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Find video protocols related to scientific articles indexed in Pubmed.
Influence of surface cracks on laser-induced damage resistance of brittle KH2PO4 crystal.
Opt Express
PUBLISHED: 11-18-2014
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Single point diamond turning (SPDT) currently is the leading finishing method for achieving ultra-smooth surface on brittle KH2PO4 crystal. In this work, the light intensification modulated by surface cracks introduced by SPDT cutting is numerically simulated using finite-difference time-domain algorithm. The results indicate that the light intensification caused by surface cracks is wavelength, crack geometry and position dependent. Under the irradiation of 355nm laser, lateral cracks on front surfaces and conical cracks on both front and rear surfaces can produce light intensification as high as hundreds of times, which is sufficient to trigger avalanche ionization and finally lower the laser damage resistance of crystal components. Furthermore, we experimentally tested the laser-induced damage thresholds (LIDTs) on both crack-free and flawed crystal surfaces. The results imply that brittle fracture with a series of surface cracks is the dominant source of laser damage initiation in crystal components. Due to the negative effect of surface cracks, the LIDT on KDP crystal surface could be sharply reduced from 7.85J/cm2 to 2.33J/cm2 (355nm, 6.4ns). In addition, the experiment of laser-induced damage growth is performed and the damage growth behavior agrees well with the simulation results of light intensification caused by surface cracks with increasing crack depths.
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[To accelerate pace of studying standard pieces of Chinese medicine as standard material].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 10-04-2014
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To elucidate the necessary and research of accelerating basic research of Chinese standard pieces as standard materials.
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Characterizing brain mineral deposition in patients with Wilson disease using susceptibility-weighted imaging.
Neurol India
PUBLISHED: 09-20-2014
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The aim of this study was to evaluate the feasibility of characterizing the brain-mineral deposition in patients with Wilson disease (WD) using susceptibility-weighted imaging (SWI).
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Calcineurin upregulates local Ca2+ signaling through ryanodine receptor-1 in airway smooth muscle cells.
Am. J. Physiol. Lung Cell Mol. Physiol.
PUBLISHED: 09-19-2014
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Local Ca(2+) signals (Ca(2+) sparks) play an important role in multiple cellular functions in airway smooth muscle cells (ASMCs). Protein kinase C? is known to downregulate ASMC Ca(2+) sparks and contraction; however, no complementary phosphatase has been shown to produce opposite effects. Here, we for the first time report that treatment with a specific calcineurin (CaN) autoinhibitory peptide (CAIP) to block CaN activity decreases, whereas application of nickel to activate CaN increases, Ca(2+) sparks in both the presence and absence of extracellular Ca(2+). Treatment with xestospogin-C to eliminate functional inositol 1,4,5-trisphosphate receptors does not prevent CAIP from inhibiting local Ca(2+) signaling. However, high ryanodine treatment almost completely blocks spark formation and prevents the nickel-mediated increase in sparks. Unlike CAIP, the protein phosphatase 2A inhibitor endothall has no effect. Local Ca(2+) signaling is lower in CaN catalytic subunit A? gene knockout (CaN-A?(-/-)) mouse ASMCs. The effects of CAIP and nickel are completely lost in CaN-A?(-/-) ASMCs. Neither CAIP nor nickel produces an effect on Ca(2+) sparks in type 1 ryanodine receptor heterozygous knockout (RyR1(-/+)) mouse ASMCs. However, their effects are not altered in RyR2(-/+) or RyR3(-/-) mouse ASMCs. CaN inhibition decreases methacholine-induced contraction in isolated RyR1(+/+) but not RyR1(-/+) mouse tracheal rings. Supportively, muscarinic contractile responses are also reduced in CaN-A?(-/+) mouse tracheal rings. Taken together, these results provide novel evidence that CaN regulates ASMC Ca(2+) sparks specifically through RyR1, which plays an important role in the control of Ca(2+) signaling and contraction in ASMCs.
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Universal predictability of mobility patterns in cities.
J R Soc Interface
PUBLISHED: 09-19-2014
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Despite the long history of modelling human mobility, we continue to lack a highly accurate approach with low data requirements for predicting mobility patterns in cities. Here, we present a population-weighted opportunities model without any adjustable parameters to capture the underlying driving force accounting for human mobility patterns at the city scale. We use various mobility data collected from a number of cities with different characteristics to demonstrate the predictive power of our model. We find that insofar as the spatial distribution of population is available, our model offers universal prediction of mobility patterns in good agreement with real observations, including distance distribution, destination travel constraints and flux. By contrast, the models that succeed in modelling mobility patterns in countries are not applicable in cities, which suggests that there is a diversity of human mobility at different spatial scales. Our model has potential applications in many fields relevant to mobility behaviour in cities, without relying on previous mobility measurements.
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Targeting VEGF/VEGFR in the treatment of psoriasis.
Discov Med
PUBLISHED: 09-18-2014
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Psoriasis is a common chronic skin disorder characterized by cutaneous inflammation and keratinocyte hyperproliferation. In the past decade, a number of novel effective biological agents have been developed to treat moderate-to-severe psoriasis. However, these drugs have potential serious side effects, particularly the development of infectious diseases. Therefore there is still a need for new therapies with better efficacy and less adverse effects. Angiogenesis is implicated in various pathological conditions including psoriasis. Direct targeting of angiogenesis becomes a new therapeutic strategy for the treatment of psoriasis. Vascular endothelial growth factor (VEGF), the most critical angiogenic factor, is thought to play important roles during the pathogenesis of psoriasis and may be a promising target for treating psoriasis. Therefore, we proposed that targeting VEGF/VEGFRs could lead to new treatments for psoriasis.
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X-linked inhibitor of apoptosis-associated factor l (XAFl) enhances the sensitivity of colorectal cancer cells to cisplatin.
Med. Oncol.
PUBLISHED: 09-12-2014
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The purpose of present study was to investigate the roles of X-linked inhibitor of apoptosis-associated factor l (XAFl) in regulation apoptosis of colorectal cancer (CRC) cells after treatment with cisplatin (DDP). A total of ten paired cancerous and non-cancerous tissues were collected from patients with CRC after surgery. The levels of XAFl protein were detected by Western blot. Primary CRC cells were separated from cancer tissues, and its viability or apoptosis after treatment with DDP was determined with MTT or Annexin V/PI assays, respectively. Furthermore, we either up-regulated transfecting a XAF1 overexpression vector or down-regulated XAF1 by siRNA interference. And then, the XAF1 levels and its sensitivity to cisplatin were assessed. XAFl had a lower expression in the cancerous tissues from samples T1, T2 and T3 than their paired non-cancerous tissues N1, N2 and N3. However, the expression of XAF1 was not detected in samples T4 and N1. XAF1 levels in cancer tissues significantly decreased in comparison with normal tissues. Cell abilities of primary cells were significantly decreased in a dose-dependent manner, after treatment with a series concentrations of cisplatin (2, 5, 10 ?g/mL) for 48 h. Although, after down-expression of XAFl by siRNA, cisplatin caused a significant decreases in apoptosis rates in CRC cells. The up-regulation of XAF1 distinctly increased apoptosis in CRC cells administered by cisplatin (P < 0.001). The XAFl could promoted apoptosis and enhanced chemotherapy sensitivity to cisplatin in CRC cells.
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[Influences of three surgical approaches to urethral stricture on the erectile function of the patients].
Zhonghua Nan Ke Xue
PUBLISHED: 09-09-2014
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To evaluate the impacts of three different surgical approaches to urethral stricture on the erectile function of the patients.
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Bacterial Community Structure of Autotrophic Denitrification Biocathode by 454 Pyrosequencing of the 16S rRNA Gene.
Microb. Ecol.
PUBLISHED: 09-01-2014
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Few studies have been conducted to explore the community composition in denitrifying biocathode. Herein, the microbial communities of denitrifying biocathodes yielding current of 1 mA (reactor C1) and 1.5 mA (reactor C2) were characterized by 454 pyrosequencing. The nitrate removal efficiencies in C1 and C2 were about 93 and 85 %, respectively. The optimization of data generated high-quality sequences of 18509 in C1 and 14857 in C2. Proteobacteria was the predominant phylum, and Bacteroidetes, Chloroflexi, and Planctomycetes were the subdominant groups. Classes of Alphaproteobacteria, Anaerolineae, and Phycisphaerae may benefit the performance of current production and nitrate removal. Twenty-nine dominant operational taxonomic units (OTUs) accounted for 64 and 65 % of sequences in C1 and C2, respectively. A denitrifying pathway was constructed based on the phylogenetic analysis and function inferring of the dominant OTUs. Obviously, the 454 pyrosequencing provided a high-resolution profile of bacteria community in denitrifying biocathode.
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[Effect of the potential on bacterial community under illumination by DGGE and T-RFLP].
Huan Jing Ke Xue
PUBLISHED: 08-28-2014
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Potential and illumination regulate the acclimation and growth of exoelectrogenic photosynthetic bacteria in bioelectrochemical systems. To understand the influence of potential on the bacteria community diversity under illumination, PCR-based molecular ecological techniques including denaturing gradient gel electrophoresis (DGGE) and terminal restriction fragment length polymorphism (T-RFLP) were applied to evaluate the bacteria community diversity of biofilm on working electrode. Four potentials of 0, 0.2, 0.4 and 0.6 V (vs. Ag/AgCl) were applied to the working electrode. The DGGE results showed that the band number of the biofilm at 0.6 V was dramatically lower than those at other potentials. The sequencing analysis of these hands showed that most of them belonged to classes of alpha-Proteobacteria, beta-Proteobacteria and Clostridia. The T-RFLP results showed that the number of T-RFs was the largest at 0.2 V and then decreased with increasing potentials. Although the application of DGGE or T-RFLP resulted in different bacterial diversities, both techniques revealed that potential dramatically affected the bacterial diversity and high potential decreased the diversity.
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Macrophage-secreted IL-8 induces epithelial-mesenchymal transition in hepatocellular carcinoma cells by activating the JAK2/STAT3/Snail pathway.
Int. J. Oncol.
PUBLISHED: 08-21-2014
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Macrophages are a major component of the leukocyte infiltrate of tumors and play a pivotal role in the progression of hepatocellular carcinoma (HCC). However, the molecular mechanisms by which macrophages promote HCC invasion are poorly understood. The present study was undertaken to investigate the relationship between macrophages and epithelial-mesenchymal transition (EMT) of HCC. Double-staining immunohistochemistry was used to observe the association between macrophages and EMT markers in clinical HCC samples and it showed that EMT primarily occurred at the edge of the tumor nest, in which infiltrating macrophages were always observed. This indicated that CD68 which is a marker of macrophages, was correlated with EMT marker levels. In addition, after being cultured with macrophages for 24 h, the ability of HCC cells to migrate and invade increased, Snail and N-Cadherin expression was upregulated, and E-Cadherin was downregulated. An antibody array assay was applied to analyze the supernatant of these cultures and it demonstrated IL-8 increased significantly in the macrophage co-culture system. Finally, the role of macrophage-derived IL-8 in the invasion of HCC cells was assayed, and downstream signaling pathways were also investigated. We found that IL-8: i) may induce EMT and promote HCC cell migration and invasion and ii) is associated with the JAK2/STAT3/Snail signaling pathway. Taking together, these findings revealed that macrophages that have infiltrated tumors may induce epithelial-mesenchymal transition of HCC cells via the IL-8 activated JAK2/STAT3/Snail pathway. Thus, this may offer a potential target for developing new HCC therapies.
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Dose of incorporated immunodominant antigen in recombinant BCG impacts modestly on Th1 immune response and protective efficiency against Mycobacterium tuberculosis in mice.
J Immunol Res
PUBLISHED: 07-23-2014
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One approach for improving BCG efficacy is to utilize BCG as vehicle to develop recombinant BCG (rBCG) strains overexpressing Mycobacterium tuberculosis (M. tb) antigens. Also expression level of a candidate antigen should impact the final T cell responses conferred by rBCG. In this study, based on our previously constructed differential expression system, we developed two rBCG strains overexpressing M. tb chimeric antigen Ag856A2 (coding a recombinant ag85a with 2 copies of esat-6 inserted at Acc I site of ag85a) at differential levels under the control of the subtly modified furA promoters. These two rBCG strains were used to vaccinate C57BL/6 mice and exploit dose of incorporated antigen in rBCG to optimize immune response and protective efficiency against M. tb challenge in mouse model. The results showed that rBCG strains overexpressing Ag856A2 at differential levels induced different antigen-specific IFN-? production and comparable number of M. tb-specific CD4 T cells expressing IL-2. M. tb challenge experiment showed that rBCG strains afforded enhanced but comparable immune protection characterized by reduced bacillary load, lung pathology, and inflammation. These results suggested that the dose of antigens incorporated in rBCG can impact T cell immune responses but imposed no significantly differential protective efficacies.
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[Screening active components in compound danshen based on PXR-CYP3A4: an experimental study].
Zhongguo Zhong Xi Yi Jie He Za Zhi
PUBLISHED: 06-20-2014
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To screen active components in Compound Danshen (CD) based on pregnane X receptor-cytochrome P450 3A4 (PXR-CYP3A4).
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Establishment of regions of genomic activity during the Drosophila maternal to zygotic transition.
Elife
PUBLISHED: 06-19-2014
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We describe the genome-wide distributions and temporal dynamics of nucleosomes and post-translational histone modifications throughout the maternal-to-zygotic transition in embryos of Drosophila melanogaster. At mitotic cycle 8, when few zygotic genes are being transcribed, embryonic chromatin is in a relatively simple state: there are few nucleosome free regions, undetectable levels of the histone methylation marks characteristic of mature chromatin, and low levels of histone acetylation at a relatively small number of loci. Histone acetylation increases by cycle 12, but it is not until cycle 14 that nucleosome free regions and domains of histone methylation become widespread. Early histone acetylation is strongly associated with regions that we have previously shown to be bound in early embryos by the maternally deposited transcription factor Zelda, suggesting that Zelda triggers a cascade of events, including the accumulation of specific histone modifications, that plays a role in the subsequent activation of these sequences.
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Alkaloids from Xylariaceae sp., a marine-derived fungus.
Nat Prod Commun
PUBLISHED: 05-30-2014
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A new pyridine derivative, 5-(2'-hydroxypropyl)pyridin-3-ol (1), with seven known alkaloids, 3-hydroxy-5-methyl-5,6-dihydro-7H-cyclopenta[b]pyridin-7-one (2), penicillenol A1 (3), penicillenol A2 (4), a mixture of quinolactacin AI (5a) and quinolactacin A2 (5b), and a mixture of quinolactacin C1 (6a) and quinolactacin C2 (6b), were isolated from the culture broth of a marine-derived fungus Xylariaceae sp. SCSGAF0086. Their structures were elucidated by spectroscopic methods. Compound 2 showed weak antimicrobial activity against Bacillus subtilis, and a mixture of 6a and 6b exhibited strong antifouling activity toward Bugula neritina larval settlement.
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[Analysis of leave FTIR of nine kinds of plants from rosaceae with genetic relationship].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 05-15-2014
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Leaves of nine kinds of plants from three subfamily of Rosaceae were used as materials. Genetic relationship was analyzed and species were identified through studying FTIR of nine kinds of plants. Leaves mainly contain large amounts of carbohydrates, proteins, lipids, nucleic acids and other substances. The peaks of carbohydrates are mainly between 1440 and 775 cm(-1). The vibration peaks of the cellulose and lignin are between 1440 and 1337 cm(-1). The peaks between 1000 and 775 cm(-1) are stretching vibration of ribose. The vibration peaks of protein are between 1620 and 1235 cm(-1). The peak at 1620 cm(-1) is sensitive to C=O stretching vibration of protein amide I. The peak at 1523 cm(-1) is assigned to N-H and C-N stretching vibration of protein amide II. Peaks of lipids mainly appeared between 2930 and 1380 cm(-1). The peak at 2922 cm(-1) is CH2 stretching vibration of fat. The peak at 1732 cm(-1) is C=O stretching vibration of fatty acids. The mark peak of the nucleic acid appears in the region between 1250 and 1000 cm(-1). The peak at 1068 cm(-1) is due to the symmetric stretching vibration of PO(2-) group of the phosphodiester-deoxyribose backbone, and the peak at 1246 cm(-1) is associated to the asymmetric stretch vibration of PO(2-) group. The results showed that the cluster model is established by smoothing, standardizing, the second derivative, principal component analysis and Hierarchical cluster analysis. It is accordant with the traditional classification. The result of cluster shows that Prunus armeniaca L. and Prunus seudocerasus Lindl. were clustered into one (Prunoideae). Potentilla fulgens Wall. Rosa chinensis Jacd and Fragaria ananassa Duchesne var. were clustered into the second (Rosoideae). Pyracantha fortuneana Li, Malus pumila Mill. Eriobotrya bengalensis Hook. f. and Malus hallianna Koehne were clustered into the third (Pomoideae). The correct rate of cluster at subfamily is 100%. The correct rate of cluster at genus is 55.56%. The correct rate of identification is 100% when unknown species waiting for determined were laid into the model of Hierarchical cluster to identify. This study provides a new thought and method for genetic relationship analysis of planst.
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Sol-gel-Derived highly sensitive optical oxygen sensing materials using Ru(II) complex via covalent grafting strategy.
J Nanosci Nanotechnol
PUBLISHED: 04-18-2014
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The preparation and oxygen sensing properties of Ru(ll) covalently-grafted and physically-incorporated silica based hybrid materials by sol-gel technique are described in this article. The Ru(II) complexes are successfully grafted onto the backbone of the silica via the condensation reaction of the tetraethoxysilane and the functionalized Ru(II) complex 2-[4'-{3-(Triethoxysilyl)propyl}phenyl]imidazo [4,5-f]-1,10-phenanthroline that contains the hydrolysable tri-alkoxylsilyl group. The luminescence quenching of Ru(II) complex by oxygen within the silica matrix is efficient. The oxygen quenching sensitivity of the covalently-grafted sample is higher than that of the physically-incorporated one due to the strong Si-CH2 bond that is useful to prolong the excited state lifetimes and enhance the photobleaching of the luminophore. The downward oxygen sensing Stern-Volmer plots can be well fitted using the Demas two-site model and the Lehrer model due to the heterogeneous distribution of the Ru(ll) complex within the sol-gel derived silica.
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Dihydrothiophene-condensed chromones from a marine-derived fungus Penicillium oxalicum and their structure-bioactivity relationship.
Bioorg. Med. Chem. Lett.
PUBLISHED: 03-25-2014
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Four dihydrothiophene-condensed chromones including two new compounds oxalicumones D-E (1-2) and known oxalicumones A-B (3-4), along with five other known chromones were isolated from a culture broth of the marine gorgonian-associated fungus Penicillium oxalicum SCSGAF 0023. The structures of 1-2 were elucidated by spectroscopic analysis. Eleven derivatives 3a-3i and 4a-4b were obtained from the acylation of 3 and 4, respectively. Compounds 1-4, 3a-3e, 3g-3h, and 4b showed significant cytotoxicity against several carcinoma cell lines with IC50 ? 10 ?M. And their structure-bioactivity relationship was discussed.
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Simple, green and high-yield production of single- or few-layer graphene by hydrothermal exfoliation of graphite.
Nanoscale
PUBLISHED: 03-18-2014
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Graphene is widely used as promising electronic material and devices, owing to its exceptional electronic and optoelectronic properties. Up to now, defect-free graphene has been limited to the method for controllable, reproducible and scalable mass production. A simple, green, and nontoxic approach for large-scale preparation of high quality graphene is produced by exfoliation of graphite sheets collaborated with intercalant (FeCl2) under hydrothermal conditions, the absence of defects or oxides in graphene with a yield up to 10 wt% can be a practical application and industrial process such as optical limiters, transparent conductors, and sensors. This new process could potentially be improved to give a yield of up to 35 wt% of the starting graphite mass with sediment recycling. We show with experiments and theories that exfoliation graphene is the result of a combined action by diminishing the van der Waals interactions between graphite layers and the shear force drove by the Brownian motion of H2O and FeCl2 molecules. Hydrothermal exfoliation has potential applications in the exfoliation of other layered materials (e.g. BN, MoS2) and carbon nantubes, and in the synthesis of intercalation compounds, nanoribbons, and nanoparticles, thus opening new ways of exfoliation engineering.
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Increased plasma levels of the methylglyoxal in patients with newly diagnosed type 2 diabetes 2.
J Diabetes
PUBLISHED: 03-09-2014
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Methylglyoxal (MG) is a reactive-dicarbonyl that is thought to contribute to the development of diabetes either as a precursor for advanced glycation end products or as a direct toxin. The present study was designed to determine plasma MG level in patients with newly diagnosed type 2 diabetes mellitus (T2DM) and to evaluate the relationship between MG and other parameters, such as oxidative stress and metabolic indices.
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Artemisinin protects against dextran sulfate-sodium-induced inflammatory bowel disease, which is associated with activation of the pregnane X receptor.
Eur. J. Pharmacol.
PUBLISHED: 03-07-2014
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Artemisinin has been used to treat malaria for centuries in the context of traditional Chinese medicine. In the present study, the effects of artemisinin on pregnane X receptor (PXR)-mediated CYP3A expression and its therapeutic role in inflammatory bowel disease were investigated. LS174T cells exposed to artemisinin at various concentrations and for different periods of time were examined with respect to the specific induction of CYP3A4 and PXR mRNA expression. Transient transfection experiments showed transcriptional activation of the CYP3A4 gene through artemisinin to be PXR-dependent. An electrophoretic-mobility shift assay (EMSA) showed that artemisinin activates the DNA-binding capacity of the PXR for the CYP3A4 element. These results indicate that the induction of CYP3A4 by artemisinin is mediated through the activation of PXR. Using animal models, it was demonstrated that artemisinin abrogates dextran sulfate sodium (DDS)-induced intestinal inflammation. Preadministration of artemisinin ameliorated the clinical hallmarks of colitis in DSS-treated mice as determined by body weight loss and assessment of diarrhea, rectal bleeding, colon length, and histology. Artemisinin was found to prevent or reduce the severity of colonic inflammation by inducing CYP3A expression by activation of PXR.
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A derived network-based interferon-related signature of human macrophages responding to Mycobacterium tuberculosis.
Biomed Res Int
PUBLISHED: 02-23-2014
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Network analysis of transcriptional signature typically relies on direct interaction between two highly expressed genes. However, this approach misses indirect and biological relevant interactions through a third factor (hub). Here we determine whether a hub-based network analysis can select an improved signature subset that correlates with a biological change in a stronger manner than the original signature. We have previously reported an interferon-related transcriptional signature (THP1r2Mtb-induced) from Mycobacterium tuberculosis (M. tb)-infected THP-1 human macrophage. We selected hub-connected THP1r2Mtb-induced genes into the refined network signature TMtb-iNet and grouped the excluded genes into the excluded signature TMtb-iEx. TMtb-iNet retained the enrichment of binding sites of interferon-related transcription factors and contained relatively more interferon-related interacting genes when compared to THP1r2Mtb-induced signature. TMtb-iNet correlated as strongly as THP1r2Mtb-induced signature on a public transcriptional dataset of patients with pulmonary tuberculosis (PTB). TMtb-iNet correlated more strongly in CD4(+) and CD8(+) T cells from PTB patients than THP1r2Mtb-induced signature and TMtb-iEx. When TMtb-iNet was applied to data during clinical therapy of tuberculosis, it resulted in the most pronounced response and the weakest correlation. Correlation on dataset from patients with AIDS or malaria was stronger for TMtb-iNet, indicating an involvement of TMtb-iNet in these chronic human infections. Collectively, the significance of this work is twofold: (1) we disseminate a hub-based approach in generating a biologically meaningful and clinically useful signature; (2) using this approach we introduce a new network-based signature and demonstrate its promising applications in understanding host responses to infections.
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shRNA constructs targeting IGFBP-3 alleviate age related erectile dysfunction in the rat.
J. Urol.
PUBLISHED: 02-18-2014
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We investigated whether injecting shRNA constructs targeting IGFBP-3 in the penis of old rats would improve erectile function.
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Comparison of plasmid DNA versus PCR amplified gene of insert DNA for nucleofection in Kasumi-1 cells.
Cytotechnology
PUBLISHED: 01-28-2014
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Plasmid electroporation, or its optimized version nucleofection, is an important technique for gene transfection of cells in suspension. However, substantial cell death and/or low transfection efficiency are still common for some cell lines. By using enhanced green fluorescent protein (EGFP) as a reporter, we compared the use of PCR amplified EGFP (PaEGFP) and its parental plasmid (pEGFP-N2) for nucleofection in Kasumi-1 cells. We found that PaEGFP induced significantly lower cell death but had similar transfection efficiency compared to its parent plasmid (pEGFP-N2). Most importantly, contrary to the pEGFP-N2-nucleofected cells, the PaEGFP-nucleofected cells subsequently grew properly. Tests in other cell lines also implied that PaEGFP indeed induced consistently less cell death, but transfection efficiencies varied, being good in suspension cell lines but lower in adhesive cell lines. We suggest that direct transfection with PCR amplified genes can be a simple and useful approach for optimization of electropulse-based transfection not only of Kasumi-1 cells, but also may be useful for other cell lines that are difficult to transfect in suspension.
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Bitter tastants induce relaxation of rat thoracic aorta precontracted with high K(+).
Clin. Exp. Pharmacol. Physiol.
PUBLISHED: 01-27-2014
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It has been reported that bitter tastants decrease blood pressure and relax precontracted vascular smooth muscle. However, the underlying mechanisms remain unclear. The aim of the present study was to determine the mechanism underlying the vasorelaxant effect of the bitter tastants. Thoracic aortic rings were isolated from Wistar rats and contractions were measured using an isometric myograph. Intracellular Ca(2+) ([Ca(2+)]i) in single rat thoracic aortic smooth muscle cells was recorded by calcium imaging. Calcium currents in single cells were recorded using patch-clamp techniques. High K(+) (140 mmol/L) induced contractions in rat thoracic aortic rings that were inhibited by 3 mmol/L chloroquine, 3 mmol/L denatonium and 10 ?mol/L nifedipine. In single rat thoracic aortic smooth muscle cells, high K(+) increased [Ca(2+)]i and this effect was also blocked by 3 mmol/L chloroquine and 10 ?mol/L nifedipine. Under Ca(2+) -free conditions, high K(+) failed to induce contractions in rat thoracic aortic rings. On its own, chloroquine had no effect on the muscle tension of rat aortic rings and [Ca(2+) ]i. The vasorelaxant effects of chloroquine on precontracted rat thoracic aortic rings were not altered by either 1 ?g/mL pertussis toxin (PTX), an inhibitor of G?o/i-protein, or 1 mmol/L gallein, an inhibitor of G??-protein. The results of patch-clamp analysis in single cells indicate that 1 mmol/L chloroquine blocks voltage-dependent L-type Ca(2+) channel (VDLCC) currents from both extracellular and intracellular sides. Together, the results indicate that chloroquine can block VDLCC, independent of PTX- and gallein-sensitive G-proteins, resulting in relaxation of high K(+)-precontracted thoracic aortic smooth muscle.
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Antifouling potentials of eight deep-sea-derived fungi from the South China Sea.
J. Ind. Microbiol. Biotechnol.
PUBLISHED: 01-24-2014
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Marine-derived microbial secondary metabolites are promising potential sources of nontoxic antifouling agents. The search for environmentally friendly and low-toxic antifouling components guided us to investigate the antifouling potentials of eight novel fungal isolates from deep-sea sediments of the South China Sea. Sixteen crude ethyl acetate extracts of the eight fungal isolates showed distinct antibacterial activity against three marine bacteria (Loktanella hongkongensis UST950701-009, Micrococcus luteus UST950701-006 and Pseudoalteromonas piscida UST010620-005), or significant antilarval activity against larval settlement of bryozoan Bugula neritina. Furthermore, the extract of Aspergillus westerdijkiae DFFSCS013 displayed strong antifouling activity in a field trial lasting 4 months. By further bioassay-guided isolation, five antifouling alkaloids including brevianamide F, circumdatin F and L, notoamide C, and 5-chlorosclerotiamide were isolated from the extract of A. westerdijkiae DFFSCS013. This is the first report about the antifouling potentials of metabolites of the deep-sea-derived fungi from the South China Sea, and the first stage towards the development of non- or low-toxic antifouling agents from deep-sea-derived fungi.
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Analysis of multiple transcriptomes of the African oil palm (Elaeis guineensis) to identify reference genes for RT-qPCR.
J. Biotechnol.
PUBLISHED: 01-14-2014
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The African oil palm (Elaeis guineensis), which is grown in tropical and subtropical regions, is a highly productive oil-bearing crop. For gene expression-based analyses such as reverse transcription-quantitative real time PCR (RT-qPCR), reference genes are essential to provide a baseline with which to quantify relative gene expression. Normalization using reliable reference genes is critical in correctly interpreting expression data from RT-qPCR. In order to identify suitable reference genes in African oil palm, 17 transcriptomes of different tissues obtained from NCBI were systematically assessed for gene expression variation. In total, 53 putative candidate reference genes with coefficient of variation values <3.0 were identified: 18 in reproductive tissue and 35 in vegetative tissue. Analysis for enriched functions showed that approximately 90% of identified genes were clustered in cell component gene functions, and 12 out of 53 genes were traditional housekeeping genes. We selected and validated 16 reference genes chosen from leaf tissue transcriptomes by using RT-qPCR in sets of cold, drought and high salinity treated samples, and ranked expression stability using statistical algorithms geNorm, Normfinder and Bestkeeper. Genes encoding actin, adenine phosphoribosyltransferase and eukaryotic initiation factor 4A genes were the most stable genes over the cold, drought and high salinity stresses. Identification of stably expressed genes as reference gene candidates from multiple transcriptome datasets was found to be reliable and efficient, and some traditional housekeeping genes were more stably expressed than others. We provide a useful molecular genetic resource for future gene expression studies in African oil palm, facilitating molecular genetics approaches for crop improvement in this species.
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Perineal endometriosis: a case report.
Int J Clin Exp Med
PUBLISHED: 01-01-2014
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A previously healthy 28-year-old G1P1 Asian woman presented with a 1-year history of a painful palpable lesion arising within the left perineum. Histopathology revealed multiple endometriotic foci composed of endometrial glands and moderate dense stroma, surrounded by dense fibro-elastic tissue. This patient was diagnosed as endometriosis and the endometriotic mass was excised under local anaesthesia.
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Influence of polyethylene glycol coating on biodistribution and toxicity of nanoscale graphene oxide in mice after intravenous injection.
Int J Nanomedicine
PUBLISHED: 01-01-2014
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In this study, we assessed the in vivo behavior and toxicology of nanoscale graphene oxide (NGO) in mice after intravenous injection. The influence of a polyethylene glycol (PEG) coating on the distribution and toxicity of the NGO was also investigated. The results show that NGO is mainly retained in the liver, lung, and spleen. Retention in the lung is partially due to NGO aggregation. The PEG coating reduces the retention of NGO in the liver, lung, and spleen and promotes the clearance of NGO from these organs, but NGO and NGO-PEG are still present after 3 months. The PEG coating effectively reduces the early weight loss caused by NGO and alleviates NGO-induced acute tissue injuries, which can include damage to the liver, lung, and kidney, and chronic hepatic and lung fibrosis.
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Insights into deep-sea sediment fungal communities from the East Indian ocean using targeted environmental sequencing combined with traditional cultivation.
PLoS ONE
PUBLISHED: 01-01-2014
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The fungal diversity in deep-sea environments has recently gained an increasing amount attention. Our knowledge and understanding of the true fungal diversity and the role it plays in deep-sea environments, however, is still limited. We investigated the fungal community structure in five sediments from a depth of ?4000 m in the East India Ocean using a combination of targeted environmental sequencing and traditional cultivation. This approach resulted in the recovery of a total of 45 fungal operational taxonomic units (OTUs) and 20 culturable fungal phylotypes. This finding indicates that there is a great amount of fungal diversity in the deep-sea sediments collected in the East Indian Ocean. Three fungal OTUs and one culturable phylotype demonstrated high divergence (89%-97%) from the existing sequences in the GenBank. Moreover, 44.4% fungal OTUs and 30% culturable fungal phylotypes are new reports for deep-sea sediments. These results suggest that the deep-sea sediments from the East India Ocean can serve as habitats for new fungal communities compared with other deep-sea environments. In addition, different fungal community could be detected when using targeted environmental sequencing compared with traditional cultivation in this study, which suggests that a combination of targeted environmental sequencing and traditional cultivation will generate a more diverse fungal community in deep-sea environments than using either targeted environmental sequencing or traditional cultivation alone. This study is the first to report new insights into the fungal communities in deep-sea sediments from the East Indian Ocean, which increases our knowledge and understanding of the fungal diversity in deep-sea environments.
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Non-selective cation channels mediate chloroquine-induced relaxation in precontracted mouse airway smooth muscle.
PLoS ONE
PUBLISHED: 01-01-2014
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Bitter tastants can induce relaxation in precontracted airway smooth muscle by activating big-conductance potassium channels (BKs) or by inactivating voltage-dependent L-type Ca2+ channels (VDLCCs). In this study, a new pathway for bitter tastant-induced relaxation was defined and investigated. We found nifedipine-insensitive and bitter tastant chloroquine-sensitive relaxation in epithelium-denuded mouse tracheal rings (TRs) precontracted with acetylcholine (ACH). In the presence of nifedipine (10 µM), ACH induced cytosolic Ca2+ elevation and cell shortening in single airway smooth muscle cells (ASMCs), and these changes were inhibited by chloroquine. In TRs, ACH triggered a transient contraction under Ca2+-free conditions, and, following a restoration of Ca2+, a strong contraction occurred, which was inhibited by chloroquine. Moreover, the ACH-activated whole-cell and single channel currents of non-selective cation channels (NSCCs) were blocked by chloroquine. Pyrazole 3 (Pyr3), an inhibitor of transient receptor potential C3 (TRPC3) channels, partially inhibited ACH-induced contraction, intracellular Ca2+ elevation, and NSCC currents. These results demonstrate that NSCCs play a role in bitter tastant-induced relaxation in precontracted airway smooth muscle.
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Combination of gefitinib and DNA methylation inhibitor decitabine exerts synergistic anti-cancer activity in colon cancer cells.
PLoS ONE
PUBLISHED: 01-01-2014
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Despite recent advances in the treatment of human colon cancer, the chemotherapy efficacy against colon cancer is still unsatisfactory. In the present study, effects of concomitant inhibition of the epidermal growth factor receptor (EGFR) and DNA methyltransferase were examined in human colon cancer cells. We demonstrated that decitabine (a DNA methyltransferase inhibitor) synergized with gefitinib (an EGFR inhibitor) to reduce cell viability and colony formation in SW1116 and LOVO cells. However, the combination of the two compounds displayed minimal toxicity to NCM460 cells, a normal human colon mucosal epithelial cell line. The combination was also more effective at inhibiting the AKT/mTOR/S6 kinase pathway. In addition, the combination of decitabine with gefitinib markedly inhibited colon cancer cell migration. Furthermore, gefitinib synergistically enhanced decitabine-induced cytotoxicity was primarily due to apoptosis as shown by Annexin V labeling that was attenuated by z-VAD-fmk, a pan caspase inhibitor. Concomitantly, cell apoptosis resulting from the co-treatment of gefitinib and decitabine was accompanied by induction of BAX, cleaved caspase 3 and cleaved PARP, along with reduction of Bcl-2 compared to treatment with either drug alone. Interestingly, combined treatment with these two drugs increased the expression of XIAP-associated factor 1 (XAF1) which play an important role in cell apoptosis. Moreover, small interfering RNA (siRNA) depletion of XAF1 significantly attenuated colon cancer cells apoptosis induced by the combination of the two drugs. Our findings suggested that gefitinib in combination with decitabine exerted enhanced cell apoptosis in colon cancer cells were involved in mitochondrial-mediated pathway and induction of XAF1 expression. In conclusion, based on the observations from our study, we suggested that the combined administration of these two drugs might be considered as a novel therapeutic regimen for treating colon cancer.
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Decreased expression of GATA2 promoted proliferation, migration and invasion of HepG2 in vitro and correlated with poor prognosis of hepatocellular carcinoma.
PLoS ONE
PUBLISHED: 01-01-2014
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GATA family of transcription factors are critical for organ development and associated with progression of various cancer types. However, their expression patterns and prognostic values for hepatocellular carcinoma (HCC) are still largely unknown.
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Simple additive-free method to manganese monoxide mesocrystals and their template application for the synthesis of carbon and graphitic hollow octahedrons.
ACS Appl Mater Interfaces
PUBLISHED: 12-02-2013
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Mesocrystals are of great importance owing to their novel hierarchical microstructures and potential applications. In the present work, a simple additive-free method has been developed for the controllable synthesis of manganese monoxide (MnO) mesocrystals, in which cheap manganese acetate (Mn(Ac)2) and ethanol were used as raw materials without involving any other expensive additives such as surfactants, polyelectrolyte, or polymers. The particle size of the resulting MnO mesocrystals is tunable in the range 400-1500 nm by simply altering the concentration of Mn(Ac)2 in ethanol. The percentage yield of the octahedral MnO mesocrystals is about 38 wt % with respect to the starting Mn(Ac)2. The selective adsorption of oligomers, which was resulted from the polymerization of ethanol, acted as an important role for the mesocrystal formation. A mechanism involving the oriented aggregation of MnO nanoparticle subunits and the subsequent ripening process was proposed. Moreover, for the first time, the as-synthesized MnO mesocrystals were employed as a novel template to fabricate functional materials with an octahedral morphology including MnO@C core/shells, carbon, and graphitic hollow octahedrons. This method shows the importance of mesocrystals not only for the field of material research but also for the application in functional materials synthesis.
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Mycobacterial MazG Safeguards Genetic Stability via Housecleaning of 5-OH-dCTP.
PLoS Pathog.
PUBLISHED: 12-01-2013
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Generation of reactive oxygen species and reactive nitrogen species in phagocytes is an important innate immune response mechanism to eliminate microbial pathogens. It is known that deoxynucleotides (dNTPs), the precursor nucleotides to DNA synthesis, are one group of the significant targets for these oxidants and incorporation of oxidized dNTPs into genomic DNA may cause mutations and even cell death. Here we show that the mycobacterial dNTP pyrophosphohydrolase MazG safeguards the bacilli genome by degrading 5-OH-dCTP, thereby, preventing it from incorporation into DNA. Deletion of the (d)NTP pyrophosphohydrolase-encoding mazG in mycobacteria leads to a mutator phenotype both under oxidative stress and in the stationary phase of growth, resulting in increased CG to TA mutations. Biochemical analyses demonstrate that mycobacterial MazG can efficiently hydrolyze 5-OH-dCTP, an oxidized nucleotide that induces CG to TA mutation upon incorporation by polymerase. Moreover, chemical genetic analyses show that direct incorporation of 5-OH-dCTP into mazG-null mutant strain of Mycobacterium smegmatis (Msm) leads to a dose-dependent mutagenesis phenotype, indicating that 5-OH-dCTP is a natural substrate of mycobacterial MazG. Furthermore, deletion of mazG in Mycobacterium tuberculosis (Mtb) leads to reduced survival in activated macrophages and in the spleen of infected mice. This study not only characterizes the mycobacterial MazG as a novel pyrimidine-specific housecleaning enzyme that prevents CG to TA mutation by degrading 5-OH-dCTP but also reveals a genome-safeguarding mechanism for survival of Mtb in vivo.
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CXCL5 contributes to tumour metastasis and recurrence of intrahepatic cholangiocarcinoma by recruiting infiltrative intratumoural neutrophils.
Carcinogenesis
PUBLISHED: 11-30-2013
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CXCL5 is a member of the CXC-type chemokine family that may play a role in carcinogenesis and cancer progression. This study investigates the biological function and clinical significance of CXCL5 in intrahepatic cholangiocarcinoma (ICC). We demonstrated that CXCL5 was overexpressed in ICC cell lines and tumour samples compared with paired normal tissues. CXCL5 had a direct chemoattractant effect on neutrophils in vitro through PI3K-Akt and ERK1/2 signalling pathways. In animal studies, CXCL5 promoted tumour growth and metastasis without altering in vitro proliferative and invasive ability of ICC cells, and this effect was mediated by the recruitment of intratumoural infiltrative neutrophils by tumour-derived CXCL5. Immunohistochemical analysis of ICC samples showed that overexpression of CXCL5 correlated strongly with intratumoural neutrophil infiltration, shorter overall survival, and high tumour recurrence. Multivariate analysis revealed that CXCL5 overexpression alone, or combined with the presence of intratumoural neutrophils, was an independent prognostic indicator for ICC. In conclusion, our data showed that CXCL5 promotes ICC growth and metastasis by recruiting intratumoural neutrophils. CXCL5 alone or combined with intratumoural neutrophils is a novel prognostic predictor for ICC patients and a potential therapeutic target.
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Generalized pure cutaneous Rosai-Dorfman disease: a link between inflammation and cancer not associated with mitochondrial DNA and SLC29A3 gene mutation?
Discov Med
PUBLISHED: 11-16-2013
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Recently, we described a case of generalized pure cutaneous Rosai-Dorfman disease in a 43-year-old Asian man in JAMA. The lesions distributed on nearly all of the skin of the whole body, except for mucous sites. Molecular, immunophenotypic, and sequencing analyses seem to define it as a histiocytic-mesenchymal transition and intermediate proliferative histiocytosis not associated with mtDNA large deletion and pathogenic mutation, as well as the SLC29A3 gene mutation.
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The mechanics of left ventricular filling during the strain phase of the valsalva maneuver in healthy subjects.
Am. J. Med. Sci.
PUBLISHED: 10-26-2013
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The aim of this study was to investigate the mechanical changes in left ventricular filling during the strain phase of the Valsalva maneuver in healthy subjects.
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[Blood pressure lowering efficacy of telmisartan and amlodipine taking on the morning or at bedtime: ABPM results].
Zhonghua Xin Xue Guan Bing Za Zhi
PUBLISHED: 10-12-2013
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To observe the blood lowering effect of telmisartan and amlodipine taking on the morning or at bedtime in hypertensive patients.
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Three new polyketides from marine-derived fungus Penicillium citrinum SCSGAF 0167.
Nat. Prod. Res.
PUBLISHED: 10-04-2013
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Three new polyketides penicitrinol G (1), penicitrinol H (2) and 2,11-dihydroxy-1-methoxycarbonyl-9-carboxylxanthone (3) together with one known cathepsin B inhibitor chrysophanol (4) were isolated from a culture broth of marine-derived fungus Penicillium citrinum SCSGAF 0167. Their structures were determined by spectroscopic methods. Compound 4 exhibited inhibitory activity against cathepsin B with IC50 value of 1.7 ?M.
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A new macrolide from a marine-derived fungus Aspergillus sp.
Nat Prod Commun
PUBLISHED: 10-02-2013
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A new 16-membered macrolide named aspergillide D (1), along with six known compounds, including two polyketones (2-3) and four alkaloids (4-7), were isolated from the culture broth of a marine-derived fungus Aspergillus sp. SCSGAF 0076. The structure of 1 was elucidated on the basis of NMR and mass spectra. Compound 5 showed an obvious inhibitory effect on influenza virus strains H1N1 and H3N2.
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Two new compounds from gorgonian-associated fungus Aspergillus sp.
Nat Prod Commun
PUBLISHED: 10-02-2013
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One new gamma-lactone derivative 5-hydroxy-3-isopropyl-4-methoxyfuranone (1) and one new lactam derivative dehydrated-marinamide (2), along with two known compounds marinamide (3) and marinamide methyl ester (4) were isolated from the fermentation broth of the marine gorgonian-associated fungus Aspergillus sp. SCSGAF0093. Their structures were elucidated on the basis of spectroscopic and spectrometric analysis. Compound 1 showed significant toxicity to brine shrimp (Artemia salina) with a median lethal concentration (LC50) of 1.25 microM, and 3 inhibited protein tyrosine phosphatase 1B (PTP1B) with a half maximal inhibitory concentration (IC50) of 23.3 microg/mL.
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Cardioprotection of Shenfu preparata on cardiac myocytes through cytochrome P450 2J3.
J Integr Med
PUBLISHED: 09-26-2013
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To evaluate whether Shenfu injection (SFI) protects against cardiac myocyte injury induced by Fupian injection (FPI) in vitro.
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Cytotoxic dihydrothiophene-condensed chromones from the marine-derived fungus Penicillium oxalicum.
Planta Med.
PUBLISHED: 09-13-2013
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Two new dihydrothiophene-condensed chromones and a new natural chromone, namely oxalicumones A-C (1-3), respectively, were isolated from a culture broth of a marine-derived fungus, Penicillium oxalicum. The structures of 1-3 and acetylated derivatives of 1 (4-7) were elucidated on the basis of spectroscopic methods and chemical reactions. The absolute configuration of 1 and 2 were established by using the modified Mosher ester method and circular dichroism data of an in situ formed [Rh2(OCOCF3)4] and [Mo2(OAc)4] complex. (R)-MTPA ester of 1 showed cytotoxicity against A375, SW-620, and HeLa carcinoma cell lines with IC50 values of 8.9, 7.8, and 18.4 µM, respectively. Compound 1 displayed cytotoxicity against A375 and SW-620 cell lines with IC50 values of 11.7 and 22.6 µM, respectively. The structure-biological activity relationship of 1 was discussed.
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Fabrication of spherical mitigation pit on KH2PO4 crystal by micro-milling and modeling of its induced light intensification.
Opt Express
PUBLISHED: 08-14-2013
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Micro-machining is the most promising method for KH(2)PO(4) crystal to mitigate the surface damage growth in high power laser system. In this work, spherical mitigation pit is fabricated by micro-milling with an efficient machining procedure. The light intensification caused by rear surface features before and after mitigation is numerically modeled based on the finite-difference time-domain method. The results indicate that the occurrence of total internal reflections should be responsible for the largest light intensification inside the crystal. For spherical pits after mitigation, the light intensification can be greatly alleviated by preventing the occurrence of total internal reflections. The light intensification caused by spherical mitigation pit is strongly dependent on the width-depth ratio and it is suggested that the width-depth ratio of spherical mitigation pit must be devised to be larger than 5.0 to achieve the minimal light intensification for the mitigation of surface damage growth. Laser damage tests for KH(2)PO(4) crystal validate that the laser damage resistance of initially damaged surface can be retrieved to near the level of ideal surface by replacing initial damage site with predesigned mitigation pit.
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[Content comparison of main chemical compositions in Gardenia jasminoids roasted with ginger juice].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 07-16-2013
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To compare the contents of the main chemical compositions in Gardenia jasminoids before and after being roasted with ginger juice.
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Enhanced production of a novel cytotoxic chromone oxalicumone A by marine-derived mutant Penicillium oxalicum SCSIO 24-2.
Appl. Microbiol. Biotechnol.
PUBLISHED: 07-07-2013
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Many marine natural products hold great potential for the development of new and much needed drugs. However, the production of active metabolites by marine-derived microorganisms is usually very low, and large-scale culture has to be involved to meet the need of chemical structural modification and deep pharmacy study. In order to enhance the production of a novel cytotoxic sulfur-containing chromone oxalicumone A (OA), germinating spores of a marine-derived wild strain Penicillium oxalicum SCSGAF 0023 were mutated by microwave and ultraviolet light irradiation, which led to the obtainment of a mutant P. oxalicum SCSIO 24-2 that could produce fivefold increase in OA production (3.42?±?0.21 mg/l) as compared to the wild strain. This is the first report that germinating spores are applied in marine-derived Penicillium sp. mutating to enhance the production of OA. Further, Plackett-Burman design and central composite design were adopted to optimize the basic medium components for increasing OA production by the mutant SCSIO 24-2 in shake flasks. The results indicated that three medium components including mannitol, maltose, and L-cysteine had significant effects on OA production, and their concentrations were optimized as 36, 27.9, and 0.99 g/l, respectively. In the optimized medium, the OA production (18.31?±?0.27 mg/l) by mutant SCSIO 24-2 was 4.4-fold higher than that in the basic medium. These results of this work promise to improve the present production of OA and may be adopted to enhance other objective products production by marine-derived fungi.
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Asperterrestide A, a cytotoxic cyclic tetrapeptide from the marine-derived fungus Aspergillus terreus SCSGAF0162.
J. Nat. Prod.
PUBLISHED: 06-12-2013
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A new cytotoxic and antiviral cyclic tetrapeptide, asperterrestide A (1), a new alkaloid, terremide C (2), and a new aromatic butenolide, aspernolide E (3), together with 10 known compounds were isolated from the fermentation broth of the marine-derived fungus Aspergillus terreus SCSGAF0162. Their structures were elucidated by spectroscopic analysis, and the absolute configuration of 1 was determined by the Mosher ester technique and analysis of the acid hydrolysates using a chiral-phase HPLC column. Compound 1 contains a rare 3-OH-N-CH3-Phe residue and showed cytotoxicity against U937 and MOLT4 human carcinoma cell lines and inhibitory effects on influenza virus strains H1N1 and H3N2.
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Two important mechanisms damaging KH2PO4 crystal processed by ultraprecision fly cutting and their relationships with cutting parameters.
Appl Opt
PUBLISHED: 06-06-2013
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Mid-frequency waviness and subsurface crack are two fundamental factors that damage KH(2)PO(4) (KDP) crystal processed by ultraprecise fly cutting. In this paper, the motif theory and the Fourier model method are used to analyze the influence of the two factors on the laser-induced damage threshold (LIDT) of KDP. Research results indicate that the modulation degrees increase nearly linearly when the waviness amplitude and subsurface crack depth increase, and, meanwhile, the LIDT tends to decrease. The two factors have different effects during different stages of KDP failure. The mean amplitudes of waviness and subsurface damage depth have similar changing regulations with different feeds. From the machining perspective, we need not necessarily know which is more dangerous, because when one factor is controlled, the other one will also be restrained at the same time. In general, smaller feed and cutting depth are benefits for improving the LIDT of KDP.
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Microtube bundle carbon derived from Paulownia sawdust for hybrid supercapacitor electrodes.
ACS Appl Mater Interfaces
PUBLISHED: 05-29-2013
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The structure and capacitive properties of microtube bundle carbons (MTBCs) from carbonization of paulownia sawdust (PS) followed by NaOH activation were investigated. Morphology analyses indicated that MTBCs had abundant micropores and mesopores with a high specific surface area of about 1900 m(2) g(-1). Cyclic voltammetry, galvanostatic charge/discharge, and electrochemical impedance spectroscopy studies demonstrated the excellent charge storage, transfer capability, and low impedance of MTBCs. The specific capacitance of MTBCs-4 was as high as 227 F g(-1) at 2 mV s(-1). Experimental results indicated that MTBCs provide smooth charge-transfer pathways for the ions in electrolytes and gateways to micropores and mesopores in the bulk. The hybrid supercapacitor model of MTBCs based on electrical double-layer capacitors and electrostatic capacitors was discussed and demonstrated. MTBCs are electrostatic capacitors at low frequency current, and may provide the pathways for easy accessibility of efficient charge transmission and high energy storage.
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Ultrarapid formation of homogeneous Cu6Sn5 and Cu3Sn intermetallic compound joints at room temperature using ultrasonic waves.
Ultrason Sonochem
PUBLISHED: 05-24-2013
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Homogeneous intermetallic compound joints are demanded by the semiconductor industry because of their high melting point. In the present work, ultrasonic vibration was applied to Cu/Sn foil/Cu interconnection system at room temperature to form homogeneous Cu6Sn5 and Cu3Sn joints. Compared with other studies based on transient-liquid-phase soldering, the processing time of our method was dramatically reduced from several hours to several seconds. This ultrarapid intermetallic phase formation process resulted from accelerated interdiffusion kinetics, which can be attributed to the sonochemical effects of acoustic cavitation at the interface between the liquid Sn and the solid Cu during the ultrasonic bonding process.
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Analysis of oxygen reduction and microbial community of air-diffusion biocathode in microbial fuel cells.
Bioresour. Technol.
PUBLISHED: 05-23-2013
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Microbes play irreplaceable role in oxygen reduction reaction of biocathode in microbial fuel cells (MFCs). In this study, air-diffusion biocathode MFCs were set up for accelerating oxygen reduction and microbial community analysis. Linear sweep voltammetry and Tafel curve confirmed the function of cathode biofilm to catalyze oxygen reduction. Microbial community analysis revealed higher diversity and richness of community in plankton than in biofilm. Proteobacteria was the shared predominant phylum in both biofilm and plankton (39.9% and 49.8%) followed by Planctomycetes (29.9%) and Bacteroidetes (13.3%) in biofilm, while Bacteroidetes (28.2%) in plankton. Minor fraction (534, 16.4%) of the total operational taxonomic units (3252) was overlapped demonstrating the disproportionation of bacterial distribution in biofilm and plankton. Pseudomonadales, Rhizobiales and Sphingobacteriales were exoelectrogenic orders in the present study. The research obtained deep insight of microbial community and provided more comprehensive information on uncultured rare bacteria.
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Fabrication of reduced graphene oxide and sliver nanoparticle hybrids for Raman detection of absorbed folic acid: a potential cancer diagnostic probe.
ACS Appl Mater Interfaces
PUBLISHED: 05-23-2013
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Reduced graphene oxide (RGO) and silver nanoparticle (AgNP) hybrids (RGO-AgNP) were prepared by a facile one-pot method using Poly (N-vinyl-2-pyrrolidone) as reductant and stabilizer. Folic acid (FA) molecules were attached to the RGO-AgNP by physisorption for targeting specific cancer cells with folate receptors (FRs) and using as Raman reporter molecules. The internalization of the FA loaded RGO-AgNP (RGO-AgNP-FA) inside the FRs-positive cancer cell was confirmed by confocal laser scanning and transmission electron microscopy. The Raman signals of the FA in live cancer cells were detected by confocal Raman spectroscope at 514 nm excitation, indicating that the RGO-AgNP-FA material has great potential as a Raman probe for cancer diagnosis in vitro.
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Diverse deep-sea fungi from the South China Sea and their antimicrobial activity.
Curr. Microbiol.
PUBLISHED: 05-19-2013
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We investigated the diversity of fungal communities in nine different deep-sea sediment samples of the South China Sea by culture-dependent methods followed by analysis of fungal internal transcribed spacer (ITS) sequences. Although 14 out of 27 identified species were reported in a previous study, 13 species were isolated from sediments of deep-sea environments for the first report. Moreover, these ITS sequences of six isolates shared 84-92 % similarity with their closest matches in GenBank, which suggested that they might be novel phylotypes of genera Ajellomyces, Podosordaria, Torula, and Xylaria. The antimicrobial activities of these fungal isolates were explored using a double-layer technique. A relatively high proportion (56 %) of fungal isolates exhibited antimicrobial activity against at least one pathogenic bacterium or fungus among four marine pathogenic microbes (Micrococcus luteus, Pseudoaltermonas piscida, Aspergerillus versicolor, and A. sydowii). Out of these antimicrobial fungi, the genera Arthrinium, Aspergillus, and Penicillium exhibited antibacterial and antifungal activities, while genus Aureobasidium displayed only antibacterial activity, and genera Acremonium, Cladosporium, Geomyces, and Phaeosphaeriopsis displayed only antifungal activity. To our knowledge, this is the first report to investigate the diversity and antimicrobial activity of culturable deep-sea-derived fungi in the South China Sea. These results suggest that diverse deep-sea fungi from the South China Sea are a potential source for antibiotics discovery and further increase the pool of fungi available for natural bioactive product screening.
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Pioglitazone enhances the blood pressure-lowering effect of losartan via synergistic attenuation of angiotensin II-induced vasoconstriction.
J Renin Angiotensin Aldosterone Syst
PUBLISHED: 05-15-2013
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INTRODUCTION: This study was designed to investigate the underlying mechanisms of synergistic antihypertensive effect produced by combination therapy of losartan and pioglitazone in metabolic syndrome (MS) rats. MATERIALS AND METHODS: An MS model was induced by feeding rats a high-fat, high-sodium diet and 20% sucrose solution. Losartan (20 mg/kg/day), pioglitazone (10 mg/kg/day), and their combination were orally administered for eight consecutive weeks. Systolic blood pressure (SBP) and mean arterial pressure (MAP) were measured using the tail-cuff method and carotid arterial catheterization, respectively. The aortas were isolated and in vitro vascular reactivity studies were performed. The protein expression of angiotensin type 1 receptor (AT1), endothelial nitric oxide synthase (eNOS), phosphorylated eNOS and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase subunit p47(phox), level of nitrotyrosine as well as activity of eNOS and NADPH oxidase in aortas of MS rats were detected. RESULTS: After eight weeks of treatment, the SBP and MAP in the losartan (115 ± 5 and 106 ± 6 mmHg), pioglitazone (130 ± 6 and 118 ± 6 mmHg), and combination therapy (105 ± 6 and 98 ± 5 mmHg) groups were lower than those in the model group (150 ± 8 and 136 ± 9 mmHg). Combination therapy of losartan and pioglitazone reduced BP more than either monotherapy, and showed additive effects on improving endothelial dysfunction and abolishing the increased vascular responsiveness to angiotensin II. These synergistic effects were associated with further reductions in protein expression of p47(phox) and AT1, NADPH oxidase activity, and nitrotyrosine level. CONCLUSIONS: Our data indicate that combined treatment exerts more beneficial effects on lowering BP and improving vascular lesions.
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?B-crystallin complexes with 14-3-3? to induce epithelial-mesenchymal transition and resistance to sorafenib in hepatocellular carcinoma.
Hepatology
PUBLISHED: 05-14-2013
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The overall survival of patients with hepatocellular carcinoma (HCC) remains poor, and the molecular pathogenesis remains incompletely defined in HCC. Here we report that increased expression of ?B-Crystallin in human HCC predicts poor survival and disease recurrence after surgery. Multivariate analysis identifies ?B-Crystallin expression as an independent predictor for postoperative recurrence and overall survival. We show that elevated expression of ?B-Crystallin promotes HCC progression in vivo and in vitro. We demonstrate that ?B-Crystallin overexpression fosters HCC progression by inducing epithelial-mesenchymal transition (EMT) in HCC cells through activation of the extracellular-regulated protein kinase (ERK) cascade, which can counteract the effect of sorafenib. ?B-Crystallin complexes with and elevates 14-3-3? protein, leading to up-regulation of ERK1/2 activity. Moreover, overexpression of ?B-Crystallin in HCC cells induces EMT progression through an ERK1/2/Fra-1/slug signaling pathway. Clinically, our data reveal that overexpression of both ?B-Crystallin and 14-3-3? correlates with the HCC poorest survival outcomes, and sorafenib response is impaired in patients with ?B-Crystallin overexpression. Conclusion: These data suggest that the ?B-Crystallin-14-3-3? complex acts synergistically to promote HCC progression by constitutively activating ERK signaling. This study reveals ?B-Crystallin as a potential therapeutic target for HCC and a biomarker for predicting sorafenib treatment response. (HEPATOLOGY 2013).
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Xylazine-induced reduction of tissue sensitivity to insulin leads to acute hyperglycemia in diabetic and normoglycemic monkeys.
BMC Anesthesiol
PUBLISHED: 05-02-2013
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The alpha2-adrenoceptor agonist xylazine as an anesthetic has been widely used either alone or in combination with other anesthetics, such as ketamine, in veterinary clinic and research. In the last decade xylazine has been used in drug abusers in certain geographic area. This study investigated the effects of xylazine on blood glucose level and insulin secretion in normoglycemic and insulin-dependent diabetic monkeys.
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Alkaloids from the deep-sea-derived fungus Aspergillus westerdijkiae DFFSCS013.
J. Nat. Prod.
PUBLISHED: 04-26-2013
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Two new benzodiazepine alkaloids, circumdatins K and L (1, 2), two new prenylated indole alkaloids, 5-chlorosclerotiamide (3) and 10-epi-sclerotiamide (4), and one novel amide, aspergilliamide B (5), together with six known alkaloids were isolated from the deep-sea-derived fungus Aspergillus westerdijkiae DFFSCS013. Their structures were elucidated by extensive spectroscopic analysis. All of the compounds were tested for cytotoxicity toward human carcinoma A549, HL-60, K562, and MCF-7 cell lines.
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[Screening of pregnane X receptor activation from ginsenosides].
Yao Xue Xue Bao
PUBLISHED: 04-23-2013
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In order to study effects of ginseng on the metabolism of drug belong to CYP3A4 substrate, screening of pregnane X receptor activation from ginsenosides was performed by reporter assay. Based on PXR-CYP3A stable translation cell lines, 13 ginsenosides were screened for pregnane X receptor activation by reporter assays, and RIF as the positive control. The effect of ginsenosides Rg1 onCYP3A4 mRNA expression was also investigated by RT-PCR. The PXR-CYP3A stable translation cell lines had good response to RIF, and the EC50 is 2.51 micro mol x L(-1). When the condition of final concentration was 10 micromol x L(-1), ginsenoside F2 and protopanaxatriol had moderate inductive effects on PXR. Panaxotriol, Rg2, pseudoginsenoside F11, Rg1, ginsenoside and Rb3 had inhibitory effects on PXR. Ginsenoside Rf1, Rg3, Rh2 and protopanaxdiol had no obvious effects on PXR. Rg1 down-regulated CYP3A4 mRNA expression in a concentration-dependent manner. Activation of pregnane X receptor by ginsenosides may influence the metabolism of drug belong to CYP3A4 substrate, and cause ginseng-drug interactions.
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Do scientists trace hot topics?
Sci Rep
PUBLISHED: 03-22-2013
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Do scientists follow hot topics in their scientific investigations? In this paper, by performing analysis to papers published in the American Physical Society (APS) Physical Review journals, it is found that papers are more likely to be attracted by hot fields, where the hotness of a field is measured by the number of papers belonging to the field. This indicates that scientists generally do follow hot topics. However, there are qualitative differences among scientists from various countries, among research works regarding different number of authors, different number of affiliations and different number of references. These observations could be valuable for policy makers when deciding research funding and also for individual researchers when searching for scientific projects.
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Reactive oxygen species induce a Ca(2+)-spark increase in sensitized murine airway smooth muscle cells.
Biochem. Biophys. Res. Commun.
PUBLISHED: 03-22-2013
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The level of reactive oxygen species (ROS) and the activity of spontaneous, transient, localized Ca(2+) increases (known as Ca(2+) sparks) in tracheal smooth muscle cells (TSMCs) in an experimental allergic asthma mouse model has not yet been investigated. We used laser confocal microscopy and fluorescent dyes to measure ROS levels and Ca(2+) sparks, and we found that both events were significantly increased in TSMCs obtained from ovalbumin (OVA)-sensitized/-challenged mice compared with control mice. ROS levels began to increase in TSMCs after the first OVA challenge, and this increase was sustained. However, this elevation and Ca(2+)-spark increase was abolished after the administration of the ROS scavenger N-acetylcysteine amide (NACA) for 5days. Furthermore, a similar inhibition was also observed following the direct perfusion of NACA into cells isolated from the (OVA)-sensitized mice that were not treated with NACA. Moreover, we used 0.1-mM caffeine treatment to increase the Ca(2+) sparks in single TSMCs and observed cell shortening. In addition, we did not find increases in the mRNA levels of ryanodine (RyRs) and inositol 1,4,5-trisphosphate (IP3Rs) receptors in the tracheal smooth muscle cells of (OVA)-sensitized mice compared with controls. We concluded that ROS and Ca(2+) sparks increased in (OVA)-sensitized TSMCs. We found that ROS induces Ca(2+) sparks, and increased Ca(2+) sparks resulted in the contraction of (OVA)-sensitized TSMCs, resulting in the generation of airway hyperresponsiveness (AHR). This effect may represent a novel mechanism for AHR pathogenesis and might provide insight into new methods for the clinical prevention and treatment of asthma and asthmatic AHR.
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In situ probing the effect of potentials on the microenvironment of heterotrophic denitrification biofilm with microelectrodes.
Chemosphere
PUBLISHED: 03-21-2013
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Bio-electrochemical reactor provides a promising technology to remove nitrogen contaminants in water. In this study, a heterotrophic biofilm for denitrification process was developed, and stable total nitrogen removal efficiencies (>80%) were achieved. Fluorescence in situ hybridization showed that genes norB mainly transcribed in inner biofilm while genes nosZ showed similar transcription activities in the entire biofilm. The microelectrodes of pH and nitrous oxide (N?O) were applied to profile the microenvironment of denitrification biofilm. In all measurements, the microenvironment pH decreased as a function of biofilm depth. The highest N?O concentration of 90 ?M in biofilm was detected when the bulk solution pH was 7.3, and an applied potential of -0.2V did not decrease the yield of N?O in biofilm at pH 7.3. Nevertheless, pH 9.5 or an applied potential of -0.4V seemed not to suppress the yield of N?O in biofilm.
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Polyketides from a marine-derived fungus Xylariaceae sp.
Mar Drugs
PUBLISHED: 03-19-2013
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Eighteen polyketides (1-18) including six citrinin derivatives, two phenol derivatives, one cyclopentenone, two naphthol derivatives, and seven tetralone derivatives were isolated from the culture broth of a marine-derived fungal strain Xylariaceae sp. SCSGAF0086. Five of these compounds (1, 2, 8, 9, and 10) were new, and their structures were determined by spectroscopic methods. Compounds 4, 6, 7, and 17 showed enzyme-inhibitory activities towards several tested enzymes, and 6 and 7 showed strong antifouling activity against Bugula neritina larvae settlement. This is the first time that the antifouling and enzyme-inhibitory activities of these compounds has been reported.
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[Impact of aging on the secretion of insulin-like growth factor-1 in the corpus cavernosum smooth muscle cells of rats in vitro].
Zhonghua Nan Ke Xue
PUBLISHED: 03-09-2013
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To observe the secretion of insulin-like growth factor-1 (IGF-1) in corpus cavernosum smooth muscle cells (CCSMCs) in rats of different ages and explore the possible relationship of IGF-1 with aging-related erectile dysfunction (ED).
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RNA-Seq analysis of Cocos nucifera: transcriptome sequencing and de novo assembly for subsequent functional genomics approaches.
PLoS ONE
PUBLISHED: 02-20-2013
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Cocos nucifera (coconut), a member of the Arecaceae family, is an economically important woody palm grown in tropical regions. Despite its agronomic importance, previous germplasm assessment studies have relied solely on morphological and agronomical traits. Molecular biology techniques have been scarcely used in assessment of genetic resources and for improvement of important agronomic and quality traits in Cocos nucifera, mostly due to the absence of available sequence information.
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Distinct activity of BK channel ?1-subunit in cerebral and pulmonary artery smooth muscle cells.
Am. J. Physiol., Cell Physiol.
PUBLISHED: 02-20-2013
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This study was designed to test a hypothesis that the functional activity of big-conductance, Ca(2+)-activated K(+) (BK) channels is different in cerebral and pulmonary artery smooth muscle cells (CASMCs and PASMCs). Using patch-clamp recordings, we found that the activity of whole cell and single BK channels were significantly higher in CASMCs than in PASMCs. The voltage and Ca(2+) sensitivity of BK channels were greater in CASMCs than in PASMCs. Targeted gene knockout of ?(1)-subunits significantly reduced BK currents in CASMCs but had no effect in PASMCs. Western blotting experiments revealed that BK channel ?-subunit protein expression level was comparable in CASMCs and PASMCs; however, ?(1)-subunit protein expression level was higher in CASMCs than in PASMCs. Inhibition of BK channels by the specific blocker iberiotoxin enhanced norepinephrine-induced increase in intracellular calcium concentration in CASMCs but not in PASMCs. Systemic artery blood pressure was elevated in ?(1)(-/-) mice. In contrast, pulmonary artery blood pressure was normal in ?(1)(-/-) mice. These findings provide the first evidence that the activity of BK channels is higher in cerebral than in PASMCs. This heterogeneity is primarily determined by the differential ?(1)-subunit function and contributes to diverse cellular responses in these two distinct types of cells.
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Treatment of aganglionic megacolon mice via neural stem cell transplantation.
Mol. Neurobiol.
PUBLISHED: 02-17-2013
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To explore a potential methodology for treating aganglionic megacolon, neural stem cells (NSCs) expressing engineered endothelin receptor type B (EDNRB) and glial cell-derived neurotrophic factor (GDNF) genes were transplanted into the aganglionic megacolon mice. After transplantation, the regeneration of neurons in the colon tissue was observed, and expression levels of differentiation-related genes were determined. Primary culture of NSCs was obtained from the cortex of postnatal mouse brain and infected with recombinant adenovirus expressing EDNRB and GDNF genes. The mouse model of aganglionic megacolon was developed by treating the colon tissue with 0.5 % benzalkonium chloride (BAC) to selectively remove the myenteric nerve plexus that resembles the pathological changes in the human congenital megacolon. The NSCs stably expressing the EDNRB and GDNF genes were transplanted into the benzalkonium chloride-induced mouse aganglionic colon. Survival and differentiation of the implanted stem cells were assessed after transplantation. Results showed that the EDNRB and GDNF genes were able to be expressed in primary culture of NSCs by adenovirus infection. One week after implantation, grafted NSCs survived and differentiated into neurons. Compared to the controls, elevated expression of EDNRB and GDNF was determined in BAC-induced aganglionic megacolon mice with partially improved intestinal function. Those founding indicated that the genes transfected into NSCs were expressed in vivo after transplantation. Also, this study provided favorable support for the therapeutic potential of multiple gene-modified NSC transplantation to treat Hirschsprungs disease, a congenital disorder of the colon in which ganglion cells are absent.
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Diversity of individual mobility patterns and emergence of aggregated scaling laws.
Sci Rep
PUBLISHED: 02-04-2013
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Uncovering human mobility patterns is of fundamental importance to the understanding of epidemic spreading, urban transportation and other socioeconomic dynamics embodying spatiality and human travel. According to the direct travel diaries of volunteers, we show the absence of scaling properties in the displacement distribution at the individual level,while the aggregated displacement distribution follows a power law with an exponential cutoff. Given the constraint on total travelling cost, this aggregated scaling law can be analytically predicted by the mixture nature of human travel under the principle of maximum entropy. A direct corollary of such theory is that the displacement distribution of a single mode of transportation should follow an exponential law, which also gets supportive evidences in known data. We thus conclude that the travelling cost shapes the displacement distribution at the aggregated level.
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A high-confidence interaction map identifies SIRT1 as a mediator of acetylation of USP22 and the SAGA coactivator complex.
Mol. Cell. Biol.
PUBLISHED: 02-04-2013
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Although many functions and targets have been attributed to the histone and protein deacetylase SIRT1, a comprehensive analysis of SIRT1 binding proteins yielding a high-confidence interaction map has not been established. Using a comparative statistical analysis of binding partners, we have assembled a high-confidence SIRT1 interactome. Employing this method, we identified the deubiquitinating enzyme ubiquitin-specific protease 22 (USP22), a component of the deubiquitinating module (DUBm) of the SAGA transcriptional coactivating complex, as a SIRT1-interacting partner. We found that this interaction is highly specific, requires the ZnF-UBP domain of USP22, and is disrupted by the inactivating H363Y mutation within SIRT1. Moreover, we show that USP22 is acetylated on multiple lysine residues and that alteration of a single lysine (K129) within the ZnF-UBP domain is sufficient to alter interaction of the DUBm with the core SAGA complex. Furthermore, USP22-mediated recruitment of SIRT1 activity promotes the deacetylation of individual SAGA complex components. Our results indicate an important role of SIRT1-mediated deacetylation in regulating the formation of DUBm subcomplexes within the larger SAGA complex.
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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.