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Find video protocols related to scientific articles indexed in Pubmed.
Boundary integral spectral element method analyses of extreme ultraviolet multilayer defects.
J Opt Soc Am A Opt Image Sci Vis
PUBLISHED: 11-18-2014
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Extreme ultraviolet (EUV) lithography is an emerging technology for high-density semiconductor patterning. Multilayer distortion caused by mask defects is regarded as one of the critical challenges of EUV lithography. To simulate the influence of the defected nanoscale structures with high accuracy and efficiency, we have developed a boundary integral spectral element method (BI-SEM) that combines the SEM with a set of surface integral equations. The SEM is used to solve the interior computational domain, while the open boundaries are truncated by the surface integral equations. Both two-dimensional (2D) and three-dimensional (3D) EUV cases are simulated. Through comparing the performance of this method with the conventional finite element method (FEM), it is shown that the proposed BI-SEM can greatly decrease both the memory cost and the computation time. For typical 2D problems, we show that the BI-SEM is 11 and 1.25 times more efficient than the FEM in terms of memory and CPU time, respectively, while for 3D problems, these factors are over 14 and 2, respectively, for smaller problems; realistic 3D problems that cannot be solved by the conventional FEM can be accurately simulated by the BI-SEM.
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Effect of Salts on Formation and Stability of Vitamin E-Enriched Mini-emulsions Produced by Spontaneous Emulsification.
J. Agric. Food Chem.
PUBLISHED: 11-11-2014
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Emulsion-based delivery systems are being utilized to incorporate lipophilic bioactive components into various food, personal care, and pharmaceutical products. This study examined the influence of inorganic salts (NaCl and CaCl2) on the formation, stability, and properties of vitamin E-enriched emulsions prepared by spontaneous emulsification. These emulsions were simply formed by titration of a mixture of vitamin E acetate (VE), carrier oil (MCT), and nonionic surfactant (Tween 80) into an aqueous salt solution with continuous stirring. Salt type and concentration (0-1 N NaCl or 0-0.5 N CaCl2) did not have a significant influence on the initial droplet size of the emulsions. On the other hand, the isothermal and thermal stabilities of the emulsions depended strongly on salt levels. The cloud point of the emulsions decreased with increasing salt concentration, which was attributed to accelerated droplet coalescence in the presence of salts. Dilution (2-6 times) of the emulsions with water appreciably improved their thermal stability by increasing their cloud point, which was mainly attributed to the decrease in aqueous phase salt levels. The isothermal storage stability of the emulsions also depended on salt concentration; however, increasing the salt concentration decreased the rate of droplet growth, which was the opposite of its effect on thermal stability. Potential physicochemical mechanisms for these effects are discussed in terms of the influence of salt ions on van der Waals and electrostatic interactions. This study provides important information about the effect of inorganic salts on the formation and stability of vitamin E emulsions suitable for use in food, personal care, and pharmaceutical products.
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Correlation analysis of computed tomography imaging score with the presence of acute kidney injury in severe acute pancreatitis.
Abdom Imaging
PUBLISHED: 11-05-2014
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The aim of the study is to investigate the CT imaging findings of severe acute pancreatitis (SAP) complicated with acute kidney injury (AKI) and evaluate the correlation between the CT imaging score and the presence of AKI in SAP.
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Cryptotanshinone Ameliorates Hepatic Normothermic Ischemia and Reperfusion Injury in Rats by Anti-mitochondrial Apoptosis.
Biol. Pharm. Bull.
PUBLISHED: 11-05-2014
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Cryptotanshinone (CT), isolated from the dried roots of Salvia militorrhiza, has been reported to have protective effects on myocardial and cerebral ischemia/reperfusion (I/R) injury both in vitro and in vivo. However, its effects and underlying mechanism on hepatic I/R injury remain unclear. To investigate its effects on hepatic I/R injury, thirty male Sprague-Dawley rats were randomized into 3 groups: a sham group, a vehicle-treated hepatic I/R group and a CT-treated (50?mg/kg) group. The hepatic I/R and CT-treated groups were subjected to 60?min of normothermic ischemia of the left lateral lobe of the liver, followed by 4?h of reperfusion. The animals were then sacrificed to collect the serum and the left liver lobe for assay. Hepatic function was protected, as evidenced by significantly reduced alanine aminotransferase (ALT), aspartate aminotransferase (AST) and malondialdehyde (MDA) levels in the CT-treated group as compared with I/R group. The terminal deoxynucleotidyl transferase deoxyuridine triphosphate (dUTP) nick end labeling (TUNEL) demonstrated significantly decreased apoptosis in the CT-administration animals. Western blotting demonstrated upregulation of the proapoptotic protein Bcl-2, as well as decreased levels of the activated form of caspase-3 and the cleaved form of its substrate, poly(ADP-ribose) polymerase (PARP) in the CT-treated group compared with those of the I/R group. In addition, the phosphorylation of c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinases (MAPKs) was inhibited by CT. Our data suggest that CT attenuates hepatic I/R injury by inhibiting the intrinsic pathway of apoptosis, mediated partly through the inhibition of JNK and p38 MAPK phosporylation.
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HERC2-USP20 axis regulates DNA damage checkpoint through Claspin.
Nucleic Acids Res.
PUBLISHED: 10-31-2014
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The DNA damage response triggers cell-cycle checkpoints, DNA repair and apoptosis using multiple post-translational modifications as molecular switches. However, how ubiquitination regulates ATR signaling in response to replication stress and single-strand break is still unclear. Here, we identified the deubiquitination enzyme (DUB) USP20 as a pivotal regulator of ATR-related DDR pathway. Through screening a panel of DUBs, we identified USP20 as critical for replication stress response. USP20 is phosphorylated by ATR, resulting in disassociation of the E3 ubiquitin ligase HERC2 from USP20 and USP20 stabilization. USP20 in turn deubiquitinates and stabilizes Claspin and enhances the activation of ATR-Chk1 signaling. These findings reveal USP20 to be a novel regulator of ATR-dependent DNA damage signaling.
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Native and Thermally Modified Protein-Polyphenol Coassemblies: Lactoferrin-Based Nanoparticles and Submicrometer Particles as Protective Vehicles for (-)-Epigallocatechin-3-gallate.
J. Agric. Food Chem.
PUBLISHED: 10-21-2014
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The interactions between native, thermally modified lactoferrin (LF) and (-)-epigallocatechin-3-gallate (EGCG) at pH 3.5, 5.0, and 6.5 were investigated. Turbidity, particle size, and charge of LF-EGCG complexes were mainly dominated by pH value and secondary structure of protein. At pH 3.5 and 5.0, LF-EGCG complexes were nanoparticles which had high ?-potential, small size, and soluble state. At pH 6.5, they were submicrometer particles which exhibited low ?-potential, large size, and insoluble state. The infrared spectra of freeze-dried LF-EGCG complexes showed that they were different from LF and EGCG alone. Far-UV CD results indicated that heat denaturation might irreversibly alter the secondary structure of LF and EGCG induced a progressive increase in the proportion of ?-helix structure at the cost of ?-sheet and unordered coil structure of LF at pH 3.5, 5.0, and 6.5. EGCG exhibited a strong affinity for native LF but a weak affinity for thermally modified LF at pH 5.0 and 6.5. An inverse result was observed at pH 3.5. These results could have potential for the development of food formulations based on LF as a carrier of bioactive compounds.
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Association between miR34b/c polymorphism rs4938723 and cancer risk: a meta-analysis of 11 studies including 6169 cases and 6337 controls.
Med. Sci. Monit.
PUBLISHED: 10-20-2014
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The functional polymorphism rs4938723 in the promoter region of pri-miR-34b/c is potentially associated with susceptibility to several cancers, including hepatocellular carcinoma, colorectal cancer, and breast cancer. Here we conducted a comprehensive meta-analysis to investigate the association between rs4938723 and cancer risk.
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Differential detection of Rhizoma coptidis by capillary electrophoresis electrospray ionization mass spectrometry with a nanospray interface.
Electrophoresis
PUBLISHED: 10-02-2014
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A lab prototype CE-nanospray-MS platform with a high sensitivity porous sprayer was successfully applied in differential identification of Rhizoma coptidis in this paper. To obtain a stable and reliable nanospray, detailed optimizations about emitter geometry, buffer composition, emitter position, and spray voltage, as well as emitter cleanliness were discussed. Results showed that the reproducibility and sensitivity for separations of alkaloid standards were satisfactory using CE-nanospray-MS, which were also compared to ultra-HPLC (UHPLC)-MS. Their signal responds were at the same order of magnitude (intensities: 0.8 - 1.5 × 10(8) vs. 3.8 - 6.2 × 10(8) ), even though a 2 nL injection for CE was 2500-fold lower than UHPLC (5 ?L injection). The absolute LOD results of CE-MS showed a remarkable superiority (18-24 fg), equal to 1000-fold lower than that of UHPLC-MS. Principal component analysis (PCA) of adulterated R. coptidis showed that this protocol had the ability to profile and qualify complex herb medicines, which also created a great potential for evaluation and qualification of rare and valuable Chinese medicines in future.
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Intracystic bleomycin for cystic craniopharyngiomas in children.
Cochrane Database Syst Rev
PUBLISHED: 09-20-2014
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Craniopharyngiomas are the commonest benign histological tumours to involve the hypothalamo-pituitary region in childhood. Cystic craniopharyngiomas comprise more than 90% of the tumours. The optimal treatment of cystic craniopharyngioma remains controversial. Radical resection is the treatment of choice in patients with favourable tumour localisation. When the tumour localisation is unfavourable, a gross-total or partial resection followed by radiotherapy is the main treatment option in adults. However, it presents a risk of morbidity, especially for children. Intracystic bleomycin has been utilised potentially to delay the use of radiotherapy or radical resection, to decrease morbidity. This review is an update of a previously published Cochrane review.
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Effects of milk proteins on release properties and particle morphology of ?-carotene emulsions during in vitro digestion.
Food Funct
PUBLISHED: 09-13-2014
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In the present study, ?-lactoglobulin, sodium caseinate, lactalbumin and lactoferrin were used to prepare ?-carotene emulsions. The milk protein-stabilized emulsions were explored using an in vitro release model to elucidate the effects of different milk proteins on ?-carotene release properties in the stomach, duodenum and small intestine, respectively. Notable changes in the droplet size and size distribution were observed among these four oil-in-water (O/W) milk protein emulsions. In the gastric environment, the highest ?-carotene release rate (2.9%) was achieved in ?-lactoglobulin emulsion with a remarkable change in the particle size. In the simulated intestine, the best ?-carotene micellarization potency (92%) was observed in ?-lactoglobulin emulsion and its droplet diameter moderately increased from 215 nm to 471 nm. Moreover, substantial release of ?-carotene was found in the small intestine for the four types of emulsions. It was concluded that ?-carotene release in different digestive stages was characterized by the emulsion interfacial composition.
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TSC1-mTORC1 signaling determines brown-to-white adipocyte phenotypic switch.
Diabetes
PUBLISHED: 09-13-2014
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Interconversion of white and brown adipocytes occurs between anabolic and catabolic states. The molecular mechanism regulating this phenotypic switch remains largely unknown. This study explores the role of tuberous sclerosis complex 1 (TSC1)-mechanistic target of rapamycin (mTOR) signaling in the conversion of brown to white adipose tissue. A colony of Fabp4-Tsc1-/- mice, in which the Tsc1 gene was specifically deleted by the fatty acid binding protein 4 (FABP4)-Cre, was established. Western blotting and immunostaining demonstrated the absence of TSC1 and activation of ribosomal protein S6 kinase 1, the downstream target of mTOR complex 1 (mTORC1) signaling, in the brown adipose tissues (BAT) of Fabp4-Tsc1-/- mice. Accumulation of lipid droplets in BAT was significantly increased. Levels of brown adipocyte markers were markedly down-regulated, while white adipocyte markers up-regulated. Rapamycin reversed the conversion from BAT to WAT in Fabp4-Tsc1-/- mice. Deletion of Tsc1 gene in cultured brown preadipocytes significantly increased the conversion to white adipocytes. FoxC2 mRNA, the transcriptional factor for brown adipocyte determination, was significantly decreased, while mRNAs for Rb, p107 and RIP140, the transcriptional factors for white adipocyte determination, increased in the BAT of Fabp4-Tsc1-/- mice. Our study demonstrates that TSC1-mTORC1 signaling contributes to the brown-to-white adipocyte phenotypic switch.
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Hemilaminoplasty for the treatment of lumbar intraspinal synovial cysts (LISCs) and literature review.
Eur Spine J
PUBLISHED: 09-04-2014
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The present report intended to introduce the hemilaminoplasty technique and evaluate the efficacy of our surgical procedure for LISCs.
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High glucose-induced Galectin-1 in human podocytes implicates the involvement of Galectin-1 in diabetic nephropathy.
Cell Biol. Int.
PUBLISHED: 09-02-2014
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The diabetic milieu is believed to change the activity, or result in damage of podocytes-a key component of the glomerular filtration barrier and known to secrete matrix for glomerular basement membrane. This in turn contributes to diabetic nephropathy. However, how podocyte dysfunction is triggered in diabetic nephropathy remains ambiguous. Galectin-1 belongs to Galectin family that bind to ?-galactoside residues of glycosylated proteins. We explored whether Galectin-1 is dysregulated in diabetic nephropathy using three different techniques, namely real-time polymerase chain reaction, western blotting, and immunofluorescent staining, to follow the expression of Galectin-1 under high glucose levels in podocytes. High glucose consistently induced Galectin-1 expression. Immunohistochemistry using a Galectin-1-specific antibody also showed elevated Galectin-1 in renal tissues of diabetic patients with manifestation of nephropathy, indicating a correlation of Galectin-1 overexpression with diabetic nephropathy. Upregulation of Galectin-1 is associated with loss of podocin, which is important for the physiological function of podocytes and decreases in the renal tissues of diabetic nephropathy. Increased Galectin-1 is a causal event for the high glucose-induced loss of podocin, since silencing Galectin-1 in podocytes increased podocin expression in the presence of 25?mM glucose. Thus expression of Galectin-1 in diabetic nephropathy may serve as a marker and contribute to disease progression by interfering with podocin expression.
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[Etiological study on cases with viral diarrhea in Ningxia during 2011].
Zhonghua Liu Xing Bing Xue Za Zhi
PUBLISHED: 09-02-2014
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To investigate the etiological characteristics of human rotavirus (HRV), human calicivirus (HuCV), human astrovirus (HAstV) and human enteral adenovirus (HAdV) in Ningxia province during 2011.
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OSCA1 mediates osmotic-stress-evoked Ca2+ increases vital for osmosensing in Arabidopsis.
Nature
PUBLISHED: 08-27-2014
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Water is crucial to plant growth and development. Environmental water deficiency triggers an osmotic stress signalling cascade, which induces short-term cellular responses to reduce water loss and long-term responses to remodel the transcriptional network and physiological and developmental processes. Several signalling components that have been identified by extensive genetic screens for altered sensitivities to osmotic stress seem to function downstream of the perception of osmotic stress. It is known that hyperosmolality and various other stimuli trigger increases in cytosolic free calcium concentration ([Ca(2+)]i). Considering that in bacteria and animals osmosensing Ca(2+) channels serve as osmosensors, hyperosmolality-induced [Ca(2+)]i increases have been widely speculated to be involved in osmosensing in plants. However, the molecular nature of corresponding Ca(2+) channels remain unclear. Here we describe a hyperosmolality-gated calcium-permeable channel and its function in osmosensing in plants. Using calcium-imaging-based unbiased forward genetic screens we isolated Arabidopsis mutants that exhibit low hyperosmolality-induced [Ca(2+)]i increases. These mutants were rescreened for their cellular, physiological and developmental responses to osmotic stress, and those with clear combined phenotypes were selected for further physical mapping. One of the mutants, reduced hyperosmolality-induced [Ca(2+)]i increase 1 (osca1), displays impaired osmotic Ca(2+) signalling in guard cells and root cells, and attenuated water transpiration regulation and root growth in response to osmotic stress. OSCA1 is identified as a previously unknown plasma membrane protein and forms hyperosmolality-gated calcium-permeable channels, revealing that OSCA1 may be an osmosensor. OSCA1 represents a channel responsible for [Ca(2+)]i increases induced by a stimulus in plants, opening up new avenues for studying Ca(2+) machineries for other stimuli and providing potential molecular genetic targets for engineering drought-resistant crops.
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Nitrogen-doped one-dimensional (1D) macroporous carbonaceous nanotube arrays and their application in electrocatalytic oxygen reduction reactions.
Nanoscale
PUBLISHED: 08-23-2014
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A nitrogen(N)-doped one-dimensional (1D) macroporous carbonaceous nanotube array was fabricated by using an anodic alumina oxide (AAO) template. The large diameter of the nanotubes (?200 nm) could overcome the sluggish mass transfer phenomena in the common micro/mesoporous carbon-based electrodes. Combining the activation of the ? electrons of the sp(2) carbon array by N-doping, the novel 1D macroporous carbonaceous nanotube array exhibited high performance for the oxygen reduction reaction (ORR).
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High speed all optical Nyquist signal generation and full-band coherent detection.
Sci Rep
PUBLISHED: 08-21-2014
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Spectrum efficient data transmission is of key interest for high capacity optical communication systems considering the limited available bandwidth. Transmission of the high speed signal with higher-order modulation formats within the Nyquist bandwidth using coherent detection brings attractive performance advantages. However, high speed Nyquist signal generation with high order modulation formats is challenging. Electrical Nyquist pulse generation is restricted by the limited sampling rate and processor capacities of digital-to-analog convertor devices, while the optical Nyquist signals can provide a much higher symbol rate using time domain multiplexing method. However, most optical Nyquist signals are based on direct detection with simple modulation formats. Here we report the first experimental demonstration of high speed all optical Nyquist signal generation based on Sinc-shaped pulse generation and time-division multiplexing with high level modulation format and full-band coherent detection. Our experiments demonstrate a highly flexible and compatible all optical high speed Nyquist signal generation and detection scheme for future fiber communication systems.
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Effect of p27 gene combined with Pientzehuang () on tumor growth in osteosarcoma-bearing nude mice.
Chin J Integr Med
PUBLISHED: 08-20-2014
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To observe the effect of p27 gene recombinant adenovirus combined with Chinese medicine Pientzehuang () on the growth of xenografted human osteosarcoma in nude mice.
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Corilagin Protects Against HSV1 Encephalitis Through Inhibiting the TLR2 Signaling Pathways In Vivo and In Vitro.
Mol. Neurobiol.
PUBLISHED: 08-19-2014
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In this study, we tried to explore the molecular mechanism that Corilagin protected against herpes simplex virus-1 encephalitis through inhibiting the TLR2 signaling pathways in vivo and in vitro. As a result, Corilagin significantly prevented increase in the levels of TLR2 and its downstream mediators following Malp2 or HSV-1 challenge. On the other hand, in spite of TLR2 knockdown, Corilagin could still significantly suppress the expression of P38 and NEMO, phosphor-P38, and nuclear factor kappa B. The mRNA and protein expression of TLR2 and its downstream mediators in the brain tissue were also significantly lowered in mice treated with Corilagin. In addition, Corilagin inhibited expression of tumor necrosis factor-? (TNF-?) and interleukin (IL)-6 protein. In conclusion, Corilagin shows the potential to protect against HSV-1-induced encephalitis, and the beneficial effects may be mediated by inhibiting TLR2 signaling pathways.
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Ultrahigh-capacity access network architecture for mobile data backhaul using integrated W-band wireless and free-space optical links with OAM multiplexing.
Opt Lett
PUBLISHED: 08-15-2014
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In this Letter, we propose and experimentally demonstrate a novel access network architecture using hybrid integrated W-band wireless and free-space optical (FSO) links with orbital angular momentum (OAM) multiplexing. The transmission of a 20 GBd quadrature phase-shift keying signal modulated over 10 OAM modes has been demonstrated over a 0.6 m FSO link and a 0.4 m W-band wireless link at 100 GHz. The experimental results show that the architecture can support future ultrahigh-capacity, converged optical-wireless access networks that require extra bandwidth and system flexibility in mobile data networks.
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GATA6 loss-of-function mutations contribute to familial dilated cardiomyopathy.
Int. J. Mol. Med.
PUBLISHED: 08-13-2014
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Dilated cardiomyopathy (DCM), the most prevalent form of primary heart muscle disease, is the third most common cause of heart failure and the most frequent reason for cardiac transplantation. Mounting evidence has demonstrated that genetic risk factors are crucial in the pathogenesis of DCM. However, DCM is genetically heterogeneous, and the genetic basis of DCM in a large majority of cases remains unclear. In the current study, the coding exons and flanking introns of the GATA6 gene, which encodes a zinc?finger transcription factor essential for cardiogenesis, was sequenced in 140 unrelated patients with DCM, and two novel heterozygous mutations, p.C447Y and p.H475R, were identified in two index patients with DCM, respectively. Analysis of the pedigrees showed that in each family the mutation co-segregated with DCM transmitted in an autosomal-dominant pattern, with complete penetrance. The missense mutations were absent in 400 control chromosomes and predicted to be disease-causing by MutationTaster or probably damaging by PolyPhen-2. The alignment of multiple GATA6 proteins across species revealed that the altered amino acids were completely conserved evolutionarily. The functional assays showed that the mutated GATA6 proteins were associated with significantly reduced transcriptional activation in comparison with their wild-type counterpart. To the best of our knowledge, this is the first study on the association of GATA6 loss-of-function mutations with enhanced susceptibility to familial DCM, which provides novel insight into the molecular mechanism of DCM and suggests potential implications for the antenatal prophylaxis and allele-specific treatment of DCM.
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Evolution of oleosin in land plants.
PLoS ONE
PUBLISHED: 08-08-2014
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Oleosins form a steric barrier surface on lipid droplets in cytoplasm, preventing them from contacting and coalescing with adjacent droplets. Oleosin genes have been detected in numerous plant species. However, the presence of oleosin genes in the most basally diverging lineage of land plants, liverworts, has not been reported previously. Thus we explored whether liverworts have an oleosin gene. In Marchantia polymorpha L., a thalloid liverwort, one predicted sequence was found that could encode oleosin, possessing the hallmark of oleosin, a proline knot (-PX5SPX3P-) motif. The phylogeny of the oleosin gene family in land plants was reconstructed based on both nucleotide and amino acid sequences of oleosins, from 31 representative species covering almost all the main lineages of land plants. Based on our phylogenetic trees, oleosin genes were classified into three groups: M-oleosins (defined here as a novel group distinct from the two previously known groups), low molecular weight isoform (L-oleosin), and high molecular weight isoform (H-oleosin), according to their amino-acid organization, phylogenetic relationships, expression tissues, and immunological characteristics. In liverworts, mosses, lycophytes, and gymnosperms, only M-oleosins have been described. In angiosperms, however, while this isoform remains and is highly expressed in the gametophyte pollen tube, two other isoforms also occur, L-oleosins and H-oleosins. Phylogenetic analyses suggest that the M-oleosin isoform is the precursor to the ancestor of L-oleosins and H-oleosins. The later two isoforms evolved by successive gene duplications in ancestral angiosperms. At the genomic level, most oleosins possess no introns. If introns are present, in both the L-isoform and the M-isoform a single intron inserts behind the central region, while in the H-isoform, a single intron is located at the 5'-terminus. This study fills a major gap in understanding functional gene evolution of oleosin in land plants, shedding new light on evolutionary transitions of lipid storage strategies.
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Tuning the Optoelectronic Properties of Nonfullerene Electron Acceptors.
Chemphyschem
PUBLISHED: 08-06-2014
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Broad spectral coverage over the solar spectrum is necessary for photovoltaic technologies and is a focus for organic solar cells. We report a series of small-molecule, nonfullerene electron acceptors containing the [(benzo[c][1,2,5]thiadiazol-4-yl)methylene]malononitrile unit as a high electron affinity component. The optoelectronic properties of these molecules were fine-tuned with the objective of attaining strong absorption at longer wavelengths by changing the low-ionization-potential moiety. The electron-accepting function of these materials was investigated with poly(3-n-hexylthiophene) (P3HT) as a standard electron donor. Significant photocurrent generation in the near infrared region, with an external quantum yield reaching as high as 22?% at 700?nm and an onset >800?nm was achieved. The results support efficient hole transfer to P3HT taking place after light absorption by the acceptor molecules. A Channel?II-dominated power conversion efficiency of up to 1.5?% was, thus, achieved.
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Disseminated nocardiosis in a patient with nephrotic syndrome following HIV infection.
Exp Ther Med
PUBLISHED: 08-06-2014
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In the present study, a case of disseminated abscesses caused by Nocardia in a patient undergoing immunosuppressive therapy for nephrotic syndrome and infected with human immunodeficiency virus (HIV) is described. To the best of our knowledge, this is the first such case to be reported. The patient had membranous nephropathy and received systemic corticosteroid therapy for one year. During this time, the patient was diagnosed with HIV and developed disseminated abscesses in the lungs, brain and hip. Pathogens isolated from sputum and pus were identified as Nocardia asteroides. The patient was successfully treated following surgical drainage of the abscesses and by oral administration of trimethoprim-sulfamethoxazole.
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Minimally invasive surgery treatment for the patients with spontaneous supratentorial intracerebral hemorrhage (MISTICH): protocol of a multi-center randomized controlled trial.
BMC Neurol
PUBLISHED: 08-05-2014
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The choice of surgical or conservative treatment for patients with spontaneous intracerebral hemorrhage is controversial. Some minimally invasive treatments have been applied to hematoma evacuation and could improve prognosis to some extent. Up to now, studies on minimally invasive surgery for patients with spontaneous intracerebral hemorrhage are still insufficient.
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Origin of yellow-band emission in epitaxially grown GaN nanowire arrays.
ACS Appl Mater Interfaces
PUBLISHED: 08-01-2014
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Here, we report the origin of the yellow-band emission in epitaxial GaN nanowire arrays grown under carbon-free conditions. GaN nanowires directly grown on [0001]-oriented sapphire substrate exhibit an obvious and broad yellow-band in the visible range 400-800 nm, whereas the insertion of Al/Au layers in GaN-sapphire interface significantly depresses the visible emission, and only a sharp peak in the UV range (369 nm) can be observed. The persuasive differences in cathodoluminescence provide direct evidence for demonstrating that the origin of the yellow-band emission in GaN nanowire arrays arises from dislocation threading. The idea using buffering/barrier layers to isolate the dislocation threading in epitaxially grown GaN nanowires can be extended to the rational synthesis and structural defect controlling of a wide range of semiconductor films and nanostructures with superior crystal quality and excellent luminescence property.
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[Microbubbles targeted to P-selectin for evaluating testicular ischemia-reperfusion injury in rabbits].
Zhonghua Nan Ke Xue
PUBLISHED: 07-18-2014
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To explore the feasibility of evaluating complete ischemia-reperfusion injury (IRI) of the testis by contrast-enhanced ultrasonography with microbubbles (MB) targeted to P-selectin (MBp) in rabbits.
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DNA-PKcs deficiency sensitizes the human hepatoma HepG2 cells to cisplatin and 5-fluorouracil through suppression of the PI3K/Akt/NF-?B pathway.
Mol. Cell. Biochem.
PUBLISHED: 07-11-2014
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The aim of the present study was to investigate the effects of DNA-PKcs deficiency on the chemosensitivity of human hepatoma HepG2 cells to cisplatin (CDDP) and 5-fluorouracil (5-Fu), and to explore the underlying molecular mechanism. After transfection with DNA-PKcs siRNA or control siRNA, HepG2 cells were exposed to combination treatment of CDDP and 5-Fu. The cell viability, DNA damage, cell apoptosis, intracellular reactive oxygen species and glutathione (GSH) level, expression of apoptosis related proteins, activity of phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) pathway, and nuclear factor-?B (NF-?B) pathways were assessed. The combination of CDDP and 5-Fu had a synergistic cytotoxic effect in HepG2 cells in terms of the cell viability, DNA damage, apoptosis, and oxidative stress level. DNA-PKcs siRNA could sensitize the HepG2 cells to the combined treatment. DNA-PKcs suppression further reduced the Akt phosphorylation level and Bcl-2 expression in HepG2 cells exposed to CDDP and 5-Fu, but enhanced the expression of pro-apoptotic proteins p53 and caspase-3. Moreover, CDDP could inhibit the transcriptional activity of NF-?B through degradation of IkB-?, while 5-Fu alone seemed in some extent increases the NF-?B activity. The combined treatment with CDDP and 5-Fu resulted in significantly decrease of the transcriptional activity of NF-?B, which was further aggravated by DNA-PKcs siRNA treatment. In conclusion, DNA-PKcs suppression had complementary effects in combination with CDDP and 5-Fu treatment in HepG2 cells, which was associated with suppression of NF-?B signaling pathway cascade, activation of caspase-3 and p53, as well as down-regulation of Bcl-2 and GSH.
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Prevalence and spectrum of Nkx2.6 mutations in patients with congenital heart disease.
Eur J Med Genet
PUBLISHED: 06-27-2014
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Congenital heart disease (CHD) is the most common form of birth defect and is the most prevalent non-infectious cause of infant death. A growing body of evidence documents that genetic defects are involved in the pathogenesis of CHD. However, CHD is a genetically heterogeneous disease and the genetic basis underpinning CHD in an overwhelming majority of patients remain unclear. In this study, the coding exons and flanking introns of the Nkx2.6 gene, which codes for a homeodomain-containing transcription factor important for normal cardiovascular development, were sequenced in 320 unrelated patients with CHD, and two novel heterozygous Nkx2.6 mutations, p.V176M and p.K177X, were identified in two unrelated patients with CHD, respectively, including a patient with tetralogy of Fallot and a patient with double outlet of right ventricle and ventricular septal defect. The mutations were absent in 400 control chromosomes and the altered amino acids were completely conserved evolutionarily across species. Due to unknown transcriptional targets of Nkx2.6, the functional consequences of the identified mutations at transcriptional activity were evaluated by using Nkx2.5 as a surrogate. Alignment between human Nkx2.6 and Nkx2.5 proteins showed that V176M-mutant Nkx2.6 was equivalent to V182M-mutant Nkx2.5 and K177X-mutant Nkx2.6 was equal to K183X-mutant Nkx2.5, and introduction of V182M or K183X into Nkx2.5 significantly diminished its transcriptional activating function when compared with its wild-type counterpart. To our knowledge, this is the first report on the association of Nkx2.6 loss-of-function mutation with increased susceptibility to tetralogy of Fallot or double outlet of right ventricle and ventricular septal defect, providing novel insight into the molecular mechanism of CHD.
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[The effect of the structure of epithelial root sheath on the development of tooth root].
Shanghai Kou Qiang Yi Xue
PUBLISHED: 06-18-2014
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To investigate the effect of the structure of epithelial root sheath (ERS) on the development of tooth root.
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The efficacy and safety of bevacizumab combined with chemotherapy in treatment of HER2-negative metastatic breast cancer: a meta-analysis based on published phase III trials.
Tumour Biol.
PUBLISHED: 06-16-2014
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Bevacizumab (Bev) combined with chemotherapy significantly improves progression-free survival (PFS) but not overall survival (OS) in patients with human epidermal growth factor receptor 2 (HER2)-negative metastatic breast cancer (MBC). The efficacy and safety depend on the type of chemotherapy combined with Bev. We performed a meta-analysis of phase III trials to evaluate the efficacy and safety of Bev + standard chemotherapy for HER2-negative MBC. The Cochrane Central Register of Controlled Trials, the Cochrane databases, EMBASE, MEDLINE, and ClinicalTrials.gov were analyzed. The primary outcomes included PFS, OS, and toxicity. Event-based hazard ratios (HRs) and relative risks (RRs) were expressed with the 95 % confidence intervals (CIs). Four randomized controlled trials consisting of 3082 patients were included. Bev + standard chemotherapy improved PFS (HR 0.70, CI 0.64-0.77, P?=?0.000) but had no effect on OS (HR 0.92, CI 0.82-1.02, P?=?0.119). Bev + chemotherapy increased the incidence of febrile neutropenia (RR 1.45, CI 1.00 to 2.09, P?=?0.048), proteinuria (RR 11.68, CI 3.72-36.70, P?=?0.000), sensory neuropathy (RR 1.33, CI 1.05-1.70, P?=?0.020), and grade ?3 hypertension (RR 13.94, CI 7.06-27.55, P?=?0.000). No differences in efficacy were observed between Bev + paclitaxel and Bev + capecitabine (Cape), but Bev + Cape increased the incidence of neutropenia. Bev + standard chemotherapy improved PFS in HER2-negative MBC patients. No benefit in OS was observed. Bev + Cape and Bev + paclitaxel had similar treatment efficacy, but Bev + Cape had a higher incidence of neutropenia.
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Novel chitosan-based pH-sensitive and disintegrable polyelectrolyte nanogels.
Colloids Surf B Biointerfaces
PUBLISHED: 05-16-2014
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A novel approach to design pH-sensitive and disintegrable polyelectrolyte nanogels composed of citraconic-based N-(carboxyacyl) chitosan (polyanion) and quaternary chitosan (polycation) was reported. Firstly, the hydrolysis of citraconic-modified chitosan was monitored using fluorescamine assay and it could selectively dissociate in acidic media (e.g., pH ?5.0) due to the isomerization during the addition of citraconic anhydride to chitosan. Secondly, the self-assembly behaviors of different polyelectrolyte pairs between citraconic-based chitosan and quaternary chitosan were investigated via colloidal titration assay. It was indicated that the difference in molecular weight (MW) of opposite charged polyelectrolytes played an important role on the formation of polyelectrolyte nanogels. Results showed that polyelectrolyte nanogels (ca. 300nm in size) only formed when polyanion and polycation had a very large difference in MW. The pH-sensitive behavior of polyelectrolyte nanogels was comprehensively investigated by dynamic light scattering (DLS) and transmission electron microscope (TEM). The incorporation of charge-conversional citraconic-based chitosan into polyelectrolyte complexes has provided an effective approach to prepare polyelectrolyte nanogels which were very stable at neutral pH but disintegrated quickly in acidic media.
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The CCCH zinc finger protein gene AtZFP1 improves salt resistance in Arabidopsis thaliana.
Plant Mol. Biol.
PUBLISHED: 05-08-2014
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The CCCH type zinc finger proteins are a super family involved in many aspects of plant growth and development. In this study, we investigated the response of one CCCH type zinc finger protein AtZFP1 (At2g25900) to salt stress in Arabidopsis. The expression of AtZFP1 was upregulated by salt stress. Compared to transgenic strains, the germination rate, emerging rate of cotyledons and root length of wild plants were significantly lower under NaCl treatments, while the inhibitory effect was significantly severe in T-DNA insertion mutant strains. At germination stage, it was mainly osmotic stress when treated with NaCl. Relative to wild plants, overexpression strains maintained a higher K(+), K(+)/Na(+), chlorophyll and proline content, and lower Na(+) and MDA content. Quantitative real-time PCR analysis revealed that the expression of stress related marker genes KIN1, RD29B and RD22 increased more significantly in transgenic strains by salt stress. Overexpression of AtZFP1 also enhanced oxidative and osmotic stress tolerance which was determined by measuring the expression of a set of antioxidant genes, osmotic stress genes and ion transport protein genes such as SOS1, AtP5CS1 and AtGSTU5. Overall, our results suggest that overexpression of AtZFP1 enhanced salt tolerance by maintaining ionic balance and limiting oxidative and osmotic stress.
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Reporter-triggered isothermal exponential amplification strategy in ultrasensitive homogeneous label-free electrochemical nucleic acid biosensing.
Chem. Commun. (Camb.)
PUBLISHED: 04-30-2014
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A simple and novel reporter-triggered isothermal exponential amplification reaction (R-EXPAR) integrated with a miniaturized electrochemical device was developed, which achieved excellent improvement (five orders of magnitude) of sensitivity toward reporter, G-quadruplex. This R-EXPAR strategy has been successfully implemented to construct a homogeneous label-free electrochemical sensor for ultrasensitive DNA detection.
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Inhibition of Campylobacter jejuni on fresh chicken breasts by ?-carrageenan/chitosan-based coatings containing allyl isothiocyanate or deodorized oriental mustard extract.
Int. J. Food Microbiol.
PUBLISHED: 04-22-2014
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Campylobacter species are common bacterial pathogens associated with human gastroenteritis worldwide. The objectives of this study were to determine the minimum inhibitory (MIC) and minimum bactericidal (MBC) concentrations of allyl isothiocyanate (AITC) against 4 Campylobacter jejuni strains in Mueller-Hinton (MH) broth at 4, 21, 37 and 42°C and to screen the C. jejuni strains for their ability to degrade sinigrin (which forms AITC) in pH7.0 MH broth at 35°C for 21d. Also evaluated was the antimicrobial activity of an edible 0.2% ?-carrageenan/2% chitosan-based coating containing AITC or deodorized oriental mustard extract against a 4 strain C. jejuni cocktail (6.2log10CFU/g) on vacuum-packaged fresh chicken breasts during 4°C storage. MIC values of AITC were 0.63 to 1.25ppm and 2.5 to 5ppm against tested strains at 37 and 42°C, respectively. However, the MBC was 2.5 and 5ppm at 37 and 42°C, respectively, and increased to a range of 40 to 160ppm at 4°C. ?-Carrageenan/chitosan-based coatings containing 50 or 100?l/g AITC reduced viable C. jejuni to undetectable levels on chicken breast after 5d at 4°C, while 25?l/g AITC or 200 to 300mg/g mustard extract in coatings reduced C. jejuni numbers by 1.75 to 2.78log10CFU/g more than control coatings without antimicrobial. Both oriental mustard extract (50 to 300mg/g) and AITC (?25?l/g) reduced aerobic bacteria by 1.72 to 2.75log10CFU/g and lactic acid bacteria (LAB) by 0.94 to 3.36log10CFU/g by 21d compared to the control coating. ?-Carrageenan/chitosan coatings containing ?50?l/g AITC or ?300mg/g oriental mustard showed excellent potential to control C. jejuni viability on raw chicken.
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IRE1? is essential for Xenopus pancreas development.
J Biomed Res
PUBLISHED: 04-01-2014
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Inositol requiring enzyme-1 (IRE1) is highly conserved from yeasts to humans. Upon the endoplasmic reticulum (ER) stress, IRE1 activates X-box-binding protein 1 (XBP1) by unconventionally splicing XBP1 mRNA, which activates the unfolded protein response (UPR) to restore ER homeostasis. In mice, IRE1? inactivity leads to embryonic death and IRE1? plays an essential role in extraembryonic tissues and the placenta. However, its precise action in the embryo proper is still unknown. In this study, the loss of function analysis was performed to investigate the function of Xenopus IRE1? (xIRE1?) during pancreas development. Firstly, the complete open reading frame of xIRE1? was amplified and the expression pattern was detected. The effects of Xenopus IRE1? and XBP1 during embryo development were detected with whole-mount in situ hybridization. The results demonstrated that xIRE1? was much closer to human IRE1? when compared with their sequence alignment. xIRE1? was expressed strongly in developing pancreas and the knockdown of xIRE1? inhibited the differentiation and specification of the pancreas. xIRE1?, which was required for cytoplasmic splicing of XBP1 pre-mRNA and XBP1MO, also showed inhibitory effects on pancreas development. These results suggest that xIRE1? is essential for pancreas development during embryogenesis and functions via the XBP1 dependent pathway.
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A novel method for the determination of the degree of deacetylation of chitosan by coulometric titration.
Int. J. Biol. Macromol.
PUBLISHED: 03-28-2014
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A novel method to determine the degree of deacetylation of chitosan is described. In this method, the coulometric titrant OH- is generated by the electrolysis of water. The OH- reacted with the residual hydrochloric acid in chitosan solution and the degree of deacetylation was obtained by Faraday's law. The optimized experimental parameters in this study were 1.0 mol/L KCl as supporting electrolyte, 15.00 mA as the intensity of constant current, composite glass electrode as indicating electrode couples, double platinum generated electrode-platinum wire auxiliary electrode as working electrode pairs, pH 3.80 as the titration end-point. The degree of deacetylation in the four samples, which varied from 70 to 95% were measured. The results were similar to those from 1H NMR and the standard deviations were lower than 0.5%. With merit of simplicity, convenience, quickness, high accuracy and precision, automatic detection of titration end-point and low-cost, the proposed method will be very useful in the industrial production.
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Intraperitoneal administration of the globular adiponectin gene ameliorates diabetic nephropathy in Wistar rats.
Mol Med Rep
PUBLISHED: 03-12-2014
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The present study investigated the potential effects of the long-term expression of exogenous adiponectin (ADPN) on normal and diabetic kidneys. Type 2 diabetes mellitus models were induced by high-lipid and high-sucrose feeding plus intraperitoneal injection of streptozotocin. The recombinant plasmid pIRES2-EGFP-gAd, which is able to co-express globular ADPN (gAd) and enhanced green fluorescent protein (EGFP), was intraperitoneally injected into rat models mediated by Lipofectamine. In total, 32 Wistar rats were randomly assigned into four groups: the normal control group, the diabetes group, the diabetes group treated with pIRES2-EGFP-gAd and the diabetes group treated with pIRES2-EGFP. After 12 weeks, serum biochemistry and urine albumin levels were measured. The kidneys were collected to assess the generation of reactive oxygen species (ROS) and the renal pathological changes were observed by light microcopy. The protein expression of endothelial nitric oxide synthase (eNOS), transforming growth factor-?1 (TGF-?1) and phosphorylated adenosine monophosphate-activated protein kinase (p-AMPK) were determined by an immunohistochemical staining method and western blot analysis. Intraperitoneal injection of the human gAd gene via Lipofectamine resulted in abundant ADPN protein in the kidney. In the diabetic rats, the delivery of the exogenous gAd gene ameliorated the progression of diabetic nephropathy (DN). ADPN attenuated urine albumin excretion in the diabetic rats. ADPN also mitigated glomerular mesangial expansion, reduced the generation of ROS and prevented interstitial fibrosis. In addition, the expression of gAd inhibited the renal expression of TGF-?1, promoted the protein expression of eNOS and activated the opening of the AMPK signaling pathway in the renal tissues of the diabetic rats. Despite the effects of ADPN on DN being controversial, these observations indicate that the supplementation of ADPN is beneficial in ameliorating DN in rats.
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GATA5 loss-of-function mutations associated with congenital bicuspid aortic valve.
Int. J. Mol. Med.
PUBLISHED: 03-11-2014
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Bicuspid aortic valve (BAV) is the most common form of congenital cardiovascular defect in humans worldwide and is responsible for substantial morbidity and mortality. Accumulating evidence has demonstated that genetic risk factors are involved in the pathogenesis of BAV. However, BAV is genetically heterogeneous and the genetic basis underlying BAV in a large number of patients remains unknown. In the present study, the coding regions and splice junction sites of the GATA5 gene, which codes for a zinc-finger transcription factor crucial for the normal development of the aortic valve, was sequenced initially in 110 unrelated patients with BAV. The available relatives of the mutation carriers and 200 unrelated healthy individuals used as controls were subsequently genotyped for GATA5. The functional effect of the mutations was characterized by using a luciferase reporter assay system. As a result, two novel heterozygous GATA5 mutations, p.Y16D and p.T252P, were identified in two families with autosomal dominant inheritance of BAV, respectively. The variations were absent in 400 control chromosomes and the altered amino acids were completely conserved evolutionarily. Functional assays revealed that the two GATA5 mutants were associated with significantly reduced transcriptional activity compared with their wild-type counterpart. To the best of our knowledge, this is the first study on the association of GATA5 loss-of-function mutations with enhanced susceptibility to BAV, providing novel insight into the molecular mechanism involved in human BAV and suggesting a potential role for the early prophylaxis and personalized treatment of this common congenital heart disease.
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Effect of Maillard reaction products on the physical and antimicrobial properties of edible films based on ?-polylysine and chitosan.
J. Sci. Food Agric.
PUBLISHED: 02-24-2014
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Edible films based on Maillard reaction products (MRPs) of ?-polylysine and chitosan, without the use of any plasticiser, were prepared by solution casting. The effect of Maillard reaction parameters (reaction time and the ratio of polylysine/chitosan) of ?-polylysine and chitosan on the structure, moisture content, water solubility, total colour difference and mechanical properties of edible films formed by MRPs were systematically evaluated.
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Cervical squamous cell carcinoma with isolated tibial metastasis: A case report and review of the literature.
Oncol Lett
PUBLISHED: 02-22-2014
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Bone metastasis resulting from carcinoma of the cervix is rare, particularly in the isolated distal appendicular bone. A 43-year-old female was diagnosed with a right tibial tumor with progressive right knee pain for three months, which was diagnosed as poorly differentiated metastatic squamous cell carcinoma, and further confirmed by biopsy of the proximal tibia. The patient was diagnosed with cervical squamous cell carcinoma with tibial metastasis following further examination, despite a lack of gynecological symptoms. In contrast to the poor outcome commonly observed in patients with bone metastasis, the patient survived and remained disease-free 41 months after surgical excision of the metastatic tumor and radical hysterectomy followed by chemoradiotherapy. The present case is one of the few documented cases of metastasis to the tibia arising from carcinoma of the uterine cervix and may be the first regarding isolated metastasis at this site.
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Sinomenine inhibits microglia activation and attenuates brain injury in intracerebral hemorrhage.
Mol. Immunol.
PUBLISHED: 02-10-2014
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Intracerebral hemorrhage (ICH) causes morbidity and mortality and commonly follows the reperfusion after an ischemic event. Microglial activation mediated cytokine and protease secretion contributes to brain injury in ICH. Previous studies have shown that sinomenine possesses potent immunoregulatory properties. However, little is known about its exact role in ICH. In the present study, to investigate the effect of sinomenine on microglial cells inflammation, we treated ICH-challenged BV2 microglial cells with sinomenine in vitro, and explored its neuroprotection role in intracerebral hemorrhage in vivo. Changes in inflammatory cytokines, such as TNF-?, IL-1? and IL-6, reactive oxygen species (ROS) and NF-?B activation NF-?B were observed. In addition, the neurological deficit and cerebral water content of ICH mice were studied. The results demonstrated that sinomenine could inhibit the release of these cytokines and attenuate ROS production in a dose-dependent manner, and reduce NF-?B activation. Furthermore, sinomenine markedly inhibited cerebral water content and neurological deficit. In conclusion, our findings suggest that sinomenine played the protective effects through inhibition of microglial inflammation, and the findings also provided a novel therapy to treat ICH induced brain injury.
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Structure and antimicrobial mechanism of ?-polylysine-chitosan conjugates through Maillard reaction.
Int. J. Biol. Macromol.
PUBLISHED: 02-09-2014
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The aim of the study was to testify the formation and antimicrobial activity of ?-polylysine-chitosan conjugate through Maillard reaction. The results of UV absorbance, browning index and fluorescence changes of Maillard reaction products (MRPs) between ?-polylysine and chitosan indicated there existed Maillard reaction between ?-polylysine and chitosan and the formation of their conjugate. The conjugate showed strong antibacterial activity against Escherichia coli, Staphylococcus aureus, Bacillus subtilis and beer yeast. Morphologies of E. coli and S. aureus treated with the conjugate were observed by transmission electron microscopy (TEM). The results revealed that the conjugate of ?-polylysine and chitosan increased the permeability of the outer membrane (OM) and inner membrane (IM) and ultimately disrupted bacterial cell membranes, with the release of cellular cytoplasm.
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Association of genetic polymorphisms in HSD17B1, HSD17B2 and SHBG genes with hepatocellular carcinoma risk.
Pathol. Oncol. Res.
PUBLISHED: 02-06-2014
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Genetic polymorphisms of enzymes involved in estrogen synthesizing/transporting can influence the risk of hormone-dependent diseases. The incidence rate and relative risk for hepatocellular carcinoma (HCC) are higher in men than in women. This study was conducted to explore the relationship of single nucleotide polymorphisms (SNPs) in 17 ?-Hydroxysteroid dehydrogenases (HSD17B1 and HSD17B2) and sex hormone-binding globulin (SHBG) genes with the risk of HCC within Chinese Han population. Polymorphisms of HSD17B1 rs676387, HSD17B2 rs8191246 and SHBG rs6259 were genotyped in 253 HCC patients and 438 healthy control subjects using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Significantly increased HCC risk was found to be associated with T allele of rs676387 and G allele of rs8191246. Increased HCC risks were found in different genetic model (TT genotype in a recessive model, T allele carriers in a dominant model, TT genotype and TG genotype in a codominant model for HSD17B1 rs676387, G allele carriers in a dominant model and AG genotype in a codominant model for HSD17B2 rs8191246, respectively). No association between SHBG rs6259 and HCC risk was observed. The present study provided evidence that HSD17B1 rs676387 and HSD17B2 rs8191246 were association with HCC development. Further studies in diverse ethnic population with larger sample size were recommended to confirm the findings.
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A novel copigment of quercetagetin for stabilization of grape skin anthocyanins.
Food Chem
PUBLISHED: 02-02-2014
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The thermal and light stability of grape skin anthocyanins combined with quercetagetin was investigated at designed pH values of 3, 4 and 5. The molar ratios of anthocyanins to quercetagetin were 1:10, 1:20 and 1:40 for thermally treatment at 70 °C, 80 °C and 90 °C, respectively, and the ratios were tested at 5:1, 1:1, 1:5 and 1:10 in the light exposure experiments. The degradation reaction of anthocyanins in the presence of quercetagetin followed the first-order kinetic model. The half-life (t?/?) of anthocyanins was extended significantly with the increase of quercetagetin concentration (p<0.05). The total colour difference values (?E(?)) for the anthocyanin solutions with quercetagetin were smaller than those without copigment under the same experimental conditions (pH and light exposure time). Compared with epigallocatechin gallate (EGCG), tea polyphenols (TP), myricitrin and rutin, quercetagetin was the most effective copigment to stabilize grape skin anthocyanins.
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[Real-time ultrasound guided placement of permanent internal jugular vein catheters in maintenance hemodialysis patients].
Zhong Nan Da Xue Xue Bao Yi Xue Ban
PUBLISHED: 01-30-2014
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To investigate the value of real-time ultrasound guided placement of permanent internal jugular vein (IJV) catheterization in maintenance hemodialysis patients, and analyze its technical success and complication rate.
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Involvement of p38 MAPK in reactive astrogliosis induced by ischemic stroke.
Brain Res.
PUBLISHED: 01-13-2014
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Reactive astrogliosis is an essential feature of astrocytic response to all forms of central nervous system (CNS) injury and disease, which may benefit or harm surrounding neural and non-neural cells. Despite extensive study, its molecular triggers remain largely unknown in term of ischemic stroke. In the current study we investigated the role p38 mitogen-activated protein kinase (MAPK) in astrogliosis both in vitro and in vivo. In a mouse model of middle cerebral artery occlusion (MCAO), p38 MAPK activation was observed in the glia scar area, along with increased glial fibrillary acidic protein (GFAP) expression. In primary astrocyte cultures, hypoxia and scratch injury-induced astrogliosis was attenuated by both p38 inhibition and knockout of p38 MAPK. In addition, both knockout and inhibition of p38 MAPK also reduced astrocyte migration, but did not affect astrocyte proliferation. In a mouse model of permanent MCAO, no significant difference in motor function recovery and lesion volume was observed between conditional GFAP/p38 MAPK knockout mice and littermates. While a significant reduction of astrogliosis was observed in the GFAP/p38 knockout mice compared with the littermates. Our findings suggest that p38 MAPK signaling pathway plays an important role in the ischemic stroke-induced astrogliosis and thus may serve as a novel target to control glial scar formation.
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Prevalence and spectrum of GATA4 mutations associated with sporadic dilated cardiomyopathy.
Gene
PUBLISHED: 01-12-2014
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Dilated cardiomyopathy (DCM) is the most frequent type of primary myocardial disorder responsible for substantial morbidity and mortality. DCM is the third most common cause of heart failure and the most common reason for heart transplantation. A recent study has implicated GATA4 mutation in the pathogenesis of familial DCM. However, the prevalence and spectrum of GATA4 mutations associated with sporadic DCM remain unclear. In this study, the coding exons and exon-intron boundaries of the GATA4 gene, which encodes a cardiac transcription factor crucial for normal cardiogenesis, were sequenced in 220 unrelated patients with sporadic DCM. A total of 200 unrelated ethnically-matched healthy individuals used as controls were genotyped. The functional characteristics of the mutant GATA4 were assayed in contrast to its wild-type counterpart using a luciferase reporter assay system. As a result, 3 novel heterozygous GATA4 mutations, p.V39L, p.P226Q and p.T279S, were identified in 3 unrelated patients with sporadic DCM, with a mutational prevalence of approximately 1.36%. The missense mutations were absent in 400 control chromosomes and the altered amino acids were completely conserved evolutionarily across species. Functional analysis showed that the GATA4 mutants were consistently associated with significantly decreased transcriptional activity and markedly reduced the synergistic activation between GATA4 and NKX2-5. This study firstly links GATA4 mutations to increased susceptibility to sporadic DCM and provides novel insight into the molecular etiology underlying DCM, suggesting the potential implications for the early prophylaxis and allele-specific treatment of this common form of cardiomyopathy.
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Influence of whey protein-beet pectin conjugate on the properties and digestibility of ?-carotene emulsion during in vitro digestion.
Food Chem
PUBLISHED: 01-07-2014
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The impact of a whey protein isolate (WPI)-beet pectin (BP) conjugate (formed by dry-heating) on the physical properties and digestibilities of ?-carotene and carrier oil in oil-in-water emulsions was studied when they passed through a model gastrointestinal system. ?-Carotene emulsions were stabilized by WPI, unconjugated and conjugated WPI-BP, separately. The emulsions were then passed through an in vitro digestion model and the mean droplet size, droplet distribution, zeta-potential, free fatty acids and ?-carotene released were measured. The stability to droplet flocculation and coalescence during digestion was increased for the WPI-BP conjugate stabilized emulsion. Addition of BP onto the WPI stabilized emulsions could inhibit the releases of carrier oil (MCT) and ?-carotene. The releases of free fatty acids and ?-carotene did not differ greatly between the unconjugated and conjugated WPI-BP stabilized emulsions. These results have important implications for protein-polysaccharide stabilized emulsions and conjugates used for the protection and delivery of bioactive compounds.
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Methylene blue promotes quiescence of rat neural progenitor cells.
Front Cell Neurosci
PUBLISHED: 01-01-2014
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Neural stem cell-based treatment holds a new therapeutic opportunity for neurodegenerative disorders. Here, we investigated the effect of methylene blue on proliferation and differentiation of rat neural progenitor cells (NPCs) both in vitro and in vivo. We found that methylene blue inhibited proliferation and promoted quiescence of NPCs in vitro without affecting committed neuronal differentiation. Consistently, intracerebroventricular infusion of methylene blue significantly inhibited NPC proliferation at the subventricular zone (SVZ). Methylene blue inhibited mTOR signaling along with down-regulation of cyclins in NPCs in vitro and in vivo. In summary, our study indicates that methylene blue may delay NPC senescence through enhancing NPCs quiescence.
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Total ionizing dose (TID) effects of ? ray radiation on switching behaviors of Ag/AlO x /Pt RRAM device.
Nanoscale Res Lett
PUBLISHED: 01-01-2014
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The total ionizing dose (TID) effects of (60)Co ? ray radiation on the resistive random access memory (RRAM) devices with the structure of Ag/AlO x /Pt were studied. The resistance in low resistance state (LRS), set voltage, and reset voltage are almost immune to radiation, whereas the initial resistance, resistance at high resistance state (HRS), and forming voltage were significantly impacted after radiation due to the radiation-induced holes. A novel hybrid filament model is proposed to explain the radiation effects, presuming that holes are co-operated with Ag ions to build filaments. In addition, the thermal coefficients of the resistivity in LRS can support this hybrid filament model. The Ag/AlO x /Pt RRAM devices exhibit radiation immunity to a TID up to 1 Mrad(Si) and are highly suitable for radiation-hard electronics applications.
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Zinc dependent endopeptidases of matrix metalloproteinases-9 expressions is associated with tumor metastases of oral squamous cell carcinoma in Chinese population: a meta-analysis.
Int J Clin Exp Med
PUBLISHED: 01-01-2014
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Matrix metalloproteinase-9 (MMP-9) is an important member of zinc dependent endopeptidases family and is considered to be involved in the invasion and metastasis of cancer cells. Many studies were published to assess the prognostic role of MMP-9 expression in patients with oral squamous cell Carcinoma, but the findings from those studies were inconsistent in Chinese population. We searched eligible studies in Pubmed, Embase, and Web of Science databases. Six studies with a total of 556 patients were finally included into the meta-analysis. The pooled odds ratios (OR) with the corresponding 95% confidence interval (95% CIs) for positive rate of MMP-9 were calculated by using meta-analysis. Overall, MMP-9 positive expression was associated with tumor metastases in patients with oral squamous cell Carcinoma (fixed-effects OR 4.24, 95% CI 2.25-7.99, P < 0.001; random-effects OR 4.35, 95% CI 2.31-8.21, P < 0.001). Our results indicated that MMP-9 expression is associated with tumor metastases in patients with oral squamous cell carcinoma, and patients with higher MMP-9 expression have less tumor metastases.
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Evaluation of Canine Bone Marrow-derived Mesenchymal Stem Cells After Long-term Cryopreservation.
Zool. Sci.
PUBLISHED: 12-11-2013
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Autologous bone marrow-derived mesenchymal stem cell (BMSCs)-based therapies show great potential in regenerative medicine. However, long-term storage and preservation of BMSCs for clinical use is still a great clinical challenge. The present study aimed to analyze the effect of long-term cryopreservation on the regenerative ability of BMSCs. After cryopreservation of BMSCs from beagle dogs for three years, cell viability, and quantitative analysis of alkaline phosphatase (ALP) activity, surface adherence, and mineralized nodule formation were analyzed. BMSCs in cell-scaffold complex were then implanted into nude mice. There was no significant difference in cell viability and ALP activity between osteogenic differentiation and non-osteogenic differentiation of BMSCs, and BMSCs in cell-scaffold complex retained osteogenic differentiation ability in vivo. These results indicate that long-term cryopreserved BMSCs maintain their have capacity to contribute to regeneration.
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[Research advance of large conductance Ca(2+)-activated K+ channels in cardiovascular system].
Sheng Li Ke Xue Jin Zhan
PUBLISHED: 11-16-2013
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The large conductance Ca(2+)-activated potassium channels (BK(Ca) channels), an important class of ion channels in cell membrane, are widely expressed in each part of the body including cardiovascular system, and play an important role in regulating cardiovascular activity. This review introduces the recent progress on the structural features, function, and modulation of BK(Ca) channels in cardiovascular system briefly.
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Synthesis, Microstructure, and Cathodoluminescence of [0001]-Oriented GaN Nanorods Grown on Conductive Graphite Substrate.
ACS Appl Mater Interfaces
PUBLISHED: 11-11-2013
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One-dimensional GaN nanorods with corrugated morphology have been synthesized on graphite substrate without the assistance of any metal catalyst through a feasible thermal evaporation process. The morphologies and microstructures of GaN nanorods were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM). The results from HRTEM analysis indicate that the GaN nanorods are well-crystallized and exhibit a preferential orientation along the [0001] direction with Ga(3+)-terminated (101?1) and N(3-)-terminated (101?1?) as side facets, finally leading to the corrugated morphology surface. The stabilization of the electrostatic surface energy of {101?1} polar surface in a wurtzite-type hexagonal structure plays a key role in the formation of GaN nanorods with corrugated morphology. Room-temperature cathodoluminescence (CL) measurements show a near-band-edge emission (NBE) in the ultraviolet range and a broad deep level emission (DLE) in the visible range. The crystallography and the optical emissions of GaN nanorods are discussed.
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[Circular dichroism chromatography of secondary structures of anti-HBV IgY in eggs from hens immunized with recombinant yeast HBV vaccine].
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi
PUBLISHED: 11-09-2013
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To study the generation and structure of anti-HBV IgY in eggs from hens immunized with recombinant yeast HBV vaccine.
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Photodegradation of parabens by Fe(III)-citrate complexes at circumneutral pH: Matrix effect and reaction mechanism.
Sci. Total Environ.
PUBLISHED: 09-26-2013
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The photodegradation of four parabens including methyl-, ethyl-, propyl-, and butyl-paraben in the presence of Fe(III)-citrate complexes under simulated sunlight was investigated. The degradation of parabens increased with decreasing pH within the range of 5.0-8.0 at the Fe(III)-to-citrate ratio of 10:150 (?M). The addition of low-molecular-weight carboxylic acids showed different effects on the photodegradation of methylparaben. The low-photoreactive carboxylic acids inhibited the photodegradation of methylparaben in the order of formic acid>succinic acid>acetic acid>malonic acid. In contrast, oxalic acid enhanced the photodegradation and exhibited appreciable synergistic effect with Fe(III)-citrate at concentration higher than 500?M. Up to 99.0% of substrate was degraded after 30min at pH6.0 in the Fe(III)-citrate-oxalate system. The various fractions of fulvic acid inhibited the photodegradation of methylparaben. The inhibition increased with increasing nominal molecular weight of fractionated fulvic acid. Moreover, the photodegradation of methylparaben was inhibited in natural waters in the order of Liangzi Lake
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Macromolecular prodrug of dexamethasone prevents particle-induced peri-implant osteolysis with reduced systemic side effects.
J Control Release
PUBLISHED: 09-19-2013
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Aseptic implant loosening related to implant wear particle-induced inflammation is the most common cause of failure after joint replacement. Modulation of the inflammatory reaction to the wear products represents a rational approach for preventing aseptic implant failure. Long-term treatment using anti-inflammatory agents, however, can be associated with significant systemic side effects due to the drugs lack of tissue specificity. To address this issue, N-(2-hydroxypropyl) methacrylamide (HPMA) copolymer-dexamethasone conjugate (P-Dex) was developed and evaluated for prevention of wear particle-induced osteolysis and the loss of fixation in a murine prosthesis failure model. Daily administration of free dexamethasone (Dex) was able to prevent wear particle-induced osteolysis, as assessed by micro-CT and histological analysis. Remarkably, monthly P-Dex administration (dose equivalent to free Dex treatment) was equally effective as free dexamethasone, but was not associated with systemic bone loss (a major adverse side effect of glucocorticoids). The reduced systemic toxicity of P-Dex is related to preferential targeting of the sites of wear particle-induced inflammation and its subcellular sequestration and retention by local inflammatory cell populations, resulting in sustained therapeutic action. These results demonstrate the feasibility of utilizing a macromolecular prodrug with reduced systemic toxicity to prevent wear particle-induced osteolysis.
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GATA4 loss-of-function mutation underlies familial dilated cardiomyopathy.
Biochem. Biophys. Res. Commun.
PUBLISHED: 09-01-2013
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The cardiac transcription factor GATA4 is essential for cardiac development, and mutations in this gene have been implicated in a wide variety of congenital heart diseases in both animal models and humans. However, whether mutated GATA4 predisposes to dilated cardiomyopathy (DCM) remains unknown. In this study, the whole coding region and splice junction sites of the GATA4 gene was sequenced in 110 unrelated patients with idiopathic DCM. The available relatives of the index patient harboring an identified mutation and 200 unrelated ethnically matched healthy individuals used as controls were genotyped. The functional effect of the mutant GATA4 was characterized in contrast to its wild-type counterpart using a luciferase reporter assay system. As a result, a novel heterozygous GATA4 mutation, p.C271S, was identified in a family with DCM inherited as an autosomal dominant trait, which co-segregated with DCM in the family with complete penetrance. The missense mutation was absent in 400 control chromosomes and the altered amino acid was completely conserved evolutionarily among species. Functional analysis demonstrated that the GATA4 mutant was associated with significantly decreased transcriptional activity and remarkably reduced synergistic activation between GATA4 and NKX2-5, another transcription factor crucial for cardiogenesis. The findings provide novel insight into the molecular mechanisms involved in the pathogenesis of DCM, suggesting the potential implications in the prenatal diagnosis and gene-specific treatment for this common form of myocardial disorder.
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Deciphering the role of Burkholderia cenocepacia membrane proteins in antimicrobial properties of chitosan.
Arch. Microbiol.
PUBLISHED: 08-26-2013
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Chitosan, a versatile derivative of chitin, is widely used as an antimicrobial agent either alone or mixed with other natural polymers. Burkholderia cenocepacia is a multidrug-resistant bacteria and difficult to eradicate. Our previous studies shown that chitosan had strong antibacterial activity against B. cenocepacia. In the current study, we have investigated the molecular aspects for the susceptibility of B. cenocepacia in response to chitosan antibacterial activity. We have conducted RNA expression analysis of drug efflux system by RT-PCR, membrane protein profiling by SDS-PAGE, and by LC-MS/MS analysis following the validation of selected membrane proteins by real-time PCR analysis. By RT-PCR analysis, it was found that orf3, orf9, and orf13 were expressed at detectable levels, which were similar to control, while rest of the orf did not express. Moreover, shotgun proteomics analysis revealed 21 proteins in chitosan-treated cells and 16 proteins in control. Among them 4 proteins were detected as shared proteins under control and chitosan-treated cells and 17 proteins as uniquely identified proteins under chitosan-treated cells. Among the catalog of uniquely identified proteins, there were proteins involved in electron transport chain and ATP synthase, metabolism of carbohydrates and adaptation to atypical conditions proteins which indicate that utilization and pattern of chitosan is diverse which might be responsible for its antibacterial effects on bacteria. Moreover, our results showed that RND drug efflux system, which display the ability to transport a variety of structurally unrelated drugs from a cell and consequently are capable of conferring resistance to a diverse range of chemotherapeutic agents, was not determined to play its role in response to chitosan. It might be lipopolysaccharides interaction with chitosan resulted in the destabilization of membrane protein to membrane lyses to cell death. Membrane proteome analysis were also validated by RT-qPCR analysis, which corroborated our results that of membrane proteins.
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The fate of sulfur during rapid pyrolysis of scrap tires.
Chemosphere
PUBLISHED: 07-28-2013
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The fate of sulfur during rapid pyrolysis of scrap tires at temperatures from 673 to 1073K was investigated. Sulfur was predominant in the forms of thiophenic and inorganic sulfides in raw scrap tires. In the pyrolysis process, sulfur in organic forms was unstable and decomposed, leading to the sulfur release into tar and gases. At 673 and 773K, a considerable amount of sulfur was distributed in tar. Temperature increasing from 773 to 973K promoted tar decomposition and facilitated sulfur release into gases. At 1073K, the interactions between volatiles and char stimulated the formation of high-molecular-weight sulfur-containing compounds. After pyrolysis, almost half of the total content of sulfur in raw scrap tires still remained in the char and was mostly in the form of sulfides. Moreover, at temperatures higher than 873K, part of sulfur in the char was immobilized in the sulfates. In the pyrolysis gases, H2S was the main sulfur-containing gas. Increasing temperature stimulated the decomposition of organic polymers in scrap tires and more H2S was formed. Besides H2S, other sulfur-containing gases such as CH3SH, COS and SO2 were produced during the rapid pyrolysis of scrap tires.
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Triangular ZnO nanosheets: synthesis, crystallography and cathodoluminescence.
J Nanosci Nanotechnol
PUBLISHED: 07-26-2013
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ZnO nanosheets with triangular morphology have been synthesized on an Au-coated silicon substrate through a facile thermal evaporation process. The morphologies and microstructures of the nanosheets were studied by a scanning electron microscope (SEM) and a high-resolution transmission electron microscope (HR-TEM). These studies show that a nanosheet is commonly composed of two parts: a triangular ZnO sheet and an Au nanoparticle attached on its tip-end. Detailed crystallography analyses conclude that the formation of the highly crystalline nanostructures can be assigned to a combination of a vapor-liquid-solid (VLS) process that is believed to be responsible for its initial nucleation and subsequent crystallization along the growth direction, and a vapor-solid (VS) process that is responsible for its further radial growth. The spatially-resolved cathodoluminescence (CL) spectra exhibit a sharp strong near-band-edge (NBE) emission in the ultraviolet range and a negligible green emission.
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Study of tonsillectomy for IgA nephropathy patients: short- and longer-term observation.
Int Urol Nephrol
PUBLISHED: 07-06-2013
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We observed serum parameters and urinary findings of IgA nephropathy (IgAN) patients in the short and longer time after tonsillectomy, to provide evidences to clarify the role of tonsils in the pathogenesis of IgAN and the feasibility of tonsillectomy for IgAN patients.
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Opioid receptors mediate enhancement of ACh-induced aorta relaxation by chronic intermittent hypobaric hypoxia.
Sheng Li Xue Bao
PUBLISHED: 06-22-2013
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The present study was designed to investigate the role of opioid receptors in the vasorelaxation effect of chronic intermittent hypobaric hypoxia (CIHH) in thoracic aorta rings and the underlying mechanism in rats. Adult male Sprague-Dawley (SD) rats were randomly divided into 2 groups: CIHH treatment group and control group. The rats in CIHH group were exposed to hypoxia in a hypobaric chamber (simulated 5 000 m altitude) for 28 days, 6 h per day. The rats in control group were kept in the same environment as CIHH rats except no hypoxia exposure. The relaxation of thoracic aorta rings was recorded by organ bath perfusion technique, and expression of opioid receptors was measured by Western blot. Results are shown as follows. (1) The acetylcholine (ACh)-induced endothelium-dependent relaxation of thoracic aorta in CIHH rats was increased obviously in a concentration-dependent manner compared with that in control rats (P < 0.05). (2) This enhancement of ACh-induced relaxation in CIHH rats was abolished by naloxone, a non-specific opioid receptor blocker (P < 0.05). (3) The expressions of ?, ? and ? opioid receptors in thoracic aorta of CIHH rats were up-regulated compared with those in control rats (P < 0.05). (4) The enhancement of CIHH on relaxation of thoracic aorta was reversed by glibenclamide, an ATP-sensitive potassium channel (KATP) blocker (P < 0.05). The results suggest that opioid receptors are involved in CIHH-enhanced ACh-induced vasorelaxation of thoracic aorta through KATP channel pathways.
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[The value of chest CT features evaluating the severity and prognosis for acute pancreatitis].
Sichuan Da Xue Xue Bao Yi Xue Ban
PUBLISHED: 06-11-2013
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To analyze the chest CT imaging features of AP and explore the clinical value of diagnosis and prognosis for acute pancreatitis.
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Wedelolactone inhibits LPS-induced pro-inflammation via NF-kappaB Pathway in RAW 264.7 cells.
J. Biomed. Sci.
PUBLISHED: 05-09-2013
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Wedelolactone (WEL), a major coumestan ingredient in Wedelia chinensis, has been used to treat septic shock, hepatitis and venom poisoning in traditional Chinese medicines. The objective of the study was to elucidate the anti-inflammatory effects and mechanism of WEL with a cellular model of lipopolysaccharide (LPS)-induced RAW264.7 cells.
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Reconstitution and characterization of eukaryotic N6-threonylcarbamoylation of tRNA using a minimal enzyme system.
Nucleic Acids Res.
PUBLISHED: 04-25-2013
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The universally conserved Kae1/Qri7/YgjD and Sua5/YrdC protein families have been implicated in growth, telomere homeostasis, transcription and the N6-threonylcarbamoylation (t(6)A) of tRNA, an essential modification required for translational fidelity by the ribosome. In bacteria, YgjD orthologues operate in concert with the bacterial-specific proteins YeaZ and YjeE, whereas in archaeal and eukaryotic systems, Kae1 operates as part of a larger macromolecular assembly called KEOPS with Bud32, Cgi121, Gon7 and Pcc1 subunits. Qri7 orthologues function in the mitochondria and may represent the most primitive member of the Kae1/Qri7/YgjD protein family. In accordance with previous findings, we confirm that Qri7 complements Kae1 function and uncover that Qri7 complements the function of all KEOPS subunits in growth, t(6)A biosynthesis and, to a partial degree, telomere maintenance. These observations suggest that Kae1 provides a core essential function that other subunits within KEOPS have evolved to support. Consistent with this inference, Qri7 alone is sufficient for t(6)A biosynthesis with Sua5 in vitro. In addition, the 2.9 Å crystal structure of Qri7 reveals a simple homodimer arrangement that is supplanted by the heterodimerization of YgjD with YeaZ in bacteria and heterodimerization of Kae1 with Pcc1 in KEOPS. The partial complementation of telomere maintenance by Qri7 hints that KEOPS has evolved novel functions in higher organisms.
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Positive correlation between variants of lipid metabolism?related genes and coronary heart disease.
Mol Med Rep
PUBLISHED: 04-23-2013
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Four gene variants related to lipid metabolism (including the rs562338 and rs503662 variants of the APOB gene, the rs7767084 variant of the LPA gene and the rs2246942 variant of the LIPA gene) have been shown to be associated with coronary heart disease (CHD). The aim of the present study was to assess their association with CHD in the Han Chinese population and to assess the contribution of these gene variants to CHD. Using the standardized coronary angiography method, we enrolled 290 CHD patients and 193 non-CHD patients as non-CHD controls from Lihuili Hospital (Ningbo, China). In addition, we recruited 330 unrelated healthy volunteers as healthy controls from the Xi Men Community (Ningbo, China). Our results demonstrated that the rs503662 and rs562338 variants of the APOB gene were extremely rare in the Han Chinese population (minor allele frequency <1%). Genotype rs2246942-GG of the LIPA gene was associated with an increased risk of CHD [CHD cases versus healthy controls: P=0.04; odds ratio (OR)=1.63; 95% confidence interval (CI)=1.02-2.60). Genotype rs7767084-CC of the LPA gene was identified as a protective factor against CHD in females (CHD cases versus non-CHD controls: P=0.04, OR=0.21; CHD cases versus healthy controls: P=0.02, OR=0.21). The results of our meta-analysis indicated that rs7767084 was not associated with a high risk of CHD (P=0.83; combined OR=0.93; 95% CI=0.47-1.85). In the present study, two single nucleotide polymorphisms (SNPs) of genes involved in lipid metabolism (rs2246942 and rs7767084) were identified to be significantly associated with CHD in the Han Chinese population. Specifically, rs2246942-GG of the LIPA gene was a risk factor for CHD, while rs7767084-CC of the LPA gene was a protective factor against CHD in females. However, our meta-analysis indicated that rs7767084 is not associated with a higher risk of CHD.
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Transient focal cerebral ischemia induces long-term cognitive function deficit in an experimental ischemic stroke model.
Neurobiol. Dis.
PUBLISHED: 04-12-2013
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Vascular dementia ranks as the second leading cause of dementia in the United States. However, its underlying pathophysiological mechanism is not fully understood and no effective treatment is available. The purpose of the current study was to evaluate long-term cognitive deficits induced by transient middle cerebral artery occlusion (tMCAO) in rats and to investigate the underlying mechanism. Sprague-Dawley rats were subjected to tMCAO or sham surgery. Behavior tests for locomotor activity and cognitive function were conducted at 7 or 30days after stroke. Hippocampal long term potentiation (LTP) and involvement of GABAergic neurotransmission were evaluated at 30days after sham surgery or stroke. Immunohistochemistry and Western blot analyses were conducted to determine the effect of tMCAO on cell signaling in the hippocampus. Transient MCAO induced a progressive deficiency in spatial performance. At 30days after stroke, no neuron loss or synaptic marker change in the hippocampus were observed. LTP in both hippocampi was reduced at 30days after stroke. This LTP impairment was prevented by blocking GABAA receptors. In addition, ERK activity was significantly reduced in both hippocampi. In summary, we identified a progressive decline in spatial learning and memory after ischemic stroke that correlates with suppression of hippocampal LTP, elevation of GABAergic neurotransmission, and inhibition of ERK activation. Our results indicate that the attenuation of GABAergic activity or enhancement of ERK/MAPK activation in the hippocampus might be potential therapeutic approaches to prevent or attenuate cognitive impairment after ischemic stroke.
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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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