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Find video protocols related to scientific articles indexed in Pubmed.
A high-throughput metabolomic approach to explore the regulatory effect of mangiferin on metabolic network disturbances of hyperlipidemia rats.
Mol Biosyst
PUBLISHED: 11-20-2014
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This paper was designed to study metabolomic characters of the high-fat diet (HFD)-induced hyperlipidemia and the intervention effects of Mangiferin (MG). In this study, we aimed to investigate the intervention of MG on rats with hyperlipidemia induced by HFD and explore the possible mechanisms of hyperlipidemia. Urine metabolic profiles were analyzed using ultra-performance liquid chromatography/electrospray ionization quadruple time-of-flight mass spectrometry (UPLC-ESI-QTOF-MS) coupled with the principal component analysis (PCA) and partial least squares-discriminate analysis (PLS-DA) models, Heatmap and metabolism pathway analysis. PCA was applied to study the trajectory of the urinary metabolic phenotype of hyperlipidemia rat after administration of MG. The VIP-plot of orthogonal PLS-DA was used for discovering potential biomarkers to clarify the mechanism of MG. Biochemical analyses indicate that MG can alleviate the hyperlipidemia damage. Twenty significantly changed metabolites (potential biomarkers) were found to be reasonable in explaining the action mechanism of MG. The effectiveness of MG on hyperlipidemia is proved using the established metabolomic method and the regulated metabolic pathways involve the TCA cycle, taurine and hypotaurine metabolism, glyoxylate and dicarboxylate metabolism, glycine and serine and threonine metabolism, glycerophospholipid metabolism, primary bile acid biosynthesis etc. The results indicated that MG has a favourable protective effect on HFD-induced hyperlipidemia by adjusting the metabolic disorders. It also suggests that the metabolomic technology is a powerful approach for elucidation of the action mechanisms of MG.
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An Alu Element-Mediated 28.5?kb ?-Thalassemia Deletion Found in a Chinese Family.
Hemoglobin
PUBLISHED: 11-05-2014
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Abstract Over 95.0% of the ?-thalassemia (?-thal) cases in southern China are caused by large deletions involving the ?-globin gene. Here, we describe the molecular characterization of a novel 28.5?kb deletion that eliminated one of the duplicated ?-globin genes in a Chinese family. The deletion breakpoint fragment involved Alu repeat sequences, suggesting a homologous recombination event. Phenotypic analysis on the heterozygous carrier of this deletion revealed that it leads to a very mild phenotype. Because of a 25.0% risk of Hb H (?4) disease in the offspring when in combination with another ?(0)-thal allele, we should not ignore screening the deletion in prenatal diagnosis in order to decrease reproductive risk.
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XRCC1 genetic polymorphism Arg339Gln, Arg194Trp, Arg280His and gastric cancer risk: An evidence based decision.
Cancer Biomark
PUBLISHED: 10-23-2014
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The purpose of this study is to investigate the associations of the x-ray repair cross-complementing 1 gene (XRCC1) single nucleotide polymorphisms (SNPs) Arg194Trp, Arg280His, and Arg399Gln with gastric cancer risk.
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Comparison of ocular modulation transfer function determined by a ray-tracing aberrometer and a double-pass system in early cataract patients.
Chin. Med. J.
PUBLISHED: 10-02-2014
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The evaluation of retinal image quality in cataract eyes has gained importance and the clinical modulation transfer functions (MTF) can obtained by aberrometer and double pass (DP) system. This study aimed to compare MTF derived from a ray tracing aberrometer and a DP system in early cataractous and normal eyes.
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[The clinical significance of typical reflux symptoms in diagnosing gastroesophageal reflux disease].
Zhonghua Nei Ke Za Zhi
PUBLISHED: 09-30-2014
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To explore the clinical significance of typical reflux symptoms in the diagnosis of gastroesophageal reflux disease (GERD).
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ICAM-1 as a molecular target for triple negative breast cancer.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 09-29-2014
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Triple negative breast cancers (TNBCs) have a high mortality rate owing to aggressive proliferation and metastasis and a lack of effective therapeutic options. Herein, we describe the overexpression of intercellular adhesion molecule-1 (ICAM-1) in human TNBC cell lines and tissues, and demonstrate that ICAM-1 is a potential molecular target and biomarker for TNBC therapy and diagnosis. We synthesized ICAM-1 antibody-conjugated iron oxide nanoparticles (ICAM-IONPs) as a magnetic resonance imaging (MRI) probe to evaluate tumor targeting. Quantitative analysis of ICAM-1 surface expression predicted the targeting capability of ICAM-IONPs to TNBC cells. MRI of the TNBC xenograft tumor after systemic administration of ICAM-IONPs, coupled with iron quantification and histology, demonstrated a significant and sustained MRI contrast enhancement and probe accumulation in tumors with ICAM-1 overexpression relative to control. Identification of ICAM-1 as a TNBC target and biomarker may lead to the development of a new strategy and platform for addressing a critical gap in TNBC patient care.
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Thymidine kinase 2 enzyme kinetics elucidate the mechanism of thymidine-induced mitochondrial DNA depletion.
Biochemistry
PUBLISHED: 09-23-2014
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Mitochondrial thymidine kinase 2 (TK2) is a nuclear gene-encoded protein, synthesized in the cytosol and subsequently translocated into the mitochondrial matrix, where it catalyzes the phosphorylation of thymidine (dT) and deoxycytidine (dC). The kinetics of dT phosphorylation exhibits negative cooperativity, but dC phosphorylation follows hyperbolic Michaelis-Menten kinetics. The two substrates compete with each other in that dT is a competitive inhibitor of dC phosphorylation, while dC acts as a noncompetitive inhibitor of dT phosphorylation. In addition, TK2 is feedback inhibited by dTTP and dCTP. TK2 also phosphorylates a number of pyrimidine nucleoside analogues used in antiviral and anticancer therapy and thus plays an important role in mitochondrial toxicities caused by nucleoside analogues. Deficiency in TK2 activity due to genetic alterations causes devastating mitochondrial diseases, which are characterized by mitochondrial DNA (mtDNA) depletion or multiple deletions in the affected tissues. Severe TK2 deficiency is associated with early-onset fatal mitochondrial DNA depletion syndrome, while less severe deficiencies result in late-onset phenotypes. In this review, studies of the enzyme kinetic behavior of TK2 enzyme variants are used to explain the mechanism of mtDNA depletion caused by TK2 mutations, thymidine overload due to thymidine phosphorylase deficiency, and mitochondrial toxicity caused by antiviral thymidine analogues.
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Photosynthesis, chlorophyll fluorescence characteristics, and chlorophyll content of soybean seedlings under combined stress of bisphenol A and cadmium.
Environ. Toxicol. Chem.
PUBLISHED: 09-23-2014
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Bisphenol A (BPA) is ubiquitous in the environment because of its continual application in plastics and the epoxy resin industry. Cadmium (Cd) is a highly toxic heavy metal element mainly used in smelting, electroplating, and plastic and dye manufacturing. Pollution as a result of BPA and Cd exists simultaneously in many agricultural regions. However, little information is available regarding the combined effects of BPA and Cd on plants. The combined effects of BPA and Cd on the photosynthesis, chlorophyll fluorescence, and chlorophyll content of soybean seedlings were investigated using noninvasive technology. Combined treatment with 1.5?mg/L BPA and 0.2?mg/L Cd synergistically improved the net photosynthetic rate (Pn ), initial fluorescence (F0 ), maximal photochemical efficiency (Fv /Fm ), effective quantum yield of photosystem II (?PSII ), photosynthetic electron transport rate (ETR), and chlorophyll content. Combined treatment with 1.5?mg/L BPA and 3.0?mg/L Cd increased the F0 and decreased the Pn , Fv /Fm , ?PSII , and ETR, whereas BPA and Cd exhibited an antagonistic effect. Furthermore, combined treatment with 17.2/50.0?mg/L BPA and 3.0/10.0?mg/L Cd synergistically decreased the Pn , Fv /Fm , ?PSII , ETR, and chlorophyll content, although it increased the F0 . Finally, the effects of BPA and Cd on photosynthesis, chlorophyll fluorescence, and chlorophyll content ceased when BPA stress was stopped. Environ Toxicol Chem 2014;33:2455-2462. © 2014 SETAC.
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Prevalence of nonalcoholic fatty liver disease in mainland of China: a meta-analysis of published studies.
J. Gastroenterol. Hepatol.
PUBLISHED: 09-11-2014
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Nonalcoholic fatty liver disease (NAFLD) is becoming an increasingly important health issue. However, there are no data on the change in prevalence of NAFLD within a population over time, especially in the mainland of China. The goal of this study was to estimate the pooled prevalence of NAFLD in the mainland of China.
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Facile non-hydrothermal synthesis of oligosaccharides coated sub-5 nm magnetic iron oxide nanoparticles with dual MRI contrast enhancement effect.
J Mater Chem B Mater Biol Med
PUBLISHED: 09-03-2014
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Ultrafine sub-5 nm magnetic iron oxide nanoparticles coated with oligosaccharides (SIO) with dual T1-T2 weighted contrast enhancing effect and fast clearance has been developed as magnetic resonance imaging (MRI) contrast agent. Excellent water solubility, biocompatibility and high stability of such sub-5 nm SIO nanoparticles were achieved by using the "in-situ polymerization" coating method, which enables glucose forming oligosaccharides directly on the surface of hydrophobic iron oxide nanocrystals. Reported ultrafine SIO nanoparticles exhibit a longitudinal relaxivity (r1) of 4.1 mM(-1)s(-1) and a r1/r2 ratio of 0.25 at 3 T (clinical field strength), rendering improved T1 or "brighter" contrast enhancement in T1-weighted MRI in addition to typical T2 or "darkening" contrast of conventional iron oxide nanoparticles. Such dual contrast effect can be demonstrated in liver imaging with T2 "darkening" contrast in the liver parenchyma but T1 "bright" contrast in the hepatic vasculature. More importantly, this new class of ultrafine sub-5 nm iron oxide nanoparticles showed much faster body clearance than those with larger sizes, promising better safety for clinical applications.
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Zidovudine induces downregulation of mitochondrial deoxynucleoside kinases: implications for mitochondrial toxicity of antiviral nucleoside analogs.
Antimicrob. Agents Chemother.
PUBLISHED: 09-02-2014
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Mitochondrial thymidine kinase 2 (TK2) and deoxyguanosine kinase (dGK) catalyze the initial phosphorylation of deoxynucleosides in the synthesis of the DNA precursors required for mitochondrial DNA (mtDNA) replication and are essential for mitochondrial function. Antiviral nucleosides are known to cause toxic mitochondrial side effects. Here, we examined the effects of 3'-azido-2',3'-dideoxythymidine (AZT) (zidovudine) on mitochondrial TK2 and dGK levels and found that AZT treatment led to downregulation of mitochondrial TK2 and dGK in U2OS cells, whereas cytosolic deoxycytidine kinase (dCK) and thymidine kinase 1 (TK1) levels were not affected. The AZT effects on mitochondrial TK2 and dGK were similar to those of oxidants (e.g., hydrogen peroxide); therefore, we examined the oxidative effects of AZT. We found a modest increase in cellular reactive oxygen species (ROS) levels in the AZT-treated cells. The addition of uridine to AZT-treated cells reduced ROS levels and protein oxidation and prevented the degradation of mitochondrial TK2 and dGK. In organello studies indicated that the degradation of mitochondrial TK2 and dGK is a mitochondrial event. These results suggest that downregulation of mitochondrial TK2 and dGK may lead to decreased mitochondrial DNA precursor pools and eventually mtDNA depletion, which has significant implications for the regulation of mitochondrial nucleotide biosynthesis and for antiviral therapy using nucleoside analogs.
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Association of KIF21B genetic polymorphisms with ankylosing spondylitis in a Chinese Han population of Shandong Province.
Clin. Rheumatol.
PUBLISHED: 08-23-2014
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Previous studies have found that the kinesin family member (KIF) 21B may contribute to the autoimmune disease process. It has been reported that the KIF21B gene is relevant to the pathogenesis of Crohn's disease (CD) and ulcerative colitis (UC). We hypothesized that KIF21B might be a key gene for ankylosing spondylitis (AS) development. To test this hypothesis, 11 tag single nucleotide polymorphisms (SNPs) covering KIF21B were investigated in 904 Chinese (Han ethnic) patients of Shandong Province with AS and 898 age- and sex-matched controls of the same ethnic origin. The T allele of rs756254 was linked to increased risk of AS (P?=?0.022). The AA genotype of rs296560 and TT and AT genotypes of rs756254 were also relevant with AS (P?=?0.044, P?=?0.033, and P?=?0.033, respectively). Haplotype analysis identified that the KIF21B gene region contains two haplotype blocks of eight and two SNPs, respectively. The haplotype GCGGTAAA in block 1 appeared to reduce the risk of AS (P?=?0.005), while the haplotype AA in block 2 was significantly associated with an increased risk of AS (P?=?0.039). There were no significant differences between the AS patients and the controls in polymorphisms of rs10920091, rs3198583, rs56368827, rs3738255, rs296565, rs12087649, rs12568529, rs7536000, and rs957957. These results indicated that KIF21B was associated with AS in a Chinese population of Shandong Province.
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[Influence of assisted reproduction technologies on genomic imprinting of embryos and offspring].
Zhonghua Yi Xue Yi Chuan Xue Za Zhi
PUBLISHED: 08-15-2014
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Assisted reproduction technologies (ART) include controlled ovarian hyperstimulation, in vitro fertilization-embryo transfer, intracytoplasmic sperm injection, in vitro maturation of oocytes, pre-implantation genetic diagnosis, etc. They have been used for the treatment of impaired fertility but may damage the health of offspring. The ART procedures may alter the epigenetic status of these offspring and DNA methylation may be a crucial mechanism. This paper summarizes epigenetic alterations in ART embryos and offspring, and discusses the risks.
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Heme oxygenase-1 ameliorates dextran sulfate sodium-induced acute murine colitis by regulating Th17/Treg cell balance.
J. Biol. Chem.
PUBLISHED: 08-11-2014
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Inflammatory bowel disease (IBD), including ulcerative colitis and Crohn's disease, is a group of autoimmune diseases characterized by nonspecific inflammation in the gastrointestinal tract. Recent investigations suggest that activation of Th17 cells and/or deficiency of regulatory T cells (Treg) is involved in the pathogenesis of IBD. Heme oxygenase (HO)-1 is a protein with a wide range of anti-inflammatory and immune regulatory function, which exerts significantly protective roles in various T cell-mediated diseases. In this study, we aim to explore the immunological regulation of HO-1 in the dextran sulfate sodium-induced model of experimental murine colitis. BALB/c mice were administered 4% dextran sulfate sodium orally; some mice were intraperitoneally pretreated with HO-1 inducer hemin or HO-1 inhibitor stannum protoporphyrin IX. The results show that hemin enhances the colonic expression of HO-1 and significantly ameliorates the symptoms of colitis with improved histological changes, accompanied by a decreased proportion of Th17 cells and increased number of Tregs in mesenteric lymph node and spleen. Moreover, induction of HO-1 down-regulates retinoic acid-related orphan receptor ?t expression and IL-17A levels, while promoting Treg-related forkhead box p3 (Foxp3) expression and IL-10 levels in colon. Further study in vitro revealed that up-regulated HO-1 switched the naive T cells to Tregs when cultured under a Th17-inducing environment, which involved in IL-6R blockade. Therefore, HO-1 may exhibit anti-inflammatory activity in the murine model of acute experimental colitis via regulating the balance between Th17 and Treg cells, thus providing a possible novel therapeutic target in IBD.
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Different segregation patterns in five carriers due to a pericentric inversion of chromosome 1.
Syst Biol Reprod Med
PUBLISHED: 08-06-2014
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Abstract Pericentric inversion can produce recombinant gametes; however, meiotic segregation studies on the relationship between the frequency of recombinants and the inverted segment size are rare. Triple-color fluorescence in situ hybridization (FISH) was performed to analyze the meiotic behavior in five inv(1) carriers with different breakpoints. Recombination gametes were absent in Patient 1, whereas the percentages of the recombinants in Patients 2, 3, 4, and 5 were of 9.2%, 15.3%, 17.3%, and 40.9%, respectively. A significant difference was present for the frequencies of the recombinant spermatozoa among the five patients (p??0.05). The meiotic segregation of nine inv(1) carriers (including those presented in this paper) is now available. A significant correlation was discovered between the rate of recombination and the proportion of the chromosome implicated in the inversion (R?=?0.9435, p?
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Effects of bisphenol A on chlorophyll synthesis in soybean seedlings.
Environ Sci Pollut Res Int
PUBLISHED: 07-27-2014
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Bisphenol A (BPA), as an emerging environmental pollutant, is potentially harmful to plant growth. Chlorophyll (Chl) is critical in photosynthesis that provides matter and energy for plant growth. How BPA affects the chlorophyll content remains largely unknown. Here, the effects of BPA on Chl synthesis in soybean seedlings were investigated. Exposure to 1.5 mg/L BPA decreased the 5-aminolevulinic acid (ALA) content and increased protoporphyrin IX (Proto IX), magnesium protoporphyrin, and protochlorophyll contents and 5-aminolaevulinic acid dehydratase, porphobilinogen deaminase, uroporphyrinogen III synthase, uroporphyrinogen III decarboxylase, and protoporphyrinogen oxidase activities. Exposure to 17.2 and 50.0 mg/L BPA exerted the opposite effects on these four intermediates and five enzymes. Following the withdrawal of BPA exposure, the aforementioned parameters gradually recovered, except magnesium protoporphyrin content in exposure to 50.0 mg/L BPA. Our findings revealed that exposure to low-concentration BPA increased the Chl content in soybean seedlings through improving Chl synthesis, especially the conversion from ALA to Proto IX, whereas exposure to high-concentration BPA decreased the Chl content through inhibiting Chl synthesis, especially the conversion from ALA to Proto IX. The dual effects of BPA were largely reversed following the withdrawal of BPA exposure.
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Immobilization of Glucose Oxidase on Polydopamine-Functionalized Graphene Oxide.
Appl. Biochem. Biotechnol.
PUBLISHED: 07-17-2014
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In this study, graphene oxide (GO) was modified with dopamine to create a matrix for enzyme immobilization. Dopamine can self-polymerize to get polydopamine (PDA) and coated on GO surface. At the same time, GO was reduced to get PDA/rGO biocomposite. The PDA/rGO may offer adherent surface for enzyme immobilization. Glucose oxidase (GOD), an oxidoreductase, was chosen as model enzyme and can be easily immobilized on PDA/rGO. Experimental results indicated that the thermal and pH stability as well as the storage stability and resistance toward the denaturing agents of GOD were significantly improved after immobilization. The Michaelis constant (K m) of the immobilized GOD was very close to that of the free GOD. This study offers a versatile approach for deposition of biopolymer on GO and provides a way for enzyme immobilization. Hopefully, the immobilized GOD may be further applied for biosensor and biofuel cell applications.
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A two-stage Bayesian method for estimating accuracy and disease prevalence for two dependent dichotomous screening tests when the status of individuals who are negative on both tests is unverified.
BMC Med Res Methodol
PUBLISHED: 07-07-2014
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Estimating the disease prevalence and test accuracy (sensitivity and specificity) for two dependent screening tests when the status of individuals who are negative on both tests is unverified represents a considerable challenge, as the disease rates for individuals negative on both tests are not identifiable without additional assumptions.
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A direct competitive assay-based aptasensor for sensitive determination of tetracycline residue in honey.
Talanta
PUBLISHED: 06-25-2014
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Tetracycline (TC) is a common antibacterial agent used for prevention and control of animal diseases. The increasing concern about TC residue in food demands high-performing analytical techniques for food quality assessment. Biosensors represent a promising tool for food safety analysis as they can fulfill some demand that the conventional methods do not attain. In this study, a novel colorimetric aptasensor was developed for sensitive detection of TC in honey. The aptasensor was based on a modified direct competitive enzyme-linked aptamer assay (dc-ELAA) scheme utilizing a 76 mer single-stranded DNA (ssDNA) aptamer selected by Systematic Evolution of Ligands by Exponential Enrichment (SELEX). The optimized aptasensor showed a good limit of detection (LOD of 0.0978 ng/mL), a wide linear range (0.1-1000 ng/mL) toward TC in honey, with good recoveries (92.09-109.7%) in TC-spiked honey, and was compared with an indirect competitive assay-based aptasensor and validated with a standard ELISA. The biosensor based on dc-ELAA with good limit of detection and simplicity can be applied for high-throughput detection of TC in food.
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Mycoplasma pneumoniae thymidine phosphorylase.
Nucleosides Nucleotides Nucleic Acids
PUBLISHED: 06-19-2014
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Mycoplasma pneumoniae (Mpn) is a human pathogen causing acute respiratory diseases and accounts for approximately 30% cases of community-acquired pneumonia. Co-infection with Mycoplasmas compromises the efficacy of anticancer and antiviral nucleoside analog-based drugs due to the presence of Mycoplasma thymidine phosphorylase (TP). In this study, a TP-deficient strain of Mpn was generated in order to study the effect of Mpn TP in the metabolism of nucleoside analogs. Deficiency in TP activity led to increased uptake and incorporation of radiolabeled deoxyuridine and uracil but thymidine uptake was not affected. The activities of enzymes in the salvage of thymidine and deoxyuridine, e.g., thymidine kinase and uracil phosphoribosyltransferase were upregulated in the TP-deficient mutant, which may explain the increased uptake of deoxyuridine and uracil. Thirty FDA-approved anticancer and antiviral nucleoside and nucleobase analogs were used to screen their inhibitory activity toward the TP mutant and the wild type strain. Seven analogs were found to inhibit strongly the growth of both wild type and TP mutant. Differences in the inhibitory effect of several purine analogs between the two strains were observed. Further study is needed in order to understand the mechanism of inhibition caused by these analogs. Our results indicated that TP is not an essential gene for Mpn survival and TP deficiency affects other enzymes in Mpn nucleotide metabolism, and suggested that Mycoplasma nucleotide biosynthesis pathway enzymes are potential targets for future development of antibiotics.
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Mitochondrial thymidine kinase 2 but not deoxyguanosine kinase is up-regulated during the stationary growth phase of cultured cells.
Nucleosides Nucleotides Nucleic Acids
PUBLISHED: 06-19-2014
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Mitochondrial thymidine kinase 2 (TK2) and deoxyguanosine kinase (dGK) catalyze the initial phosphorylation of pyrimidine and purine deoxyribonucleosides, and are essential for maintaining mitochondrial dNTP pools for mitochondrial DNA replication. Here the expression of mitochondrial TK2 and dGK in relation to cell growth phases in cultured cells was investigated. TK2 and dGK protein levels in isolated mitochondria and TK2 activity in total cell extracts from U2OS and TK1 deficient L929 cells were determined. We found that TK2 levels were negatively correlated with cell growth rates and there was an exponential increase in TK2 levels in cells entering stationary phase. The expression of dGK did not change and appeared to be constitutive.
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Down-regulation of mitochondrial thymidine kinase 2 and deoxyguanosine kinase by didanosine: implication for mitochondrial toxicities of anti-HIV nucleoside analogs.
Biochem. Biophys. Res. Commun.
PUBLISHED: 06-16-2014
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Mitochondrial thymidine kinase 2 (TK2) and deoxyguanosine kinase (dGK) catalyze the initial rate limiting phosphorylation of deoxynucleosides and are essential enzymes for mitochondrial function. Chemotherapy using nucleoside analogs is often associated with mitochondrial toxicities. Here we showed that incubation of U2OS cells with didanosine (ddI, 2',3'-dideoxyinosine), a purine nucleoside analog used in the highly active antiretroviral therapy (HAART), led to selective degradation of both mitochondrial TK2 and dGK while the cytosolic deoxycytidine kinase (dCK) and thymidine kinase 1 (TK1) were not affected. Addition of guanosine to the ddI-treated cells prevented the degradation of mitochondrial TK2 and dGK. The levels of intracellular reactive oxygen species and protein oxidation in ddI-treated and control cells were also measured. The results suggest that down-regulation of mitochondrial TK2 and dGK may be a mechanism of mitochondrial toxicity caused by antiviral and anticancer nucleoside analogs.
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Molecular weight degradation and rheological properties of schizophyllan under ultrasonic treatment.
Ultrason Sonochem
PUBLISHED: 06-08-2014
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Molecular weight degradation effects of schizophyllan (SPG) under ultrasonic treatments were investigated in this study. The degradation product was treated by alcohol fractional precipitation technology, and the molecular weight and rheological properties of ultrasonic-treated SPG (USPG) fractions were evaluated. Average molecular weight of SPG decreased significantly after ultrasonic treatments, and degradation product had more narrow distribution of molecular weight. The molecular weight degradation kinetics of SPG is adequately described by a second-order reaction. USPG fractions with different molecular weight were obtained by fractional precipitation for final alcohol concentration fractions 0-40%, 40-60% and 60-80%, respectively. USPG fractions had near-Newtonian flow behaviors, and USPG80% exhibited viscous responses over the entire accessible frequency range. Therefore, ultrasonic treatment is a viable modification technology for SPG and other polymer materials with high molecular weight.
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Prospective multi-region study on primary antibiotic resistance of Helicobacter pylori strains isolated from Chinese patients.
Dig Liver Dis
PUBLISHED: 06-04-2014
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Large-scale multi-region studies are urgently needed to provide comprehensive and up-to-date information on the antibiotic resistance of Helicobacter pylori that is critical for selecting the most optimal eradication regimens.
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Effects of dietary wheat bran arabinoxylans on cholesterol metabolism of hypercholesterolemic hamsters.
Carbohydr Polym
PUBLISHED: 06-02-2014
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The aim of the present study is to investigate the effects of dietary wheat bran arabinoxylans (AXs) on cholesterol metabolism in hypercholesterolemic hamsters. The hamsters were divided into 3 groups and fed the experimental diets containing AXs or oat ?-glucan at a dose of 5 g/kg for 30 days. As the results, the AXs lowered plasma total cholesterol and LDL-cholesterol concentrations, and increased excretions of total lipids, cholesterol and bile acids, as well as oat ?-glucan. The AXs reduced the activity of 3-hydroxy-3-methyl glutaryl-coenzyme A (HMG-CoA) reductase, and increased the activity of cholesterol 7-? hydroxylase (CYP7A1) in liver. Moreover, the AXs increased propionate and the total short-chain fatty acids (SCFAs) concentrations. These results indicated that dietary AXs reduced the plasma total cholesterol and LDL-cholesterol concentrations by promoting the excretion of fecal lipids, regulating the activities of HMG-CoA reductase and CYP7A1, and increasing colonic SCFAs in hamsters.
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Up-regulation of VEGF by retinoic acid during hyperoxia prevents retinal neovascularization and retinopathy.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 05-29-2014
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Retinopathy of prematurity (ROP) is directly associated with abnormal expression of retinal vascular endothelial growth factor (VEGF) in premature neonates. This study was to investigate whether the systemic administration of retinoic acid (RA) regulates retinal VEGF expression and prevents retinal neovascularization and retinopathy in the oxygen-induced retinopathy (OIR) mouse model.
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Immobilized lipase from Candida sp. 99-125 on hydrophobic silicate: characterization and applications.
Appl. Biochem. Biotechnol.
PUBLISHED: 05-16-2014
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Lipase Candida sp. 99-125 has been proved to be quite effective in catalyzing organic synthesis reactions and is much cheaper than commercial lipases. Mesoporous silicates are attractive materials for the immobilization of enzymes due to their unique structures. The present research designed a hydrophobic silicate with uniform pore size suitable for the comfort of lipase Candida sp. 99-125 for improving its activity and stability. The resulting immobilized lipase (LP@PMO) by adsorption was employed to catalyze hydrolysis, esterification, and transesterification reactions, and the performances were compared with the lipase immobilized on hydrophilic silicate (LP@PMS) and native lipase. The LP@PMO showed as high activity as that of native lipase in hydrolysis and much increased catalytic activity and reusability in the reactions for biodiesel production. Besides, LP@PMO also possessed better organic stability. Such results demonstrate that immobilization of lipase onto hydrophobic supports is a promising strategy to fabricate highly active and stable biocatalysts for applications.
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Functional connectivity changes between parietal and prefrontal cortices in primary insomnia patients: evidence from resting-state fMRI.
Eur. J. Med. Res.
PUBLISHED: 05-15-2014
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Primary insomnia can severely impair daytime function by disrupting attention and working memory and imposes a danger to self and others by increasing the risk of accidents. We speculated that the neurobiological changes impeding working memory in primary insomnia patients would be revealed by resting-state functional MRI (R-fMRI), which estimates the strength of cortical pathways by measuring local and regional correlations in blood oxygen level dependent (BOLD) signs independent of specific task demands.
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[Preparation of the recombinant lentiviral expression vector targeting human Wnt5a gene and its inhibitory effect on melanoma cell invasion].
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi
PUBLISHED: 05-07-2014
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To construct a recombinant lentiviral vector expressing small-hairpin RNA (shRNA) targeting human Wnt5a gene and investigate its silencing effect on WM793B human melanoma invasion.
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[Antibiotic resistance of Helicobacter pylori in children and macrolide-resistant genotypes in Helicobacter pylori].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 04-26-2014
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To explore the antibiotic resistance of Helicobacter pylori (H.pylori ) in children and identify 23 S rRNA gene mutations in macrolide-resistant strains.
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Relationship of Helicobacter pylori eradication with gastric cancer and gastric mucosal histological changes: a 10-year follow-up study.
Chin. Med. J.
PUBLISHED: 04-26-2014
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Helicobacter pylori (Hp) is a common and potentially curable cause of gastric mucosa lesion. This study investigated the relationship of Hp infection with histological changes in gastric mucosa and gastric cancer in Hp-positive patients compared with Hp-eradication patients followed up for ten years.
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Likelihood ratio tests in rare variant detection for continuous phenotypes.
Ann. Hum. Genet.
PUBLISHED: 04-22-2014
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It is believed that rare variants play an important role in human phenotypes; however, the detection of rare variants is extremely challenging due to their very low minor allele frequency. In this paper, the likelihood ratio test (LRT) and restricted likelihood ratio test (ReLRT) are proposed to test the association of rare variants based on the linear mixed effects model, where a group of rare variants are treated as random effects. Like the sequence kernel association test (SKAT), a state-of-the-art method for rare variant detection, LRT and ReLRT can effectively overcome the problem of directionality of effect inherent in the burden test in practice. By taking full advantage of the spectral decomposition, exact finite sample null distributions for LRT and ReLRT are obtained by simulation. We perform extensive numerical studies to evaluate the performance of LRT and ReLRT, and compare to the burden test, SKAT and SKAT-O. The simulations have shown that LRT and ReLRT can correctly control the type I error, and the controls are robust to the weights chosen and the number of rare variants under study. LRT and ReLRT behave similarly to the burden test when all the causal rare variants share the same direction of effect, and outperform SKAT across various situations. When both positive and negative effects exist, LRT and ReLRT suffer from few power reductions compared to the other two competing methods; under this case, an additional finding from our simulations is that SKAT-O is no longer the optimal test, and its power is even lower than that of SKAT. The exome sequencing SNP data from Genetic Analysis Workshop 17 were employed to illustrate the proposed methods, and interesting results are described.
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Age distribution of various corneal diseases in China by histopathological examination of 3112 surgical specimens.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 04-12-2014
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To analyze the age distribution of corneal disease in China by histopathological examination.
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Effects of dietary hull-less barley ?-glucan on the cholesterol metabolism of hypercholesterolemic hamsters.
Food Chem
PUBLISHED: 04-08-2014
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The aim of the present study is to investigate the hypocholesterolemic effects of dietary hull-less barley ?-glucan (HBG) on cholesterol metabolism in hamsters which were fed a hypercholesterolemic diet. The hamsters were divided into 3 groups and fed experimental diets, containing 5‰ HBG or 5‰ oat ?-glucan (OG), for 30days. The HBG, as well as OG, lowered the concentration of plasma LDL-cholesterol significantly. The excretion of total lipids and cholesterol in feces were increased in HBG and OG groups compared with the control group. The activity of 3-hydroxy-3-methyl glutaryl-coenzyme A (HMG-CoA) reductase in liver was reduced significantly in the HBG group compared with the control and OG groups. The activity of cholesterol 7-? hydroxylase (CYP7A1) in the liver, in the HBG and OG groups, was significantly increased compared with the control group. The concentrations of acetate, propionate and total short chain fatty acids (SCFAs) were not significantly different between the HBG and control groups. These results indicate that dietary HBG reduces the concentration of plasma LDL cholesterol by promoting the excretion of fecal lipids, and regulating the activities of HMG-CoA reductase and CYP7A1 in hypercholesterolemic hamsters.
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Nitidine chloride inhibits hepatic cancer growth via modulation of multiple signaling pathways.
BMC Cancer
PUBLISHED: 03-31-2014
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The development of hepatic cancer is tightly regulated by multiple intracellular signaling pathways. Therefore, most currently-used anti-tumor agents, which typically target single intracellular pathway, might not always be therapeutically effective. Additionally, long-term use of these agents probably generates drug resistance and unacceptable adverse effects. These problems increase the necessity for the development of new chemotherapeutic approaches. Nitidine chloride (NC), a natural benzophenanthridine alkaloid, has been shown to inhibit cancer growth via induction of cell apoptosis and suppression of cancer angiogenesis. But the precise mechanisms of its tumorcidal activity are not well understood.
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MicroRNA-21 stimulates gastric cancer growth and invasion by inhibiting the tumor suppressor effects of programmed cell death protein 4 and phosphatase and tensin homolog.
J BUON
PUBLISHED: 03-25-2014
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MicroRNA-21 (miR-21) is abnormally expressed in many solid cancers, such as gastric adenocarcinoma, and regulates some targets involved in cancer initiation and progression. In this study, we investigated the function of miR-21 in two gastric cancer cell lines, as well as its potential targeting of the tumor suppressor genes phosphatase and tensin homolog (PTEN) and programmed cell death protein 4 (PDCD4).
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[Protective effect of necrostatin-1 on the liver of rats with trauma induced hemorrhagic shock].
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue
PUBLISHED: 03-22-2014
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To investigate the effects of necrostatin-1( Nec-1) on the liver of rats with trauma induced hemorrhagic shock.
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A comparative study of sequential therapy and standard triple therapy for Helicobacter pylori infection: a randomized multicenter trial.
Am. J. Gastroenterol.
PUBLISHED: 03-18-2014
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Studies conducted in large populations of patients and providing full information on Helicobacter pylori (H. pylori) antibiotic resistance are needed to determine the efficacy of sequential therapy (SQT) against this pathogen. This study compared eradication rates with SQT and standard triple therapy (STT), and evaluated the impact of antibiotic resistance on outcomes.
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Hepatitis C virus NS5A hijacks ARFGAP1 to maintain a phosphatidylinositol 4-phosphate-enriched microenvironment.
J. Virol.
PUBLISHED: 03-12-2014
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Phosphatidylinositol 4-phosphate (PI4P) is well known to be upregulated during hepatitis C virus (HCV) replication. The role of PI4 kinases in HCV has been extensively investigated. Whether the PI4P phosphatase Sac1 is altered by HCV remains unclear. Here, we identified ARFGAP1 to be a novel host factor for HCV replication. We further show that Sac1 interacts with ARFGAP1 and inhibits HCV replication. The elevation of PI4P induced by HCV NS5A is abrogated when the coatomer protein I (COPI) pathway is inhibited. We also found an interaction between NS5A and ARFGAP1. Furthermore, we identified a conserved cluster of positively charged amino acids in NS5A critical for interaction between NS5A and ARFGAP1, induction of PI4P, and HCV replication. Our data demonstrate that ARFGAP1 is a host factor for HCV RNA replication. ARFGAP1 is hijacked by HCV NS5A to remove COPI cargo Sac1 from the site of HCV replication to maintain high levels of PI4P. Our findings provide an additional mechanism by which HCV enhances formation of a PI4P-rich environment.
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Novel Technique to Narrow the Wide Midface in Asians.
J. Oral Maxillofac. Surg.
PUBLISHED: 03-03-2014
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To develop a novel technique for narrowing the wide midface in Asians using virtual surgical planning (VSP) and 2-bent plate fixation.
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GPC5, a tumor suppressor, is regulated by miR-620 in lung adenocarcinoma.
Mol Med Rep
PUBLISHED: 02-27-2014
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In the current study, a proportion of lung adenocarcinoma was shown to reduce GPC5 expression in the absence of transcriptional silencing of the tumor suppressor gene, GPC5, by aberrant methylation of CpG islands. It was hypothesized that the loss of GPC5 expression is associated with upregulation of miR?620 in human lung adenocarcinoma tissue compared with the matched normal lung tissue. The downregulation of GPC5 in lung adenocarcinoma cell lines is regulated by miR?620 through binding of the 3'?untranslated region. Furthermore, blockage of miR?620 inhibited the proliferation, migration and invasion of lung adenocarcinoma cells by directly regulating GPC5, and GPC5 knockdown eliminates this phenotype. These results provided a novel insight into the mechanism of miRNA regulation in lung adenocarcinoma.
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The contribution of mitochondrial thymidylate synthesis in preventing the nuclear genome stress.
Nucleic Acids Res.
PUBLISHED: 02-21-2014
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In quiescent fibroblasts, the expression levels of cytosolic enzymes for thymidine triphosphate (dTTP) synthesis are down-regulated, causing a marked reduction in the dTTP pool. In this study, we provide evidence that mitochondrial thymidylate synthesis via thymidine kinase 2 (TK2) is a limiting factor for the repair of ultraviolet (UV) damage in the nuclear compartment in quiescent fibroblasts. We found that TK2 deficiency causes secondary DNA double-strand breaks formation in the nuclear genome of quiescent cells at the late stage of recovery from UV damage. Despite slower repair of quiescent fibroblast deficient in TK2, DNA damage signals eventually disappeared, and these cells were capable of re-entering the S phase after serum stimulation. However, these cells displayed severe genome stress as revealed by the dramatic increase in 53BP1 nuclear body in the G1 phase of the successive cell cycle. Here, we conclude that mitochondrial thymidylate synthesis via TK2 plays a role in facilitating the quality repair of UV damage for the maintenance of genome integrity in the cells that are temporarily arrested in the quiescent state.
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The role of environmental factors in the spatial distribution of Japanese encephalitis in mainland China.
Environ Int
PUBLISHED: 02-14-2014
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Japanese encephalitis (JE) is the most common cause of viral encephalitis and an important public health concern in the Asia-Pacific region, particularly in China where 50% of global cases are notified. To explore the association between environmental factors and human JE cases and identify the high risk areas for JE transmission in China, we used annual notified data on JE cases at the center of administrative township and environmental variables with a pixel resolution of 1km×1km from 2005 to 2011 to construct models using ecological niche modeling (ENM) approaches based on maximum entropy. These models were then validated by overlaying reported human JE case localities from 2006 to 2012 onto each prediction map. ENMs had good discriminatory ability with the area under the curve (AUC) of the receiver operating curve (ROC) of 0.82-0.91, and low extrinsic omission rate of 5.44-7.42%. Resulting maps showed JE being presented extensively throughout southwestern and central China, with local spatial variations in probability influenced by minimum temperatures, human population density, mean temperatures, and elevation, with contribution of 17.94%-38.37%, 15.47%-21.82%, 3.86%-21.22%, and 12.05%-16.02%, respectively. Approximately 60% of JE cases occurred in predicted high risk areas, which covered less than 6% of areas in mainland China. Our findings will help inform optimal geographical allocation of the limited resources available for JE prevention and control in China, find hidden high-risk areas, and increase the effectiveness of public health interventions against JE transmission.
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Preparation of robust biocatalyst based on cross-linked enzyme aggregates entrapped in three-dimensionally ordered macroporous silica.
ACS Appl Mater Interfaces
PUBLISHED: 02-11-2014
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With the aim to provide a highly stable and active biocatalyst, cross-linked enzyme aggregates (CLEAs) of lipase Candida sp. 99-125 were prepared in three-dimensionally ordered macroporous silica materials (CLEAs-LP@3DOM-SiO2). Lipase Candida sp. 99-125 was first precipitated in the pores of 3DOM SiO2 (named EAs-LP@3DOM-SiO2), and further cross-linked by glutaraldehyde to form CLEAs-LP@3DOM-SiO2. Saturated ammonium sulfate was used as a precipitant and glutaraldehyde with a concentration of 0.25% (w/w) was employed as a cross-linker. Compared with EAs-LP@3DOM-SiO2 and native lipase, CLEAs-LP@3DOM-SiO2 exhibited excellent thermal and mechanical stability, and could maintain more than 85% of initial activity after 16 days of shaking in organic and aqueous phase. When CLEAs-LP@3DOM-SiO2 was applied in esterification and transesterification reactions, improved activity and reusability were achieved. This method can be used for the immobilization of other enzymes of interest.
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Development of an indirect competitive assay-based aptasensor for highly sensitive detection of tetracycline residue in honey.
Biosens Bioelectron
PUBLISHED: 02-08-2014
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Tetracycline (TC) is widely used for prevention and control of animal diseases for its broad spectrum antimicrobial activity and low cost, but its abuse can seriously affect human health and may result in trade loss. Thus there is an imperative need to develop high-performing analytical technique for TC detection. In this study, we developed a biosensor based on an indirect competitive enzyme-linked aptamer assay (ic-ELAA). A 76mer single-stranded DNA (ssDNA) aptamer, selected by Systematic Evolution of Ligands by Exponential Enrichment (SELEX), was applied for the recognition and detection of TC in honey. The limit of detection was 9.6×10(-3) ng/mL with a linear working range from 0.01 to 100 ng/mL toward TC in honey, and a mean recovery rate of 93.23% in TC-spiked honey was obtained. This aptasensor can be applied to detect TC residue in food with high sensitivity and simplicity, and it is prospective to develop useful ELAA Kits for TC determination in food.
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Weight loss, inflammatory markers, and improvements of iron status in overweight and obese children.
J. Pediatr.
PUBLISHED: 02-08-2014
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To assess the effect of a weight-loss program on improving iron status in overweight and obese school-aged children.
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Assisted reproductive technologies impair the expression and methylation of insulin-induced gene 1 and sterol regulatory element-binding factor 1 in the fetus and placenta.
Fertil. Steril.
PUBLISHED: 01-30-2014
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To evaluate the cholesterol metabolism linked to assisted reproductive technology (ART) by analyzing the expression levels and DNA methylation patterns of the insulin-induced gene (INSIG), sterol regulatory element-binding protein (SREBP), and SREBP cleavage-activating protein in the fetus and placenta.
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Human bile contains microRNA-laden extracellular vesicles that can be used for cholangiocarcinoma diagnosis.
Hepatology
PUBLISHED: 01-29-2014
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Cholangiocarcinoma (CCA) presents significant diagnostic challenges, resulting in late patient diagnosis and poor survival rates. Primary sclerosing cholangitis (PSC) patients pose a particularly difficult clinical dilemma because they harbor chronic biliary strictures that are difficult to distinguish from CCA. MicroRNAs (miRs) have recently emerged as a valuable class of diagnostic markers; however, thus far, neither extracellular vesicles (EVs) nor miRs within EVs have been investigated in human bile. We aimed to comprehensively characterize human biliary EVs, including their miR content. We have established the presence of extracellular vesicles in human bile. In addition, we have demonstrated that human biliary EVs contain abundant miR species, which are stable and therefore amenable to the development of disease marker panels. Furthermore, we have characterized the protein content, size, numbers, and size distribution of human biliary EVs. Utilizing multivariate organization of combinatorial alterations (MOCA), we defined a novel biliary vesicle miR-based panel for CCA diagnosis that demonstrated a sensitivity of 67% and specificity of 96%. Importantly, our control group contained 13 PSC patients, 16 with biliary obstruction of varying etiologies (including benign biliary stricture, papillary stenosis, choledocholithiasis, extrinsic compression from pancreatic cysts, and cholangitis), and 3 with bile leak syndromes. Clinically, these types of patients present with a biliary obstructive clinical picture that could be confused with CCA.
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Helicobacter pylori infection: an overview in 2013, focus on therapy.
Chin. Med. J.
PUBLISHED: 01-24-2014
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This article aimed to review the incidence of Helicobacter pylori (H. pylori) infection and its therapy.
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Novel decorin mutation in a Chinese family with congenital stromal corneal dystrophy.
Cornea
PUBLISHED: 01-14-2014
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The aim of this study was to characterize the congenital stromal corneal dystrophy (CSCD) pathological and clinical phenotype in a Chinese family with a novel mutation of decorin and its possible molecular pathogenesis.
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Immobilization of horseradish peroxidase in phospholipid-templated titania and its applications in phenolic compounds and dye removal.
Enzyme Microb. Technol.
PUBLISHED: 01-14-2014
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In this study, horseradish peroxidase (HRP) was encapsulated in phospholipid-templated titania particles through the biomimetic titanification process and used for the treatment of wastewater polluted with phenolic compounds and dye. The encapsulated HRP exhibited improved thermal stability, a wide range of pH stability and high tolerance against inactivating agents. It was observed an increase in Km value for the encapsulated HRP (8.21 mM) when compared with its free counterpart. For practical applications in the removal of phenolic compounds and dye by the encapsulated HRP, the removal efficiency for phenol, 2-chlorophenol, Direct Black-38 were 92.99%, 87.97%, and 79.72%, respectively, in the first treatment cycle. Additionally, the encapsulated HRP showed better removal efficiency than free HRP and a moderately good capability of reutilization.
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Clinical characteristics of craniomaxillofacial fibrous dysplasia.
J Craniomaxillofac Surg
PUBLISHED: 01-12-2014
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The clinical characteristics of craniomaxillofacial fibrous dysplasia (FD) have not been clearly identified. The objective of this meta-analysis is to assess the predominance of the monostotic form of FD using an evidence-based review. Furthermore, we examined the laterality and sex dominance of FD in patients from international study populations.
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Immunogenicity of the capsid precursor and a nine-amino-acid site-directed mutant of the 3C protease of foot-and-mouth disease virus coexpressed by a recombinant goatpox virus.
Arch. Virol.
PUBLISHED: 01-11-2014
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The myristoylated capsid precursor mP1-2A of foot-and-mouth disease virus (FMDV), when expressed in mammalian cells and processed by the FMDV 3C protease, can self-assemble into virus-like particles (VLPs). In the present study, nine amino acids of the 3C protease were replaced by site-directed mutagenesis to create a mutant 3C protease, 9m3C. To coexpress mP1-2A and 9m3C and test the resulting proteolytic processing and VLP assembly, two recombinant goatpox viruses (rGTPVs) were constructed by the insertion of two coding regions, one for mP1-2A and the other for either 9m3C (rGTPV-mP1-2A-9m3C) or Theileria protective antigen (TPA) as a control (rGTPV-mP1-2A-TPA). The two exogenous genes were inserted into an intergenic region between loci gp_24 and gp_24.5 of the rGTPV genome. Western blotting of cells infected with rGTPV-mP1-2A-9m3C showed that proteins VP0, VP1, and VP3 from the mP1-2A processed by the 9m3C protease could be detected by polyclonal FMDV sera. As observed by electron microscopy, the infected cells produced VLPs with a diameter of about 25 ± 2 nm. Titers of neutralizing antibody against FMDV were significantly higher in mice inoculated with rGTPV-mP1-2A-9m3C, which expresses the 9m3C protease together with mP1-2A, than mice inoculated with the control rGTPV-mP1-2A-TPA, which does not express the protease. An ovine immunization test determined that sheep inoculated intramuscularly with rGTPV-mP1-2A-9m3C produced FMDV-specific neutralizing antibody, but its titers did not meet the requirement of the World Organization for Animal Health. The result indicates that further modifications of rGTPV-mP1-2A-9m3C are necessary to produce an effective vaccine.
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Co-aggregation of laccase and nature egg white: a simple method to prepare stable and recyclable biocatalyst.
Appl. Biochem. Biotechnol.
PUBLISHED: 01-08-2014
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Cross-linked enzyme aggregates (CLEAs) are a versatile and effective method for enzyme immobilization, which is exquisitely simple and amenable to rapid optimization. In this study, nature egg white, which is low cost, easily available, and nontoxic, was used as protein feeder to replace traditional protein feeder (bovine serum albumin, etc.) in the preparation of laccase CLEAs (CLEAs-egg). The effects of the various parameters--nature of the precipitant, temperature, glutaraldehyde concentration, and cross-linking time--on the activity recovery of the resulting CLEAs were studied. The laccase CLEAs-egg exhibited increased stability compared to the free and the laccase CLEAs without protein feeder. The thermal stability of CLEAs-egg was improved and showed 1.3- and 1.8-fold increase in activity at 40 and 60 °C after 5 h incubation, respectively. The stability of CLEAs-egg against denaturants (urea and GndHCl) and protease (trypsin) was also improved. Laccase CLEAs-egg was also demonstrated to be an active and stable biocatalyst in the removal of chlorophenol. After 30 h, 83.6 and 91.5% of 4-chlorophenol and 2,4-dichlorophenol can be removed.
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Single-step assembly of polymer-lipid hybrid nanoparticles for mitomycin C delivery.
Nanoscale Res Lett
PUBLISHED: 01-01-2014
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Mitomycin C is one of the most effective chemotherapeutic agents for a wide spectrum of cancers, but its clinical use is still hindered by the mitomycin C (MMC) delivery systems. In this study, the MMC-loaded polymer-lipid hybrid nanoparticles (NPs) were prepared by a single-step assembly (ACS Nano 2012, 6:4955 to 4965) of MMC-soybean phosphatidyhlcholine (SPC) complex (Mol. Pharmaceutics 2013, 10:90 to 101) and biodegradable polylactic acid (PLA) polymers for intravenous MMC delivery. The advantage of the MMC-SPC complex on the polymer-lipid hybrid NPs was that MMC-SPC was used as a structural element to offer the integrity of the hybrid NPs, served as a drug preparation to increase the effectiveness and safety and control the release of MMC, and acted as an emulsifier to facilitate and stabilize the formation. Compared to the PLA NPs/MMC, the PLA NPs/MMC-SPC showed a significant accumulation of MMC in the nuclei as the action site of MMC. The PLA NPs/MMC-SPC also exhibited a significantly higher anticancer effect compared to the PLA NPs/MMC or free MMC injection in vitro and in vivo. These results suggested that the MMC-loaded polymer-lipid hybrid NPs might be useful and efficient drug delivery systems for widening the therapeutic window of MMC and bringing the clinical use of MMC one step closer to reality.
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Hepatic carboxylesterase 1 is induced by glucose and regulates postprandial glucose levels.
PLoS ONE
PUBLISHED: 01-01-2014
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Metabolic syndrome, characterized by obesity, hyperglycemia, dyslipidemia and hypertension, increases the risks for cardiovascular disease, diabetes and stroke. Carboxylesterase 1 (CES1) is an enzyme that hydrolyzes triglycerides and cholesterol esters, and is important for lipid metabolism. Our previous data show that over-expression of mouse hepatic CES1 lowers plasma glucose levels and improves insulin sensitivity in diabetic ob/ob mice. In the present study, we determined the physiological role of hepatic CES1 in glucose homeostasis. Hepatic CES1 expression was reduced by fasting but increased in diabetic mice. Treatment of mice with glucose induced hepatic CES1 expression. Consistent with the in vivo study, glucose stimulated CES1 promoter activity and increased acetylation of histone 3 and histone 4 in the CES1 chromatin. Knockdown of ATP-citrate lyase (ACL), an enzyme that regulates histone acetylation, abolished glucose-mediated histone acetylation in the CES1 chromatin and glucose-induced hepatic CES1 expression. Finally, knockdown of hepatic CES1 significantly increased postprandial blood glucose levels. In conclusion, the present study uncovers a novel glucose-CES1-glucose pathway which may play an important role in regulating postprandial blood glucose levels.
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Effect of sperm DNA fragmentation on clinical outcome of frozen-thawed embryo transfer and on blastocyst formation.
PLoS ONE
PUBLISHED: 01-01-2014
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During the last decades, many studies have shown the possible influence of sperm DNA fragmentation on assisted reproductive technique outcomes. However, little is known about the impact of sperm DNA fragmentation on the clinical outcome of frozen-thawed embryo transfer (FET) from cycles of conventional in vitro fertilization (IVF) and intra-cytoplasmic sperm injection (ICSI). In the present study, the relationship between sperm DNA fragmentation (SDF) and FET clinical outcomes in IVF and ICSI cycles was analyzed. A total of 1082 FET cycles with cleavage stage embryos (C-FET) (855 from IVF and 227 from ICSI) and 653 frozen-thawed blastocyst transfer cycles (B-FET) (525 from IVF and 128 from ICSI) were included. There was no significant change in clinical pregnancy, biochemical pregnancy and miscarriage rates in the group with a SDF >30% compared with the group with a SDF ?30% in IVF and ICSI cycles with C-FET or B-FET. Also, there was no significant impact on the FET clinic outcome in IVF and ICSI when different values of SDF (such as 10%, 20%, 25%, 35%, and 40%) were taken as proposed threshold levels. However, the blastulation rates were significantly higher in the SDF ?30% group in ICSI cycle. Taken together, our data show that sperm DNA fragmentation measured by Sperm Chromatin Dispersion (SCD) test is not associated with clinical outcome of FET in IVF and ICSI. Nonetheless, SDF is related to the blastocyst formation in ICSI cycles.
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Exome sequencing analysis identifies compound heterozygous mutation in ABCA4 in a Chinese family with Stargardt disease.
PLoS ONE
PUBLISHED: 01-01-2014
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Stargardt disease is the most common cause of juvenile macular dystrophy. Five subjects from a two-generation Chinese family with Stargardt disease are reported in this study. All family members underwent complete ophthalmologic examinations. Patients of the family initiated the disease during childhood, developing progressively impaired central vision and bilateral atrophic macular lesions in the retinal pigmental epithelium (RPE) that resembled a "beaten-bronze" appearance. Peripheral venous blood was obtained from all patients and their family members for genetic analysis. Exome sequencing was used to analyze the exome of two patients II1, II2. A total of 50709 variations shared by the two patients were subjected to several filtering steps against existing variation databases. Identified variations were verified in all family members by PCR and Sanger sequencing. Compound heterozygous variants p.Y808X and p.G607R of the ATP-binding cassette, sub-family A (ABC1), member 4 (ABCA4) gene, which encodes the ABCA4 protein, a member of the ATP-binding cassette (ABC) transport superfamily, were identified as causative mutations for Stargardt disease of this family. Our findings provide one novel ABCA4 mutation in Chinese patients with Stargardt disease.
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[Microarc oxidation of titanium surfaces on osteoblast morphology and cytoskeleton].
Hua Xi Kou Qiang Yi Xue Za Zhi
PUBLISHED: 12-05-2013
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This study aimed to evaluate the effects of the microarc oxidation surface on cell morphology and cytoskeleton.
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The role of in vivo confocal microscopy in the diagnosis of hidden corneal foreign bodies.
J. Int. Med. Res.
PUBLISHED: 12-04-2013
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To investigate in vivo confocal microscopy (IVCM) to diagnose hidden corneal foreign bodies.
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Ocular Penetration and Pharmacokinetics of Topical Clarithromycin Eye Drops to Rabbits.
J Ocul Pharmacol Ther
PUBLISHED: 11-07-2013
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Abstract Purpose: To evaluate the ocular pharmacokinetics of clarithromycin (CLA) eye drops topically applied to the corneas of rabbits. Methods: One 50-?L drop of CLA (0.25%) was administered to each New Zealand white rabbit in a single dose group, and one 50-?L drop of CLA was administered 6 times at 5-min intervals to each rabbit in a loading dose group. The effect of debridement on corneal penetration was also investigated in a de-epithelium group. The drug concentrations in the cornea and aqueous humor (AH) were assayed using high-performance liquid chromatography with tandem mass spectrometry (HPLC-MS/MS) analysis. Results: Maximum CLA levels were achieved in the corneas and AH at 15 and 60?min, respectively, in the intact epithelium eyes in the single dose group (24.54±10.64??g/g and 0.78±0.22??g/mL, respectively, mean±the standard error of the mean, n=8). In the loading dose group, 30?min after the last application, the CLA level in the corneas reached 92.26±17.62??g/g. In the loading dose group, the drug levels in the corneas and AH were significantly increased compared with the drug levels in the corneas with the intact epithelium and de-epithelium eyes in the single dose group at the corresponding time points (P<0.05). The estimated CLA half-lives in the corneas and AH for the intact eyes were 103.28 and 132.61?min, respectively. Conclusion: Therapeutic CLA levels can be achieved in rabbit corneas after topically applying the drug with eye drops.
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[Case-control study on the risk factors of type 2 diabetes of Dong nationality in Western Hunan].
Zhong Nan Da Xue Xue Bao Yi Xue Ban
PUBLISHED: 10-30-2013
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Objective: To explore the risk factors of type 2 diabetes mellitus (T2DM) of Dong nationality in Western Hunan, and to provide a scientific basis for the prevention and treatment of T2DM in the district. Methods: In the case-control study, the subjects were divided into a T2DM group, an impaired glucose regulation (IGR) group and a normal glucose tolerance (NGT) group through oral glucose tolerance test (OGTT). A questionnaire survey was conducted, and physical measurements and the detection of blood glucose, blood lipids and serum insulin were done. Results: Univariate analysis found significant difference in age, fasting insulin (FINS), HOMA insulin resistance index (HOMA-IRI), HOMA ?-cell function index (HOMA-?C), trigalloyl glycerol (TG), high density lipoprotein cholesterol (HDL-C), systolic blood pressure, and diastolic blood pressure in the glucose metabolism among different groups (P<0.05). Body mass index (BMI), waist/hip ratio (WHR), family history of diabetes, number of physical activities per week, dinner taste, fat and protein-rich foods, fresh vegetables and fruits intake were associated with T2DM. Multifactor non-conditional ordinal logistic regression indicated that age was the risk factor of T2DM and IGR. Compared with the group whose age was?50, the odds ratios of the groups of 5070 were 1.85, 2.83 and 2.64 respectively, P<0.05. The risk of suffering from diabetes of the overweighted or obese people was 2.13 times that of a normal BMI group, P<0.01. The other influencing factors included WHR (OR=2.06), family history of diabetes (OR=11.36), and fat and protein-rich foods (OR=1.90). Conclusion: The main influencing factors of T2DM of Dong nationality in Western Hunan include age, BMI, WHR, family history of diabetes, fat and protein-rich foods. We must strengthen the health eduation of T2DM of Dong nationality in Western Hunan to reduce the risk of T2DM.
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Phosphorylation of nucleoside-metallacarborane and carborane conjugates by nucleoside kinases.
Nucleosides Nucleotides Nucleic Acids
PUBLISHED: 10-16-2013
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A library of purine and pyrimidine nucleosides modified with carborane or metallacarborane boron clusters at different locations, consisting of new molecules as well as already described compounds, was prepared. The compounds were tested as substrates for human deoxynucleoside kinases. Some conjugates, with modification attached to N3 of thymidine via a linker containing the triazole moiety, were efficiently phosphorylated by cytosolic thymidine kinase 1 and mitochondrial thymidine kinase 2. Higher phosphorylation levels were observed with thymidine kinase 1, the phosphorylation of nucleosides modified with metallacarboranes was observed for the first time.
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Heme Oxygenase-1 Exerts a Protective Role in Ovalbumin-induced Neutrophilic Airway Inflammation by Inhibiting Th17 Cell-mediated Immune Response.
J. Biol. Chem.
PUBLISHED: 10-04-2013
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Allergic asthma is conventionally considered as a Th2 immune response characterized by eosinophilic inflammation. Recent investigations revealed that Th17 cells play an important role in the pathogenesis of non-eosinophilic asthma (NEA), resulting in steroid-resistant neutrophilic airway inflammation. Heme oxygenase-1 (HO-1) has anti-inflammation, anti-oxidation, and anti-apoptosis functions. However, its role in NEA is still unclear. Here, we explore the role of HO-1 in a mouse model of NEA. HO-1 inducer hemin or HO-1 inhibitor tin protoporphyrin IX was injected intraperitoneally into ovalbumin-challenged DO11.10 mice. Small interfering RNA (siRNA) was delivered into mice to knock down HO-1 expression. The results show that induction of HO-1 by hemin attenuated airway inflammation and decreased neutrophil infiltration in bronchial alveolar lavage fluid and was accompanied by a lower proportion of Th17 cells in mediastinal lymph nodes and spleen. More importantly, induction of HO-1 down-regulated Th17-related transcription factor retinoic acid-related orphan receptor ?t (ROR?t) expression and decreased IL-17A levels, all of which correlated with a decrease in phosphorylated STAT3 (p-STAT3) level and inhibition of Th17 cell differentiation. Consistently, the above events could be reversed by tin protoporphyrin IX. Also, HO-1 siRNA transfection abolished the effect of hemin induced HO-1 in vivo. Meanwhile, the hemin treatment promoted the level of Foxp3 expression and enhanced the proportion of regulatory T cells (Tregs). Collectively, our findings indicate that HO-1 exhibits anti-inflammatory activity in the mouse model of NEA via inhibition of the p-STAT3-ROR?t pathway, regulating kinetics of ROR?t and Foxp3 expression, thus providing a possible novel therapeutic target in asthmatic patients.
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Pickering emulsion stabilized by lipase-containing periodic mesoporous organosilica particles: A robust biocatalyst system for biodiesel production.
Bioresour. Technol.
PUBLISHED: 09-27-2013
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A novel catalytic system of Pickering emulsion stabilized by lipase-containing periodic mesoporous organosilica was constructed (named LP@PE) and used as biocatalyst for biodiesel production. The reaction parameters were optimized and the optimum conditions were as follows: the water fraction 0.65%, molar ratio of ethanol to oleic acid 2:1, immobilized lipase particles 150mg, phosphate buffer pH 7.0 and temperature 30°C. Under these conditions, the maximum biodiesel yield obtained via esterification of oleic acid with ethanol could reach 95.8%. The biodiesel yield could maintain 88.6% after LP@PE was used 15times. The LP@PE was also used in the synthesis of biodiesel from Jatropha curcas oil. The highest yield could reach 87.1% and the yield was 73.0% after 10 cycles. All these results demonstrated that Pickering emulsion system stabilized by immobilized enzyme may possess much potential in many enzymatic industrial applications.
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Long-term calcium supplementation may have adverse effects on serum cholesterol and carotid intima-media thickness in postmenopausal women: a double-blind, randomized, placebo-controlled trial.
Am. J. Clin. Nutr.
PUBLISHED: 09-18-2013
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Several studies have focused on the effects of calcium intake on serum lipid concentrations in postmenopausal women. However, many premenopausal women are taking calcium supplements in China. To our knowledge, no studies have assessed whether the effects of calcium supplementation on blood lipids are similar between premenopausal and postmenopausal women.
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Two-photon imaging of the cornea visualized in the living mouse using vital dyes.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 09-14-2013
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To acquire morphological and component information on the overall cornea in the living C57BL/6 mouse using fluorescent viability dyes and two-photon (2PH) laser microscopy.
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The role of mitochondrial bioenergetics and reactive oxygen species in coronary collateral growth.
Am. J. Physiol. Heart Circ. Physiol.
PUBLISHED: 08-30-2013
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Coronary collateral growth is a process involving coordination between growth factors expressed in response to ischemia and mechanical forces. Underlying this response is proliferation of vascular smooth muscle and endothelial cells, resulting in an enlargement in the caliber of arterial-arterial anastomoses, i.e., a collateral vessel, sometimes as much as an order of magnitude. An integral element of this cell proliferation is the process known as phenotypic switching in which cells of a particular phenotype, e.g., contractile vascular smooth muscle, must change their phenotype to proliferate. Phenotypic switching requires that protein synthesis occurs and different kinase signaling pathways become activated, necessitating energy to make the switch. Moreover, kinases, using ATP to phosphorylate their targets, have an energy requirement themselves. Mitochondria play a key role in the energy production that enables phenotypic switching, but under conditions where mitochondrial energy production is constrained, e.g., mitochondrial oxidative stress, this switch is impaired. In addition, we discuss the potential importance of uncoupling proteins as modulators of mitochondrial reactive oxygen species production and bioenergetics, as well as the role of AMP kinase as an energy sensor upstream of mammalian target of rapamycin, the master regulator of protein synthesis.
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In situ self-catalyzed reactive extraction of germinated oilseed with short-chained dialkyl carbonates for biodiesel production.
Bioresour. Technol.
PUBLISHED: 07-28-2013
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In order to eliminate the expense associated with solvent extraction and oil cleanup, and reduce the processing steps in biodiesel production, reactive extraction has become a focus of research in recent years. In this study, germinated castor seed was used as substrate and catalyst, dimethyl carbonate (DMC) was used as acyl acceptor and oil extractant to produce biodiesel. The optimum conditions were as follows: the germination time of castor seed was 72h, DMC/germinated seed ratio was 12.5ml/g, reaction temperature was 35°C, and water content was 2.11%. The biodiesel yield could reach as much as 87.41% under the optimized conditions. This germinated oilseed self-catalyzed reactive extraction can be a promising route for biodiesel production.
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What is Visualize?

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

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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

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