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Find video protocols related to scientific articles indexed in Pubmed.
A new acidophilic thermostable endo-1,4-ß-mannanase from Penicillium oxalicum GZ-2: cloning, characterization and functional expression in Pichia pastoris.
BMC Biotechnol.
PUBLISHED: 07-12-2014
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BackgroundEndo-1,4-ß-mannanase is an enzyme that can catalyze the random hydrolysis of ß-1, 4-mannosidic linkages in the main chain of mannans, glucomannans and galactomannans and has a number of applications in different biotechnology industries. Penicillium oxalicum is a powerful hemicellulase-producing fungus (Bioresour Technol 123:117-124, 2012); however, few previous studies have focused on the cloning and expression of the endo-1,4-ß-mannanase gene from Penicillium oxalicum.ResultsA gene encoding an acidophilic thermostable endo-1,4-ß-mannanase (E.C. 3.2.1.78) from Penicillium oxalicum GZ-2, which belongs to glycoside hydrolase family 5, was cloned and successfully expressed in Pichia pastoris GS115. A high enzyme activity (84.4 U mL¿1) was detected in the culture supernatant. The recombinant endo-1,4-ß-mannanase (rPoMan5A) was tagged with 6¿×¿His at its C-terminus and purified using a Ni-NTA Sepharose column to apparent homogeneity. The purified rPoMan5A showed a single band on SDS-PAGE with a molecular mass of approximately 61.6 kDa. The specific activity of the purified rPoMan5A was 420.9 U mg¿1 using locust bean gum as substrate. The optimal catalytic temperature (10 min assay) and pH value for rPoMan5A are 80°C and pH 4.0, respectively. The rPoMan5A is highly thermostable with a half-life of approximately 58 h at 60°C at pH 4.0. The K m and V max values for locust bean gum, konjac mannan, and guar gum are 7.6 mg mL¿1 and 1425.5 ¿mol min¿1 mg¿1, 2.1 mg mL¿1 and 154.8 ¿mol min¿1 mg¿1, and 2.3 mg mL¿1 and 18.9 ¿mol min¿1 mg¿1, respectively. The enzymatic activity of rPoMan5A was not significantly affected by an array of metal ions, but was inhibited by Fe3+ and Hg2+. Analytical results of hydrolytic products showed that rPoMan5A could hydrolyze various types of mannan polymers and released various mannose and manno-oligosaccharides, with the main products being mannobiose, mannotriose, and mannopentaose.ConclusionOur study demonstrated that the high-efficient expression and secretion of acid stable and thermostable recombinant endo-1, 4-ß-mannanase in Pichia pastoris is suitable for various biotechnology applications.
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A new acidophilic endo-?-1,4-xylanase from Penicillium oxalicum: cloning, purification, and insights into the influence of metal ions on xylanase activity.
J. Ind. Microbiol. Biotechnol.
PUBLISHED: 02-20-2014
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A new acidophilic xylanase (XYN11A) from Penicillium oxalicum GZ-2 has been purified, identified and characterized. Synchronized fluorescence spectroscopy was used for the first time to evaluate the influence of metal ions on xylanase activity. The purified enzyme was identified by MALDI TOF/TOF mass spectrometry, and its gene (xyn11A) was identified as an open reading frame of 706 bp with a 68 bp intron. This gene encodes a mature protein of 196 residues with a predicted molecular weight of 21.3 kDa that has the 100 % identity with the putative xylanase from the P. oxalicum 114-2. The enzyme shows a structure comprising a catalytic module family 10 (GH10) and no carbohydrate-binding module family. The specific activities were 150.2, 60.2, and 72.6 U/mg for beechwood xylan, birchwood xylan, and oat spelt xylan, respectively. XYN11A exhibited optimal activity at pH 4.0 and remarkable pH stability under extremely acidic condition (pH 3). The specific activity, K m and V max values were 150.2 U/mg, 30.7 mg/mL, and 403.9 ?mol/min/mg for beechwood xylan, respectively. XYN11A is a endo-?-1,4-xylanase since it release xylobiose and xylotriose as the main products by hydrolyzing xylans. The activity of XYN11A was enhanced 155 % by 1 mM Fe(2+) ions, but was inhibited strongly by Fe(3+). The reason of enhancing the xylanase activity of XYN11A with 1 mM Fe(2+) treatment may be responsible for the change of microenvironment of tryptophan residues studied by synchronous fluorescence spectrophotometry. Inhibition of the xylanase activity by Fe(3+) was first time demonstrated to associate tryptophan fluorescence quenching.
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Clinical pharmacokinetics of Icotinib, an anti-cancer drug: evaluation of dose proportionality, food effect, and tolerability in healthy subjects.
Cancer Chemother. Pharmacol.
PUBLISHED: 01-21-2014
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Icotinib, an oral epidermal growth factor receptor tyrosine kinase inhibitor, has proved effectiveness in xenografted nude mice. Purpose of the present studies was to investigate tolerability and pharmacokinetics of Icotinib in healthy subjects for the first time, including dose proportionality, food effect, and tolerability.
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Operation performance and microbial community dynamics of phosphorus removal sludge with different electron acceptors.
J. Ind. Microbiol. Biotechnol.
PUBLISHED: 01-09-2014
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Operation performances of phosphorus removal sludge with different electron acceptors in three parallel SBRs were firstly compared in the present study, and the effect of post-aeration on denitrifying phosphorus removal was also studied. Moreover, community dynamics of different phosphorus removal sludge was systematically investigated with high-throughput sequencing for the first time. TP removal rates for nitrate-, nitrite-, and oxygen-based phosphorus removal sludge were 84.8, 78.5, and 87.4 %, with an average effluent TP concentration of 0.758, 0.931, and 0.632 mg/l. The average specific phosphorus release and uptake rates were 20.3, 10.8, and 21.5, and 9.43, 8.68, and 10.8 mgP/(gVSS h), respectively. Moreover, electron utilization efficiency of denitrifying phosphorus removal sludge with nitrate as electron acceptor was higher than nitrite, with P/e(-) were 2.21 and 1.51 mol-P/mol-e(-), respectively. With the assistance of post-aeration for nitrate-based denitrifying phosphorus removal sludge, settling ability could be improved, with SVI decreased from 120 to 80 and 72 ml/g when post-aeration time was 0, 10, and 30 min, respectively. Moreover, further phosphorus removal could be achieved during post-aeration with increased aeration time. However, the anoxic phosphorus uptake was deteriorated, which was likely a result of shifted microbial community structure. Post-aeration of approximately 10 min was proposed for denitrifying phosphorus removal. Nitrate- and nitrite-based denitrifying phosphorus removal sludge exhibited similar community structure. More phosphorus accumulating organisms were enriched under anaerobic-aerobic conditions, while anaerobic-anoxic conditions were favorable for suppressing glycogen-accumulating organisms. Significant differences in pathogenic bacterial community profiles revealed in the current study indicated the potential public health hazards of non-aeration activated sludge system.
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Modeling pharmacokinetics/pharmacodynamics of abatacept and disease progression in collagen-induced arthritic rats: a population approach.
J Pharmacokinet Pharmacodyn
PUBLISHED: 07-12-2013
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The PK/PD of abatacept, a selective T cell co-stimulation modulator, was examined in rats with collagen-induced arthritis (CIA) using a nonlinear mixed effect modeling approach. Male Lewis rats underwent collagen induction to produce rheumatoid arthritis. Two single-dose groups received either 10 mg/kg intravenous (IV) or 20 mg/kg subcutaneous (SC) abatacept, and one multiple-dose group received one 20 mg/kg SC abatacept dose and four additional 10 mg/kg SC doses. Effects on disease progression (DIS) were measured by paw swelling. Plasma concentrations of abatacept were assayed by enzyme-linked immunosorbent assay. The PK/PD data were sequentially fitted using NONMEM VI. Goodness-of-fit was assessed by objective functions and visual inspection of diagnostic plots. The PK of abatacept followed a two-compartment model with linear elimination. For SC doses, short-term zero-order absorption was assumed with F = 59.2 %. The disease progression component was an indirect response model with a time-dependent change in paw edema production rate constant (k in ) that was inhibited by abatacept. Variation in the PK data could be explained by inter-individual variability in clearance and central compartment volume (V 1 ), while the large variability of the PD data may be the result of paw edema production (k in (0) ) and loss rate constant (k out ). Abatacept has modest effects on paw swelling in CIA rats. The PK/PD profiles were well described by the proposed model and allowed evaluation of inter-individual variability on drug- and DIS-related parameters.
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Secretome diversity and quantitative analysis of cellulolytic Aspergillus fumigatus Z5 in the presence of different carbon sources.
Biotechnol Biofuels
PUBLISHED: 06-10-2013
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Aspergillus fumigatus Z5 has a strong ability to decompose lignocellulose biomass, and its extracellular protein secretion has been reported in earlier studies employing traditional techniques. However, a comprehensive analysis of its secretion in the presence of different carbon sources is still lacking. The goal of this work was to identify, quantify and compare the secretome of A. fumigatus Z5 in the presence of different carbon sources to understand in more details the mechanisms of lignocellulose decomposition by Aspergillus fumigatus Z5.
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Exogenous ARC down-regulates caspase-3 expression and inhibits apoptosis of broiler chicken cardiomyocytes exposed to hydrogen peroxide.
Avian Pathol.
PUBLISHED: 02-09-2013
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Apoptosis repressor with caspase recruitment domain (ARC) is highly involved in apoptosis induced by oxidative stress or ischaemia/reperfusion injury. Furthermore, even though the exact mechanism is still unknown, some studies suggest that exogenous ARC also possesses anti-apoptotic ability. The study investigated whether mouse-derived ARC acquires anti-apoptotic ability and the pathway of regulation in chick embryo cardiomyocytes. To evaluate whether mouse-derived ARC can inhibit chick embryo cardiomyocyte apoptosis induced by hydrogen peroxide, recombinant pcDNA3.1/ARC plasmid was acquired and transfected into chick embryo cardiomyocytes. ARC-related gene (caspase-2, caspase-8, caspase-3, and caspase-9, cytochrome C, bcl-2, and XIAP) mRNA and protein expression levels were detected by real-time polymerase chain reaction and western blotting, respectively. Here we demonstrate that hydrogen peroxide induced apoptosis in chick embryo cardiomyocytes in a time-dependent manner and that this effect could be suppressed by mouse-derived ARC expression. Moreover, unlike endogenous ARC, exogenous ARC was exclusively expressed in the cytoplasm and down-regulated caspase-2, caspase-8, and caspase-3, bcl-2, and XIAP gene expression levels. However, only caspase-3 protein levels were decreased. In addition, threonine 149 phosphorylation by CK2 was required for exogenous ARC to exert an anti-apoptotic effect in chicken embryo cardiomyocytes and suggested exogenous ARC may in part share the same pathway of regulation with endogenous ARC. These results indicate that mouse-derived ARC plays an important role in protection of chick embryo cardiomyocytes against oxidative stress apoptosis by inhibiting caspase-3 mRNA and protein expression levels.
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Population pharmacokinetic-pharmacodynamic-disease progression model for effects of anakinra in Lewis rats with collagen-induced arthritis.
J Pharmacokinet Pharmacodyn
PUBLISHED: 07-13-2011
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A population pharmacokinetic-pharmacodynamic-disease progression (PK/PD/DIS) model was developed to characterize the effects of anakinra in collagen-induced arthritic (CIA) rats and explore the role of interleukin-1? (IL-1?) in rheumatoid arthritis. The CIA rats received either vehicle, or anakinra at 100 mg/kg for about 33 h, 100 mg/kg for about 188 h, or 10 mg/kg for about 188 h by subcutaneous infusion. Plasma concentrations of anakinra were assayed by enzyme-linked immunosorbent assay. Swelling of rat hind paws was measured. Population PK/PD/DIS parameters were computed for the various groups using non-linear mixed-effects modeling software (NONMEM® Version VI). The final model was assessed using visual predictive checks and nonparameter stratified bootstrapping. A two-compartment PK model with two sequential absorption processes and linear elimination was used to capture PK profiles of anakinra. A transduction-based feedback model incorporating logistic growth rate captured disease progression and indirect response model I captured drug effects. The PK and paw swelling versus time profiles in CIA rats were fitted well. Anakinra has modest effects (I ( max ) = 0.28) on paw edema in CIA rats. The profiles are well-described by our PK/PD/DIS model which provides a basis for future mechanism-based assessment of anakinra dynamics in rheumatoid arthritis.
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Metabolite characterization of a novel anti-cancer agent, icotinib, in humans through liquid chromatography/quadrupole time-of-flight tandem mass spectrometry.
Rapid Commun. Mass Spectrom.
PUBLISHED: 07-07-2011
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Icotinib is a novel anti-cancer drug that has shown promising clinical efficacy and safety in patients with non-small-cell lung cancer (NSCLC). At this time, the metabolic fate of icotinib in humans is unknown. In the present study, a liquid chromatography/quadrupole time-of-flight tandem mass spectrometry (LC/Q-TOF MS) method was established to characterize metabolites of icotinib in human plasma, urine and feces. In addition, nuclear magnetic resonance (NMR) detection was utilized to determine the connection between side-chain and quinazoline groups for some complex metabolites. In total, 29 human metabolites (21 isomer metabolites) were characterized, of which 23 metabolites are novel compared to the metabolites in rats. This metabolic study revealed that icotinib was extensively metabolized at the 12-crown-4 ether moiety (ring-opening and further oxidation), carbon 15 (hydroxylation) and an acetylene moiety (oxidation) to yield 19 oxidized metabolites and to further form 10 conjugates with sulfate acid or glucuronic acid. To our knowledge, this is the first report of the human metabolic profile of icotinib. Study results indicated that significant attention should be paid to the metabolic profiles of NSCLC patients during the development of icotinib.
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Changes in biochemical and microbiological parameters during the period of rapid composting of dairy manure with rice chaff.
Bioresour. Technol.
PUBLISHED: 05-06-2011
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Various parameters were measured during the period of composting of dairy manure and rice chaff in different ratios (dairy manure/rice chaff=V/V, pile 1: 75/25; pile 2: 80/20; pile 3: 85/15) to evaluate their suitability as indicators for the composting process. The temperature in pile 1 increased rapidly and remained above 60 °C for 30 days, while the temperature in pile 3 increased slowly relative to the other two piles. Furthermore, the degradation of organic substrates, as indicated by the reduction of C/N ratio, was rapid in pile 1 (below 20% 28 days after beginning of the composting). The major fluctuations of various water-soluble fractions in all piles were observed during the first 3 weeks, and the results in general showed that the highest microbial populations and enzymatic activities also appeared in this phase. Various parameters indicated that the rapid composting method was a feasible one for treating agricultural wastes.
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Expression, purification and characterization of two thermostable endoglucanases cloned from a lignocellulosic decomposing fungi Aspergillus fumigatus Z5 isolated from compost.
Protein Expr. Purif.
PUBLISHED: 03-09-2011
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Two genes encoding endoglucanase, designated as egl2 and egl3, were cloned from a lignocellulosic decomposing fungus Aspergillus fumigatus Z5 and were successfully expressed in Pichia pastoris X33. The deduced amino acid sequences encoded by egl2 and egl3 showed strong similarity with the sequence of glycoside hydrolase family 5. SDS-PAGE and western blot assays indicated that the recombinant enzymes were secreted into the culture medium and the zymogram analysis confirmed that both recombinant enzymes had endoglucanase activity. Several biochemical properties of the two recombinant enzymes were studied: Egl2 and Egl3 showed optimal activity at pH 5.0 and 4.0, respectively, and at 50 and 60°C, respectively. Egl2 and Egl3 showed good pH stability in the range of 4-7, and both enzymes demonstrated good thermostability ranging from 30 to 60°C. The K(m) and V(max) values using carboxymethyl cellulose (CMC, soluble cellulose, polymerized by ?-1, 4-linked glucose residues) as the substrate at optimal conditions were determined. The activities of the enzymes on a variety of cello-oligosaccharide substrates were investigated, and Egl2 can hydrolyze cellotetraose and cellopentaose but not cellobiose and cellotriose, whereas Egl3 can hydrolyze all cello-oligosaccharides, except cellobiose.
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Pharmacokinetic-pharmacodynamic disease progression model for effect of etanercept in Lewis rats with collagen-induced arthritis.
Pharm. Res.
PUBLISHED: 02-08-2011
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To develop a pharmacokinetic-pharmacodynamic disease progression (PK/PD/DIS) model to characterize the effect of etanercept in collagen-induced arthritis (CIA) rats on rheumatoid arthritis (RA) progression.
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Phase I study of icotinib hydrochloride (BPI-2009H), an oral EGFR tyrosine kinase inhibitor, in patients with advanced NSCLC and other solid tumors.
Lung Cancer
PUBLISHED: 08-02-2010
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The goal of this study was to assess the safety and tolerability of icotinib hydrochloride (BPI-2009H), a new selective epidermal growth factor receptor tyrosine kinase inhibitor (EGFR TKI), and to explore its pharmacokinetics (PK) and clinical activity in patients with advanced solid tumors, mainly those with non-small-cell lung cancer (NSCLC) after the failure of the prior platinum-based chemotherapy.
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Different analysis techniques for fluorescence excitation-emission matrix spectroscopy to assess compost maturity.
Chemosphere
PUBLISHED: 07-23-2010
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Assessment of compost maturity is essential for achieving high quality compost. In this study, fluorescence excitation-emission matrix spectroscopy combined with different analysis techniques was applied to improve the sensitivity of compost maturity assessment. Results showed that composts in two parallel piles could be believed mature after 37d when combined with the evolution of temperature, chemical and biological indices in the two piles. Pearson correlation between the common maturity indices and fluorescence analysis parameters demonstrated that fluorescence regional integration (FRI) had a higher correlation coefficient than that of fluorescence intensities and the ratios of peaks, suggesting that FRI technique is more suitable to characterize the maturity of compost than the other two analysis techniques, i.e., peak intensity and peak ratio. Furthermore, the fluorescence spectroscopy combined with FRI analysis could be used as a valuable industrial and research tool for assessing compost maturity.
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Simultaneous quantitative determination of olmesartan and hydrochlorothiazide in human plasma and urine by liquid chromatography coupled to tandem mass spectrometry.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 01-07-2010
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A specific, sensitive and rapid method based on high performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) was developed for the simultaneous determination of olmesartan (OLM) and hydrochlorothiazide (HCTZ) in human plasma and urine. Solid-phase extraction (SPE) was used to isolate the analytes from biological matrices followed by injection of the extracts onto a C(18) column with isocratic elution. Detection was carried out on a triple quadrupole tandem mass spectrometer in multiple reaction monitoring (MRM) mode using negative electrospray ionization (ESI). The method was validated over the concentration range of 1.00-1000 ng/mL and 5.00-5000 ng/mL for OLM in human plasma and urine as well as 0.500-200 ng/mL and 25.0-25,000 ng/mL for HCTZ in human plasma and urine, respectively. Inter- and intra-run precision of OLM and HCTZ were less than 15% and the accuracy was within 85-115% for both plasma and urine. The average extraction recoveries were 96.6% and 92.7% for OLM, and 87.2% and 72.1% for HCTZ in human plasma and urine, respectively. The linearity, recovery, matrix effect and stability were validated for OLM/HCTZ in human plasma and urine.
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Quantitative determination of icotinib in human plasma and urine using liquid chromatography coupled to tandem mass spectrometry.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 06-22-2009
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We developed a rapid, specific and sensitive method based on high performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) to determine icotinib concentrations in human plasma and urine. Liquid-liquid extraction (LLE) and direct dilution were firstly used to isolate icotinib from plasma and urine followed by injection of the extracts onto a C(18) column with gradient elution. Ionization of icotinib and midazolam (internal standard, IS) was performed using an electrospray ionization source in positive mode and detection was carried out in multi-reaction monitoring (MRM) mode. The lower limits of quantitation (LLoQ) of icotinib in human plasma and urine by this method were 0.1 and 1.00ng/mL, respectively. The accuracy, precision, specificity, recovery, matrix effect, linearity and several of stabilities have been validated for icotinib in human plasma and urine. In conclusion, the validation results showed that this method is robust, specific and sensitive and it can successfully fulfill the requirement of clinical pharmacokinetic study of icotinib hydrochloride in Chinese healthy subjects.
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Pharmacokinetic and safety profile of olmesartan medoxomil in healthy Chinese subjects after single and multiple administrations.
Pharmazie
PUBLISHED: 06-18-2009
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The primary aim of this study was to investigate the pharmacokinetics and safety of daily oral doses of olmesartan medoxomil administered to healthy Chinese subjects for 7 days. All 14 subjects (8 males/6 females) received a single dose of 20 mg olmesartan medoxomil and followed by multiple oral doses of 20 mg olmesartan medoxomil once daily for 7 days. Blood and urine samples were obtained for a 48-h pharmacokinetic evaluation on two PK days (Day 1 and Day 9). The systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate were determined at the scheduled time for safety evaluation. The concentration of RNH-6270 (olmesartan, the unique available metabolite of olmesartan medoxomil in vivo) in plasma and urine were determined with HPLC-MS/MS method after solid-phase extraction. Pharmacokinetic parameters tmax, Cmax, t 1/2, AUC (0, 24 h), AUC(0-infinity), and CLr of RNH-6270 were derived from the concentration-time profiles for single- and multiple-dose administration. The pharmacokinetic parameters were summarized by gender and treatment factors which were tested by ANOVA. The results showed that there was no significant difference between male and female. Safety results showed that the decrease of blood pressure was consistent with increase of concentration of RNH-6270 and heart rate was consistent. Based above analysis, it was concluded that olmesartan medoxomil 20 mg was safe and there were no any accumulation in healthy Chinese subjects after multiple-dose.
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The subpleural pulmonary microvasculature in newborn yak (Bos grunniens).
Vet. Res. Commun.
PUBLISHED: 05-21-2009
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Yak is a unique domestic animal of Qinghai-Tibetan Plateau. Its unique adaptability to the high altitude environment has been hypothesized due to special pulmonary microvasculature. However, the anatomical evidence is still less. The present study characterized the subpleural pulmonary microvascular architecture of newborn yak by vascular corrosion cast and the scanning electron microscopy. The results showed the dense vascular network occurred in subpleural area in newborn yak. Subpleural vascular network was found in most of observed areas, while the sparse vascular network crept onto the subpleural network in some fields of view. The subpleural microvessels and their branches made up of the subpleural microvascular network. According to the branching sequence of vessels, the subpleural arterioles could be divided into four grades: the arteriole, terminal arteriole, precapillary arteriole and capillary. The subpleural capillary network in the local area could be classified into three different forms, including sheetlike vascular network, wrinkled vascular network and weblike vascular network. It was the specific characteristics on the cast surface of the microvessels that was the adaptable peculiarities. Anastomoses were found between the pleural microvessels and the interlobular capillaries, or between the pleural microvessels and the subpleural capillaries, or between the interlobular capillaries and the subpleural capillaries. Therefore, there was significant difference on the subpleural pulmonary microvasculature between newborn yak and other adult mammals.
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Pharmacokinetics and pharmacodynamics of vildagliptin in healthy Chinese volunteers.
J Clin Pharmacol
PUBLISHED: 02-26-2009
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Vildagliptin is an orally effective, potent, and selective inhibitor of dipeptidyl peptidase IV (DPP-4) that improves glycemic control in patients with type 2 diabetes. This was a randomized, double-blind, placebo-controlled, time-lagged, parallel-group study in a total of 60 healthy Chinese participants. Single- and multiple-dose pharmacokinetics and pharmacodynamics, and safety and tolerability of vildagliptin were assessed following administration of 25, 50, 100, or 200 mg qd, or 50 mg bid. Vildagliptin was rapidly absorbed (tmax 1.5-2.0 hours) across the dose range of 25 to 200 mg and was quickly eliminated with a terminal elimination half-life (t1/2) of approximately 2 hours. Consistent with the short t1/2, no accumulation of vildagliptin was observed following the administration of multiple doses (accumulation factors were 1.00-1.05 across the 25- to 200-mg dose range). Vildagliptin AUC and Cmax values increased in an approximately dose-proportional fashion (dose proportionality constant beta 1.00-1.16). Administration of vildagliptin 25 to 200 mg led to rapid and near-complete (>95%) inhibition of DPP-4 activity for at least 4 hours after dosing, which was associated with increases in plasma active glucagon-like peptide-1 of up to 2- to 3-fold compared with placebo. The duration of DPP-4 inhibition increased with dose. Glucose and insulin levels were not affected by vildagliptin in healthy participants, consistent with the fact that the glucose-lowering effects of vildagliptin occur in a glucose-dependent fashion. Vildagliptin was well tolerated at the highest tested dose of 200 mg qd. Vildagliptin 25 to 200 mg qd exhibits approximately dose-proportional pharmacokinetics with no evidence of accumulation after multiple dosing in healthy Chinese participants. Vildagliptin demonstrates potent inhibition of DPP-4 activity with excellent tolerability at doses of up to and including 200 mg qd.
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An optimized DNA extraction and purification method from dairy manure compost for genetic diversity analysis.
World J. Microbiol. Biotechnol.
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An unbiased DNA extraction protocol is necessary for analysis of genetic diversity, particularly, of genes in complex environmental samples by nucleic acid techniques. In the present study, three manual extraction methods and two commonly used commercial kits, which were accompanied by two DNA purification strategies, were compared based on cell lysis efficiency, DNA and humic acid yields, PCR amplification and denaturing gradient gel electrophoresis (DGGE) analysis. The results show that in spite of higher cell lysis efficiencies of the two commercial kits, the purified DNA yields were only one-third of that obtained by the two manual methods of FTSP (Freeze-thaw-SDS-Protein K) and FTSPP (Freeze-thaw-SDS-Protein K-Polyvinylpolypyrrolidone). The purified DNA from all five methods was pure enough for successful PCR and real-time PCR amplifications in the presence of 1 ?g ?L(-1) BSA. However, the FTSPP extraction method with DNA purification by a Wizard(®) kit yielded the largest number of 16S rRNA gene copies and ribotypes or bands in DGGE profiles, which indicated a superiority over the other four methods. The development of this optimized DNA extraction and purification method may provide a valuable tool for further molecular analysis of compost.
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Pharmacokinetic/pharmacodynamic modeling in inflammation.
Crit Rev Biomed Eng
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Inflammation is an array of immune responses to infection and injury. It results from a complex immune cascade and is the basis of many chronic diseases such as arthritis, diabetes, and cancer. Numerous mathematical models have been developed to describe the disease progression and effects of anti-inflammatory drugs. This review illustrates the state of the art in modeling the effects of diverse drugs for treating inflammation, describes relevant biomarkers amenable to modeling, and summarizes major advantages and limitations of the published pharmacokinetic/ pharmacodynamic (PK/PD) models. Simple direct inhibitory models are often used to describe in vitro effects of anti-inflammatory drugs. Indirect response models are more mechanism based and have been widely applied to the turnover of symptoms and biomarkers. These, along with target-mediated and transduction models, have been successfully applied to capture the PK/PD of many anti-inflammatory drugs and describe disease progression of inflammation. Biologics have offered opportunities to address specific mechanisms of action, and evolve small systems models to quantitatively capture the underlying physiological processes. More advanced mechanistic models should allow evaluation of the roles of some key mediators in disease progression, assess drug interactions, and better translate drug properties from in vitro and animal data to patients.
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Characterization of a thermostable ?-glucosidase from Aspergillus fumigatus Z5, and its functional expression in Pichia pastoris X33.
Microb. Cell Fact.
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Recently, the increased demand of energy has strongly stimulated the research on the conversion of lignocellulosic biomass into reducing sugars for the subsequent production, and ?-glucosidases have been the focus because of their important roles in a variety fundamental biological processes and the synthesis of useful ?-glucosides. Although the ?-glucosidases of different sources have been investigated, the amount of ?-glucosidases are insufficient for effective conversion of cellulose. The goal of this work was to search for new resources of ?-glucosidases, which was thermostable and with high catalytic efficiency.
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