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Based on the new thermodynamic theory, a new model was suggested to calculate the specific heat capacities of monoatomic gas, He, and diatomic gas, O2. The theory suggests a portion of gas molecules with the highest kinetic energy affords the heat exchange to sustain the state equilibrium by inelastically colliding and liquefying on the container walls, whereas the rest elastically colliding with walls creates pressure. Accordingly, a general equation of specific heat capacity is established on the density of liquid and gas. Given ∂lnVL∂lnTP ${{\left[{{\partial ln{V}_{L}}\over{\partial lnT}}\right]}_{P}}$ at isobar and ∂P∂TV ${{\left[{{\partial P}\over{\partial T}}\right]}_{V}}$ at isochore, Cp and Cv at any temperature can be calculated with the densities of gas and liquid (or solid). Employing the available data of He and O2 issued by NIST, Cps, and Cvs are calculated. The results fit the reference data well. [ABSTRACT FROM AUTHOR]

Background. To accurately evaluate sports social discipline's academic influence in China, a model of academic influence evaluation of sports social discipline in China based on bibliometrics is proposed. Objective. A statistical model of the academic influence of sports social discipline is constructed, the word frequency statistics method is used to measure the literature, and the semantic characteristic quantity of the sports social discipline academic influence is extracted, using the literature method and logical analysis method to analyze sports' social value in the Internet era from healthy sports. The combination of sports and medical treatment can comprehensively promote physical and mental health. Methods. The dual semantic feature decomposition method is used to analyze sports social discipline's academic influence. The statistical analysis model of sports social discipline academic influence is established. The principles of fuzzy pattern recognition include the principle of maximum membership degree and proximity degree. Results. The comprehensive relative closeness of the distribution of literature statistics on sports and social disciplines' academic influence is constructed. The linear programming analysis of literature statistics is carried out using the standardized grid computing method. Conclusions. The combination of association rule feature extraction and semantic feature extraction is used to realize the quantitative calculation of literature statistics and academic influence. The simulation results show that the statistical analysis of the academic influence of sports and social discipline by this method is accurate, and the level of confidence is high. [ABSTRACT FROM AUTHOR]

The enzymatic regioselective acylation of resveratrol was achieved in organic solvents catalyzed by the lipase from Candida sp. 99-125 (CSL) under microwave irradiation. Influences of various reaction conditions have been studied. After selecting the optimum conditions [MTBE (20 ml, aw = 0.38), resveratrol (0.1 mmol), vinyl acetate (1.0 mmol) and CSL (100.0 mg) under microwave irradiation (35°C, 400 W)], CSL exhibited a satisfied enzyme activity (281 ± 11 μmol/g/h) and yield of 75% for 4′-O-acetyl- resveratrol could be obtained in about 4 h when performing the reaction on a 25-fold-larger scale. Schematic illustration of the enzymatic regioselective acylation of resveratrol catalyzed by the lipase from Candida sp. 99-125 (CSL) under microwave irradiation. [ABSTRACT FROM AUTHOR]

A nano-biocatalyst has been successfully prepared via coordination between zinc ion and the nitrogen atoms of the amide groups in the Candida sp. 99-125 lipase. The as-prepared nanoparticle has an excellent hierarchical structure with a large number of separate petals. In regioselective acylation of arbutin, the nano-biocatalyst showed enhanced enzyme activities to about 4.3-folds than the free enzyme. Meanwhile, the prepared nano-biocatalyst exhibited good operational reusability and only about 6% of enzyme activity has lost during 10 continuous reaction-recycles. [ABSTRACT FROM AUTHOR]

Abstract: Previous studies in our lab have identified pre-B-cell colony enhancing factor (PBEF) as a novel biomarker in acute lung injury. This study continues to elucidate the underlying molecular mechanism of PBEF in the pathogenesis of acute lung injury in pulmonary cell culture models. Our results revealed that IL-1β induced PBEF expression in pulmonary vascular endothelial cells at the transcriptional level and a −1535 T-variant in the human PBEF gene promoter significantly attenuated its binding to an IL-1β-induced unknown transcription factor. This may underlie the reduced expression of PBEF and thus the lower susceptibility to acute lung injury in −1535T carriers. Furthermore, overexpression of PBEF significantly augmented IL-8 secretion and mRNA expression by more than 6-fold and 2-fold in A549 cells and HPAEC, respectively. It also significantly augmented IL-1β-mediated cell permeability by 44% in A549 cells and 65% in endothelial cells. The knockdown of PBEF expression significantly inhibited IL-1β-stimulated IL-8 secretion and mRNA level by 60% and 70%, respectively, and the knockdown of PBEF expression also significantly attenuated IL-1β-induced cell permeability by 29% in epithelial cells and 24% in endothelial cells. PBEF expression also affected the expression of two other inflammatory cytokines (IL-16 and CCR3 genes). These results suggest that PBEF is critically involved in pulmonary vascular and epithelial inflammation and permeability, which are hallmark features in the pathogenesis of acute lung injury. This study lends further support to our finding that PBEF is a potential new target in acute lung injury. [Copyright &y& Elsevier]

To investigate the effects of rAdinbitor on the adhesion and proliferation of human hepatoma cell strain SMMC-7721. Cell adhesion assay was used to observe the effect of rAdinbitor on the adhesion of SMMC-7721 cells to fibronectin (FN). Crystal violet staining was performed to detect the influence of rAdinbitor on the adhesion of SMMC-7721 cells. MTT assay was employed to detect the inhibitory effects of different concentration of rAdinbitor on the proliferation of SMMC-7721 cells. The morphologic changes of the control SMMC-7721 cells and the apoptotic cells induced by 200 μg/mL rAdinbitor for 36 h were observed under light microscope after HE staining. Flow cytometry analysis was applied to determine the apoptosis rate of SMMC-7721 cells. (1) FN promoted the adhesion of human hepatoma cell strain SMMC-7721 in a dose-dependent manner. (2) rAdinbitor could dose-dependently inhibit the adhesion of SMMC-7721 cells to FN. The higher the concentration was, the stronger the inhibition was. There was significant difference among the groups ( P < 0.05). (3) rAdinbitor had a strong inhibition on the proliferation of SMMC-7721 cells and showed a dose-dependent manner ( P < 0.05). After a 48 h exposure, the IC50 value of rAdinbitor was 177.83 μg/mL. (4) After exposure of SMMC-7721 cells to 200 μg/mL rAdinbitor for 36 h, the early morphologic changes appeared and the apoptosis rate was 20.68%, significantly higher than that of the control group (2.38%, P < 0.05). rAdinbitor can dose-dependently inhibit the SMMC-7721 cells adhesion to FN, and can inhibit the proliferation in dose-dependent manner and promote their apoptosis. [ABSTRACT FROM AUTHOR]

Transfection activities of two series of synthetic glycerol backbone-based cationic lipids were studied as gene delivery carriers. The variable length of hydrocarbon chains, diverse quaternary ammonium heads, different linkage, as well as alternative anion combined with them allowed to find how these factors affect cationic lipids on their gene delivery performance. The structure–function relationship of the synthetic glycerol backbone-based cationic lipids was discussed, and the transfection efficiency of some of the cationic liposomes was superior or parallel to that of two commercial transfection agents. [ABSTRACT FROM AUTHOR]

Human placental ribonuclease inhibitor (hRI) is an acidic protein of Mr∼50kDa with unusually high contents of leucine and cysteine residues. It is a cytosolic protein that protects cells from the adventitious invasion of pancreatic-type ribonuclease. hRI has 32 cysteine residues, and the oxidative formation of disulfide bonds from those cysteine residues is a rapid cooperative process that inactivates hRI. The most proximal cysteine residues in native hRI are two pairs that are adjacent in sequence. In the present aork, two molecules of alanine substituting for Cys328 and Cys329 were performed by site-directed mutagenesis. The site-mutated RI cDNA was constructed into plasmid pPIC9K and then transformed Pichia pastoris GS115 by electroporation. After colony screening, the bacterium was cultured and the product was purified with affinity chromatography. The affinity of the recombinant human RI with double site mutation was examined for RNase A and its anti-oxidative effect. Results indicated that there were not many changes in the affinity for RNase A detected when compared with the wild type of RI. But the capacity of anti-oxidative effect increased by 7∼9 times. The enhancement in anti-oxidative effect might be attributed to preventing the formation of disulfide bond between Cys328 and Cys329 and the three dimensional structure of RI was thereby maintained. [ABSTRACT FROM AUTHOR]

Abstract Human ribonuclease inhibitor (hRI) can inhibit angiogenesis by reversibly binding angiogenin, a member of the RNaseA superfamily, and by suppressing the expression of basic fibroblast growth factor (bFGF). Angiogenesis is necessary for the growth and metastasis of tumors. To study the links between hRI, angiogenesis, and melanoma growth, the hRI gene was intravenously administered to mice in a recombinant retroviral vector, and expression of the hRI gene was induced to block melanoma angiogenesis. Expression, distribution, and contribution of the target gene in mice were assayed. The results showed that the tumors of mice in the hRI treatment group grew slower with less vascularity than those of mice in control groups. The introduced hRI gene inhibited tumor growth without causing significant side effects in the animals. More hRI expression in vimentin-positive cells of the tumor than in melanoma cells suggested that mesenchymal cells in the fibrous envelope of the tumor play important roles in this gene therapy. [ABSTRACT FROM AUTHOR]