassette Transporter Responsive to Cholesterol
The International Journal of Biochemistry & Cell Biology. Nov, 2013 | Pubmed ID: 24028821
ATP-binding-cassette (ABC) proteins have been recognized as key players in cellular physiological transport processes. ABC transporter A6 (ABCA6) is a member of the ABC subfamily A. Although it was cloned more than 10 years ago, its expression regulation, subcellular localization, and physiologic function remain largely unknown. We here demonstrated that expression of ABCA6 was Forkhead box O (FoxO)-dependent in human endothelial cell line EA.hy926 and human umbilical vein endothelial cells. Two functional FoxO-responsive elements were identified in ABCA6 promoter and characterized in detail. ABCA6 mRNA was suppressed by insulin-like growth factor-1 which stimulates the phosphorylation and inactivation of FoxOs while inhibitor of phosphatidylinositol 3-kinase had the opposite effect. By immunofluorescence and confocal microscopy, ABCA6 protein is localized primarily in an intracellular compartment, likely representing the Golgi apparatus. ABCA6 mRNA was demonstrated to be responsive to cholesterol loading as well as 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) reductase inhibitors in human endothelial cells. Our data provide evidence for an essential role of FoxO proteins in the transcription of ABCA6 in human vascular endothelial cells. Based on its cholesterol responsiveness, a potential involvement of ABCA6 in intracellular lipid transport processes may be anticipated.
Highly Sensitive Protein Detection Based on a Novel Probe with Catalytic Activity Combined with a Signal Amplification Strategy: Assay of MDM2 for Cancer Staging
Chemical Communications (Cambridge, England). Oct, 2013 | Pubmed ID: 24029834
A novel probe with catalytic activity is used for highly sensitive MDM2 detection.
Journal of Hazardous Materials. Aug, 2013 | Pubmed ID: 24036148
Phosphate amendments in calcareous lead (Pb)-contaminated soils to immobilize Pb may be hindered due to competition of Pb with calcium (Ca) that may inhibit the retention of Pb as a precipitation mechanism. This study explored the retention of Pb in a calcareous soil spiked and aged with 500mgkg(-1) Pb(2+) and amended with H2PO4(-). In addition, Ca(2+) was added immediately or three days before or after phosphate, after which ryegrass (Lolium perenne) was planted. Diethylene triamine pentaacetic acid (DTPA)-extractable Pb of the soils in which Ca was added immediately after phosphate was lower than those only amended with phosphate or when Ca was added three days before or after phosphate. The addition of Ca immediately after phosphate resulted in the greatest reduction of ammonia acetate-exchangeable Ca concentration, Olsen-P concentration, and carbonate phase Pb. Higher plant biomass yields were observed for the simultaneous P and Ca treatment. The results of the study demonstrate that co-added Ca and P may help reduce Pb availability by forming fresh Ca-P sorbent phases to retain Pb through an adsorption-substitution mechanism, which may play an important role in the sequestration of Pb in calcareous soils with soluble phosphate in addition to the mechanism of the direct precipitation as pyromorphite.
Pathology Oncology Research : POR. Sep, 2013 | Pubmed ID: 24043589
Prostate cancer is a big killer in many regions especially American men, and this year, the diagnosed rate rises rapidly. We aimed to find the biomarker or any changing in prostate cancer patients. With the development of next generation sequencing, much genomic alteration has been found. Here, basing on the RNA-seq result of human prostate cancer tissue, we tried to find the transcription or non-coding RNA expressed differentially between normal tissue and prostate cancer tissue. 10 T sample data is the RNA-seq data for prostate cancer tissue in this study, we found the differential gene is TFF3-Trefoil factor 3, which was more than seven fold change from prostate cancer tissue to normal tissue, and the most outstanding transcript is C15orf21. Additionally, 9 lncRNAs were found according our method. Finally, we found the many important non-coding RNA related to prostate cancer, some of them were long non-coding RNA (lncRNA).
Seasonal Dynamics of Schistosoma Japonicum Infection in Buffaloes in the Poyang Lake Region and Suggestions on Local Treatment Schemes
Veterinary Parasitology. Nov, 2013 | Pubmed ID: 24045056
Schistosomiasis japonica remains a major public health problem and the Poyang Lake region in Jiangxi province is one of the worst affected endemic areas. Buffaloes play a major role in the transmission of Schistosoma japonicum to humans. The aim of the present study was to increase understanding of the epidemic characteristics of schistosomiasis japonica in water buffaloes in the Poyang Lake region, after achieving the national mid-term goal, and to provide a basis for further interventions. The baseline prevalence in two villages in the Poyang Lake region in May 2010 was compared with respect to usage, sex and age in the total study population. Seasonal dynamics from May 2010 to May 2011 were observed in a natural village in the studied area. The baseline prevalence of infection in both villages (Caohui and Gaozhou) was 4.94% in May 2010. The prevalence in buffalo younger than 12 months was 12.82% in Caohui and 15.11% in Gaozhou, which was significantly higher than that found in those aged 13-24 months and older than 24 months. Of the 28 infected buffaloes, 82.14% (23) were younger than 12 months. The flow of seasonal dynamics showed that S. japonicum infection buffaloes were found from May to July and from November to January of the following year. This survey suggested that it is necessary to conduct two mass treatments (especially for young animals) in late March or early April and November, with an additional treatment of positive animals in July or June.
Tumour Biology : the Journal of the International Society for Oncodevelopmental Biology and Medicine. Sep, 2013 | Pubmed ID: 24046090
Epidemiological studies have assessed the association between HIF-1α polymorphisms and cancer risk. However, the results remained conflicting rather than conclusive. Therefore, we performed a systematic review to provide a complete picture and conducted a meta-analysis to derive a precise estimation. We searched PubMed, Embase, and China National Knowledge Infrastructure (CNKI) databases until July 2013 to identify eligible studies. Data sets (43) from 39 studies with a total of 10,841 cases and 14,682 controls were included. The most commonly investigated polymorphism was C1772T, followed by G1790A, C111A, and rs2057482. Overall, C1772T and G1790A but not rs2057482 were associated with increased risk for cancer. When stratified by cancer type, C1772T was associated with increased risk for cervical cancer (T/T vs. C/T+C/C: OR = 8.80, 95 % CI = 2.30-33.70), prostate cancer (T vs. C: OR = 1.54, 95 % CI = 1.04-2.30), and other cancers (T vs. C: OR = 1.42, 95 % CI = 1.07-1.89), but not oral, breast, colorectal, endometrial, lung, and bladder cancers or renal cell carcinoma. G1790A was associated with marginal but insignificant risk for prostate cancer (A vs. G: OR = 1.46, 95 % CI = 1.00-2.13, P = 0.056) and with increased risk for oral (A vs. G: OR = 9.66, 95 % CI = 1.31-71.15), lung (A vs. G: OR = 2.27, 95 % CI = 1.74-2.96), and other cancers (A vs. G: OR = 2.06, 95 % CI = 1.26-3.37) and renal cell carcinoma (A/A vs. G/A+G/G: OR = 3.05, 95 % CI = 1.36-6.84), but not breast, colorectal, cervical, or bladder cancer. Furthermore, we detected increased cancer risk in haplotypes TA and CA and in those carrying at least one risk allele, and decreased cancer risk in haplotype TG regarding C1772T and G1790A polymorphisms. Further well-designed studies on various cancer types are warranted to verify our findings.
Effects of Endoscopic Mucosal Resection in Patients with Low-Grade Intraepithelial Dysplasia of Esophageal Squamous Cells
Digestive Surgery. Sep, 2013 | Pubmed ID: 24051496
Background: This study evaluated the effects of endoscopic mucosal resection (EMR) on patients with low-grade intraepithelial dysplasia (LGD) of the esophageal squamous cells. Methods: A randomized study recruited 128 LGD patients. These patients were randomly divided into treatment and control groups after the preoperative examination. The treatment group was composed of 63 LGD cases who received EMR. The control group included 65 LGD cases that were not treated with EMR. Clinical interviews and endoscopy were conducted after 30 months as postoperative follow-up. Results: Concerning the percentages of esophageal lesions that changed from serious conditions into slight conditions (namely from high-grade intraepithelial dysplasia (HGD) to LGD, basal cell hyperplasia, esophagitis and normal mucosa) there was a significantly linear trend relationship between the treatment group and control group. In downstaging of dysplasia grade, the total percentage for the 52 cases (82.5%) in the treatment group was significantly higher than that for the 32 cases (49.2%) in the control group (Pearson χ(2) = 15.734, p < 0.001). Also, in patients that remained at the LGD grade or had upstaging of their dysplasia grade, the proportions of the change were significantly different between the two groups. Conclusion: The percentage rate of regression of LGD was increased in the EMR treatment group as compared to that of the control group. EMR may prevent or delay the progression of LGD to HGD. © 2013 S. Karger AG, Basel.
Nanoscale. Nov, 2013 | Pubmed ID: 24056871
In this study we demonstrate that self-doping and surface plasmon resonance could endow a wide-band-gap ternary semiconductor BiOCl with remarkable visible light driven photocatalytic activity on the degradation of organic pollutants and photocurrent generation properties. The self-doped BiOCl with plasmonic silver modification was synthesized by a facile one-pot nonaqueous approach and systematically characterized using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, UV-visible diffuse reflectance spectra, electron spin resonance, and X-ray photoelectron spectroscopy. The photocurrent enhancement was found to be intimately dependent on the irradiation wavelength and matched well with the intensity of the absorption of the Ag nanoparticles. Reactive species trapping experiments and electron spin resonance spectroscopy with 5,5-dimethyl-1-pyrroline-N-oxide spin-trapping adducts confirmed that more oxidative species could be generated from the photogenerated electrons due to the plasmon-excitation of the metallic Ag in the self-doped BiOCl with plasmonic silver modification, which is responsible for the great enhancement of photocatalytic activity and photocurrent. Surface photovoltage spectroscopy and time-resolved photoluminescence spectroscopy results revealed the transfer of plasmon-band-induced electrons from Ag nanoparticles into BiOCl and the acceleration effect of surface plasmon resonance-induced intense oscillating electric fields on this electron transfer. This study would not only provide direct evidence of plasmonic photocatalysis, but also shed light on the design of highly efficient metal-semiconductor composite photocatalysts.
Journal of the American Chemical Society. Nov, 2013 | Pubmed ID: 24059594
After the manner in which coenzymes often participate in the binding of substrates in the active sites of enzymes, pillararene, a macrocycle containing five hydroquinone rings linked through their para positions by methylene bridges, modifies the binding properties of cucurbituril, such that the latter templates azide-alkyne cycloadditions that do not occur in the presence of only the cucurbituril, a macrocycle composed of six glycoluril residues doubly linked through their nitrogen atoms to each other by methylene groups. Here, we describe how a combination of pillararene and cucurbituril interacts cooperatively with bipyridinium dications substituted on their nitrogen atoms with 2-azidoethyl- to 5-azidopentyl moieties to afford, as a result of orthogonal templation, two rotaxanes and one rotaxane in >90% yields inside 2 h at 55 °C in acetonitrile. Since the hydroxyl groups on pillararene and the carbonyl groups on cucurbituril form hydrogen bonds readily, these two macrocycles work together in a cooperative fashion to the extent that the four conformational isomers of pillararene can be trapped on the dumbbell components of the rotaxanes. In the case of the rotaxane, it is possible to isolate a compound containing two pillararene rings with local C5 symmetries. In addition to fixing the stereochemistries of the pillararene rings, the regiochemistries associated with the 1,3-dipolar cycloadditions have been extended in their constitutional scope. Under mild conditions, orthogonal recognition motifs have been shown to lead to templation with positive cooperativity that is fast and all but quantitative, as well as being green and efficient.
MiR-34a Regulates Cisplatin-induce Gastric Cancer Cell Death by Modulating PI3K/AKT/survivin Pathway
Tumour Biology : the Journal of the International Society for Oncodevelopmental Biology and Medicine. Sep, 2013 | Pubmed ID: 24068565
The purposes of this study were to determine the expression profiles of microRNA-34a (miR-34a) in human gastric cancer cell line (SGC-7901) and cisplatin-resistant cell lines (SGC-7901/DDP), and to establish the correlation between miR-34a expression profile and the sensitivity of human gastric cancer cell to cisplatin-based pattern, thereby providing new methods and strategies for treating gastric cancer. Gastric cancer cell line (SGC-7901) and cisplatin-resistant cell line (SGC-7901/DDP) were cultivated in vitro, respectively. Quantitative real-time PCR (qRT-PCR) and Western blot were utilized to determine the expression profiles of miR-34a and survivin in both gastric cancer cell lines. With miR-34a mimic and miR-34a inhibitor transfected into SGC-7901 and SGC-7901/DDP for 48 h, post-transfection changes of miR-34a expression was determined; the effects of miR-34a ectopic expression on the viability of cisplatin-induce gastric cancer cell were assayed by the MTT method. The effects of miR-34a ectopic expression on apoptosis of cisplatin-induce gastric cancer cell were determined by Annexin V/propidium iodide (PI) double staining method and flow cytometry. The effects of miR-34a ectopic expression on the AKT and p-AKT expression of cisplatin-induce gastric cancer cells were determined by Western blot and flow cytometry with the PI3K pathway inhibitor Wortmannin. As shown by qRT-PCR and Western blot analyses, the expression of miR-34a in cisplatin-resistant cell lines decreased significantly in comparison to that of SGC-7901 cell line (p < 0.05), while significant up-regulation of survivin expression was also observed (p < 0.05). Compared with the control group, the expression of miR-34a increased significantly in SGC-7901 cells transfected with miR-34a mimic for 48 h (p < 0.01). After miR-34a inhibitor transfection, the expression of miR-34a decreased significantly (p < 0.05). The viability of cisplatin-induce gastric cancer cells increased significantly (p < 0.05) with significant decrease of apoptosis after miR-34a expression inhibition, as demonstrated by MTT and flow cytometry with miR-34a over-expression, the viability of cisplatin-induce gastric cancer cells decreased significantly (p < 0.05), with significant apoptosis increase (p < 0.05). As shown by Western blot and flow cytometry, in comparison to the control group, Wortmannin could inhibit miR-34a inhibitor and DDP induced up-regulation of p-AKT significantly (p < 0.05) and stimulated apoptosis. In conclusion, miR-34a expression was down-regulated in cisplatin-resistant cell lines. miR-34a over-expression could improve the sensitivity of gastric cancer cells against cisplatin-based chemotherapies, with PI3K/AKT/survivin signaling pathway possibly involved in the mechanism.
Association of Tumor Necrosis Factor Alpha Promoter Polymorphism (TNF-α 238 G/A and TNF-α 308 G/A) with Diabetic Mellitus, Diabetic Retinopathy and Diabetic Nephropathy: A Meta-analysis
Current Eye Research. Sep, 2013 | Pubmed ID: 24073796
Abstract Aim: To examine the association between tumor necrosis factor alpha (TNF-α) polymorphism and risk for diabetic mellitus (DM), diabetic retinopathy (DR) and diabetic nephropathy (DN). Methods: Systematic searches of electronic databases such as PubMed, Medline, Web of knowledge and CNKI, as well as hand searching of the references of identified articles were performed. A total of 8979 subjects in 14 studies from 12 eligible publications were included in this meta-analysis (6 of 12 eligible studies were analyzed for TNF 238 G/A polymorphism and Type 1 DM (T1DM), 5 of 12 were analyzed for TNF 308 G/A polymorphism and DR in Type 2 DM (T2DM), and 3 of 12 were analyzed for TNF 308 G/A polymorphism and DN in T2DM). Pooled odds ratio (OR) with 95% confidence interval (CI) was calculated using fixed or random effects model. The I(2) statistics were used to evaluate between-study heterogeneity. Sensitivity analysis was also performed. Results: The results showed no evidence for significant association between TNF 238 G/A polymorphism and T1DM (for AA + GA versus GG: OR = 0.95, 95% CI = 0.48-1.88, p = 0.89), and also no association between TNF 308 G/A polymorphism and DR and DN risk in T2DM (for AA + GA versus GG: OR = 1.04, 95% CI = 0.87-1.25, p = 0.68; OR = 0.88, 95% CI = 0.71-1.08, p = 0.21; respectively). In addition, the similar results were obtained in the subgroup analysis based on the ethnicity. Conclusions: In summary, results from this meta-analysis suggest that the TNF 238 G/A polymorphism was not associated with T1DM. No association between TNF 308 G/A polymorphism and DR and DN in T2DM was detected.
Highly Selective Detection of Polycyclic Aromatic Hydrocarbons Using Multifunctional Magnetic-luminescent Molecularly Imprinted Polymers
ACS Applied Materials & Interfaces. Nov, 2013 | Pubmed ID: 24083479
A facile method is presented for the selective luminescence detection of trace polycyclic aromatic hydrocarbons (PAHs) based on a combination of the specific recognition of molecularly imprinted polymers (MIPs) and magnetic separation (MS). Multifunctional magnetic-luminescent MIP nanocomposites were fabricated via a one-pot emulsion strategy using polystyrene-co-methacrylic acid copolymer, hydrophobic Fe3O4 nanoparticles and luminescent LaVO4:Eu(3+) nanoparticles as building blocks with a phenanthrene template. The resulting nanocomposites can be employed in a simple method for the luminescence detection of phenanthrene. Furthermore, magnetic separation of the nanocomposites from the target mixture prior to luminescence detection of phenanthrene affords significantly enhanced selectivity and sensitivity, with a 3σ limit of detection (LOD) as low as 3.64 ng/mL. Milk samples spiked with phenanthrene (5.0 μg/mL) were assayed via this method and recoveries ranging from 97.11 to 101.9% were obtained, showing that our strategy is potentially applicable for the preconcentration, recovering, and monitoring of trace PAHs in complex mixtures.
Association of Functional Polymorphisms in the MxA Gene with Susceptibility to Enterovirus 71 Infection
Human Genetics. Oct, 2013 | Pubmed ID: 24085612
Myxovirus resistance A (MxA) is an antiviral protein induced by type I interferons α and β (IFN-α and IFN-β) that can inhibit virus replication. We examined whether the MxA polymorphisms were related to the risk and severity of enterovirus 71 (EV71) infection in Chinese populations. The MxA C-123A and G-88T polymorphisms were genotyped in two independent case-control populations in China by polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) analysis. Multivariate logistic regression analysis was used to calculate adjusted odds ratios (ORs) and 95 % confidence intervals (95 % CIs). MxA messenger RNA was quantified by real-time quantitative PCR in peripheral blood mononuclear cells (PBMCs) from 45 healthy children and 19 patients with EV71 infection. Significantly decreased susceptibility to EV71 infection was observed for the -123A allele and -88T allele carriers, with ORs (95 % CIs) estimated as 0.56 (0.39-0.81) and 0.64 (0.47-0.88), respectively, in the northern population. This association was confirmed in the southern population, with ORs (95 % CIs) estimated as 0.58 (0.38-0.89) and 0.67(0.47-0.95), respectively. The A- 123T- 88 haplotype was also significantly associated with lower risk of EV71 infection in both the northern (OR = 0.62; 95 % CI = 0.44-0.85) and the southern population (OR = 0.63; 95 % CI = 0.43-0.92). Furthermore, we observed higher MxA messenger RNA levels in IFNβ1a-stimulated PBMCs from the -123A or -88T allele carriers compared with that from nocarriers. Our findings suggest that polymorphisms in the MxA promoter may play a role in mediating the susceptibility to EV71 infection in Chinese population.
Ago1 Interacts with RNA Polymerase II and Binds to the Promoters of Actively Transcribed Genes in Human Cancer Cells
PLoS Genetics. Sep, 2013 | Pubmed ID: 24086155
Argonaute proteins are often credited for their cytoplasmic activities in which they function as central mediators of the RNAi platform and microRNA (miRNA)-mediated processes. They also facilitate heterochromatin formation and establishment of repressive epigenetic marks in the nucleus of fission yeast and plants. However, the nuclear functions of Ago proteins in mammalian cells remain elusive. In the present study, we combine ChIP-seq (chromatin immunoprecipitation coupled with massively parallel sequencing) with biochemical assays to show that nuclear Ago1 directly interacts with RNA Polymerase II and is widely associated with chromosomal loci throughout the genome with preferential enrichment in promoters of transcriptionally active genes. Additional analyses show that nuclear Ago1 regulates the expression of Ago1-bound genes that are implicated in oncogenic pathways including cell cycle progression, growth, and survival. Our findings reveal the first landscape of human Ago1-chromosomal interactions, which may play a role in the oncogenic transcriptional program of cancer cells.
Expert Opinion on Therapeutic Patents. Oct, 2013 | Pubmed ID: 24094047
Introduction: Oxytocin is a nine amino acid cyclic peptide hormone with a high degree of uterotonic activity. The oxytocin receptor (Oxtr) is most strongly expressed in the uterus and mammary gland, but can also be found in regions of the brain, showing a neurotransmitter-like activity. The Oxtr knockout mice have no obvious defects in fertility or sexual behavior, but display aberrant social behavior. All of these suggest that Oxtr may become an important therapeutic target for the treatment of a wide range of conditions. Areas covered: This article will highlight the significant progress that has been made in the discovery and development of Oxtr agonists and antagonists in the patent literature between January 2002 and May 2013. Expert opinion: In the past decade, cumulative evidence supports the idea that activation of the Oxtr can have a positive effect upon human cognition and social behavior. The authors suggest that new agonists and antagonists may play an important role in the treatment of disorders such as anxiety, autism or schizophrenia. It may even be that older Oxtr agonists and antagonists, which were used to overcome labor-related dysfunction, may also have a significant impact on human social behavior.
PloS One. 2013 | Pubmed ID: 24098511
Tetrandrine, a bis-benzylisoquinoline alkaloid isolated from the dried root of Hang-Fang-Chi (Stephaniatetrandra S. Moore), has been reported to possess anti-cancer effects on many tumors. In this study, we investigated tetrandrine-induced apoptosis on human gastric cancer BGC-823 cells in vitro and in vivo. The results showed that tetrandrine significantly inhibited cell viability in a dose- and time-dependent manner and induced apoptosis. It increased the apoptosis; upregulation of Bax, Bak, and Bad; and downregulation of Bcl-2 and Bcl-xl in BGC-823 cells. Moreover, tetrandrine increased the activation of caspase-3 and -9, release of cytochrome c, and upregulation of apaf-1, suggesting that tetrandrine-induced apoptosis was related to the mitochondrial pathway. Meanwhile, pretreatment with the pan-caspase inhibitor z-VAD-fmk in BGC-823 cells reduced tetrandrine-induced apoptosis by blocking activation of caspases. Furthermore, tetrandrine effectively inhibited tumor growth via apoptosis induction, which was verified by immunohistochemical analysis in a nude mouse xenograft model. Taken together, we concluded that tetrandrine significantly inhibited the proliferation of gastric cancer BGC-823 cells through mitochondria-dependent apoptosis, which may play a promising role in gastric cancer therapy.
Echocardiographic Assessment of β-adrenergic Stimulation-induced Heart Failure with Reduced Heart Rate in Mice
Clinical and Experimental Pharmacology & Physiology. Sep, 2013 | Pubmed ID: 24107096
Chronic injection with the β-adrenergic receptor (β-AR) agonist isoproterenol (ISO) has been commonly used as an animal model of β-AR-induced cardiac remodeling and heart failure. This ISO-treated model usually shows significantly decreased conscious heart rate (HR). However, the HR in treatment groups is usually adjusted to the same levels by anaesthesia to assess cardiac geometry and function. Here, we reveal a method of echocardiography assessment that represents the true cardiac geometry and function. C57BL/6 mice received 5 mg/kg/day ISO for 12 weeks. Cardiac geometry and function were assessed by high-resolution echocardiography in vehicle- and ISO-treated mice under conscious or varied anesthetic conditions. Cardiac β-AR response was decreased in ISO-treated mice, as evidenced by markedly decreased conscious HR. Vehicle- and ISO-treated mice did not differ in cardiac geometry or function when HR was adjusted to the same level (400 beats/min) in both treatment groups but did differ when using a low (1%) rather than high (1.5% or 2%) isoflurane concentration for HR adjustment. Furthermore, 3-day ISO withdrawal eliminated the difference in conscious HR between the 2 groups. Also, the groups differed in cardiac geometry and function values regardless of isoflurane concentration. Use of isoflurane to decrease HR of treatment groups to the same level may mask the left-ventricular dysfunction of ISO-treated mice. Therefore, we demonstrate that ISO withdrawal eliminates the interference of different basal HR between treatment groups on echocardiography measurements, allowing a more accurate assessment of cardiac pathological and functional changes. This article is protected by copyright. All rights reserved.
Acta Biochimica Et Biophysica Sinica. Nov, 2013 | Pubmed ID: 24108762
Recent studies have shown that microRNA-106a (miR-106a) is overexpressed in gastric cancer and contributes to tumor growth. In this study, we investigated whether miR-106a mediated resistance of the gastric cancer cell line SGC7901 to the chemotherapeutic agent cisplatin (DDP). MiR-106a expression was up-regulated in the DDP resistant cell line SGC7901/DDP compared with its parental line SGC7901. Transfection of miR-106a induced DDP resistance in SGC7901, while suppression of miR-106a in SGC7901/DDP led to enhanced DDP cytotoxicity. Further study indicated that the mechanism of miR-106a-induced DDP resistance involved the expression of phosphatase and tensin homolog deleted from chromosome 10 (PTEN) protein and its downstream phosphatidylinositol 3 kinase (PI3K)/protein kinase B (AKT) pathway. This study provides a novel mechanism of DDP resistance in gastric cancer.
An Externally Head-mounted Wireless Neural Recording Device for Laboratory Animal Research and Possible Human Clinical Use
Conference Proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference. Jul, 2013 | Pubmed ID: 24110386
In this paper we present a new type of head-mounted wireless neural recording device in a highly compact package, dedicated for untethered laboratory animal research and designed for future mobile human clinical use. The device, which takes its input from an array of intracortical microelectrode arrays (MEA) has ninety-seven broadband parallel neural recording channels and was integrated on to two custom designed printed circuit boards. These house several low power, custom integrated circuits, including a preamplifier ASIC, a controller ASIC, plus two SAR ADCs, a 3-axis accelerometer, a 48MHz clock source, and a Manchester encoder. Another ultralow power RF chip supports an OOK transmitter with the center frequency tunable from 3GHz to 4GHz, mounted on a separate low loss dielectric board together with a 3V LDO, with output fed to a UWB chip antenna. The IC boards were interconnected and packaged in a polyether ether ketone (PEEK) enclosure which is compatible with both animal and human use (e.g. sterilizable). The entire system consumes 17mA from a 1.2Ahr 3.6V Li-SOCl2 1/2AA battery, which operates the device for more than 2 days. The overall system includes a custom RF receiver electronics which are designed to directly interface with any number of commercial (or custom) neural signal processors for multi-channel broadband neural recording. Bench-top measurements and in vivo testing of the device in rhesus macaques are presented to demonstrate the performance of the wireless neural interface.
Chemistry, an Asian Journal. Sep, 2013 | Pubmed ID: 24115393
Multicolor upconversion (UC) luminescence of NaYF4 :Yb(3+) /Er(3+) nanoparticles (NPs) was successfully tuned by simply controlling the NaF dosage. Unlike UC nanocrystals previously reported in the literature with multicolor emission obtained by varying the rare-earth dopants, the current work developed a new approach to tune the UC emission color by controlling the NaF concentration without changing the ratio and dosage of rare-earth ions. TEM and powder XRD were used to characterize the shape, size, and composition of the UC luminescent nanocrystals. The luminescence images, emission spectra, and multicolor emission mechanism of the NPs have also been demonstrated. As a result of the excellent ability of this new method to manipulate color emission, this will open up new avenues in the areas of bioprobes, light-emitting devices, color displays, lasers, and so forth. To demonstrate their biological applications, the water-stable, biocompatible, and bioconjugatable NaYF4 :Yb(3+) /Er(3+) @poly(acrylic acid) NPs were synthesized by this developed strategy and applied in targeted-cell UC luminescence imaging.
Posterior Lumbar Interbody Fusion for Aged Patients with Degenerative Spondylolisthesis: is Intentional Surgical Reduction Essential?
The Spine Journal : Official Journal of the North American Spine Society. Oct, 2013 | Pubmed ID: 24119879
Surgical reduction and posterior lumbar interbody fusion (PLIF) is commonly used to recover segmental imbalance in degenerative spondylolisthesis. However, whether intentional reduction of the slipped vertebra during PLIF is essential in aged patients with degenerative spondylolisthesis remains controversial.
International Journal of Pharmaceutics. Oct, 2013 | Pubmed ID: 24126038
The blood-brain barrier (BBB) restricts the transfer and delivery of most drug substances to brain. In this study, a novel nano-drug delivery system for brain-targeting was developed and investigated in vitro and in vivo. Lactoferrin (Lf) was selected as a brain-targeting ligand and conjugated to β-cyclodextrin (β-CD) via the heterobifunctional polyethyleneglycol (PEG) linker NHS-PEG-MAL, yielding Lf conjugated β-cyclodextrin (Lf-CD). UV-vis, FTIR, NMR and transmission electron microscopy (TEM) techniques clearly demonstrated the successful synthesis of Lf-CD nanoparticles with the average diameter of 92.9±16.5nm. Using near-infrared fluorescent dye IR-775 chloride (IR) as a model compound of poorly water-soluble drugs, IR-loaded Lf-CD nanoparticles (Lf-CD/IR) were successfully prepared with a high entrapment efficiency of 98.1±4.8%. Biodistribution and pharmacokinetics of Lf-CD/IR were evaluated in KM mice after intravenous administration. The results of tissue distribution studies revealed that Lf-CD/IR treatment showed greatly improved BBB transport efficiency. In addition, AUC0-2h of IR in brain after Lf-CD/IR treatment was seven fold higher compared with that of IR treatment without Lf-CD nano-carriers, demonstrating that the introduction of Lf-CD drug-delivery system positively resulted in a higher AUC located in brain tissue. These results provide evidence that Lf-CD nanoparticles could be exploited as a potential brain-targeting drug delivery system for hydrophobic drugs and diagnostic reagents which normally fail to pass through the BBB.
Current Eye Research. Dec, 2013 | Pubmed ID: 24131226
Abstract Purpose: To demonstrate the feasibility of fundus camera guided photoacoustic ophthalmoscopy (PAOM) system and its multimodal imaging capabilities. Methods: We integrated PAOM and a fundus camera consisting of a white-light illuminator and a high-sensitivity, high-speed CCD. The fundus camera captures both retinal anatomy and PAOM illumination at the same time to provide a real-time feedback when we position the PAOM illuminating light. We applied the integrated system to image rat eyes in vivo and used full-spectrum, visible (VIS), and near infrared (NIR) illuminations in fundus photography. Results: Both albino and pigmented rat eyes were imaged in vivo. During alignment, different trajectories of PAOM laser scanning were successfully visualized by the fundus camera, which reduced the PAOM alignment time from several minutes to 30 s. In albino eyes, in addition to retinal vessels, main choroidal vessels were observed using VIS-illumination, which is similar to PAOM images. In pigmented eyes, the radial striations of retinal nerve fiber layer were visualized by fundus photography using full-spectrum illumination; meanwhile, PAOM imaged both retinal vessels and the retinal pigmented epithelium melanin distribution. Conclusions: The results demonstrated that PAOM can be well-integrated with fundus camera without affecting its functionality. The fundus camera guidance is faster and easier comparing with our previous work. The integrated system also set the stage for the next-step verification between oximetry methods based on PAOM and fundus photography.
[Assisting Plate with Reamed Intramedullary Nailing for Segmental Fractures of Proximal-middle Tibia]
Beijing Da Xue Xue Bao. Yi Xue Ban = Journal of Peking University. Health Sciences. Oct, 2013 | Pubmed ID: 24136265
To evaluate the efficacy and safety of combining reduction plating with reamed intramedullary nailing for segmental fractures of proximal-middle tibia.
Metabolic Changes During the Pu-erh Tea Pile-Fermentation Revealed by a Liquid Chromatography Tandem Mass-Spectrometry-Based Metabolomics Approach
Journal of Food Science. Oct, 2013 | Pubmed ID: 24138293
In the current study, liquid chromatography-mass spectrometry combined with multivariate statistical analyses was employed to investigate the time-varying biochemical changes during the pile-fermentation process with the emphasis on the active ingredients to clarify the manufacturing process of ripened pu-erh tea as a whole. The metabolite profiles of different manufacturing processes were unique and could be distinguished with the aid of principal component analysis. Furthermore, partial least-squares discriminant analysis revealed a pairwise discrimination between the raw material group and pile-fermentation process groups or the final product group, and 48 differential metabolites with variable importance in the projection value greater than 1 were identified, which was confirmed by the subsequent hierarchical cluster analysis. These results highlight our current understanding of the exact changing process of the bioactive compounds during the pile fermentation, and the global change of these bioactive compounds provides the special flavor, taste, and health promoting effects of ripened pu-erh tea.
Ferrous Iron-dependent Drug Delivery Enables Controlled and Selective Release of Therapeutic Agents in Vivo
Proceedings of the National Academy of Sciences of the United States of America. Nov, 2013 | Pubmed ID: 24145449
The precise targeting of cytotoxic agents to specific cell types or cellular compartments is of significant interest in medicine, with particular relevance for infectious diseases and cancer. Here, we describe a method to exploit aberrant levels of mobile ferrous iron (Fe(II)) for selective drug delivery in vivo. This approach makes use of a 1,2,4-trioxolane moiety, which serves as an Fe(II)-sensitive "trigger," making drug release contingent on Fe(II)-promoted trioxolane fragmentation. We demonstrate in vivo validation of this approach with the Plasmodium berghei model of murine malaria. Malaria parasites produce high concentrations of mobile ferrous iron as a consequence of their catabolism of host hemoglobin in the infected erythrocyte. Using activity-based probes, we successfully demonstrate the Fe(II)-dependent and parasite-selective delivery of a potent dipeptidyl aminopeptidase inhibitor. We find that delivery of the compound in its Fe(II)-targeted form leads to more sustained target inhibition with greatly reduced off-target inhibition of mammalian cathepsins. This selective drug delivery translates into improved efficacy and tolerability. These findings demonstrate the utility of a purely chemical means to achieve selective drug targeting in vivo. This approach may find useful application in parasitic infections and more broadly in any disease state characterized by aberrant production of reactive ferrous iron.
Prognostic Value of ICH Score and ICH-GS Score in Chinese Intracerebral Hemorrhage Patients: Analysis From the China National Stroke Registry (CNSR)
PloS One. 2013 | Pubmed ID: 24146993
No strongevidenceofefficacycurrently exists for different intracerebral hemorrhage (ICH) scoring system in predicting the prognosis of ICH in the Chinese population. This study aimed to test the accuracyof the ICH score and the ICH grading scale (ICH-GS) score in predicting the favorable prognosis in a large cohort of ICH patients in China.
Asymmetric Synthesis of Chiral Dihydrothiopyrans Via an Organocatalytic Enantioselective Formal Thio [3 + 3] Cycloaddition Reaction with Binucleophilic Bisketone Thioethers
Organic Letters. Nov, 2013 | Pubmed ID: 24152030
An unprecedented organocatalytic highly enantioselective approach to a 3,4-dihydro-2H-thiopyran scaffold with two contiguous stereogenic centers has been implemented through a formal thio [3 + 3] cycloaddition process involving a Michael-aldol condensation cascade sequence. Notably, a new class of binucleophilic bisketone thioethers is designed for the process. Furthermore, the fine-tuning of their reactivity enables the cascade process to proceed with highly regioselectively.
A Gold Nanoparticles Colorimetric Assay for Label-free Detection of Protein Kinase Activity Based on Phosphorylation Protection Against Exopeptidase Cleavage
Biosensors & Bioelectronics. Oct, 2013 | Pubmed ID: 24157613
Protein kinases are significant regulators in the cell signaling pathways, and it is still greatly desirable to achieve simple and quick kinase detection. Herein, we present a novel colorimetric gold nanoparticles (AuNPs)/peptide platform for probing the activity and inhibition of protein kinases based on phosphorylation-induced suppression of carboxypeptidase Y (CPY) cleavage. This AuNPs/peptide platform can easily monitor the kinase activity by a UV-vis spectrometer or even by the naked eye. The feasibility of the method has been demonstrated by sensitive measurement of the cAMP-dependent protein kinase (PKA) activity with a low detection limit of 0.232mU/µL and assessment of kinase inhibition by H-89 with an IC50 value of 18.13nM. The assay was also successfully put into practice for the detection of kinase activity in cell lysate. Because of its label-free, homogenous and colorimetric merits, the proposed assay presents great potential in high-throughput screening for kinase-targeted drug discovery.
Formation of Dihydronaphthalenes Via Organocatalytic Enatioselective Michael-Aldol Cascade Reactions with Arylalkanes
Organic Letters. Oct, 2013 | Pubmed ID: 24161207
An organocatalytic highly enantioselective Michael-aldol cascade access to valuable chiral dihydronaphthalenes has been realized. Notably, the strategy via activation of nucleophilic alkyl chains by introducing nitro, chloro, or CF3 group(s) at the ortho- and/or para-position(s) on an aromatic ring renders them readily deprotonated to produce highly reactive nulecophilic species in the cascade process under mild conditions.
Journal of the American Chemical Society. Oct, 2013 | Pubmed ID: 24171644
Motor molecules present in nature convert energy inputs, such as a chemical fuel or incident photons of light, into directed motion and force biochemical systems away from thermal equilibrium. The ability, not only to control relative movements of components in molecules, but also and to drive their components preferentially in one direction relative to each other using versatile stimuli, is one of the keys to future technological applications. Herein, we describe a wholly synthetic, small-molecule system which, under the influence of chemical reagents, electrical potential, or visible light, undergoes unidirectional relative translational motion. Altering the redox state of a cyclobis(paraquat-p-phenylene) ring simultaneously (i) inverts the relative heights of kinetic barriers presented by the two termini - one a neutral 2-isopropylphenyl group and the other a positively charged 3,5-dimethylpyridinium unit - of a constitutionally asymmetric dumbbell, which can impair threading/dethreading of a pseudorotaxane, and (ii) controls the ring's affinity for a 1,5-dioxynaphthalene binding site located at the dumbbell's central core. The formation and subsequent dissociation of the pseudorotaxane by passage of the ring over the neutral and positively charged termini of the dumbbell component in one, and only one, direction relatively defined has been demonstrated by (i) spectroscopic (1H NMR and UV/vis) means and cyclic voltammetry, as well as with (ii) DFT calculations and by (iii) comparison with control compounds in the shape of constitutionally symmetrical pseudorotaxanes, one with two positively charged and the other with two neutral ends. Operation of the system relies solely on reversible, yet stable, noncovalent bonding interactions. Moreover, in the presence of a photosensitizer, visible light energy is the only fuel source that is needed to drive the unidirectional molecular translation, making it feasible to repeat the operation numerous times without the buildup of byproducts.
Interrelationship Among Common Medical Complications After Acute Stroke: Pneumonia Plays an Important Role
Stroke; a Journal of Cerebral Circulation. Oct, 2013 | Pubmed ID: 24178914
Medical complications are common among patients with stroke. However, little is known about the potential interrelationship among them. In the present study, we aimed to investigate the association between common in-hospital medical complications after acute ischemic stroke (AIS) and spontaneous intracerebral hemorrhage (ICH).
The Journal of Rheumatology. Nov, 2013 | Pubmed ID: 24187097
To evaluate the clinical characteristics of systemic lupus erythematosus (SLE)-induced abdominal pain in a cohort in South China and identify the risk factors for SLE-induced abdominal pain.
Major Hepatectomy Is a Safe Modality for the Treatment of Intrahepatic Cholangiocarcinoma in Selected Patients Complicated with Cirrhosis
Journal of Gastrointestinal Surgery : Official Journal of the Society for Surgery of the Alimentary Tract. Nov, 2013 | Pubmed ID: 24222320
The objective of this paper is to evaluate the perioperative outcomes of major hepatectomy for intrahepatic cholangiocarcinoma (ICC) in patients with cirrhosis.
EXTRACTION, PURIFICATION, AND CHARACTERIZATION OF A TRYPSIN INHIBITOR FROM COWPEA SEEDS (Vigna Unguiculata)
Preparative Biochemistry & Biotechnology. Jan, 2014 | Pubmed ID: 24117148
Protease inhibitors against trypsin were extracted from cowpea seeds, purified, and characterized. After the seed powder was defatted with hexane, the cowpea trypsin inhibitor (CpTI) was extracted with 0.15 M NaCl for 30 min. The crude extracts were then heated at 90°C for 10 min, followed by precipitation with 40-65% saturation ammonium sulfate, by which the protein purity increased approximately 15-fold. The CpTI had approximate 88-fold and 186-fold purification after anion-exchange chromatography (Super-Q) and gel filtration (Sephadex G-200), respectively. A broad band of the purified CpTI on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) indicates a degree of heterogeneity and partial denaturation of CpTI, having a molecular mass of ∼8000 kD. Multiple peaks between 7451 and 8898 by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectroscopy also suggest heterogeneity. The purified CpTI was stable at 90°C for 60 min, pH 5-10, and 0-3.0% of NaCl. The purification method described here can be used to obtain highly purified CpTI for its studies such as risk assessment of CpTI genetically modified foods.
In Vitro Digestion Combined with Cellular Assay to Determine the Antioxidant Activity in Chinese Bayberry (Myrica Rubra Sieb. Et Zucc.) Fruits: A Comparison with Traditional Methods
Food Chemistry. Mar, 2014 | Pubmed ID: 24176355
The traditional method of chemical extraction (i.e., extracts), combined with chemical antioxidant activity assays cannot assess the real antioxidant activity. In vitro digestion (i.e., digesta) with a cellular antioxidant activity (CAA) assay was developed for the determination of antioxidant activity in Chinese bayberry fruits. In this study, pretreatment methods were studied and the results showed that digesta had more free phenolic acids (FPA) but less total phenolic content (TPC) and total anthocyanin content (TAC) than extracts. Antioxidant activity assays, including ABTS, FRAP, DPPH, ORAC and CAA, were compared. Digesta had lower ABTS, FRAP and DPPH values but higher CAA values than extracts. FPA were better correlated with the chemical antioxidant assays in digesta. The correlations were high between TPC and CAA values in digesta (R(2)=0.96) but not extracts (R(2)=0.58). Higher correlations were also obtained between CAA and chemical assays in digesta.