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Find video protocols related to scientific articles indexed in Pubmed.
Production of Water-Soluble Few-Layer Graphene Mesosheets by Dry Milling with Hydrophobic Drug.
Langmuir
PUBLISHED: 11-20-2014
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A novel, fast and easy mechano-chemistry-based (dry milling) method has been developed to exfoliate graphene with hydrophobic drugs generating few layer graphene mesosheets (< 10 nm in thickness and ~ 1 µm in width). The electronic properties of the graphitic structure were partially preserved after the milling treatment compared to Graphene Oxide (GO) prepared by Hummers' method. Several characterization techniques such as thermogravimetric analysis (TGA), Raman spectroscopy, atomic force microscopy (AFM), Electron Microscopy (EM) and molecular dynamics simulation were used to characterize this material. The drug-exfoliated mesosheets were pharmacologically inactive offering a new approach for making water-soluble few-layer graphene mesosheets upon dry milling with hydrophobic drugs, mainly used as exfoliating agents.
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Peripheral ?-Defensins 1 and 2 are Elevated in Alzheimer's Disease.
J. Alzheimers Dis.
PUBLISHED: 11-20-2014
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Biomarkers enabling the preclinical identification of Alzheimer's disease (AD) remain one of the major unmet challenges in the field. The blood cellular fractions offer a viable alternative to current cerebrospinal fluid and neuroimaging modalities. The current study aimed to replicate our earlier reports of altered binding within the AD-affected blood cellular fraction to copper-loaded immobilized metal affinity capture (IMAC) arrays. IMAC and anti-amyloid-? (A?) antibody arrays coupled with mass spectrometry were used to analyze blood samples collected from 218 participants from within the AIBL Study of Aging. Peripheral A? was fragile and prone to degradation in the AIBL samples, even when stored at -80°C. IMAC analysis of the AIBL samples lead to the isolation and identification of alpha-defensins 1 and 2 at elevated levels in the AD periphery, validating earlier findings. Alpha-defensins 1 and 2 were elevated in AD patients indicating that an inflammatory phenotype is present in the AD periphery; however, peripheral A? levels are required to supplement their prognostic power.
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Selection of aptamers specific for glycated hemoglobin and total hemoglobin using on-chip SELEX.
Lab Chip
PUBLISHED: 11-20-2014
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Blood glycated hemoglobin (HbA1c) levels reflecting average glucose concentrations over the past three months are fundamental for the diagnosis, monitoring, and risk assessment of diabetes. It has been hypothesized that aptamers, which are single-stranded DNAs or RNAs that demonstrate high affinity to a large variety of molecules ranging from small drugs, metabolites, or proteins, could be used for the measurement of HbA1c. Aptamers are selected through an in vitro process called systematic evolution of ligands by exponential enrichment (SELEX), and they can be chemically synthesized with high reproducibility at relatively low costs. This study therefore aimed to select HbA1c- and hemoglobin (Hb)-specific single-stranded DNA aptamers using an on-chip SELEX protocol. A microfluidic SELEX chip was developed to continuously and automatically carry out multiple rounds of SELEX to screen specific aptamers for HbA1c and Hb. HbA1c and Hb were first coated onto magnetic beads. Following several rounds of selection and enrichment with a randomized 40-mer DNA library, specific oligonucleotides were selected. The binding specificity and affinity were assessed by competitive and binding assays. Using the developed microfluidic system, the incubation and partitioning times were greatly decreased, and the entire process was shortened dramatically. Both HbA1c- and Hb-specific aptamers selected by the microfluidic system showed high specificity and affinity (dissociation constant, Kd = 7.6 ± 3.0 nM and 7.3 ± 2.2 nM for HbA1c and Hb, respectively). With further refinements in the assay, these aptamers may replace the conventional antibodies for in vitro diagnostics applications in the near future.
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Improving the carrier balance of light-emitting electrochemical cells based on ionic transition metal complexes.
Dalton Trans
PUBLISHED: 11-20-2014
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Recently, solid-state light-emitting electrochemical cells (LECs) based on ionic transition metal complexes (iTMCs) have attracted much research interest since they have the advantages of a simple device structure, a low operation voltage and compatibility with air-stable electrodes. These properties enable LECs to be cost-effective, versatile and power-efficient organic light-emitting sources. However, it is generally not easy to modify the molecular structure to achieve balanced carrier mobilities without altering the photoluminescence quantum yield of the iTMC. Furthermore, the carrier balance and the consequent device efficiency of single-layered LECs would not be easy to optimize since no carrier injection and transport layers can be used. In this perspective, some reported techniques to improve carrier balance of LECs based on iTMCs are described and reviewed. The importance and impact of these studies are highlighted. The effects on device lifetime and turn-on time because of employing these techniques to improve the carrier balance are also discussed. This perspective concludes that even with electrochemically doped layers, improving the carrier balance of LECs would be required for realizing efficient electroluminescent emission from simple-structure organic light-emitting sources.
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Real-time Cytotoxicity Assays in Human Whole Blood.
J Vis Exp
PUBLISHED: 11-20-2014
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A live cell-based whole blood cytotoxicity assay (WCA) that allows access to temporal information of the overall cell cytotoxicity is developed with high-throughput cell positioning technology. The targeted tumor cell populations are first preprogrammed to immobilization into an array format, and labeled with green fluorescent cytosolic dyes. Following the cell array formation, antibody drugs are added in combination with human whole blood. Propidium iodide (PI) is then added to assess cell death. The cell array is analyzed with an automatic imaging system. While cytosolic dye labels the targeted tumor cell populations, PI labels the dead tumor cell populations. Thus, the percentage of target cancer cell killing can be quantified by calculating the number of surviving targeted cells to the number of dead targeted cells. With this method, researchers are able to access time-dependent and dose-dependent cell cytotoxicity information. Remarkably, no hazardous radiochemicals are used. The WCA presented here has been tested with lymphoma, leukemia, and solid tumor cell lines. Therefore, WCA allows researchers to assess drug efficacy in a highly relevant ex vivo condition.
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Epidemiology of Internet Behaviors and Addiction Among Adolescents in Six Asian Countries.
Cyberpsychol Behav Soc Netw
PUBLISHED: 11-19-2014
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Abstract Internet addiction has become a serious behavioral health problem in Asia. However, there are no up-to-date country comparisons. The Asian Adolescent Risk Behavior Survey (AARBS) screens and compares the prevalence of Internet behaviors and addiction in adolescents in six Asian countries. A total of 5,366 adolescents aged 12-18 years were recruited from six Asian countries: China, Hong Kong, Japan, South Korea, Malaysia, and the Philippines. Participants completed a structured questionnaire on their Internet use in the 2012-2013 school year. Internet addiction was assessed using the Internet Addiction Test (IAT) and the Revised Chen Internet Addiction Scale (CIAS-R). The variations in Internet behaviors and addiction across countries were examined. The overall prevalence of smartphone ownership is 62%, ranging from 41% in China to 84% in South Korea. Moreover, participation in online gaming ranges from 11% in China to 39% in Japan. Hong Kong has the highest number of adolescents reporting daily or above Internet use (68%). Internet addiction is highest in the Philippines, according to both the IAT (5%) and the CIAS-R (21%). Internet addictive behavior is common among adolescents in Asian countries. Problematic Internet use is prevalent and characterized by risky cyberbehaviors.
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Effect of copper oxide oxidation state on the polymer-based solar cell buffer layers.
ACS Appl Mater Interfaces
PUBLISHED: 11-19-2014
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Transporting buffer layers are important components of the polymer-based organic photovoltaic devices. In this study, we have investigated the effects of the oxidation state in copper oxide based buffer layer in conjunction to its role in device performance. We have shown that variation in the oxidation state affects the band alignment and built-in voltage of the device, therefore, leading to variation in device performance. Specifically, the fully oxidized copper oxide buffer layer has a valence band position at 5.12 eV, much closer to the highest occupied molecular orbital of Poly(3-hexylthiophene-2,5-diyl) (P3HT) (~5.2 eV), giving a best fill factor and efficiency at 57% and 4.06%, respectively. Lastly, we also demonstrate significant enhancement in device stability, with power conversion efficiency maintained at 75% of the original value even after 40 days, and propose a strategy in recovering the device performance based on the observed property of the oxide buffer layer.
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Results of Operative Correction of Grade IIB Tibialis Posterior Tendon Dysfunction.
Foot Ankle Int
PUBLISHED: 11-19-2014
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The prevalence of tibialis posterior tendon dysfunction (PTTD) is estimated to be as high as 3% to 4% in Western populations, and it is one of the most commonly misdiagnosed conditions of the foot and ankle.
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Phage Display-Mediated Discovery of Novel Tyrosinase-Targeting Tetrapeptide Inhibitors Reveals the Significance of N-Terminal Preference of Cysteine Residues and Their Functional Sulfur Atom.
Mol. Pharmacol.
PUBLISHED: 11-19-2014
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Tyrosinase, a key copper-containing enzyme involved in melanin biosynthesis, is closely associated with hyperpigmentation disorders, cancer, and neurodegenerative diseases, and as such, it is an essential target in medicine and cosmetics. Known tyrosinase inhibitors possess adverse side effects, and there are no safety regulations, so there is the necessity to develop new inhibitors with fewer side effects and less toxicity. Peptides are exquisitely specific to their in vivo targets, with high potencies and relatively few off-target side effects. Thus, we systematically and comprehensively investigated the tyrosinase-inhibitory abilities of N- and C-terminal cysteine/tyrosine-constrained tetrapeptides by constructing a phage-display random tetrapeptide library and conducting computational molecular docking studies on novel tyrosinase tetrapeptide inhibitors. We found that N-terminal cysteine-constrained tetrapeptides exhibited the most potent tyrosinase-inhibitory abilities. The positional preference of cysteine residues at the N-terminus in the tetrapeptides significantly contributed to their tyrosinase-inhibitory function. The sulfur atom in cysteine moieties of N- and C-terminal cysteine-constrained tetrapeptides coordinated with copper ions which then tightly blocked substrate-binding sites. N- and C-terminal tyrosine-constrained tetrapeptides functioned as competitive inhibitors against mushroom tyrosinase by using the phenol ring of tyrosine to stack with the imidazole ring of His263, thus competing for the substrate-binding site. The N-terminal cysteine-constrained tetrapeptide, CRVI, exhibited the strongest tyrosinase-inhibitory potency (with an IC50 of 2.7 ± 0.5 ?M) which was superior to those of the known tyrosinase inhibitors (arbutin and kojic acid) and outperformed kojic acid-tripeptides, mimosine-FFY, and short-sequence oligopeptides at inhibiting mushroom tyrosinase.
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Osteoporosis increases subsequent risk of gallstone: a nationwide population-based cohort study in Taiwan.
BMC Gastroenterol
PUBLISHED: 11-18-2014
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BackgroundOsteopontin (OPN) is a pro-inflammatory cytokine which is expressed in various tissues. It participates in the bone remodeling process and stimulates bone resorption by osteoclasts. It is also a core protein of cholesterol gallstones. We hypothesized osteoporotic patients might have higher risk in developing gallstones and conducted a population-based study to examine the risk of developing gallstone in osteoporotic patients in Taiwan.MethodsA total of 1,638 patients diagnosed with osteoporosis between 2003 and 2005 were identified in the National Health Insurance Research Database. A comparison cohort without osteoporosis (n =6,552) was randomly matched to each osteoporosis patient at a ratio of 4: 1 based on age and sex. A Cox proportional-hazards regression analysis was performed to evaluate the 5-year gallstone-free survival rates for the 2 cohorts.ResultsDuring the 5-year follow-up period, 114 and 311 cases of gallstone occurred in the osteoporosis and comparison cohorts, respectively. After adjusting for the confounders, the Cox regression analysis of the risk of gallstone in the osteoporosis and comparison cohorts yielded a hazard ratio of 1.35 (95% confidence interval: 1.07 - 1.69; p < 0 .01).ConclusionPatients with osteoporosis in Taiwan have a higher risk of developing gallstone than the general population.
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H19 long noncoding RNA controls the mRNA decay promoting function of KSRP.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 11-12-2014
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Long noncoding RNAs (lncRNAs) interact with protein factors to regulate different layers of gene expression transcriptionally or posttranscriptionally. Here we report on the functional consequences of the unanticipated interaction of the RNA binding protein K homology-type splicing regulatory protein (KSRP) with the H19 lncRNA (H19). KSRP directly binds to H19 in the cytoplasm of undifferentiated multipotent mesenchymal C2C12 cells, and this interaction favors KSRP-mediated destabilization of labile transcripts such as myogenin. AKT activation induces KSRP dismissal from H19 and, as a consequence, myogenin mRNA is stabilized while KSRP is repurposed to promote maturation of myogenic microRNAs, thus favoring myogenic differentiation. Our data indicate that H19 operates as a molecular scaffold that facilitates effective association of KSRP with myogenin and other labile transcripts, and we propose that H19 works with KSRP to optimize an AKT-regulated posttranscriptional switch that controls myogenic differentiation.
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Resveratrol post-transcriptionally regulates pro-inflammatory gene expression via regulation of KSRP RNA binding activity.
Nucleic Acids Res.
PUBLISHED: 10-28-2014
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Resveratrol shows beneficial effects in inflammation-based diseases like cancer, cardiovascular and chronic inflammatory diseases. Therefore, the molecular mechanisms of the anti-inflammatory resveratrol effects deserve more attention. In human epithelial DLD-1 and monocytic Mono Mac 6 cells resveratrol decreased the expression of iNOS, IL-8 and TNF-? by reducing mRNA stability without inhibition of the promoter activity. Shown by pharmacological and siRNA-mediated inhibition, the observed effects are SIRT1-independent. Target-fishing and drug responsive target stability experiments showed selective binding of resveratrol to the RNA-binding protein KSRP, a central post-transcriptional regulator of pro-inflammatory gene expression. Knockdown of KSRP expression prevented resveratrol-induced mRNA destabilization in human and murine cells. Resveratrol did not change KSRP expression, but immunoprecipitation experiments indicated that resveratrol reduces the p38 MAPK-related inhibitory KSRP threonine phosphorylation, without blocking p38 MAPK activation or activity. Mutation of the p38 MAPK target site in KSRP blocked the resveratrol effect on pro-inflammatory gene expression. In addition, resveratrol incubation enhanced KSRP-exosome interaction, which is important for mRNA degradation. Finally, resveratrol incubation enhanced its intra-cellular binding to the IL-8, iNOS and TNF-? mRNA. Therefore, modulation of KSRP mRNA binding activity and, thereby, enhancement of mRNA degradation seems to be the common denominator of many anti-inflammatory effects of resveratrol.
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Impact of constitution of the terthiophene-vinylene conjugated side chain on the optical and photovoltaic properties of two-dimensional polythiophenes.
Phys Chem Chem Phys
PUBLISHED: 10-22-2014
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The effects of the spatial arrangement of the conjugated side chains of two-dimensional polymers on their optical, electrochemical, molecular-packing, and photovoltaic characteristics were investigated. Accordingly, novel polythiophenes with horizontally () and vertically () grafted terthiophene-vinylene (TTV) conjugated side chains were synthesized that display two and one UV-vis peaks, respectively; the difference is due to the different constitutions of the conjugated side-chains. Because the spatial arrangement affects the molecular self-assembly, shows stronger crystallinity than , which enhances the charge mobility in devices. Moreover, has a lower HOMO energy level (-5.49 eV) than (-5.40 eV). Bulk heterojunction solar cells fabricated from /PC71BM and /PC71BM exhibit power conversion efficiencies of 4.75% and 4.00%, respectively, and Voc values of 800 and 730 mV, respectively, under AM1.5G illumination (100 mW cm(-2)). Thus, the architecture of the TTV conjugated side chains affects the optical, electrochemical, and photovoltaic properties; this study provides more ideas for improving 2-D conjugated polymers for semiconductor devices.
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A mechanistic study on urine retention in d-amphetamine addicts.
Chin J Physiol
PUBLISHED: 09-24-2014
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Chronic amphetamine intake leads to neurogenic bladder and chronic urinary retention. The mechanism underlying persistent urinary retention is unclear. The pelvic-urethral reflex (PUR) is essential for the urethra to develop sufficient resistance to maintain urine continence, an important function of the urinary system. Recent studies on PUR activities have indicated that repetitive/tetanic stimulation of the pelvic afferent fibers induces spinal reflex potentiation (SRP) in PUR activities, which further increases urinary retention. In this study, results showed that test stimulation (TS, 1/30 Hz) evoked a baseline reflex activity, while repetitive stimulation (RS, 1 Hz) induced reflex potentiation in the external urethral sphincter. Intrathecal d-amphetamine (AMPH, 30 ?M) did not but higher AMPH concentration (100 ?M) induced SRP in TS-induced reflex activity. H89 (10 ?M, a protein kinase A inhibitor), but not chelerythrine chloride (CTC, 10 ?M, a protein kinase C inhibitor), prevented the 100 ?M AMPH-elicited SRP. At 30 ?M, forskolin, an activator of adenylyl cyclase, elicited SRP. The co-administration of 10 ?M forskolin and 30 ?M AMPH induced SRP in TS-induced reflex activity. These results implied that the repetitive/tetanic stimulation of the pelvic afferent fibers could induce SRP in PUR activities, so that the urethra can produce sufficient resistance and played a significant role in urinary retention. Findings in this study demonstrated that amphetamine could induce bladder dysfunction by triggering protein kinase A activation, and provide a practical basis for the development of treatment for amphetamine-associated urinary retention.
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The impacts of migraine and anxiety disorders on painful physical symptoms among patients with major depressive disorder.
J Headache Pain
PUBLISHED: 09-23-2014
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No study has simultaneously investigated the impacts of migraine and anxiety disorders on painful physical symptoms (PPS) among patients with major depressive disorder (MDD). The study aimed to investigate this issue.
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Palmitic Acid-Induced Neuron Cell Cycle G2/M Arrest and Endoplasmic Reticular Stress through Protein Palmitoylation in SH-SY5Y Human Neuroblastoma Cells.
Int J Mol Sci
PUBLISHED: 08-29-2014
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Obesity-related neurodegenerative diseases are associated with elevated saturated fatty acids (SFAs) in the brain. An increase in SFAs, especially palmitic acid (PA), triggers neuron cell apoptosis, causing cognitive function to deteriorate. In the present study, we focused on the specific mechanism by which PA triggers SH-SY5Y neuron cell apoptosis. We found that PA induces significant neuron cell cycle arrest in the G2/M phase in SH-SY5Y cells. Our data further showed that G2/M arrest is involved in elevation of endoplasmic reticular (ER) stress according to an increase in p-eukaryotic translation inhibition factor 2?, an ER stress marker. Chronic exposure to PA also accelerates beta-amyloid accumulation, a pathological characteristic of Alzheimer's disease. Interestingly, SFA-induced ER stress, G2/M arrest and cell apoptosis were reversed by treatment with 2-bromopalmitate, a protein palmitoylation inhibitor. These findings suggest that protein palmitoylation plays a crucial role in SFA-induced neuron cell cycle G2/M arrest, ER stress and apoptosis; this provides a novel strategy for preventing SFA-induced neuron cell dysfunction.
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Extremely low-frequency electromagnetic fields cause G1 phase arrest through the activation of the ATM-Chk2-p21 pathway.
PLoS ONE
PUBLISHED: 08-11-2014
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In daily life, humans are exposed to the extremely low-frequency electromagnetic fields (ELF-EMFs) generated by electric appliances, and public concern is increasing regarding the biological effects of such exposure. Numerous studies have yielded inconsistent results regarding the biological effects of ELF-EMF exposure. Here we show that ELF-EMFs activate the ATM-Chk2-p21 pathway in HaCaT cells, inhibiting cell proliferation. To present well-founded results, we comprehensively evaluated the biological effects of ELF-EMFs at the transcriptional, protein, and cellular levels. Human HaCaT cells from an immortalized epidermal keratinocyte cell line were exposed to a 1.5 mT, 60 Hz ELF-EMF for 144 h. The ELF-EMF could cause G1 arrest and decrease colony formation. Protein expression experiments revealed that ELF-EMFs induced the activation of the ATM/Chk2 signaling cascades. In addition, the p21 protein, a regulator of cell cycle progression at G1 and G2/M, exhibited a higher level of expression in exposed HaCaT cells compared with the expression of sham-exposed cells. The ELF-EMF-induced G1 arrest was diminished when the CHK2 gene expression (which encodes checkpoint kinase 2; Chk2) was suppressed by specific small interfering RNA (siRNA). These findings indicate that ELF-EMFs activate the ATM-Chk2-p21 pathway in HaCaT cells, resulting in cell cycle arrest at the G1 phase. Based on the precise control of the ELF-EMF exposure and rigorous sham-exposure experiments, all transcriptional, protein, and cellular level experiments consistently supported the conclusion. This is the first study to confirm that a specific pathway is triggered by ELF-EMF exposure.
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The pathological effects of CCR2+ inflammatory monocytes are amplified by an IFNAR1-triggered chemokine feedback loop in highly pathogenic influenza infection.
J. Biomed. Sci.
PUBLISHED: 07-28-2014
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BackgroundHighly pathogenic influenza viruses cause high levels of morbidity, including excessive infiltration of leukocytes into the lungs, high viral loads and a cytokine storm. However, the details of how these pathological features unfold in severe influenza infections remain unclear. Accumulation of Gr1¿+¿CD11b¿+¿myeloid cells has been observed in highly pathogenic influenza infections but it is not clear how and why they accumulate in the severely inflamed lung. In this study, we selected this cell population as a target to investigate the extreme inflammatory response during severe influenza infection.ResultsWe established H1N1 IAV-infected mouse models using three viruses of varying pathogenicity and noted the accumulation of a defined Gr1¿+¿CD11b¿+¿myeloid population correlating with the pathogenicity. Herein, we reported that CCR2+ inflammatory monocytes are the major cell compartments in this population. Of note, impaired clearance of the high pathogenicity virus prolonged IFN expression, leading to CCR2+ inflammatory monocytes amplifying their own recruitment via an interferon-¿/ß receptor 1 (IFNAR1)-triggered chemokine loop. Blockage of IFNAR1-triggered signaling or inhibition of viral replication by Oseltamivir significantly suppresses the expression of CCR2 ligands and reduced the influx of CCR2+ inflammatory monocytes. Furthermore, trafficking of CCR2+ inflammatory monocytes from the bone marrow to the lung was evidenced by a CCR2-dependent chemotaxis. Importantly, leukocyte infiltration, cytokine storm and expression of iNOS were significantly reduced in CCR2¿/¿ mice lacking infiltrating CCR2+ inflammatory monocytes, enhancing the survival of the infected mice.ConclusionsOur results indicated that uncontrolled viral replication leads to excessive production of inflammatory innate immune responses by accumulating CCR2+ inflammatory monocytes, which contribute to the fatal outcomes of high pathogenicity virus infections.
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N-3 polyunsaturated fatty acids decrease levels of doxorubicin-induced reactive oxygen species in cardiomyocytes -- involvement of uncoupling protein UCP2.
J. Biomed. Sci.
PUBLISHED: 07-22-2014
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BackgroundUse of the chemotherapeutic drug doxorubicin (DOX) is associated with serious cardiotoxicity, as it increases levels of reactive oxygen species (ROS). N-3 polyunsaturated fatty acid dietary supplements can be of benefit to patients undergoing cancer therapy. The aims of this study were to determine whether DOX-induced cardiotoxicity is related to mitochondrial uncoupling proteins and whether eicosapentaenoic acid (EPA, C20:5 n-3) or docosahexaenoic acid (DHA, C22:6 n-3) affects DOX-induced cardiomyocyte toxicity.ResultsTreatment of H9C2 cells with DOX resulted in decreased cell viability and UCP2 expression. Treatment with 100 ¿M EPA or 50 ¿M DHA for 24 h resulted in a maximal mitochondria concentration of these fatty acids and increased UCP2 expression. Pretreatment with 100 ¿M EPA or 50 ¿M DHA prevented the DOX-induced decrease in UCP2 mRNA and protein levels, but these effects were not seen with EPA or DHA and DOX cotreatment. In addition, the DOX-induced increase in ROS production and subsequent mitochondrial membrane potential change (¿¿) were significantly attenuated by pretreatment with EPA or DHA.ConclusionEPA or DHA pre-treatment inhibits the DOX-induced decrease in UCP2 expression, increase in ROS production, and subsequent mitochondrial membrane potential change that contribute to the cardiotoxicity of DOX.
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The reduced autophagic response by oxidative stress in angiotensin II-induced hypertrophic H9C2 cells causes more apoptotic cell death.
Exp. Biol. Med. (Maywood)
PUBLISHED: 07-10-2014
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Autophagy is an important process in the pathogenesis of cardiovascular diseases, and angiotensin II (Ang II) plays a causative role in the induction of cardiomyocyte autophagy. The purpose of this study was to explore whether, under conditions of oxidative stress, levels and types of cell death were different in untreated and Ang II-treated cardiomyocytes (H9C2 cells). Treatment with 20?µM Ang II induced cardiac hypertrophy in H9C2 cells, with increased expression of the hypertrophic markers c-Fos, ß-myosin heavy chain, atrial natriuretic factor (ANF), and brain natriuretic factor (BNF). Under normal conditions, there was no difference in the levels of autophagic vacuoles and apoptotic bodies in untreated and Ang II-treated H9C2 cells. However, oxidative stress generated by 100?µM H2O2 triggered autophagy in untreated control cells, but had a reduced effect in Ang II-induced hypertrophic cells, resulting in more cell death, and this was associated with a decrease in connexin 43 expression. Blocking this autophagic response with 3-methyladenine resulted in a significant increase in cell death and apoptosis of H9C2 cells but did not significantly affect the response of Ang II-treated cells. The autophagic response to 100?µM H2O2 provides a survival advantage for cells and this is reduced by Ang II treatment.
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Uracil DNA glycosylase BKRF3 contributes to Epstein-Barr virus DNA replication through physical interactions with proteins in viral DNA replication complex.
J. Virol.
PUBLISHED: 05-28-2014
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Epstein-Barr virus (EBV) BKRF3 shares sequence homology with members of the uracil-N-glycosylase (UNG) protein family and has DNA glycosylase activity. Here, we explored how BKRF3 participates in the DNA replication complex and contributes to viral DNA replication. Exogenously expressed Flag-BKRF3 was distributed mostly in the cytoplasm, whereas BKRF3 was translocated into the nucleus and colocalized with the EBV DNA polymerase BALF5 in the replication compartment during EBV lytic replication. The expression level of BKRF3 increased gradually during viral replication, coupled with a decrease of cellular UNG2, suggesting BKRF3 enzyme activity compensates for UNG2 and ensures the fidelity of viral DNA replication. In immunoprecipitation-Western blotting, BKRF3 was coimmuno-precipitated with BALF5, the polymerase processivity factor BMRF1, and the immediate-early transactivator Rta. Coexpression of BMRF1 appeared to facilitate the nuclear targeting of BKRF3 in immunofluorescence staining. Residues 164 to 255 of BKRF3 were required for interaction with Rta and BALF5, whereas residues 81 to 166 of BKRF3 were critical for BMRF1 interaction in glutathione S-transferase (GST) pulldown experiments. Viral DNA replication was defective in cells harboring BKRF3 knockout EBV bacmids. In complementation assays, the catalytic mutant BKRF3(Q90L,D91N) restored viral DNA replication, whereas the leucine loop mutant BKRF3(H213L) only partially rescued viral DNA replication, coupled with a reduced ability to interact with the viral DNA polymerase and Rta. Our data suggest that BKRF3 plays a critical role in viral DNA synthesis predominantly through its interactions with viral proteins in the DNA replication compartment, while its enzymatic activity may be supplementary for uracil DNA glycosylase (UDG) function during virus replication.
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Triggers of suicide ideation and protective factors of actually executing suicide among first onset cases in older psychiatric outpatients: a qualitative study.
BMC Psychiatry
PUBLISHED: 05-21-2014
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BackgroundSuicide is a global issue among the elderly, but few studies have explored the experiences of suicide ideation in older Asian psychiatric outpatients.MethodOlder psychiatric outpatients (N¿=¿24) were recruited by convenience from one medical centre and one regional hospital in northern Taiwan. Participants were recruited if they met these inclusion criteria: 1) ¿65 years old, 2) without severe cognitive deficit, 3) outpatients in the psychiatric clinics at the selected hospitals, and 4) self-reported first episode of suicidal ideation within the previous year. Data were collected in individual interviews using a semi-structured guide and analysed by content analysis.ResultsSuicide ideation was triggered by illness and physical discomfort, conflicts with family members/friends, illness of family members, death of family members/friends, and loneliness. Participants¿ reasons for not executing suicide were family members¿ and friends¿ support, receiving treatment, finding a way to shift their attention, fear of increasing pressure on one¿s children, religious beliefs, and not knowing how to execute suicide.ConclusionUnderstanding these identified triggers of suicide ideation may help psychiatrists open a channel for conversation with their elderly clients and more readily make their diagnosis. Understanding these identified protective factors against executing suicide can help psychiatrists not only treat depression, but also enhance protective factors for their clients.
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The association between internet addiction and psychiatric co-morbidity: a meta-analysis.
BMC Psychiatry
PUBLISHED: 05-21-2014
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This study evaluates the association between Internal Addiction (IA) and psychiatric co-morbidity in the literature.
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Chicken essence improves exercise performance and ameliorates physical fatigue.
Nutrients
PUBLISHED: 05-04-2014
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Chicken essence (CE) is a liquid nutritional supplement made from cooking whole chickens. In traditional Chinese medicine, CE is used to support health, promote healing, increase metabolism, and relieve fatigue. However, few studies have examined the effect of CE on exercise performance and physical fatigue. We aimed to evaluate the potential beneficial effects of CE on fatigue and ergogenic functions following physical challenge in mice. Male ICR mice were divided into four groups to receive vehicle or CE by oral gavage at 0, 845, 1690, or 4225 mg/kg/day for 4 weeks. Exercise performance and anti-fatigue function were evaluated by forelimb grip strength, exhaustive swimming time, and levels of physical fatigue-related biomarkers serum lactate, ammonia, glucose, and creatine kinase (CK) after physical challenge. CE supplementation dose-dependently elevated endurance and grip strength. CE supplementation significantly decreased lactate, ammonia, and CK levels after physical challenge. Tissue glycogen content, an important energy source for exercise, was significantly increased with CE supplementation. In addition, CE supplementation had few subchronic toxic effects. The supplementation with CE can have a wide spectrum of bioactivities on health promotion, performance improvement and anti-fatigue.
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KSRP and MicroRNA 145 are negative regulators of lipolysis in white adipose tissue.
Mol. Cell. Biol.
PUBLISHED: 04-14-2014
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White adipose tissue (WAT) releases fatty acids from stored triacylglycerol for an energy source. Here, we report that targeted deletion of KH-type splicing regulatory protein (KSRP), an RNA-binding protein that regulates gene expression at multiple levels, enhances lipolysis in epididymal WAT (eWAT) because of the upregulation of genes promoting lipolytic activity. Expression of microRNA 145 (miR-145) is decreased because of impaired primary miR-145 processing in Ksrp(-/-) eWAT. We show that miR-145 directly targets and represses Foxo1 and Cgi58, activators of lipolytic activity, and forced expression of miR-145 attenuates lipolysis. This study reveals a novel in vivo function of KSRP in controlling adipose lipolysis through posttranscriptional regulation of miR-145 expression.
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KSRP ablation enhances brown fat gene program in white adipose tissue through reduced miR-150 expression.
Diabetes
PUBLISHED: 04-10-2014
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Brown adipose tissue oxidizes chemical energy for heat generation and energy expenditure. Promoting brown-like transformation in white adipose tissue (WAT) is a promising strategy for combating obesity. Here, we find that targeted deletion of KH-type splicing regulatory protein (KSRP), an RNA-binding protein that regulates gene expression at multiple levels, causes a reduction in body adiposity. The expression of brown fat-selective genes is increased in subcutaneous/inguinal WAT (iWAT) of Ksrp(-/-) mice because of the elevated expression of PR domain containing 16 and peroxisome proliferator-activated receptor gamma coactivator 1?, which are key regulators promoting the brown fat gene program. The expression of microRNA (miR)-150 in iWAT is decreased due to impaired primary miR-150 processing in the absence of KSRP. We show that miR-150 directly targets and represses Prdm16 and Ppargc1a, and that forced expression of miR-150 attenuates the elevated expression of brown fat genes caused by KSRP deletion. This study reveals the in vivo function of KSRP in controlling brown-like transformation of iWAT through post-transcriptional regulation of miR-150 expression.
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Development of a dietary induced metabolic syndrome model using miniature pigs-invovlement of ampk and sirt1.
Eur. J. Clin. Invest.
PUBLISHED: 04-09-2014
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During the progression of the metabolic syndrome (MetS), cardiovascular diseases (CVD) appear clinically in many individuals and cause death. As a result, it is essential to set-up an optimal animal model to study the mechanism of MetS leading to CVD. SIRT1 and AMPK are the master regulators of lipid and carbohydrate metabolism. The objective of this study was to establish a miniature pig model of Western diet-induced MetS and investigate the role of SIRT1/AMPK during MetS development.
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Malignant transformation in 5071 southern Taiwanese patients with potentially malignant oral mucosal disorders.
BMC Oral Health
PUBLISHED: 04-08-2014
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Oral cancers can be preceded by clinically evident oral potentially malignant disorders (OPMDs). The current study evaluated the rate and the time of malignant transformation in the various OPMDs in a cohort of patients from southern Taiwan. Parameters possibly indicative for malignant transformation of OPMDs, such as epidemiological and etiological factors, and clinical and histopathological features were also described.
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Role of KSRP in control of type I interferon and cytokine expression.
J. Interferon Cytokine Res.
PUBLISHED: 04-05-2014
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Cytokines and chemokines are key participants in pathways that drive inflammatory, immune, and other cellular responses to exogenous insults such as infection, trauma, and physiological stress. Persistent and aberrant expression of these factors has been linked to autoimmune, degenerative, and neoplastic diseases. Consequently, cytokine and chemokine expression is tightly governed at each level of gene regulation. Recent studies have demonstrated a role for KH-type splicing regulatory protein (KSRP) in curtailing cytokine and chemokine expression through transcriptional and post-transcriptional mechanisms, including promotion of microRNA maturation. Understanding the role of KSRP in cytokine mRNA metabolism should identify promising targets for the modulation of immune and inflammatory responses.
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Adiponectin receptor 1 overexpression reduces lipid accumulation and hypertrophy in the heart of diet-induced obese mice - possible involvement of oxidative stress and autophagy.
Endocr. Res.
PUBLISHED: 03-28-2014
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Abstract Background: Studies show that adiponectin and its receptors (AdipoR1 and 2) play important roles in regulating glucose and lipid metabolism in mice. Obesity, type II diabetes and cardiovascular disease are highly correlated with downregulated adiponectin signaling; however, research has not clarified the functions of AdipoR1 in vivo.
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KSRP controls pleiotropic cellular functions.
Semin. Cell Dev. Biol.
PUBLISHED: 03-17-2014
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The single-strand-RNA binding protein KSRP is able to negatively regulate gene expression operating with at least two distinct and integrated postranscriptional mechanisms: (i) by promoting decay of unstable mRNAs and (ii) by favoring maturation from precursors of select microRNAs (miRNAs) including the prototypical tumor suppressor let-7. Studies performed in primary and cultured cells as well as in mice proved that the ability of KSRP to integrate different levels of gene expression is required for proper immune response, lipid metabolism, cell-fate decisions, tissue regeneration, and DNA damage response.
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Dual thermo- and pH-responsive zwitterionic sulfobataine copolymers for oral delivery system.
Macromol Rapid Commun
PUBLISHED: 03-15-2014
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A novel oral delivery system consisting of thermoresponsive zwitterionic poly(sulfobetaine methacrylate) (PSBMA) and pH-responsive poly(2-(diisopropylamino)ethyl methacrylate) (PDPA) is synthesized via free radical polymerization. This copolymer can self-aggregate into nanoparticles via electrostatic attraction between ammonium cation and sulfo-anion of PSBMA and successfully encapsulate anticancer drug, curcumin (CUR), with highest loading content of 2.6% in the P(SBMA-co-DPA) nanoparticles. The stimuli-responsive phase transition behaviors of P(SBMA-co-DPA) copolymers at different pH buffer solution show pH-dependent upper critical solution temperature (UCST) attributed to the influence of protonation/deprotonation of the pH-responsive DPA segments. Through the delicate adjustment of the PSBMA/PDPA molar ratios, the stimuli-responsive phase transition could be suitable for physiological environment. The kinetic drug release profiles demonstrate that P(SBMA-co-DPA) nanoparticles have the potential as oral delivery carriers due to their effective release of entrapped drugs in the stimulated intestinal fluid and preventing the deterioration of drug in stimulated gastric fluid.
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Psychometric properties of the Revised Chen Internet Addiction Scale (CIAS-R) in Chinese adolescents.
J Abnorm Child Psychol
PUBLISHED: 03-04-2014
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The Revised Chen Internet Addiction Scale (CIAS-R) was developed to assess Internet addiction in Chinese populations, but its psychometric properties in adolescents have not been examined. This study aimed to evaluate the factor structure and psychometric properties of CIAS-R in Hong Kong Chinese adolescents. 860 Grade 7 to 13 students (38 % boys) completed the CIAS-R, the Young's Internet Addiction Test (IAT), and the Health of the Nation Outcome Scales for Children and Adolescents (HoNOSCA) in a survey. The prevalence of Internet addiction as assessed by CIAS-R was 18 %. High internal consistency and inter-item correlations were reported for the CIAS-R. Results from the confirmatory factor analysis suggested a four-factor structure of Compulsive Use and Withdrawal, Tolerance, Interpersonal and Health-related Problems, and Time Management Problems. Moreover, results of hierarchical multiple regression supported the incremental validity of the CIAS-R to predict mental health outcomes beyond the effects of demographic differences and self-reported time spent online. The CIAS is a reliable and valid measure of internet addiction problems in Hong Kong adolescents. Future study is warranted to validate the cutoffs of the CIAS-R for identification of adolescents with Internet use problems who may have mental health needs.
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Chemoenzymatic synthesis of sialosides containing C7-modified sialic acids and their application in sialidase substrate specificity studies.
Carbohydr. Res.
PUBLISHED: 02-20-2014
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Modifications at the glycerol side chain of sialic acid in sialosides modulate their recognition by sialic acid-binding proteins and sialidases. However, limited work has been focused on the synthesis and functional studies of sialosides with C7-modified sialic acids. Here we report chemical synthesis of C4-modified ManNAc and mannose and their application as sialic acid precursors in a highly efficient one-pot three-enzyme system for chemoenzymatic synthesis of ?2-3- and ?2-6-linked sialyl para-nitrophenyl galactosides in which the C7-hydroxyl group in sialic acid (N-acetylneuraminic acid, Neu5Ac, or 2-keto-3-deoxynonulosonic acid, Kdn) was systematically substituted by -F, -OMe, -H, and -N3 groups. Substrate specificity study of bacterial and human sialidases using the obtained sialoside library containing C7-modified sialic acids showed that sialosides containing C7-deoxy Neu5Ac were selective substrates for all bacterial sialidases tested but not for human NEU2. The information obtained from sialidase substrate specificity can be used to guide the design of new inhibitors that are selective against bacterial sialidases.
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Epstein-Barr virus BALF3 has nuclease activity and mediates mature virion production during the lytic cycle.
J. Virol.
PUBLISHED: 02-19-2014
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Epstein-Barr virus (EBV) lytic replication involves complex processes, including DNA synthesis, DNA cleavage and packaging, and virion egress. These processes require many different lytic gene products, but the mechanisms of their actions remain unclear, especially for DNA cleavage and packaging. According to sequence homology analysis, EBV BALF3, encoded by the third leftward open reading frame of the BamHI-A fragment in the viral genome, is a homologue of herpes simplex virus type 1 UL28. This gene product is believed to possess the properties of a terminase, such as nucleolytic activity on newly synthesized viral DNA and translocation of unit length viral genomes into procapsids. In order to characterize EBV BALF3, the protein was produced by and purified from recombinant baculoviruses and examined in an enzymatic reaction in vitro, which determined that EBV BALF3 acts as an endonuclease and its activity is modulated by Mg(2+), Mn(2+), and ATP. Moreover, in EBV-positive epithelial cells, BALF3 was expressed and transported from the cytoplasm into the nucleus following induction of the lytic cycle, and gene silencing of BALF3 caused a reduction of DNA packaging and virion release. Interestingly, suppression of BALF3 expression also decreased the efficiency of DNA synthesis. On the basis of these results, we suggest that EBV BALF3 is involved simultaneously in DNA synthesis and packaging and is required for the production of mature virions.
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Heat shock protein complex vaccination induces protection against Helicobacter pylori without exogenous adjuvant.
Vaccine
PUBLISHED: 01-24-2014
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The development of a vaccine against the human gastric pathogen Helicobacter pylori, the main causative agent of gastric adenocarcinoma, has been hampered by a number of issues, including the lack of a mucosal adjuvant for use in humans. Heat shock proteins (Hsp), highly conserved molecules expressed by both bacteria and mammalian species, possess a range of functions, including acting as chaperones for cellular proteins and the ability to activate innate immune receptors. Hsp complex (HspC) vaccines, containing Hsp derived from pathogenic bacteria, are immunostimulatory without addition of an exogenous adjuvant and can induce immunity against their chaperoned proteins. In this study we explored in mice the potential utility of a H. pylori HspC vaccine.
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Preliminary investigation on prevalence of osteoporosis and osteopenia: Should we tune our focus on healthy adults?
Jpn J Nurs Sci
PUBLISHED: 01-16-2014
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Osteoporosis and osteopenia are global health problems with increasing trend, particularly in developed regions. Apart from traditional well-recognized high-risk groups (i.e. postmenopausal women and elders), prevalence of such problems among adults should not be ignored because of the advantages of early detection and health promotion. Therefore, this preliminary study aims to investigate the prevalence of osteoporosis and osteopenia among adult office workers, which represented a relatively large proportion of the population in urbanized cities.
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Comprehensive care improves physical recovery of hip-fractured elderly Taiwanese patients with poor nutritional status.
J Am Med Dir Assoc
PUBLISHED: 01-14-2014
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The effects of nutritional management among other intervention components have not been examined for hip-fractured elderly persons with poor nutritional status. Accordingly, this study explored the intervention effects of an in-home program using a comprehensive care model that included a nutrition-management component on recovery of hip-fractured older persons with poor nutritional status at hospital discharge.
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Distinct Epidermal Keratinocytes Respond to Extremely Low-Frequency Electromagnetic Fields Differently.
PLoS ONE
PUBLISHED: 01-01-2014
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Following an increase in the use of electric appliances that can generate 50 or 60 Hz electromagnetic fields, concerns have intensified regarding the biological effects of extremely low-frequency electromagnetic fields (ELF-EMFs) on human health. Previous epidemiological studies have suggested the carcinogenic potential of environmental exposure to ELF-EMFs, specifically at 50 or 60 Hz. However, the biological mechanism facilitating the effects of ELF-EMFs remains unclear. Cellular studies have yielded inconsistent results regarding the biological effects of ELF-EMFs. The inconsistent results might have been due to diverse cell types. In our previous study, we indicated that 1.5 mT, 60 Hz ELF-EMFs will cause G1 arrest through the activation of the ATM-Chk2-p21 pathway in human keratinocyte HaCaT cells. The aim of the current study was to investigate whether ELF-EMFs cause similar effects in a distinct epidermal keratinocyte, primary normal human epidermal keratinocytes (NHEK), by using the same ELF-EMF exposure system and experimental design. We observed that ELF-EMFs exerted no effects on cell growth, cell proliferation, cell cycle distribution, and the activation of ATM signaling pathway in NHEK cells. We demonstrated that the 2 epidermal keratinocytes responded to ELF-EMFs differently. To further validate this finding, we simultaneously exposed the NHEK and HaCaT cells to ELF-EMFs in the same incubator for 168 h and observed the cell growths. The simultaneous exposure of the two cell types results showed that the NHEK and HaCaT cells exhibited distinct responses to ELF-EMFs. Thus, we confirmed that the biological effects of ELF-EMFs in epidermal keratinocytes are cell type specific. Our findings may partially explain the inconsistent results of previous studies when comparing results across various experimental models.
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Frequency and Fitness Consequences of Bacteriophage ?6 Host Range Mutations.
PLoS ONE
PUBLISHED: 01-01-2014
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Viruses readily mutate and gain the ability to infect novel hosts, but few data are available regarding the number of possible host range-expanding mutations allowing infection of any given novel host, and the fitness consequences of these mutations on original and novel hosts. To gain insight into the process of host range expansion, we isolated and sequenced 69 independent mutants of the dsRNA bacteriophage ?6 able to infect the novel host, Pseudomonas pseudoalcaligenes. In total, we found at least 17 unique suites of mutations among these 69 mutants. We assayed fitness for 13 of 17 mutant genotypes on P. pseudoalcaligenes and the standard laboratory host, P. phaseolicola. Mutants exhibited significantly lower fitnesses on P. pseudoalcaligenes compared to P. phaseolicola. Furthermore, 12 of the 13 assayed mutants showed reduced fitness on P. phaseolicola compared to wildtype ?6, confirming the prevalence of antagonistic pleiotropy during host range expansion. Further experiments revealed that the mechanistic basis of these fitness differences was likely variation in host attachment ability. In addition, using computational protein modeling, we show that host-range expanding mutations occurred in hotspots on the surface of the phage's host attachment protein opposite a putative hydrophobic anchoring domain.
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Validity and clinical utilization of the Chinese version of the Gotland Male Depression Scale at a men's health polyclinic.
Neuropsychiatr Dis Treat
PUBLISHED: 01-01-2014
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Symptoms of depression in males, such as aggression and irritability, are different from those in females. However, there are no adequate scales for detecting possible diagnoses in the Chinese population. The aim of this study was to assess whether the Chinese version of the Gotland Male Depression Scale (CV-GMDS) could identify male depression as effectively as the English version.
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Abbott RealTime HBV assay is more sensitive in detection of low viral load and little impacted by drug resistant mutation in chronic hepatitis B patients under nucleot(s)ide analogues therapy.
PLoS ONE
PUBLISHED: 01-01-2014
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Selection of drug-resistant strains may lead to failure of HBV antiviral therapy. There is little information whether there is detection difference in drug resistant mutations between different viral load assays of HBV.
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The role of the mecA gene in oxacillin resistance in a pvl-positive:ST59 genetic background of a Staphylococcus aureus clinical strain.
Antimicrob. Agents Chemother.
PUBLISHED: 11-25-2013
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The most prevalent community-associated methicillin-resistant Staphylococcus aureus (C-MRSA) strains in Taiwan, ST59 clones, carry staphylococcal cassette chromosome mec (SCCmec) type V and, to a lesser extent, type IV. These strains show wide variation in sensitivity to oxacillin, but the reasons for this variation are unknown. Here we compared the sequence of the mecA gene from different SCCmec type clinical strains and found they contain different mecA promoter mutations. Analysis of mecA promoter activity by reporter-gene fusions showed that single base substitutions in the promoter have a strong influence on mecA transcription. The different mecA variants including promoter sequences were expressed in the methicillin-sensitive Staphylococcus aureus (MSSA) strain C195 (ST59 background). PBP2a production among the parental and promoter mutant mecA genes showed a close correlation with mecA transcription levels. Furthermore, the quantity of PBP2a also closely correlated with the level of oxacillin resistance in the C195 background. Our data suggest that mecA promoter mutations play an important role in determining the level of oxacillin resistance. The mecA promoter mutation G-25A (25 bases upstream of the mecA translation start site) was found to be associated with high oxacillin minimum inhibitory concentration (MIC) (256 ?g/ml), G-7T conferred a moderate oxacillin MIC (32-64 ?g/ml), C-33T showed a low oxacillin MIC (4-8 ?g/ml), and A-38G reversed the effect of the C-33T mutation, restoring the oxacillin resistance level in the double mutant A-38G/C-33T. These observations may explain why C-MRSA strains in Taiwan carrying SCCmec type IV or V have such enormous variation in oxacillin MIC.
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Differential roles of the protein corona in the cellular uptake of nanoporous polymer particles by monocyte and macrophage cell lines.
ACS Nano
PUBLISHED: 11-20-2013
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Many biomolecules, mainly proteins, adsorb onto polymer particles to form a dynamic protein corona in biological environments. The protein corona can significantly influence particle-cell interactions, including internalization and pathway activation. In this work, we demonstrate the differential roles of a given protein corona formed in cell culture media in particle uptake by monocytes and macrophages. By exposing disulfide-stabilized poly(methacrylic acid) nanoporous polymer particles (PMASH NPPs) to complete cell growth media containing 10% fetal bovine serum, a protein corona, with the most abundant component being bovine serum albumin, was characterized. Upon adsorption onto the PMASH NPPs, native bovine serum albumin (BSA) was found to undergo conformational changes. The denatured BSA led to a significant decrease in internalization efficiency in human monocytic cells, THP-1, compared with the bare particles, due to reduced cell membrane adhesion. In contrast, the unfolded BSA on the NPPs triggered class A scavenger receptor-mediated phagocytosis in differentiated macrophage-like cells (dTHP-1) without a significant impact on the overall internalization efficiency. Taken together, this work demonstrates the disparate effects of a given protein corona on particle-cell interactions, highlighting the correlation between protein corona conformation in situ and relevant biological characteristics for biological functionalities.
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Divergent pathways to influence: Cognition and behavior differentially mediate the effects of optimism on physical and mental quality of life in Chinese university students.
J Health Psychol
PUBLISHED: 10-30-2013
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Previous research has indicated that both cognitive and behavioral variables mediate the positive effect of optimism on quality of life; yet few attempts have been made to accommodate these constructs into a single explanatory framework. Adopting Fredricksons broaden-and-build perspective, we examined the relationships between optimism, self-rated health, resilience, exercise, and quality of life in 365 Chinese university students using path analysis. For physical quality of life, a two-stage model, in which the effects of optimism were sequentially mediated by cognitive and behavioral variables, provided the best fit. A one-stage model, with full mediation by cognitive variables, provided the best fit for mental quality of life. This suggests that optimism influences physical and mental quality of life via different pathways.
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The effectiveness of light/dark exposure to treat insomnia in female nurses undertaking shift work during the evening/night shift.
J Clin Sleep Med
PUBLISHED: 07-16-2013
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The present study investigated whether bright light exposure during the first half of the evening/night shift combined with light attenuation in the morning is effective in improving sleep problems in nurses undertaking rotating shift work who suffer from clinical insomnia.
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Comparative proteomics evaluation of plasma exosome isolation techniques and assessment of the stability of exosomes in normal human blood plasma.
Proteomics
PUBLISHED: 07-10-2013
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Exosomes are nanovesicles released by a variety of cells and are detected in body fluids including blood. Recent studies have highlighted the critical application of exosomes as personalized targeted drug delivery vehicles and as reservoirs of disease biomarkers. While these research applications have created significant interest and can be translated into practice, the stability of exosomes needs to be assessed and exosome isolation protocols from blood plasma need to be optimized. To optimize methods to isolate exosomes from blood plasma, we performed a comparative evaluation of three exosome isolation techniques (differential centrifugation coupled with ultracentrifugation, epithelial cell adhesion molecule immunoaffinity pull-down, and OptiPrep(TM) density gradient separation) using normal human plasma. Based on MS, Western blotting and microscopy results, we found that the OptiPrep(TM) density gradient method was superior in isolating pure exosomal populations, devoid of highly abundant plasma proteins. In addition, we assessed the stability of exosomes in plasma over 90 days under various storage conditions. Western blotting analysis using the exosomal marker, TSG101, revealed that exosomes are stable for 90 days. Interestingly, in the context of cellular uptake, the isolated exosomes were able to fuse with target cells revealing that they were indeed biologically active.
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The "Aging Males Symptoms" (AMS) Scale assesses depression and anxiety.
Aging Male
PUBLISHED: 07-04-2013
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Emotional distress may be associated with severe aging symptoms. This study aimed to investigate aging symptoms in male psychiatric outpatients and their relationship with anxiety and depression.
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Adiponectin receptor 1 enhances fatty acid metabolism and cell survival in palmitate-treated HepG2 cells through the PI3 K/AKT pathway.
Eur J Nutr
PUBLISHED: 06-20-2013
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Hepatic lipid overloading induces lipotoxicity which can cause hepatocyte damage, fibrosis, and eventually progress to cirrhosis, which is associated with nonalcoholic fatty liver disease. Adiponectin receptors play important roles in regulating lipid metabolism. In this study, we used a lentivirus system to overexpress the adiponectin receptor 1 (AdipoR1) in HepG2 cells to define the role of adiponectin and its receptor 1 in the development of fatty liver syndrome.
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Comparison of predictive performance of various fatty acids for the risk of cardiovascular disease events and all-cause deaths in a community-based cohort.
Atherosclerosis
PUBLISHED: 06-19-2013
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The issue of whether saturated fats and trans fats are superior predictors of all-cause death and cardiovascular disease than n-3 polyunsaturated fatty acids, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), remains a matter of contention. Furthermore, few studies have examined the relationship between fatty acids and the outcomes of cardiovascular disease (CVD) in Asian populations. The aim of this study was to compare the effectiveness of various plasma fatty acids as predictors for all-cause death and CVD events in an ethnic Chinese population.
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Autocrine CCL3 and CCL4 induced by the oncoprotein LMP1 promote Epstein-Barr virus-triggered B cell proliferation.
J. Virol.
PUBLISHED: 06-12-2013
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Epstein-Barr virus (EBV) alters the regulation and expression of a variety of cytokines in its host cells to modulate host immune surveillance and facilitate viral persistence. Using cytokine antibody arrays, we found that, in addition to the cytokines reported previously, two chemotactic cytokines, CCL3 and CCL4, were induced in EBV-infected B cells and were expressed at high levels in all EBV-immortalized lymphoblastoid cell lines (LCLs). Furthermore, EBV latent membrane protein 1 (LMP1)-mediated Jun N-terminal protein kinase activation was responsible for upregulation of CCL3 and CCL4. Inhibition of CCL3 and CCL4 in LCLs using a short hairpin RNA approach or by neutralizing antibodies suppressed cell proliferation and caused apoptosis, indicating that autocrine CCL3 and CCL4 are required for LCL survival and growth. Importantly, significant amounts of CCL3 were detected in EBV-positive plasma from immunocompromised patients, suggesting that EBV modulates this chemokine in vivo. This study reveals the regulatory mechanism and a novel function of CCL3 and CCL4 in EBV-infected B cells. CCL3 might be useful as a therapeutic target in EBV-associated lymphoproliferative diseases and malignancies.
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A dimensional approach to the phantom vibration and ringing syndrome during medical internship.
J Psychiatr Res
PUBLISHED: 05-19-2013
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Phantom vibrations and ringing of mobile phones are prevalent hallucinations in the general population. They might be considered as a "normal" brain mechanism. The aim of this study was to determine if a dimensional approach to identify individuals suffering from these hallucinations was more important than a categorical approach. A prospective longitudinal study of 74 medical interns (male: 46, mean age: 24.8 ± 1.2) was carried out using repeated investigations of the severity of phantom vibrations and ringing, as well as accompanying symptoms of anxiety and depression as measured by Beck Anxiety Inventory (BAI) and the Beck Depression Inventory (BDI) before, at the 3rd, 6th, and 12th month during internship, and 2 weeks after internship. We utilized the cognitive and somatic subscales of the BDI, as well as the subjective, somatic and panic subscales of the BAI. The correlation between phantom vibration and ringing was lowest before the internship but became moderate during the internship and high 2 weeks after it. Compared to interns with subclinical phantom ringing and vibrations, interns with severe phantom vibrations and ringing had higher subjective and somatic anxiety and somatic depressive scores at any time point throughout the internship. Only interns with severe phantom ringing had more cognitive/affective depression. A dimensional approach to the phantom vibration and ringing syndrome is a powerful way to identify their correlation, as well as their association with anxiety and depression.
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Identification of sinensetin metabolites in rat urine by an isotope-labeling method and ultrahigh-performance liquid chromatography-electrospray ionization mass spectrometry.
J. Agric. Food Chem.
PUBLISHED: 05-16-2013
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Sinensetin (SIN), one of the major polymethoxyflavones (PMFs) contained mainly in the citrus peels, has been reported to possess various bioactivities, including antifungal, antimutagenic, anticancer, and anti-inflammatory activities. Although the biotransformation of SIN in fungi and insects has been reported, the information about the metabolism of SIN in mammals is still unclear. In this study, formation of SIN metabolites in rats was investigated. Four isotope-labeled SINs ([4-D3]SIN, [3-D3]SIN, [5-D3]SIN, and [6-D3]SIN) were synthesized and administered to rat. The urine samples were collected and main metabolites were monitored by ultrahigh-performance liquid chromatography-electrospray ionization mass spectrometry. The administered compound and four SIN metabolites were detected in rat urine. These metabolites were identified as 4-hydroxy-5,6,7,3-tetramethoxyflavone, 5-hydroxy-6,7,3,4-tetramethoxyflavone, 6-hydroxy-5,7,3,4-tetramethoxyflavone, and 7-hydroxy-5,6,3,4-tetramethoxyflavone sulfate.
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Psychometric properties of the internet addiction test in chinese adolescents.
J Pediatr Psychol
PUBLISHED: 05-13-2013
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This study examined the psychometric properties of the Youngs Internet Addiction Test (IAT) in 844 Hong Kong Chinese adolescents (37.7% boys) with mean age of 15.9 (standard deviation = 3.5) years.
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Clear-cell variant of calcifying epithelial odontogenic tumor (Pindborg tumor) in the mandible.
Int J Oral Sci
PUBLISHED: 04-22-2013
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We present an uncommon case (female patient aged 59 years) of the clear-cell variant of calcifying epithelial odontogenic tumor (CEOT) (also known as Pindborg tumor) in the mandible. The clinical characteristics and probable origins of the clear tumor cells of previously reported cases of clear-cell variant of intraosseous CEOT are also summarized and discussed.
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Application of the solvent extraction technique to investigation of the anti-inflammatory activity of adlay bran.
Food Chem
PUBLISHED: 04-11-2013
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The current study utilised a bioassay-directed chemical analysis scheme to screen the anti-inflammatory activity of fractions and compounds from adlay bran (AB). Liquid-liquid extraction couple with liquid chromatography-mass spectrometry (LC-MS) was applied to the isolation, analysis and identification of active components in AB samples. Ethanol extracts of AB (ABE) and ethyl acetate extracts AB (ABEa) were obtained and further partitioned with different solvents. The results showed that among all 16 kinds of fractions from ABE and ABEa, ABEa-Ea-B (80% Ea/n-hexane sub-fraction from ABE-Ea) had the most potent inhibitory effects on NO production, iNOS and COX-2 expressions, and proinflammatory IL-6 and TNF-? secretion in lipopolysaccharide-activated RAW264.7 cells system. Mechanistic data from luciferase reporter-gene assay revealed that the anti-inflammatory action of ABEa-Ea-B may be associated with inhibition of NF-kB transcriptional activity. Notably, tangeretin, nobiletin, and p-hydroxybenzoic acid were found to be the main active compounds for the anti-inflammatory properties in ABEa-Ea-B.
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A type III effector antagonizes death receptor signalling during bacterial gut infection.
Nature
PUBLISHED: 04-08-2013
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Successful infection by enteric bacterial pathogens depends on the ability of the bacteria to colonize the gut, replicate in host tissues and disseminate to other hosts. Pathogens such as Salmonella, Shigella and enteropathogenic and enterohaemorrhagic (EPEC and EHEC, respectively) Escherichia coli use a type III secretion system (T3SS) to deliver virulence effector proteins into host cells during infection that promote colonization and interfere with antimicrobial host responses. Here we report that the T3SS effector NleB1 from EPEC binds to host cell death-domain-containing proteins and thereby inhibits death receptor signalling. Protein interaction studies identified FADD, TRADD and RIPK1 as binding partners of NleB1. NleB1 expressed ectopically or injected by the bacterial T3SS prevented Fas ligand or TNF-induced formation of the canonical death-inducing signalling complex (DISC) and proteolytic activation of caspase-8, an essential step in death-receptor-induced apoptosis. This inhibition depended on the N-acetylglucosamine transferase activity of NleB1, which specifically modified Arg?117 in the death domain of FADD. The importance of the death receptor apoptotic pathway to host defence was demonstrated using mice deficient in the FAS signalling pathway, which showed delayed clearance of the EPEC-like mouse pathogen Citrobacter rodentium and reversion to virulence of an nleB mutant. The activity of NleB suggests that EPEC and other attaching and effacing pathogens antagonize death-receptor-induced apoptosis of infected cells, thereby blocking a major antimicrobial host response.
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Continuous intra-arterial chemotherapy for downstaging locally advanced oral commissure carcinoma.
Head Neck
PUBLISHED: 03-22-2013
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The purpose of this study was to assess the usefulness, safety, and efficacy of intra-arterial (IA) infusion chemotherapy for patients with locally advanced oral commissure cancer.
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Eicosapentaenoic acid attenuated oxidative stress-induced cardiomyoblast apoptosis by activating adaptive autophagy.
Eur J Nutr
PUBLISHED: 02-18-2013
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Recently, several large, randomized clinical trials have proven the benefits of eicosapentaenoic acid (EPA) in cardiovascular prevention. However, the precise protective mechanisms of EPA for heart disease are still controversial. In this study, we evaluate the possible protective effects of EPA, especially the role of autophagy, against cardiomyocyte apoptosis induced by oxidative stress.
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Validity of self-estimated adiposity assessment against general and central adiposity in Hong Kong adolescents.
Ann. Hum. Biol.
PUBLISHED: 02-13-2013
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The relationships between self-estimated adiposity using Stunkards body silhouette scale with general and central adiposity in adolescents are unclear. This study examines the criterion validity of Stunkards body silhouette scale as a self-estimated rating of adiposity against anthropometric measures of adiposity and percentage body fat in Hong Kong adolescents.
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A novel synthetic microtubule inhibitor, MPT0B214 exhibits antitumor activity in human tumor cells through mitochondria-dependent intrinsic pathway.
PLoS ONE
PUBLISHED: 02-08-2013
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Agents that interfere with mitotic progression by disturbing microtubule dynamics are commonly used for cancer treatment. Previously, a series of aroylquinolone regioisomers as novel microtubule inhibitors were discovered. One of these new compounds, MPT0B214 inhibited tubulin polymerization through strongly binding to the tubulins colchicine-binding site and had cytotoxic activity in a variety of human tumor cell lines. After treatment with MPT0B214, KB cells were arrested in the G2-M phase before cell death occurred, which were associated with upregulation of cyclin B1, dephosphorylation of Cdc2, phosphorylation of Cdc25C and elevated expression of the mitotic marker MPM-2. Furthermore, the compound induced apoptotic cell death through mitochondria/caspase 9-dependent pathway. Notably, several KB-derived multidrug-resistant cancer cell lines were also sensitive to MPT0B214 treatment. These findings showed that MPT0B214 is a potential compound in the treatment of various malignancies.
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Virological predictors of response to retreatment in hepatitis C genotype 2 infected patients.
PLoS ONE
PUBLISHED: 02-07-2013
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The impact of virological factors and interleukin-28B (IL-28B) genetic variants on retreatment of hepatitis C virus genotype 2 (HCV-2) treatment-experienced patients remains unknown.
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pH-dependent, thermosensitive polymeric nanocarriers for drug delivery to solid tumors.
Biomaterials
PUBLISHED: 02-07-2013
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Polymeric micelles are promising carriers for anti-cancer agents due to their small size, ease of assembly, and versatility for functionalization. A current challenge in the use of polymeric micelles is the sensitive balance that must be achieved between stability during prolonged blood circulation and release of active drug at the tumor site. Stimuli-responsive materials provide a mechanism for triggered drug release in the acidic tumor and intracellular microenvironments. In this work, we synthesized a series of dual pH- and temperature-responsive block copolymers containing a poly(?-caprolactone) (PCL) hydrophobic block with a poly(triethylene glycol) block that were copolymerized with an amino acid-functionalized monomer. The block copolymers formed micellar structures in aqueous solutions. An optimized polymer that was functionalized with 6-aminocaproic acid (ACA) possessed pH-sensitive phase transitions at mildly acidic pH and body temperature. Doxorubicin-loaded micelles formed from these polymers were stable at blood pH (~7.4) and showed increased drug release at acidic pH. In addition, these micelles displayed more potent anti-cancer activity than free doxorubicin when tested in a tumor xenograft model in mice.
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A Taiwanese food frequency questionnaire correlates with plasma docosahexaenoic acid but not with plasma eicosapentaenoic acid levels: questionnaires and plasma biomarkers.
BMC Med Res Methodol
PUBLISHED: 02-05-2013
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Little evidence is available for the validity of dietary fish and polyunsaturated fatty acid intake derived from interviewer-administered questionnaires and plasma docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) concentration.
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Gender differences in cardiac autonomic modulation during medical internship.
Psychophysiology
PUBLISHED: 01-25-2013
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Medical internship is known to be a time of high stress and long working hours, which increases the risk of depression and cardiovascular disease. Gender differences in medical interns cardiovascular risk have not been reported previously. Thirty-eight medical interns (29 males) were repeatedly tested for depressive symptoms using the Hospital Anxiety and Depression Scale and 5-min spectral analysis of heart rate variability (HRV) at 3-month intervals during their internship. Among the male interns, the variance of the heart rate decreased at 6, 9, 12 months, and a reduced high frequency, which suggests reduced cardiac parasympathetic modulation, was found at 9 and 12 months into their internship. Increased depressive symptoms were also identified at 12 months in the male group. No significant differences in depression or any of the HRV indices were identified among the female interns during their internship.
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Comparative assessment of the HAS-BLED score with other published bleeding risk scoring schemes, for intracranial haemorrhage risk in a non-atrial fibrillation population: the Chin-Shan Community Cohort Study.
Int. J. Cardiol.
PUBLISHED: 01-19-2013
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The HAS-BLED score is a validated bleeding risk model for predicting major bleeding events in anticoagulated individuals with atrial fibrillation (AF). It remains uncertain whether the HAS-BLED score could identify non-AF individuals at risk of developing intracranial haemorrhage (ICH), which is the most intractable and devastating major bleeding complication.
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The associations of sociocultural attitudes towards appearance with body dissatisfaction and eating behaviors in Hong Kong adolescents.
Eat Behav
PUBLISHED: 01-14-2013
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Western culture has great influences on body dissatisfaction and related eating behaviors in adolescents. This study aimed to assess the sociocultural influences on eating attitudes and motivations among Hong Kong Chinese adolescents.
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Albusin B, mass-produced by the Saccharomyces cerevisiae suppression system, enhances lipid utilisation and antioxidant capacity in mice.
J. Sci. Food Agric.
PUBLISHED: 01-14-2013
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BACKGROUND: Albusin B (bacteriocin), isolated from Ruminococcus albus 7 and mass-produced by the Saccharomyces cerevisiae expression system, has previously been shown to have a beneficial effect on lipid metabolism in broiler chickens. The present study was focused on the effect of albusin B on lipid metabolism in mice and the potential of albusin B-expressing yeast product (albusin B) as a food supplement. Forty-five BALB/c male mice at 6?weeks of age were each orally administered normal saline (control), yeast (0.125?mg?kg(-1) ) or albusin B (0.125?mg?kg(-1) ) for 14?days and then euthanised. RESULTS: Compared with the control group, albusin B-fed mice exhibited decreased body weight and plasma levels of triglycerides and free fatty acids but increased plasma high-density lipoprotein. Albusin B-fed mice showed higher mRNA expression of fatty acid oxidation in the ileum, heart and liver than control mice. Compared with the control treatment, both yeast and albusin B treatments caused a decrease in mRNA expression of fatty acid synthesis in the heart and liver. Moreover, albusin B suppressed mRNA levels of lipogenesis in the ileum and liver. Albusin B-fed mice exhibited more favourable adenosine triphosphate production and antioxidant capacity in the heart and liver. Albusin B treatment led to a significantly lower respiratory quotient than that of the control, whereas yeast treatment did not. CONCLUSION: This study demonstrated a beneficial effect of albusin B on lipid utilisation and anti-atherosclerotic and antioxidant capacities in mice. However, more comprehensive studies are required to elucidate the exact mechanism behind the effect of albusin B. © 2013 Society of Chemical Industry.
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Percentage body fat and anthropometric measures in Hong Kong adolescents.
Res Sports Med
PUBLISHED: 01-05-2013
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This study investigates the associations between percentage body fat (%BF) and anthropometric parameters in adolescents of mixed weight status. Anthropometric parameters including height, weight, and waist circumference (WC), and %BF were assessed in 903 Hong Kong Chinese students (mean age 14.7 years). The calculated body mass index (BMI) and waist-to-stature ratio (WSR) were used to classify students into different weight status groups and central obesity groups, respectively. The %BF/BMI and %BF/WC relationships were examined by partial correlation coefficients and linear regression models. The %BF correlated significantly with BMI, except in underweight boys. BMI predicted %BF better (adjusted R (2): 0.40 in boys; 0.85 in girls) than WC (adjusted R (2): 0.34 in boys; 0.63 in girls) or WSR (adjusted R (2): 0.33 in boys; 0.60 in girls). In general, BMI predicts %BF better than WC or WSR in Hong Kong adolescents, but these relationships are sex and weight status specific.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.