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111.
Antibody titers to several heat shock proteins (anti-Hsps) have been reported to be associated with the severity and progression of cardiovascular disease. However, there are little data regarding anti-Hsp27 titers in patients with coronary artery disease (CAD). A total of 400 patients with suspected CAD were recruited. Based on the results of coronary angiography, these patients were classified into CAD+ (n = 300) and CAD (n = 100) groups defined as patients with ≥50% and <50% stenosis of any major coronary artery, respectively. Eighty-three healthy subjects were also recruited as the control group. Serum anti-Hsp27 IgG titers were measured using an in-house enzyme-linked immunosorbent assay. CAD+ patients had significantly higher anti-Hsp27 titers compared with both CAD and control groups. Anti-Hsp27 titers were also higher in the CAD group compared with the control group. With regard to the number of affected vessels in the CAD+ group, patients with three-vessel disease had higher anti-Hsp27 titers compared with both two-vessel disease (2VD) and one-vessel disease (1VD) subgroups. However, there was no significant difference between 1VD and 2VD subgroups. In multiple linear regression analysis, the number of narrowed vessels and smoking were significant independent determinants of serum anti-Hsp27 titers. The present findings indicate that serum anti-Hsp27 titers may be associated with the presence and severity of coronary artery disease.  相似文献   
112.
In this research, ethanol production from carob pod extract (extract) using Zymomonas mobilis with medium optimized by Plackett–Burman (P–B) and response surface methodologies (RSM) was studied. Z. mobilis was recognized as useful for ethanol production from carob pod extract. The effects of initial concentrations of sugar, peptone, and yeast extract as well as agitation rate (rpm), pH, and culture time in nonhydrolyzed carob pod extract were investigated. Significantly affecting variables (P = 0.05) in the model obtained from RSM studies were: weights of bacterial inoculum, initial sugar, peptone, and yeast extract. Acid hydrolysis was useful to complete conversion of sugars to glucose and fructose. Nonhydrolyzed extract showed higher ethanol yield and residual sugar compared with hydrolyzed extract. Ethanol produced (g g−1 initial sugar, as the response) was not significantly different (P = 0.05) when Z. mobilis performance was compared in hydrolyzed and nonhydrolyzed extract. The maximum ethanol of 0.34 ± 0.02 g g−1 initial sugar was obtained at 30°C, initial pH 5.2, and 80 rpm, using concentrations (g per 50 mL culture media) of: inoculum bacterial dry weight, 0.017; initial sugar, 5.78; peptone, 0.43; yeast extract, 0.43; and culture time of 36 h.  相似文献   
113.
Human embryonic stem cells (hESCs) have great potential for use in developmental biology studies, functional genomics applications, drug screening, and regenerative medicine. A detailed understanding of the molecular mechanisms that are responsible for maintaining the undifferentiated and pluripotent nature of hESCs is essential for their effective therapeutic application. It has become evident that many complex cellular processes are carried out by assemblies of protein molecules (protein complexes). Blue native polyacrylamide gel electrophoresis (BN-PAGE) has been used to separate protein complexes from whole cell lysates. Using BN-PAGE, we resolved cytoplasmic and membrane-associated complexes from hESCs and characterised their composition, stoichiometry, and dynamics by denaturing SDS-PAGE. The reliability of the fractionation was examined by western blot analysis of membrane and cytosolic markers. MALDI TOF/TOF mass spectrometry identified 119 cytosolic and 69 membrane proteins from the BN-PAGE proteome maps. Potential protein complexes were validated by computational prediction of possible protein-protein interactions using the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) database. Based on BN-PAGE gels and validation by databases, 82 heteromultimeric and 47 homomultimeric protein complexes have been found in hESCs. Resolving some of the protein complexes provided insight into the function of previously uncharacterised complexes in hESCs.  相似文献   
114.
115.
Fifty-one strains of Fusarium verticillioides and F. proliferatum isolated from corn collected from four different geographic areas in Iran, namely Fars, Khuzestan, Kermanshah and Mazandaran (an endemic oesophageal cancer (OC) area) were evaluated for their ability to produce fumonisins B1 (FB1), B2 (FB2) and B3 (FB3) in corn culture. Fumonisin levels were determined by high-performance liquid chromatography. All tested strains of F. verticillioides and F. proliferatumproduced fumonisins within a wide range of concentrations, 197–9661 g/g, 18–1974 g/g, and 21–1725 g/g for FB1, FB2, and FB3, respectively. The highest mean concentrations of FB1, FB2, and FB3 were 3897, 806 and 827 g/g, respectively. Overall, 61% of the F. verticillioides and F. proliferatum strains produced higher levels of FB3 than FB2. The mean ratios of FB1:FB2, FB1:FB3 and FB1:total fumonisins were 8, 7 and 0.7 for F. verticillioides and 5.7, 10.7 and 0.7 for F. proliferatum, respectively. Significant differences in some of the meteorological data (rainfall, relative humidity and minimum temperature) from the four provinces were observed. Fumonisin levels produced by F. verticillioides strains isolated from Khuzestan province (tropical zone) were significantly (P < 0.01) higher than the other three provinces. This is the first report of the fumonisin-producing ability of F.verticillioides and F. proliferatum strains isolated from corn harvested from different geographic areas in Iran.  相似文献   
116.
A PCR-RFLP method targeted toward 26S rDNA and with 2 restriction enzymes, CfoI and BstF51, was developed to identify 11 Malassezia species. Not only type and standard strains but also 13 clinical isolates were identified successfully in this study. The results of identifications were confirmed by DNA sequencing.  相似文献   
117.
Several series of conformationally constrained N1-arylsulfonyltryptamine derivatives were prepared and tested for 5-HT6 receptor binding affinity and ability to modulate cAMP production in a cyclase assay. The 3-piperidin-3-yl-, 3-(1-methylpyrrolidin-2-ylmethyl)-, and 3-pyrrolidin-3-yl-1H-indole arrays (8-13) appear to be able to adopt a conformation that allows high affinity 5-HT6 receptor binding, while the beta-carboline array 14 binds with a significantly weaker (10- to 100-fold) affinity. N1-Benzenesulfonyl-3-piperidin-3-yl-1H-indole 9a is a high affinity full agonist with EC50 = 24 nM. Several of the N1-arylsulfonyl-3-(1-methylpyrrolidin-2-ylmethyl)-1H-indole derivatives behave as very potent antagonists ((S)-11r, (S)-11t; IC50 = 0.8, 1.0 nM).  相似文献   
118.

Background

The aim of the study was to assess the chronic effects of combined phosphodiesterase 3/4 inhibitor tolafentrine, administered by inhalation, during monocrotaline-induced pulmonary arterial hypertension (PAH) in rats.

Methods

CD rats were given a single subcutaneous injection of monocrotaline to induce PAH. Four weeks after, rats were subjected to inhalation of tolafentrine or sham nebulization in an unrestrained, whole body aerosol exposure system. In these animals (i) the acute pulmonary vasodilatory efficacy of inhaled tolafentrine (ii) the anti-remodeling effect of long-term inhalation of tolafentrine (iii) the effects of tolafentrine on the expression profile of 96 genes encoding cell adhesion and extracellular matrix regulation were examined. In addition, the inhibitory effect of tolafentrine on ex vivo isolated pulmonary artery SMC cell migration was also investigated.

Results

Monocrotaline injection provoked severe PAH (right ventricular systolic pressure increased from 25.9 ± 4.0 to 68.9 ± 3.2 after 4 weeks and 74.9 ± 5.1 mmHg after 6 weeks), cardiac output depression and right heart hypertrophy. The media thickness of the pulmonary arteries and the proportion of muscularization of small precapillary resistance vessels increased dramatically, and the migratory response of ex-vivo isolated pulmonary artery smooth muscle cells (PASMC) was increased. Micro-arrays and subsequent confirmation with real time PCR demonstrated upregulation of several extracellular matrix regulation and adhesion genes, such as matrixmetalloproteases (MMP) 2, 8, 9, 10, 11, 12, 20, Icam, Itgax, Plat and serpinb2. When chronically nebulized from day 28 to 42 (12 daily aerosol maneuvers), after full establishment of severe pulmonary hypertension, tolafentrine reversed about 60% of all hemodynamic abnormalities, right heart hypertrophy and monocrotaline-induced structural lung vascular changes, including the proportion of pulmonary artery muscularization. The upregulation of extracellular matrix regulation and adhesion genes was reduced by nearly 80% by inhalation of the tolafentrine. When assessed in vitro, tolafentrine blocked the enhanced PASMC migratory response.

Conclusion

In conclusion, we demonstrate for the first time that inhalation of combined PDE3/4 inhibitor reverses pulmonary hypertension fully developed in response to monocrotaline in rats. This "reverse-remodeling" effect includes structural changes in the lung vascular wall and key molecular pathways of matrix regulation, concomitant with 60% normalization of hemodynamics.  相似文献   
119.
A simple, selective and sensitive high-performance liquid chromatographic method with spectrophotometric detection was developed for the determination of antihyperglycemic agent metformin in human plasma using a novel sample extraction procedure. Liquid-liquid extraction of metformin and ranitidine (as internal standard) from plasma samples was performed with 1-butanol/n-hexane (50:50, v/v) in alkaline condition followed by back-extraction into diluted acetic acid. Chromatography was carried out using a silica column (250 mmx4.6 mm, 5 microm) under isocratic elution with acetonitrile-40 mM aqueous sodium dihydrogen phosphate (25:75, v/v), pH 6. The limit of quantification (LOQ) was 15.6 ng/ml and the calibration curves were linear up to 2000 ng/ml. The mean absolute recoveries for metformin and internal standard using the present extraction procedure were 98 and 95%, respectively. The intra- and inter-day coefficient of variation and percent error values of the assay method were all less than 8.3%.  相似文献   
120.
Chemical modification of lysine residues in glucose oxidase was carried out using citraconic anhydride. Modification brought about changes in the kinetic properties of the enzyme as evident by substantial lowering of V(max) and K(m). Enhancement of tryptophan fluorescence was observed with a dramatic change in its pH dependence due to modification. Near- and far-UV circular dichroism spectra of the native and modified forms suggested formation of molten globule-like structures, further supported by 8-anilino-1-naphthalenesulfonic acid fluorescence which indicated higher exposure of hydrophobic residues as a result of chemical modification.  相似文献   
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