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Find video protocols related to scientific articles indexed in Pubmed.
Towards microfluidic-based depletion of stiff and fragile human red cells that accumulate during blood storage.
Lab Chip
PUBLISHED: 11-20-2014
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In this study, the effects of prolonged storage on several biophysical properties of red blood cells (RBCs) were investigated. Single cell deformability was used as an important criterion in determining subgroups of RBCs evolved during storage lesion. A deformability-based microfluidic cell sorting technology was applied, which demonstrates the ability to enrich and separate the less deformable subpopulations of stored blood. These less deformable RBC subpopulations were then associated with other important markers such as osmotic fragility indicating cell integrity as well as microparticle content. This work demonstrates a systematic methodology to both monitor and improve banked blood quality, thereby reducing risks related to blood transfusion.
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Pedicle screw piercer with warning device - A technique to increase accuracy of pedicle screw placement: A cadaveric study.
Indian J Orthop
PUBLISHED: 11-19-2014
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Pedicle screw fixation has achieved significant popularity amongst spinal surgeons for both single and multilevel spinal fusion. Suboptimal placements of pedicle screws may lead to neurological and vascular complications. There have been many advances in techniques available for navigating through the pedicle; however, these techniques are not without drawbacks. The purpose of this study was to investigate the efficacy and feasibility of the pedicle piercer with warning device.
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Gelatin quantification by oxygen-18 labeling and liquid chromatography- high resolution mass spectrometry.
J. Agric. Food Chem.
PUBLISHED: 11-19-2014
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Combined with high-performance liquid chromatography (HPLC) and linear-ion trap/Orbitrap high-resolution mass spectrometry, trypsin catalyzed 16O-to-18O exchange was used to establish an accurate quantitative method for the bovine or porcine gelatin. The sophisticated modifications for these two mammalian gelatins were unambiguously identified by accurate mass and tandem mass spectrometry. Eighteen marker peptides were successfully identified for the bovine and porcine gelatin, respectively. The gelatins were subjected to 18O or 16O labeling in the presence of trypsin and mixed together in various ratios for quantification. All the 18O-labeled peptides were also confirmed by accurate mass and tandem mass spectrometry. The ten marker peptides with strongest signal were chosen to calculate the average ratios of 18O-labeled and 16O-labeled gelatin. The measured ratios of 18O-labeled and 16O-labeled peptides were very closed to the mixing ratios of 20:1, 5:1, 1:1 and 1:5 with low standard deviation values. The samples with mixing ratio of 1:1 18O-labeled and 16O-labeled peptides were determined to 1.00 and 0.99 with the standard deviation of 0.02 and 0.04 for bovine and porcine gelatins, respectively, indicating high accuracy of this method. Trypsin-catalyzed 18O labeling was proved to be an excellent internal calibrant for gelatins. When combined with HPLC and high resolution mass spectrometry, it is an accurate and sensitive quantitative method for gelatin in the food industry.
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Clinical features and treatment of drug fever caused by antituberculosis drugs.
Clin Respir J
PUBLISHED: 11-10-2014
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To investigate the clinical features of antituberculosis drugs induced fever and the methods to deal with it.
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Development of monoclonal antibody-based sandwich ELISA for detection of dextran.
Monoclon Antib Immunodiagn Immunother
PUBLISHED: 10-31-2014
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Dextran as anti-nutritional factor is usually a result of bacteria activity and has associated serial problems during the process stream in the sugar industry and in medical therapy. A sensitive method is expected to detect dextran quantitatively. Here we generated four monoclonal antibodies (MAbs) against dextran using dextran T40 conjugated with bovine serum albumin (BSA) as immunogen in our lab following hybridoma protocol. Through pairwise, an MAb named D24 was determined to be conjugated with horseradish peroxidase (HRP) and was used in the establishment of a sensitive sandwich enzyme-linked immunosorbent assay (ELISA) method for determination of dextran, in which MAb D9 was chosen as a capture antibody. The detection limit and working scope of the developed sandwich ELISA method were 3.9?ng/mL and 7.8-500?ng/mL with a correlation coefficient of 0.9909. In addition, the cross-reaction assay demonstrated that the method possessed high specificity with no significant cross-reaction with dextran-related substances, and the recovery rate ranged from 96.35 to 102.00%, with coefficient of variation ranging from 1.58 to 6.94%. These results indicated that we developed a detection system of MAb-based sandwich ELISA to measure dextran and this system should be a potential tool to determine dextran levels.
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Persistence and toxin production by Clostridium difficile within human intestinal organoids results in disruption of epithelial paracellular barrier function.
Infect. Immun.
PUBLISHED: 10-15-2014
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Clostridium difficile is the leading cause of infectious nosocomial diarrhea. The pathogenesis of C. difficile infection (CDI) results from the interactions between the pathogen, the intestinal epithelium, host immune system and the gastrointestinal microbiota. Previous studies of the host-pathogen interaction in CDI have utilized either simple cell monolayers or in vivo models. While much has been learned utilizing these approaches, little is known about the direct interaction of the bacterium with a complex host epithelium. Here, we asked if human intestinal organoids (HIOs), which are derived from pluripotent stem cells and demonstrate small intestinal morphology and physiology, could be used to study the pathogenesis of the obligate anaerobe C. difficile. Vegetative C. difficile, microinjected into the lumen of HIOs, persisted in a viable state for up to twelve hours. Upon colonization with C. difficile VPI 10463 the HIO epithelium is markedly disrupted, resulting in loss of paracellular barrier function. Since similar effects were not observed when HIOs were colonized with the nontoxigenic C. difficile strain F200, we directly tested the role of toxin using TcdA and TcdB purified from VPI 10463. We show that injection of TcdA replicates the disruption of the epithelial barrier function and structure observed in HIOs colonized with the viable C. difficile.
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Fast in situ generated ?-polylysine-poly (ethylene glycol) hydrogels as tissue adhesives and hemostatic materials using an enzyme-catalyzed method.
J Biomater Appl
PUBLISHED: 10-05-2014
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In this study, novel bio-inspired in situ hydrogels as tissue adhesives and hemostatic materials were designed and prepared based on ?-polylysine-grafted poly(ethylene glycol) and tyramine via enzymatic cross-linking. The enzymatic cross-linked method enabled fast gelation within seconds, which facilitated its therapeutic applications. By changing the cross-linking conditions, the storage modulus of the hydrogels could be tunable and the mechanical strength influenced the tissue adhesiveness of the hydrogels. Besides, the hydrogels showed fine network structures with appropriate pore sizes, which were thought to be a contributing factor to the strong adhesiveness. Benefiting from the strong mechanical properties and fine network structures, the ?-polylysine-grafted poly(ethylene glycol) and tyramine hydrogels exhibited superior wound-healing and hemostatic ability compared to conventional and commercially available medical materials. Moreover, indirect cytotoxicity assessment indicated that the ?-polylysine-grafted poly(ethylene glycol) and tyramine hydrogels were nontoxic to the L929 cell. These results demonstrated that the enzymatic cross-linked in situ ?-polylysine hydrogels hold high potential for tissue sealants and hemostatic materials.
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One-step synthesis of graphene/polypyrrole nanofiber composites as cathode material for a biocompatible zinc/polymer battery.
ACS Appl Mater Interfaces
PUBLISHED: 09-18-2014
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The significance of developing implantable, biocompatible, miniature power sources operated in a low current range has become manifest in recent years to meet the demands of the fast-growing market for biomedical microdevices. In this work, we focus on developing high-performance cathode material for biocompatible zinc/polymer batteries utilizing biofluids as electrolyte. Conductive polymers and graphene are generally considered to be biocompatible and suitable for bioengineering applications. To harness the high electrical conductivity of graphene and the redox capability of polypyrrole (PPy), a polypyrrole fiber/graphene composite has been synthesized via a simple one-step route. This composite is highly conductive (141 S cm(-1)) and has a large specific surface area (561 m(2) g(-1)). It performs more effectively as the cathode material than pure polypyrrole fibers. The battery constructed with PPy fiber/reduced graphene oxide cathode and Zn anode delivered an energy density of 264 mWh g(-1) in 0.1 M phosphate-buffer saline.
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Protective Effect of CpG-Oligodeoxynucleotides Against Low- and High-LET Irradiation.
Cell. Physiol. Biochem.
PUBLISHED: 09-02-2014
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Background/Aims: CpG-oligodeoxynucleotides (ODNs) are synthetic DNA sequences containing unmethylated cytosine-guanine motifs with potent immunomodulatory effects. Previous reports showed a powerful protective effect of CpG-ODN against the damage induced by low-LET ?-rays. In this study, we explored whether CpG-ODN also protects against the damage induced by high-LET irradiation. Parallel experiments were performed with low-LET irradiation. Methods: RAW264.7 cells were incubated with 1 ?M of CpG-ODN after ?-ray or carbon-beam irradiation. Cell death was then measured by PI/DAPI double staining, cell survival was assessed by colony-formation assays, DNA damage was evaluated by comet assays, cell cycle was monitored by flow cytometry, and the levels of apoptosis-related proteins were detected by western blots. Results: When irradiated cells were treated with the CpG-ODN, cell viability decreased, cell survival increased, DNA damage and G2/M-phase arrest were ameliorated, and apoptosis was inhibited. Conclusions: The CpG-ODN showed protective effects against low-LET ?-ray and high-LET carbon-beam irradiation. These effects might be associated with the repair of DNA damage and inhibition of apoptosis. © 2014 S. Karger AG, Basel.
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The Relationship between the Plasma PCSK9 Levels and Platelet Indices in Patients with Stable Coronary Artery Disease.
J. Atheroscler. Thromb.
PUBLISHED: 09-02-2014
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Aim: Recent studies have shown that platelet indices are linked to metabolic and cardiovascular diseases, in addition to being markers of hemostasis. These studies suggested that they could be modified by various biomolecules, including lipids. Proprotein convertase subtilisin/kexin type 9 (PCSK9), a newly-identified member, plays a key role in lipid metabolism and atherosclerosis. Therefore, we evaluated the relationship between the plasma PCSK9 level and platelet indices. Methods: In this cross-sectional study, a total of 330 consecutive, stable coronary artery disease (CAD) patients were enrolled at our center between October 2012 and April 2014. The baseline clinical characteristics were collected, and the plasma PCSK9 levels were determined using an ELISA. The associations between PCSK9 and the platelet indices were investigated. Results: The plasma PCSK9 levels were positively correlated with the platelet (PLT) count and plateletcrit (PCT) (r=0.218, p?0.001; r=0.250, p?0.001; respectively), while no correlation of PCSK9 with either the mean platelet volume (MPV) or platelet distribution width (PDW) was found. The association of PCSK9 with the PLT and PCT remained after adjusting for cardiometabolic risk factors (?=0.300, p?0.001; ?=0.269, p?0.01; respectively), but the latter disappeared when further adjusted for inflammatory markers (?=0.212, p?0.05; ?=0.151, p=NS). Additionally, a correlation analysis performed according to the number of diseased vessels showed that PCSK9 was related to the PLT and PCT in patients with single-, two- or multi-vessel disease, with a particularly strong correlation with two-vessel disease. Conclusions: The plasma PCSK9 levels are positively associated with the PLT count in CAD patients, suggesting a potential link between PCSK9 and platelets that may be involved in atherosclerosis and metabolic disorders.
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Hydrogen sulfide inhibits Cav3.2 T-type Ca2+ channels.
FASEB J.
PUBLISHED: 09-02-2014
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The importance of H2S as a physiological signaling molecule continues to develop, and ion channels are emerging as a major family of target proteins through which H2S exerts many actions. The purpose of the present study was to investigate its effects on T-type Ca(2+) channels. Using patch-clamp electrophysiology, we demonstrate that the H2S donor, NaHS (10 ?M-1 mM) selectively inhibits Cav3.2 T-type channels heterologously expressed in HEK293 cells, whereas Cav3.1 and Cav3.3 channels were unaffected. The sensitivity of Cav3.2 channels to H2S required the presence of the redox-sensitive extracellular residue H191, which is also required for tonic binding of Zn(2+) to this channel. Chelation of Zn(2+) with N,N,N',N'-tetra-2-picolylethylenediamine prevented channel inhibition by H2S and also reversed H2S inhibition when applied after H2S exposure, suggesting that H2S may act via increasing the affinity of the channel for extracellular Zn(2+) binding. Inhibition of native T-type channels in 3 cell lines correlated with expression of Cav3.2 and not Cav3.1 channels. Notably, H2S also inhibited native T-type (primarily Cav3.2) channels in sensory dorsal root ganglion neurons. Our data demonstrate a novel target for H2S regulation, the T-type Ca(2+) channel Cav3.2, and suggest that such modulation cannot account for the pronociceptive effects of this gasotransmitter.-Elies, J., Scragg, J. L., Huang, S., Dallas, M. L., Huang, D., MacDougall, D., Boyle, J. P. Gamper, N., Peers, C. Hydrogen sulfide inhibits Cav3.2 T-type Ca(2+) channels.
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Enhanced utility of family-centered diagnostic exome sequencing with inheritance model-based analysis: results from 500 unselected families with undiagnosed genetic conditions.
Genet. Med.
PUBLISHED: 08-27-2014
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Purpose:Diagnostic exome sequencing was immediately successful in diagnosing patients in whom traditional technologies were uninformative. Herein, we provide the results from the first 500 probands referred to a clinical laboratory for diagnostic exome sequencing.Methods:Family-based exome sequencing included whole-exome sequencing followed by family inheritance-based model filtering, comprehensive medical review, familial cosegregation analysis, and analysis of novel genes.Results:A positive or likely positive result in a characterized gene was identified in 30% of patients (152/500). A novel gene finding was identified in 7.5% of patients (31/416). The highest diagnostic rates were observed among patients with ataxia, multiple congenital anomalies, and epilepsy (44, 36, and 35%, respectively). Twenty-three percent of positive findings were within genes characterized within the past 2 years. The diagnostic rate was significantly higher among families undergoing a trio (37%) as compared with a singleton (21%) whole-exome testing strategy.Conclusion:Overall, we present results from the largest clinical cohort of diagnostic exome sequencing cases to date. These data demonstrate the utility of family-based exome sequencing and analysis to obtain the highest reported detection rate in an unselected clinical cohort, illustrating the utility of diagnostic exome sequencing as a transformative technology for the molecular diagnosis of genetic disease.Genet Med advance online publication 06 November 2014Genetics in Medicine (2014); doi:10.1038/gim.2014.154.
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Parkin-mediated K63-polyubiquitination targets ubiquitin C-terminal hydrolase L1 for degradation by the autophagy-lysosome system.
Cell. Mol. Life Sci.
PUBLISHED: 08-26-2014
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Ubiquitin C-terminal hydrolase L1 (UCH-L1) is a key neuronal deubiquitinating enzyme which is mutated in Parkinson disease (PD) and in childhood-onset neurodegenerative disorder with optic atrophy. Furthermore, reduced UCH-L1 protein levels are associated with a number of neurodegenerative diseases, whereas up-regulation of UCH-L1 protein expression is found in multiple types of cancer. However, very little is known about how UCH-L1 protein level is regulated in cells. Here, we report that UCH-L1 is a novel interactor and substrate of PD-linked E3 ubiquitin-protein ligase parkin. We find that parkin mediates K63-linked polyubiquitination of UCH-L1 in cooperation with the Ubc13/Uev1a E2 ubiquitin-conjugating enzyme complex and promotes UCH-L1 degradation by the autophagy-lysosome pathway. Targeted disruption of parkin gene expression in mice causes a significant decrease in UCH-L1 ubiquitination with a concomitant increase in UCH-L1 protein level in brain, supporting an in vivo role of parkin in regulating UCH-L1 ubiquitination and degradation. Our findings reveal a direct link between parkin-mediated ubiquitin signaling and UCH-L1 regulation, and they have important implications for understanding the roles of these two proteins in health and disease.
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Maternal thermal environment induces plastic responses in the reproductive life history of oviparous lizards.
Physiol. Biochem. Zool.
PUBLISHED: 08-21-2014
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Adaptive plasticity may shift phenotypic traits close to a new optimum for directional selection and probably facilitates adaptive evolution in new environments. However, such plasticity has rarely been reported in life-history evolution, despite overwhelming evidence of life-history variation both among and within species. In this study, the temperatures experienced by gravid females of Scincella modesta were manipulated to identify maternally induced plasticity in reproductive traits and the significance of such changes in the evolution of life history. Consistent with the geographic pattern of life history, the study demonstrated that low temperatures delayed egg oviposition, resulting in a more advanced embryonic developmental stage at oviposition and shorter incubation periods compared with warm temperatures. In addition, females maintained at low temperatures produced larger eggs and hence heavier hatchlings than those at warm temperatures. This study demonstrated that environmental temperatures can induce plastic responses in egg retention and offspring size, and these maternally mediated changes in reproductive life history seem to be adaptive in the light of latitudinal clines of these traits in natural populations.
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MSC attenuate diabetes-induced functional impairment in adipocytes via secretion of insulin-like growth factor-1.
Biochem. Biophys. Res. Commun.
PUBLISHED: 08-21-2014
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The function of subcutaneous adipocytes in promoting wound healing is significantly suppressed in diabetic wounds. Recent studies have demonstrated the ability of mesenchymal stem cell (MSC) to ameliorate impaired diabetic wound healing. We hypothesized that MSC function may involve subcutaneous adipocytes. The abnormal function of subcutaneous adipocytes from STZ induced diabetic mice including glucose uptake and free fatty acid (FFA) secretion level were assessed. Then these cells were co-cultured with MSC via a transwell system to observe the changes of metabolic index and glucose transporter four (GLUT4) as well as phosphoinositide 3-kinase/protein kinase (PI3K/AKT) signaling pathway expression. The results of metabolic index suggest that MSC obviously attenuated the diabetes-induced functional impairment. Both mRNA and protein expression analyses showed that PI3K/AKT insulin signaling pathway and GLUT4 expression were up-regulated. These changes were substantially associated with a increased level of insulin-like growth factor-1 (IGF-1) secretion from MSC. These findings suggest that MSC could attenuate abnormal function of diabetic adipocytes by IGF-1secretion, which was more or less associated with the beneficial effects of MSC on improving diabetic wound healing.
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Majocchi's Granuloma after Topical Corticosteroids Therapy.
Case Rep Dermatol Med
PUBLISHED: 08-11-2014
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Majocchi's granuloma (MG) is an unusual but not rare dermatophyte infection of dermal and subcutaneous tissues. Dermatophytes usually result in the infections of hair, epidermis, and nail, and are rarely involved in deep cutaneous and subcutaneous tissues. Now it is considered that MG includes two forms: one is a small perifollicular papular form and the other is a deep subcutaneous nodular form; the front one mainly occurs in healthy individuals and the latter one usually presents in immunocompromised hosts. The clinical manifestations of MG are many and varied, except the common presentations of erythema, papule and nodules, and Kaposi sarcoma-like and molluscum-like lesions have been reported in literatures (Kim et al. (2011), Bord et al. (2007), and Lillis et al. (2010)). This characteristic induces the difficulty of diagnosis, and thus it is so important and necessary to make direct microscopical and histological examinations. We describe a case of MG over the face in a patient who had been treated with topical corticosteroids over a long time.
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The role of fibroblast growth factor 21 in the pathogenesis of liver disease: a novel predictor and therapeutic target.
Expert Opin. Ther. Targets
PUBLISHED: 07-31-2014
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Fibroblast growth factor 21 (FGF21) is one of the FGF family members that is produced mainly by tissues with high metabolic activity such as liver, pancreas, muscle and adipose tissue. The major function of FGF21 is to improve insulin sensitivity, ameliorate hepatic steatosis and enhance energy expenditure. Recently, several studies have reported a correlation between FGF21 and liver disease with numerous cross-sectional studies demonstrating significant correlation. This review will focus on the role of FGF21 in the pathogenesis of liver disease and its potential role as a biomarker and a new target for therapeutic intervention.
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Storage of Gold Nanoclusters in Muscle Leads to their Biphasic in Vivo Clearance.
Small
PUBLISHED: 07-25-2014
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Ultrasmall gold nanoclusters (Au NCs) show great potential in biomedical applications. Long-term biodistribution, retention, toxicity, and pharmacokinetics profiles are pre-requisites in their potential clinical applications. Here, the biodistribution, clearance, and toxicity of one widely used Au NC species-glutathione-protected Au NCs or GSH-Au NCs-are systematically investigated over a relatively long period of 90 days in mice. Most of the Au NCs are cleared at 30 days post injection (p.i.) with a major accumulation in liver and kidney. However, it is surprising that an abnormal increase of the Au amount in the heart, liver, spleen, lung, and testis is observed at 60 and 90 days p.i., indicating that the injected Au NCs form a V-shaped time-dependent distribution profile in various organs. Further investigations reveal that Au NCs are steadily accumulating in the muscle in the first 30 days p.i., and the as-stored Au NCs gradually release into the blood in 30-90 days p.i., which induces a re-distribution and re-accumulation of Au NCs in all blood-rich organs. Further hematology and biochemistry studies show that the re-accumulation of Au NCs still causes some liver toxicity at 30 days p.i. The muscle storage and subsequent release may give rise to the potential accumulation and toxicity risk of functional nanomaterials over long periods of time.
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Basophil count, a marker for disease activity in systemic lupus erythematosus.
Clin. Rheumatol.
PUBLISHED: 07-18-2014
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Systemic lupus erythematosus (SLE) is a chronic multisystem autoimmune disease, with frequent flares amid remissions. Basophils contribute to the immunopathogenesis of SLE. This retrospective clinical study evaluated blood basophil count as a potential marker of SLE activity. This study included 213 patients with SLE, 70 with non-SLE chronic kidney disease (CKD), and 100 healthy volunteers. SLE disease activity was scored using the SLE Disease Activity Index (SLEDAI). Baseline and post-immunosuppressant bioparameters were compared in patients with active SLE, with second samples taken at total SLEDAI ?4. Blood basophil counts and other conventional biomarkers were compared among the groups. Among the 213 SLE patients (192 women, 21 men; mean age 33.0?±?12.0 years), 149 had active disease. Basophil counts were significantly lower in patients with SLE than in patients with non-SLE CKD and healthy controls (0.009?±?0.010 vs. 0.025?±?0.015 vs. 0.022?±?0.010?×?10(9)/L, p?<0.001), and lower in patients with active than inactive SLE (0.008?±?0.009 vs. 0.014?±?0.012?×?10(9)/L, p?<0.001). Basophil counts in SLE patients were significantly higher after than before immunosuppressive treatment (0.021?±?0.017 vs. 0.008?±?0.008?×?10(9)/L, p?<0.001) and correlated with total SLEDAI score (r?=?-0.30, p?<0.001). Receiver operator curve analysis showed that basophil counts were similar to conventional markers (leukocytes, platelets, and double-stranded (ds) DNA IgG) in differentiating active from inactive SLE. These findings indicate that blood basophil counts may be a useful biomarker in evaluating SLE activity.
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L-Arabinose isomerase and its use for biotechnological production of rare sugars.
Appl. Microbiol. Biotechnol.
PUBLISHED: 07-18-2014
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L-Arabinose isomerase (AI), a key enzyme in the microbial pentose phosphate pathway, has been regarded as an important biological catalyst in rare sugar production. This enzyme could isomerize L-arabinose into L-ribulose, as well as D-galactose into D-tagatose. Both the two monosaccharides show excellent commercial values in food and pharmaceutical industries. With the identification of novel AI family members, some of them have exhibited remarkable potential in industrial applications. The biological production processes for D-tagatose and L-ribose (or L-ribulose) using AI have been developed and improved in recent years. Meanwhile, protein engineering techniques involving rational design has effectively enhanced the catalytic properties of various AIs. Moreover, the crystal structure of AI has been disclosed, which sheds light on the understanding of AI structure and catalytic mechanism at molecular levels. This article reports recent developments in (i) novel AI screening, (ii) AI-mediated rare sugar production processes, (iii) molecular modification of AI, and (iv) structural biology study of AI. Based on previous reports, an analysis of the future development has also been initiated.
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[Induction in vitro and stability of Mycobacterium tuberculosis resistance to ofloxacin].
Zhonghua Yu Fang Yi Xue Za Zhi
PUBLISHED: 06-28-2014
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To induct Mycobacterium tuberculosis (MTB) resistance with ofloxacin (Ofx) of stepwise increasing concentration in vitro, investigate stability to fluoroquinolone (FQs) antibiotic of MTB, and analyze the molecular mechanism and mutation specialty of drug resistance preliminarily.
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Syrinx resolution is correlated with the upward shifting of cerebellar tonsil following posterior fossa decompression in pediatric patients with Chiari malformation type I.
Eur Spine J
PUBLISHED: 06-23-2014
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Chiari malformation type I (CMI) is characterized by deformed hindbrain. This study aimed to quantitatively evaluate the alterations in position of hindbrain after Posterior fossa decompression (PFD), and to identify the factors associated with syrinx resolution in pediatric patients with CMI.
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Single-base-resolution methylomes of Populus trichocarpa reveal the association between DNA methylation and drought stress.
BMC Genet.
PUBLISHED: 06-20-2014
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DNA methylation is an important biological form of epigenetic modification, playing key roles in plant development and environmental responses.
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Genome-wide identification and functional prediction of novel and drought-responsive lincRNAs in Populus trichocarpa.
J. Exp. Bot.
PUBLISHED: 06-19-2014
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Protein-coding genes are considered to be a dominant component of the eukaryotic transcriptome; however, many studies have shown that intergenic, non-coding transcripts also play an important role. Long intergenic non-coding RNAs (lincRNAs) were found to play a vital role in human and Arabidopsis. However, lincRNAs and their regulatory roles remain poorly characterized in woody plants, especially Populus trichocarpa (P. trichocarpa). A large set of Populus RNA-Seq data were examined with high sequencing depth under control and drought conditions and a total of 2542 lincRNA candidates were identified. In total, 51 lincRNAs and 20 lincRNAs were identified as putative targets and target mimics of known Populus miRNAs, respectively. A total of 504 lincRNAs were found to be drought responsive, eight of which were confirmed by RT-qPCR. These findings provide a comprehensive view of Populus lincRNAs, which will enable in-depth functional analysis.
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Bactericidal properties and biocompatibility of a gentamicin-loaded Fe3O4/carbonated hydroxyapatite coating.
Colloids Surf B Biointerfaces
PUBLISHED: 06-17-2014
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Postoperative implant-associated infection remains a serious complication in total joint arthroplasty (TJA) surgery. The addition of antibiotics to bone cement is used as an antimicrobial prophylaxis in cemented joint arthroplasty; however, in cementless arthroplasty, there are no comparable measures for the local delivery of antibiotics. In this study, a gentamicin-loaded Fe3O4/carbonated hydroxyapatite coating (Gent-MCHC) was fabricated according to the following steps: (i) deposition of Fe3O4/CaCO3 particles on Ti6Al4V substrates by electrophoretic deposition; (ii) conversions of MCHC from Fe3O4/CaCO3 coatings by chemical treatment; and (iii) formation of Gent-MCHC by loading gentamicin into MCHC. MCHC possessed mesoporous structure with a pore size of about 3.8nm and magnetic property with the saturation magnetization strength of about 4.03emu/g. Gent-MCHC had higher drug loading efficiency and drug release capacity, and superior biocompatibility and mitogenic activity than Ti6Al4V. Moreover, Gent-MCHC deterred bacterial adhesion and prevented biofilm formation. These results demonstrate that Gent-MCHC can be used as a local drug delivery system to prevent implant-associated infection in TJA surgery.
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Cell localisation of gadolinium-based nanoparticles and related radiosensitising efficacy in glioblastoma cells.
Cancer Nanotechnol
PUBLISHED: 05-27-2014
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Recently, the addition of nanoparticles (NPs) has been proposed as a new strategy to enhance the effect of radiotherapy particularly in the treatment of aggressive tumors such as glioblastoma. The physical processes involved in radiosensitisation by nanoparticles have been well studied although further understanding of its biological impact is still lacking, and this includes the localisation of these NPs in the target cells. Most studies were performed with NPs tagged with fluorescent markers. However, the presence of these markers can influence the NPs uptake and localisation. In this study, a set of methods was used to unambiguously and fully characterise the uptake of label-free NPs, their co-localisation with cell organelles, and their radiosensitising efficacy. This set was applied to the case of gadolinium-based nanoparticles (GdBN) used to amplify the radiation killing of U87 glioblastoma cells extracted from highly aggressive human tumor. For the first time, Synchrotron Radiation Deep UV (SR-DUV) microscopy is proposed as a new tool to track label-free GdBN. It confirmed the localisation of the NPs in the cytoplasm of U87 cells and the absence of NPs in the nucleus. In a second step, Transmission Electron Microscopy (TEM) demonstrated that GdBN penetrate cells by endocytosis. Third, using confocal microscopy it was found that GdBN co-localise with lysosomes but not with mitochondria. Finally, clonogenic assay measurements proved that the presence of NPs in the lysosomes induces a neat amplification of the killing of glioblastoma cells irradiated by gamma rays. The set of combined experimental protocols-TEM, SR-DUV and confocal microscopy-demonstrates a new standard method to study the localisation of label-free NPs together with their radiosensitising properties. This will further the understanding of NP-induced radiosentisation and contribute to the development of nanoagents for radiotherapy.
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Mitochondrial myopathy, lactic acidosis, and sideroblastic anemia (MLASA) plus associated with a novel de novo mutation (m.8969G>A) in the mitochondrial encoded ATP6 gene.
Mol. Genet. Metab.
PUBLISHED: 05-25-2014
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Mitochondrial myopathy, lactic acidosis and sideroblastic anemia (MLASA) is a rare mitochondrial disorder that has previously been associated with mutations in PUS1 and YARS2. In the present report, we describe a 6-year old male with an MLASA plus phenotype. This patient had features of MLASA in the setting of developmental delay, sensorineural hearing loss, epilepsy, agenesis of the corpus callosum, failure to thrive, and stroke-like episodes. Sequencing of the mitochondrial genome identified a novel de novo, heteroplasmic mutation in the mitochondrial DNA (mtDNA) encoded ATP6 gene (m.8969G>A, p.S148N). Whole exome sequencing did not identify mutations or variants in PUS1 or YARS2 or any known nuclear genes that could affect mitochondrial function and explain this phenotype. Studies of fibroblasts derived from the patient revealed a decrease in oligomycin-sensitive respiration, a finding which is consistent with a complex V defect. Thus, this mutation in MT-ATP6 may represent the first mtDNA point mutation associated with the MLASA phenotype.
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A novel bHLH transcription factor PebHLH35 from Populus euphratica confers drought tolerance through regulating stomatal development, photosynthesis and growth in Arabidopsis.
Biochem. Biophys. Res. Commun.
PUBLISHED: 05-25-2014
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Plant basic helix-loop-helix (bHLH) transcription factors (TFs) are involved in a variety of physiological processes including the regulation of plant responses to various abiotic stresses. However, few drought-responsive bHLH family members in Populus have been reported. In this study, a novel bHLH gene (PebHLH35) was cloned from Populus euphratica. Expression analysis in P. euphratica revealed that PebHLH35 was induced by drought and abscisic acid. Subcellular localization studies using a PebHLH35-GFP fusion showed that the protein was localized to the nucleus. Ectopic overexpression of PebHLH35 in Arabidopsis resulted in a longer primary root, more leaves, and a greater leaf area under well-watered conditions compared with vector control plants. Notably, PebHLH35 overexpression lines showed enhanced tolerance to water-deficit stress. This finding was supported by anatomical and physiological analyses, which revealed a reduced stomatal density, stomatal aperture, transpiration rate, and water loss, and a higher chlorophyll content and photosynthetic rate. Our results suggest that PebHLH35 functions as a positive regulator of drought stress responses by regulating stomatal density, stomatal aperture, photosynthesis and growth.
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Angiogenic Effect of Mesenchymal Stem Cells as a Therapeutic Target for Enhancing Diabetic Wound Healing.
Int J Low Extrem Wounds
PUBLISHED: 05-25-2014
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Impaired wound-healing activity in diabetes could result from several factors, including severely damaged angiogenic responses, which can affect wound healing process to cause delayed wound repair. Mesenchymal stem cells (MSCs) have been shown to enhance wound healing via multiple effects, including promoting angiogenesis both in vitro and in vivo; however, the mechanisms involved in enhancing diabetic wound healing are barely understood. This article reviews the recent literatures on MSCs treatment for promoting angiogenesis or vascularization in diabetic wounds and the potential mechanisms involved, with an emphasis on the role of paracrine soluble factors. Meanwhile, the potential benefits and related risks associated with the therapeutic use of MSCs have been presented and may lead to better understanding of the influence of MSCs without increasing potential risks. Further investigation will be required to determine the molecular basis of paracrine mechanisms and regulated angiogenesis of MSCs for its rational manipulation for impaired angiogenesis repair and diabetic wound healing.
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Relation of circulating PCSK9 concentration to fibrinogen in patients with stable coronary artery disease.
J Clin Lipidol
PUBLISHED: 05-14-2014
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Both proprotein convertase subtilisin/kexin type 9 (PCSK9) and fibrinogen have been established as novel markers for atherosclerotic diseases. However, no data are available regarding the relationship between circulating PCSK9 and fibrinogen concentration up to now.
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MicroRNA-30a promotes invasiveness and metastasis in vitro and in vivo through epithelial-mesenchymal transition and results in poor survival of nasopharyngeal carcinoma patients.
Exp. Biol. Med. (Maywood)
PUBLISHED: 05-08-2014
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Although microRNA-30a (miR-30a) has been shown to regulate cancer metastasis, the molecular mechanism has not yet been clearly elucidated in nasopharyngeal carcinoma (NPC). The present study was to investigate the miR-30a expression pattern and its potential functions and further to identify its target gene and corresponding clinical applications in NPC. MiR-30a was identified to be down-regulated in NPC primary tumors compared with metastatic tumors using quantitative real-time PCR. Furthermore, over-expression of miR-30a transfected with precursor increased the ability of metastasis and invasion of NPC tumor cells in vivo and in vitro. E-cadherin was screened as a putative target gene of miR-30a by computational algorithms. Luciferase reporter assays showed that over-expression of miR-30a directly reduced the activity of a luciferase transcript combined with the 3'-untranslated region (3'-UTR) of E-cadherin. Kaplan-Meier survival analysis and log-rank test were analyzed for 1077 NPC patients for overall survival, indicating that a high expression of E-cadherin was beneficial for NPC prognosis (P?=?0.001). Importantly, NPC patients with high expression of E-cadherin had much lower risk of poor prognosis (hazard ratio?=?0.757, P?=?0.017) using multivariate analysis. In conclusion, miR-30a could play an important role in regulating NPC metastasis and potentially provide useful guidelines for individualized therapy.
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Linking genetic variation in human Toll-like receptor 5 genes to the gut microbiome's potential to cause inflammation.
Immunol. Lett.
PUBLISHED: 04-21-2014
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Immunodeficiencies can lead to alterations of the gut microbiome that render it pathogenic and capable of transmitting disease to naïve hosts. Here, we review the role of Toll-like receptor (TLR) 5, the innate receptor for bacterial flagellin, in immune responses to the normal gut microbiota with a focus its role on adaptive immunity. Loss of TLR5 has profound effects on the microbiota that include greater temporal instability of major lineages and upregulation of flagellar motility genes that may be linked to the reduced levels of anti-flagellin antibodies in the TLR5(-/-) host. A variety of human TLR5 gene alleles exist that also associated with inflammatory conditions and may do so via effects on the gut microbiome and altered host-microbial crosstalk.
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[Natural history of scoliosis after posterior fossa decompression in patients with Chiari malformation/syringomyelia].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 04-12-2014
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To explore the natural history of scoliosis after posterior fossa decompression (PFD) in patients with Chiari malformation/syringomyelia and examine the risk factors associated with curve progression.
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In vivo splenic clearance correlates with in vitro deformability of red blood cells from Plasmodium yoelii-infected mice.
Infect. Immun.
PUBLISHED: 03-31-2014
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Recent experimental and clinical studies suggest a crucial role of mechanical splenic filtration in the host's defense against malaria parasites. Subtle changes in red blood cell (RBC) deformability, caused by infection or drug treatment, could influence the pathophysiological outcome. However, in vitro deformability measurements have not been directly linked in vivo with the splenic clearance of RBCs. In this study, mice infected with malaria-inducing Plasmodium yoelii revealed that chloroquine treatment could lead to significant alterations to RBC deformability and increase clearance of both infected and uninfected RBCs in vivo. These results have clear implications for the mechanism of human malarial anemia, a severe pathological condition affecting malaria patients.
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Improved glycation after ultrasonic pretreatment revealed by high-performance liquid chromatography-linear ion trap/Orbitrap high-resolution mass spectrometry.
J. Agric. Food Chem.
PUBLISHED: 03-14-2014
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The glycation extent of bovine serum albumin (BSA) before and after ultrasonication was evaluated by MALDI-TOF and Orbitrap mass spectrometry. Ultrasonic pretreatment significantly improved the incorporation of galactose to BSA. Prior to ultrasonic pretreatment, only 12 sites (11 lysines and 1 arginine) were glycated, whereas the number of glycation sites was increased to 42, including 39 lysines and 3 arginines, after treatment. Average degree of substitution per peptide molecule of BSA (DSP) was used to evaluate the glycation level for each glycation site. The ultrasonic pretreatment significantly improved the DSP value of all glycation sites. The prevalently promoted glycation by ultrasonic pretreatment suggests that ultrasonication improves glycation through altering the structure of BSA throughout all three domains. An ultrahigh-resolution linear ion trap Orbitrap mass spectrometer facilitates unambiguous localization of glycation sites, allowing an in-depth analysis of the nature and extent of protein glycation at the molecular level. High-intensity ultrasonication can greatly improve protein glycation and, therefore, opens new routes to modify the functionality of proteins in a positive way.
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Mesenchymal stromal cells enhance wound healing by ameliorating impaired metabolism in diabetic mice.
Cytotherapy
PUBLISHED: 03-13-2014
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Mesenchymal stromal cells (MSCs) have been documented to improve delayed wound healing in diabetes, but the underlying mechanism remains obscure. We aimed to investigate whether the therapeutic effects on wounds was associated with metabolic alterations by paracrine action of MSCs.
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Structural changes of ultrasonicated bovine serum albumin revealed by hydrogen-deuterium exchange and mass spectrometry.
Anal Bioanal Chem
PUBLISHED: 03-10-2014
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The structural changes of bovine serum albumin (BSA) under high-intensity ultrasonication were investigated by fluorescence spectroscopy and mass spectrometry. Evidence for the ultrasonication-induced conformational changes of BSA was provided by the intensity changes and maximum-wavelength shift in fluorescence spectrometry. Matrix-assisted laser desorption-ionization time-of-flight mass spectroscopy (MALDI-TOF MS) revealed the increased intensity of the peak at the charge state +5 and a newly emerged peak at charge state +6, indicating that the protein became unfolded after ultrasonication. Prevalent unfolding of BSA after ultrasonication was revealed by hydrogen-deuterium exchange coupled with mass spectrometry (HDX-MS). Increased intensity and duration of ultrasonication further promoted the unfolding of the protein. The unfolding induced by ultrasonication goes through an intermediate state similar to that induced by a low concentration of denaturant.
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A monoclonal antibody targeting neuropilin-1 inhibits adhesion of MCF7 breast cancer cells to fibronectin by suppressing the FAK/p130cas signaling pathway.
Anticancer Drugs
PUBLISHED: 03-04-2014
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Neuropilin-1 (NRP-1) is a nontyrosine kinase coreceptor for semaphorin 3A and the vascular endothelial growth factor involved in tumor angiogenesis, growth, and metastasis and is regarded as a promising target for cancer therapy. In the present study, we investigated the effects of an anti-NRP-1 monoclonal antibody (mAb) that we generated for MCF7 breast cancer cellular adhesion studies. MTT, colony formation, and adhesion assays showed that our anti-NRP-1 mAb dose-dependently inhibited MCF7 proliferation and fibronectin adhesion, leading to a rounded cellular morphology. Further, rhodamine phalloidin stain revealed that fibronectin-dependent formation of actin stress fibers was inhibited by anti-NRP-1 mAb. Immunoprecipitation and western blot showed that anti-NRP-1 mAb treatment inhibited the formation of NRP-1-?5?1 integrin complexes and suppressed the phosphorylation of focal adhesion kinase and p130cas in MCF7 cells. These findings contribute to further understanding the NRP-1 function in cell adhesion and tumor metastasis. Moreover, our anti-NRP-1 mAb is a prospective drug candidate for tumor treatment.
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Expanding the clinical and mutational spectrum of Kaufman oculocerebrofacial syndrome with biallelic UBE3B mutations.
Hum. Genet.
PUBLISHED: 02-25-2014
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Biallelic mutations of UBE3B have recently been shown to cause Kaufman oculocerebrofacial syndrome (also reported as blepharophimosis-ptosis-intellectual disability syndrome), an autosomal recessive condition characterized by hypotonia, developmental delay, intellectual disability, congenital anomalies, characteristic facial dysmorphic features, and low cholesterol levels. To date, six patients with either missense mutations affecting the UBE3B HECT domain or truncating mutations have been described. Here, we report on the identification of homozygous or compound heterozygous UBE3B mutations in six additional patients from five unrelated families using either targeted UBE3B sequencing in individuals with suggestive facial dysmorphic features, or exome sequencing. Our results expand the clinical and mutational spectrum of the UBE3B-related disorder in several ways. First, we have identified UBE3B mutations in individuals who previously received distinct clinical diagnoses: two sibs with Toriello-Carey syndrome as well as the patient reported to have a "new" syndrome by Buntinx and Majewski in 1990. Second, we describe the adult phenotype and clinical variability of the syndrome. Third, we report on the first instance of homozygous missense alterations outside the HECT domain of UBE3B, observed in a patient with mildly dysmorphic facial features. We conclude that UBE3B mutations cause a clinically recognizable and possibly underdiagnosed syndrome characterized by distinct craniofacial features, hypotonia, failure to thrive, eye abnormalities, other congenital malformations, low cholesterol levels, and severe intellectual disability. We review the UBE3B-associated phenotypes, including forms that can mimick Toriello-Carey syndrome, and suggest the single designation "Kaufman oculocerebrofacial syndrome".
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Brace treatment versus observation alone for scoliosis associated with Chiari I malformation following posterior fossa decompression: a cohort study of 54 patients.
Eur Spine J
PUBLISHED: 02-24-2014
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To be deemed effective in preventing curve progression, brace treatment should show alteration of the expected natural history. Most of the reported studies on the effect of bracing on the evolution of Chiari malformation-associated scoliosis (CMS) following posterior fossa decompression (PFD) were small series with inconclusive results. The goal of this study was to investigate whether post-PFD brace treatment for CMS produces better outcomes than observation alone.
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Profiling plasma microRNA in nasopharyngeal carcinoma with deep sequencing.
Clin. Chem.
PUBLISHED: 02-21-2014
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The goal of this study was to establish a plasma microRNA profile by use of next-generation sequencing that could aid in assessment of patient prognosis in nasopharyngeal carcinoma (NPC).
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Effects of a freeze-dried juice blend powder on exercise-induced inflammation, oxidative stress, and immune function in cyclists.
Appl Physiol Nutr Metab
PUBLISHED: 02-21-2014
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A freeze-dried fruit and vegetable juice powder (JUICE) was investigated as a countermeasure nutritional strategy to exercise-induced inflammation, oxidative stress, and immune perturbations in trained cyclists. Thirty-four cyclists (25 male, 9 female) were randomized to control (nonJUICE) or JUICE for 17 days. JUICE provided 230 mg·day(-1) of flavonoids, doubling the typical adult daily intake. During a 3-d period of intensified exercise (days 15-17), subjects cycled at 70%-75% V?O2max for 2.25 h per day, followed by a 15-min time trial. Blood samples were collected presupplementation, post supplementation (pre-exercise), and immediately and 14-h post exercise on the third day of exercise. Samples were analyzed for inflammation (interleukin (IL)-6, IL-8; tumor necrosis factor alpha (TNF?); monocyte chemoattractant protein-1 (MCP-1)), oxidative stress (oxygen radical absorbance capacity (ORAC), ferric reducing ability of plasma (FRAP), reduced and oxidized glutathione, protein carbonyls), and innate immune function (granulocyte (G-PHAG) and monocyte (M-PHAG) phagocytosis and oxidative burst activity). A 2 (group) × 4 (time points) repeated measures ANOVA revealed significant time effects due to 3 days of exercise for IL-6 (396% increase), IL-8 (78% increase), TNF? (12% increase), MCP-1 (30% increase), G-PHAG (38% increase), M-PHAG (36% increase), FRAP (12.6% increase), ORAC (11% decrease at 14 h post exercise), and protein carbonyls (82% increase at 14 h post exercise) (p < 0.01). No significant interaction effects were found for any of the physiological measures. Although providing 695 gallic acid equivalents of polyphenols per day, JUICE treatment for 17 days did not change exercise-induced alterations in inflammation and oxidative stress or immune function in trained cyclists after a 3-day period of overreaching.
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Fabrication, characterization, and biocompatibility of ethyl cellulose/carbonated hydroxyapatite composite coatings on Ti6Al4V.
J Mater Sci Mater Med
PUBLISHED: 02-17-2014
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In order to improve the biocompatibility of metallic implants, bioactive components are often used as coatings so that a real bond with the surrounding bone tissue can be formed. We prepared ethyl cellulose/carbonated hydroxyapatite composite coatings (ECHCs) on Ti6Al4V substrates with carbonated hydroxyapatite coatings (CHACs) without ethyl cellulose as controls. The inorganic constituent on the CHACs and ECHCs is calcium-deficient carbonated hydroxyapatite with a flaky texture and a low degree of crystallinity. The flaky carbonated hydroxyapatite plates aggregate to form macropores with an aperture size of around 0.5-2.0 ?m. The presence of ethyl cellulose provides superior morphology, contact angle, and biocompatibility characteristics. In comparison to CHACs, ECHCs exhibit a smoother, crack-free surface because the cracks are filled by ethyl cellulose. Moreover, the contact angle of ECHCs is 37.3°, greater than that of CHACs (13.0°). Surface biocompatibility was investigated by using human bone mesenchymal stem cells (hBMSCs). The attachment, spreadability, viability and proliferation of hBMSCs on ECHCs are superior to those on CHACs. Thus, the crack-free ECHCs have excellent biocompatibility and are appropriate for use as biological implants.
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Clinical features of coronary artery ectasia in the elderly.
J Geriatr Cardiol
PUBLISHED: 02-08-2014
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To investigate the incidence, imaging and clinical characteristics in elderly patients with coronary artery ectasia (CAE).
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Clinical features and mortality in Chinese with lupus nephritis and neuropsychiatric lupus: A 124-patient study.
J Res Med Sci
PUBLISHED: 02-05-2014
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Few investigation has focused on the patients with lupus nephritis (LN) and neuropsychiatric systemic lupus erythematosus (NPSLE). This study was aimed to investigate the clinical features, mortality, and the predictors for mortality of this group of patients.
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Detection of EML4-ALK Fusion Gene in Chinese Non-Small Cell Lung Cancer by Using a Sensitive Quantitative Real-Time Reverse Transcriptase PCR Technique.
Diagn. Mol. Pathol.
PUBLISHED: 02-04-2014
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Anaplastic lymphoma kinase (ALK) rearrangement is present in approximately 5% of lung adenocarcinoma. Clinical trials on ALK inhibitor phase I to III have shown an interesting disease control rate and acceptable tolerability in ALK rearrangement patients. In clinical application, the precise diagnostic strategy for identifying ALK rearrangements remains to be determined. In this study, ALK rearrangement was screened by using quantitative real-time reverse transcriptase polymerase chain reaction (qRT-PCR), direct sequencing, 2 fluorescence in situ hybridization (FISH) assays, and immunohistochemistry in 173 lung adenocarcinomas. We identified 18 cases (10.4%) with EML4-ALK fusion-positive by qRT-PCR, and all were positive for EML4-ALK fusion gene validated by direct sequencing. The result was consistent with that of other methods. Furthermore, of the 18 EML4-ALK fusion-positive cases, 16 (9.2%) were positive by using EML4-ALK fusion probe FISH, and 15 (8.7%) were positive by using ALK break-apart probe FISH and immunohistochemistry staining. Of the 18 ALK fusion-positive lung adenocarcinomas, 8 cases (44.4%) were histologically diagnosed as subtypes of cribriform adenocarcinoma, 7 cases (38.9%) as cribriform adenocarcinoma mixed with papillary and/or mucinous pattern, 2 cases (11.1%) as papillary adenocarcinoma, and 1 case (5.6%) as mucinous adenocarcinoma. In the present study, the ALK rearrangement frequency detected by qRT-PCR in Chinese NSCLC patients was higher than that in the western populations. QRT-PCR is a rapid, sensitive technology that could be used as a screening tool for identifying EML4-ALK fusion-positive NSCLC patients who would be sensitive for receiving ALK inhibitor therapy.
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TGF-? favors bone marrow-derived dendritic cells to acquire tolerogenic properties.
Immunol. Invest.
PUBLISHED: 01-31-2014
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Dendritic cells (DCs) are the most powerful antigen-presenting cells that have an important role in the immunity and immune tolerance. Transforming growth factor ? (TGF-?) is a pleiotropic cytokine widely expressing in various tissues and cells, which regulates cellular proliferation, differentiation and apoptosis of several immune cells and is considered to be a key factor in inducing immune tolerance. The effect of TGF-? on DCs is very complex. In this study, we further investigated the effect of TGF-? on inducing immune tolerance of DCs. DCs were differentiated from mice bone marrow cells in the absence or presence of TGF-?. The phenotype as well as function was studied in detail. We found that TGF-? limited the expression of CD40, CD83, CD86 and MHCII in DCs, increased CD45RB and indoleamine 2, 3-dioxygenase (IDO) expression in DCs, promoted IL-10 and limited IL-12 secretion by DCs. Moreover, TGF-? increased the endocytosis ability of DCs and limited the ability of DCs in activating T cells. These results suggest that TGF-? affects the immunity of DCs and enhances their tolerogenicity.
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Increased proportions of Bifidobacterium and the Lactobacillus group and loss of butyrate-producing bacteria in inflammatory bowel disease.
J. Clin. Microbiol.
PUBLISHED: 01-31-2014
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Dysbiosis in the intestinal microbiota of persons with inflammatory bowel disease (IBD) has been described, but there are still varied reports on changes in the abundance of Bifidobacterium and Lactobacillus organisms in patients with IBD. The aim of this investigation was to compare the compositions of mucosa-associated and fecal bacteria in patients with IBD and in healthy controls (HCs). Fecal and biopsy samples from 21 HCs, 21 and 15 Crohn's disease (CD) patients, and 34 and 29 ulcerative colitis (UC) patients, respectively, were analyzed by quantitative real-time PCR targeting the 16S rRNA gene. The bacterial numbers were transformed into relative percentages for statistical analysis. The proportions of bacteria were uniformly distributed along the colon regardless of the disease state. Bifidobacterium was significantly increased in the biopsy specimens of active UC patients compared to those in the HCs (4.6% versus 2.1%, P = 0.001), and the proportion of Bifidobacterium was significantly higher in the biopsy specimens than in the fecal samples in active CD patients (2.7% versus 2.0%, P = 0.012). The Lactobacillus group was significantly increased in the biopsy specimens of active CD patients compared to those in the HCs (3.4% versus 2.3%, P = 0.036). Compared to the HCs, Faecalibacterium prausnitzii was sharply decreased in both the fecal and biopsy specimens of the active CD patients (0.3% versus 14.0%, P < 0.0001 for fecal samples; 0.8% versus 11.4%, P < 0.0001 for biopsy specimens) and the active UC patients (4.3% versus 14.0%, P = 0.001 for fecal samples; 2.8% versus 11.4%, P < 0.0001 for biopsy specimens). In conclusion, Bifidobacterium and the Lactobacillus group were increased in active IBD patients and should be used more cautiously as probiotics during the active phase of IBD. Butyrate-producing bacteria might be important to gut homeostasis.
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Hydrothermal fabrication of hydroxyapatite/chitosan/carbon porous scaffolds for bone tissue engineering.
J. Biomed. Mater. Res. Part B Appl. Biomater.
PUBLISHED: 01-28-2014
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Porous carbon fiber felts (PCFFs) have great applications in orthopedic surgery because of the strong mechanical strength, low density, high stability, and porous structure, but they are biologically inert. To improve their biological properties, we developed, for the first time, the hydroxyapatite (HA)/chitosan/carbon porous scaffolds (HCCPs). HA/chitosan nanohybrid coatings have been fabricated on PCFFs according to the following stages: (i) deposition of chitosan/calcium phosphate precursors on PCFFs; and (ii) hydrothermal transformation of the calcium phosphate precursors in chitosan matrix into HA nanocrystals. The scanning electron microscopy images indicate that PCFFs are uniformly covered with elongated HA nanoplates and chitosan, and the macropores in PCFFs still remain. Interestingly, the calcium-deficient HA crystals exist as plate-like shapes with thickness of 10-18 nm, width of 30-40 nm, and length of 80-120 nm, which are similar to the biological apatite. The HA in HCCPs is similar to the mineral of natural bone in chemical composition, crystallinity, and morphology. As compared with PCFFs, HCCPs exhibit higher in vitro bioactivity and biocompatibility because of the presence of the HA/chitosan nanohybrid coatings. HCCPs not only promote the formation of bone-like apatite in simulated body fluid, but also improve the adhesion, spreading, and proliferation of human bone marrow stromal cells. Hence, HCCPs have great potentials as scaffold materials for bone tissue engineering and implantation.
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Epstein-Barr virus-encoded RNAs as a survival predictor in nasopharyngeal carcinoma.
Chin. Med. J.
PUBLISHED: 01-21-2014
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Epstein-Barr virus (EBV) infection is one of the most important factors of nasopharyngeal carcinoma (NPC) endemic areas. Transcription of EBV-encoded non-polyadenylated RNAs (EBERs) are presented in most of NPC tumors. Exploring EBERs as a prognostic marker for NPC might further be informative about the biology and the progression of the disease. The aim of this study was to analyze the role of EBV latency in the clinical management of nasopharyngeal carcinoma (NPC), by detecting EBERs.
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Sagittal spinopelvic alignment in adolescents associated with Scheuermann's kyphosis: a comparison with normal population.
Eur Spine J
PUBLISHED: 01-20-2014
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Spinopelvic alignment is increasingly considered as a main factor in the energy-efficient posture of the individual in normal and pathological status. However, the spinopelvic characteristics in Scheuermann's kyphosis (SK) are poorly defined in the literature. The purpose of this study was to determine whether differences of the spinopelvic parameters exist between adolescents with SK and age-matched normal controls.
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Stem cell therapies and regenerative medicine in China.
Sci China Life Sci
PUBLISHED: 01-15-2014
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Stem cells are the core of tissue repair and regeneration, and a promising cell source for novel therapies. In recent years, research into stem cell therapies has been particularly exciting in China. The remarkable advancements in basic stem cell research and clinically effective trials have led to fresh insights into regenerative medicine, such as treatments for sweat gland injury after burns, diabetes, and liver injury. High hopes have inspired numerous experimental and clinical trials. At the same time, government investment and policy support of research continues to increase markedly. However, numerous challenges must be overcome before novel stem cell therapies can achieve meaningful clinical outcomes.
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ALK gene copy number gain and its clinical significance in hepatocellular carcinoma.
World J. Gastroenterol.
PUBLISHED: 01-14-2014
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To examine the status and clinical significance of anaplastic lymphoma kinase (ALK) gene alterations in hepatocellular carcinoma (HCC) patients.
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Influence of Pistachios on Performance and Exercise-Induced Inflammation, Oxidative Stress, Immune Dysfunction, and Metabolite Shifts in Cyclists: A Randomized, Crossover Trial.
PLoS ONE
PUBLISHED: 01-01-2014
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Pistachio nut ingestion (3 oz./d, two weeks) was tested for effects on exercise performance and 21-h post-exercise recovery from inflammation, oxidative stress, immune dysfunction, and metabolite shifts.
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A novel catechol-O-methyltransferase variant associated with human disc degeneration.
Int J Med Sci
PUBLISHED: 01-01-2014
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Disc degeneration and its associated low back pain are a major health care concern causing disability with a prominent role in this country's medical, social and economic structure. Low back pain is devastating and influences the quality of life for millions. Low back pain lifetime prevalence approximates 80% with an estimated direct cost burden of $86 billion per year. Back pain patients incur higher costs, greater health care utilization, and greater work loss than patients without back pain.
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Passing through the renal clearance barrier: toward ultrasmall sizes with stable ligands for potential clinical applications.
Int J Nanomedicine
PUBLISHED: 01-01-2014
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The use of nanoparticles holds promise for medical applications, such as X-ray imaging, photothermal therapy and radiotherapy. However, the in vivo toxicity of inorganic nanoparticles raises some concern regarding undesirable side effects which prevent their further medical application. Ultrasmall sub-5.5 nm particles can pass through the barrier for renal clearance, minimizing their toxicity. In this letter we address some recent interesting work regarding in vivo toxicity and renal clearance, and discuss the possible strategy of utilizing ultrasmall nanomaterials. We propose that small hydrodynamic sized nanoclusters can achieve both nontoxic and therapeutic clinical features.
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Oncogene mutational profile in nasopharyngeal carcinoma.
Onco Targets Ther
PUBLISHED: 01-01-2014
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Nasopharyngeal carcinoma (NPC) is a common tumor in Southern China, but the oncogene mutational status of NPC patients has not been clarified. Using time-of-flight mass spectrometry, 238 mutation hotspots in 19 oncogenes were examined in 123 NPC patients. The relationships between mutational status and clinical data were assessed with a ?(2) or Fisher's exact test. Survival analysis was performed using the Kaplan-Meier method with the log-rank test. In 123 patients, 21 (17.1%) NPC tumors were positive for mutations in eight oncogenes: six patients had PIK3CA mutations (4.9%), five NRAS mutations (4.1%), four KIT mutations (3.3%), two PDGFRA mutations (1.6%), two ABL mutations (1.6%), and one with simultaneous mutations in HRAS, EGFR, and BRAF (1%). Patients with mutations were more likely to relapse or develop metastasis than those with wild-type alleles (P=0.019). No differences or correlations were found in other clinical characteristics or in patient survival. No mutations were detected in oncogenes AKT1, AKT2, CDK, ERBB2, FGFR1, FGFR3, FLT3, JAK2, KRAS, MET, and RET. These results demonstrate an association between NPC and mutations in NRAS, KIT, PIK3CA, PDGFRA, and ABL, which are associated with patient relapse and metastasis.
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Knockdown of miR-214 promotes apoptosis and inhibits cell proliferation in nasopharyngeal carcinoma.
PLoS ONE
PUBLISHED: 01-01-2014
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MicroRNA-214 (MiR-214) is aberrantly expressed in several human tumors such as ovarian cancer and breast cancer. However, the role of miR-214 in nasopharyngeal carcinoma (NPC) is still unknown. In this study, we report that miR-214 was overexpressed in NPC cell lines and tissues. Silencing of miR-214 by LNA-antimiR-214 in NPC cells resulted in promoting apoptosis and suppressing cell proliferation in vitro, and suppressed tumor growth in nude mice in vivo. Luciferase reporter assay was performed to identify Bim as a direct target of miR-214. Furthermore, this study showed that low Bim expression in NPC tissues correlated with poor survival of NPC patients. Taken together, our findings suggest that miR-214 plays an important role in NPC carcinogenesis.
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The utility of platelet, mean platelet volume, and red cell distribution width in the diagnosis of active Crohns disease and intestinal tuberculosis.
Saudi Med J
PUBLISHED: 11-21-2013
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To evaluate the diagnostic utility of platelet count (PLT), mean platelet volume (MPV), and red cell distribution width (RDW) in patients with active Crohns disease (CD) and intestinal tuberculosis (ITB).
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Mutation abundance affects the efficacy of EGFR tyrosine kinase inhibitor readministration in non-small-cell lung cancer with acquired resistance.
Med. Oncol.
PUBLISHED: 11-03-2013
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There is no consensus in the salvage treatment for non-small-cell lung cancer (NSCLC) with acquired resistance to primary epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs). Fifty-one consecutive EGFR-mutated NSCLC patients with TKI retreatment after acquired resistance were enrolled in this study. The quantitation of mutation abundance was performed by real-time fluorescent quantitative PCR. The correlation between mutation abundance and outcomes of readministrated TKI was analyzed by survival analysis. Patients with high (H) mutation abundance (24/51) had a significantly (log-rank, P < 0.05) longer (5.27-2.53 months) median progression-free survival (PFS), compared with the low (L) abundance group (27/51), whereas the median overall survival showed no difference (21.00-18.20 months, log-rank P = .403) between the two groups. Objective response and disease control rates in group H and group L regarding the second round TKI treatment were 8.3, 70.8 and 0, 48.1 %, respectively. Groupings with different mutation abundances were significantly associated with PFS under multivariate Cox proportional hazards regression model [hazard ratio (HR) for group H vs. L, 0.527; P = .036]. Mutation abundance affects the efficacy of EGFR-TKIs readministration in NSCLC with acquired resistance. The quantitative mutation abundance of EGFR may be a potential predictor for selecting optimal patients to readministrate EGFR-TKIs after acquired resistance to primary TKI.
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Paracrine factors from mesenchymal stem cells: a proposed therapeutic tool for acute lung injury and acute respiratory distress syndrome.
Int Wound J
PUBLISHED: 10-14-2013
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Despite extensive researches in acute lung injury (ALI) and acute respiratory distress syndrome (ARDS), current pharmacological therapies and respiratory support are still the main methods to treat patients with ALI and ARDS and the effects remain limited. Hence, innovative therapies are needed to decrease the morbidity and mortality. Because of the proven therapeutic effects in other fields, mesenchymal stem cells (MSCs) might be considered as a promising alternative to treat ALI and ARDS. Numerous documents demonstrate that MSCs can exert multiple functions, such as engraftment, differentiation and immunoregulation, but now the key researches are concentrated on paracrine factors secreted by MSCs that can mediate endothelial and epithelial permeability, increase alveolar fluid clearance and other potential mechanisms. This review aimed to review the current researches in terms of the effects of MSCs on ALI and ARDS and to analyse these paracrine factors, as well as to predict the potential directions and challenges of the application in this field.
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Influence of vitamin D mushroom powder supplementation on exercise-induced muscle damage in vitamin D insufficient high school athletes.
J Sports Sci
PUBLISHED: 10-11-2013
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Abstract Incidence of vitamin D deficiency is increasing worldwide. The purpose of this study was to determine if supplementation with vitamin D2 from Portobello mushroom powder would enhance skeletal muscle function and attenuate exercise-induced muscle damage in low vitamin D status high school athletes. Participants were randomised to Portobello mushroom powder (600 IU/d vitamin D2) or placebo for 6 weeks. Participants then completed a 1.5-h exercise session designed to induce skeletal muscle damage. Blood samples and measures of skeletal muscle function were taken pre-supplementation, post-supplementation/pre-exercise and post-exercise. Six weeks supplementation with vitamin D2 increased serum 25(OH)D2 by 9.9-fold and decreased serum 25(OH)D3 by 28%. Changes in skeletal muscle function and circulating markers of skeletal muscle damage did not differ between groups. In conclusion, 600 IU/d vitamin D2 increased 25(OH)D2 with a concomitant decrease in 25(OD)D3, with no effect on muscular function or exercise-induced muscle damage in high school athletes.
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A commercialized dietary supplement alleviates joint pain in community adults: a double-blind, placebo-controlled community trial.
Nutr J
PUBLISHED: 10-08-2013
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The purpose of this study was to assess the effect of 8-weeks ingestion of a commercialized joint pain dietary supplement (InstaflexTM Joint Support, Direct Digital, Charlotte, NC) compared to placebo on joint pain, stiffness, and function in adults with self-reported joint pain. InstaflexTM is a joint pain supplement containing glucosamine sulfate, methylsufonlylmethane (MSM), white willow bark extract (15% salicin), ginger root concentrate, boswella serrata extract (65% boswellic acid), turmeric root extract, cayenne, and hyaluronic acid.
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Synthesis of new potent agonistic analogs of growth hormone-releasing hormone (GHRH) and evaluation of their endocrine and cardiac activities.
Peptides
PUBLISHED: 10-04-2013
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In view of the recent findings of stimulatory effects of GHRH analogs, JI-34, JI-36 and JI-38, on cardiomyocytes, pancreatic islets and wound healing, three series of new analogs of GHRH(1-29) have been synthesized and evaluated biologically in an endeavor to produce more potent compounds. "Agmatine analogs", MR-356 (N-Me-Tyr(1)-JI-38), MR-361(N-Me-Tyr(1), D-Ala(2)-JI-38) and MR-367(N-Me-Tyr(1), D-Ala(2), Asn(8)-JI-38), in which Dat in JI-38 is replaced by N-Me-Tyr(1), showed improved relative potencies on GH release upon subcutaneous administration in vivo and binding in vitro. Modification with N-Me-Tyr(1) and Arg(29)-NHCH3 as in MR-403 (N-Me-Tyr(1), D-Ala(2), Arg(29)-NHCH3- JI-38), MR-406 (N-Me-Tyr(1), Arg(29)-NHCH3- JI-38) and MR-409 (N-Me-Tyr(1), D-Ala(2), Asn(8), Arg(29)-NHCH3- JI-38), and MR-410 (N-Me-Tyr(1), D-Ala(2), Thr(8), Arg(29)-NHCH3- JI-38) resulted in dramatically increased endocrine activities. These appear to be the most potent GHRH agonistic analogs so far developed. Analogs with Apa(30)-NH2 such as MR-326 (N-Me-Tyr(1), D-Ala(2), Arg(29), Apa(30)-NH2-JI-38), and with Gab(30)-NH2, as MR-502 (D-Ala(2), 5F-Phe(6), Ser(28), Arg(29),Gab(30)-NH2-JI-38) also exhibited much higher potency than JI-38 upon i.v. administration. The relationship between the GH-releasing potency and the analog structure is discussed. Fourteen GHRH agonists with the highest endocrine potencies were subjected to cardiologic tests. MR-409 and MR-356 exhibited higher potency than JI-38 in activating myocardial repair in rats with induced myocardial infarction. As the previous class of analogs, exemplified by JI-38, had shown promising results in multiple fields including cardiology, diabetes and wound healing, our new, more potent, GHRH agonists should manifest additional efficacy for possible medical applications.
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Tumor Necrosis Factor-Related Apoptosis Inducing Ligand Gene Polymorphisms are Correlated with Gastric Cancer in Central China.
Pharm. Res.
PUBLISHED: 09-20-2013
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To investigate the association of tumor necrosis factor-related apoptosis inducing ligand (TRAIL) gene polymorphisms with gastric cancer in Chinese Han population in central China.
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Umbilical cord mesenchymal stem cell transplantation ameliorates burn-induced acute kidney injury in rats.
Int J Low Extrem Wounds
PUBLISHED: 09-16-2013
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Excessive systemic inflammation following burns could lead to acute kidney injury (AKI). Mesenchymal stromal cells (MSCs) suppress immune cell responses and have beneficial effects in various inflammatory-related immune disorders. However, autologous MSCs are not vital enough for the treatment because of the severely burned patients deleterious condition. Umbilical cord-derived mesenchymal stem cells (UC-MSCs) could be a suitable substitute cell candidate but no data are available on the therapeutic effectiveness of UC-MSCs transplantation for burn injury and its consequences. In this study, UC-MSCs or ulinastatin was administered intravenously in the rats with burn trauma, and the therapeutic effects of UC-MSCs on the survival of severe burn-induced AKI rats and functional protection of kidney were analyzed. Results showed that UC-MSCs promoted the survival and prevented commitment to apoptosis of resident kidney cells and reduced organ microscopic damage in kidneys after thermal trauma. Thus, our study demonstrates that intravenously delivered UC-MSCs protected the host from death caused by kidney injury subsequent to severe burn, identifying UC-MSCs transplantation may be an attractive candidate for cell-based treatments for burns and induced organ damage.
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Application of (1)h NMR spectroscopy-based metabolomics to sera of tuberculosis patients.
J. Proteome Res.
PUBLISHED: 09-10-2013
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Nuclear magnetic resonance (NMR) spectroscopy is an ideal platform for the metabolic analysis of biofluids due to its high reproducibility, nondestructiveness, nonselectivity in metabolite detection, and the ability to simultaneously quantify multiple classes of metabolites. Tuberculosis (TB) is a chronic wasting inflammatory disease characterized by multisystem involvement, which can cause metabolic derangements in afflicted patients. In this study, we combined multivariate pattern recognition (PR) analytical techniques with (1)H NMR spectroscopy to explore the metabolic profile of sera from TB patients. A total of 77 serum samples obtained from patients with TB (n = 38) and healthy controls (n = 39) were investigated. Orthogonal partial least-squares discriminant analysis (OPLS-DA) was capable of distinguishing TB patients from controls and establishing a TB-specific metabolite profile. A total of 17 metabolites differed significantly in concentration between the two groups. Serum samples from TB patients were characterized by increased concentrations of 1-methylhistidine, acetoacetate, acetone, glutamate, glutamine, isoleucine, lactate, lysine, nicotinate, phenylalanine, pyruvate, and tyrosine, accompanied by reduced concentrations of alanine, formate, glycine, glycerolphosphocholine, and low-density lipoproteins relative to control subjects. Our study reveals the metabolic profile of sera from TB patients and indicates that NMR-based methods can distinguish TB patients from healthy controls. NMR-based metabolomics has the potential to be developed into a novel clinical tool for TB diagnosis or therapeutic monitoring and could contribute to an improved understanding of disease mechanisms.
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Overexpression of the poplar NF-YB7 transcription factor confers drought tolerance and improves water-use efficiency in Arabidopsis.
J. Exp. Bot.
PUBLISHED: 09-04-2013
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Water deficit is a serious environmental factor limiting the growth and productivity of plants worldwide. Improvement of drought tolerance and efficient water use are significant strategies to overcome this dilemma. In this study, a drought-responsive transcription factor, nuclear factor Y subunit B 7 (PdNF-YB7), induced by osmotic stress (PEG6000) and abscisic acid, was isolated from fast-growing poplar clone NE-19 [Populus nigra × (Populus deltoides × Populus nigra)]. Ectopic overexpression of PdNF-YB7 (oxPdB7) in Arabidopsis enhanced drought tolerance and whole-plant and instantaneous leaf water-use efficiency (WUE, the ratio of biomass produced to water consumed). Overexpressing lines had an increase in germination rate and root length and decrease in water loss and displayed higher photosynthetic rate, instantaneous leaf WUE, and leaf water potential to exhibit enhanced drought tolerance under water scarcity. Additionally, overexpression of PdNF-YB7 in Arabidopsis improved whole-plant WUE by increasing carbon assimilation and reducing transpiration with water abundance. These drought-tolerant, higher WUE transgenic Arabidopsis had earlier seedling establishment and higher biomass than controls under normal and drought conditions. In contrast, Arabidopsis mutant nf-yb3 was more sensitive to drought stress with lower WUE. However, complementation analysis indicated that complementary lines (nf-yb3/PdB7) had almost the same drought response and WUE as wild-type Col-0. Taken together, these results suggest that PdNF-YB7 positively confers drought tolerance and improves WUE in Arabidopsis; thus it could potentially be used in breeding drought-tolerant plants with increased production even under water deficiency.
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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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