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131.
Electropolarity treatment (0.8V/DC/Cm) was given to the gastrocnemius muscle of B. melanostictus every day for 5 min for 5 days. The glycogen content and aldolase activity levels increased and phosphorylase 'a' activity levels decreased on cathode treatment in muscle, liver and brain while an opposed trend was observed on anode treatment. The heart showed contrasting pattern under both cathode and anode electropolarity treatments.  相似文献   
132.
A hit to lead process to identify reversible, orally available ADP receptor (P2Y12) antagonists lead compounds is described. High throughput screening afforded 1. Optimization of 1, using parallel synthesis methods, a methyl scan to identify promising regions for optimization, and exploratory SAR on these regions, provided 22 and 23. Compound 23 is an orally available, competitive reversible antagonist (KB?=?94?nM for inhibition of ADP-induced platelet aggregation). It exhibits high metabolic stability in human, rat and dog liver microsomes and is orally absorbed. Although plasma level after oral dosing of 22 and 23 to rats is low, reasonable levels were achieved to merit extensive lead optimization of this structural class.  相似文献   
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The present study is aimed at the naphthalene degradation with and without biosurfactant produced from Pseudomonas aeruginosa isolated from oil-contaminated soil. The present study was carried out to isolate the bacterial strains for the naphthalene degradation and also for biosurfactant production. The isolated strains were screened for their ability to degrade the naphthalene by the methods of optimum growth rate test and for the production of biosurfactants by cetyltrimethylammonium bromide, blood agar medium, and thin-layer chromatography. The present study also focused on the effect of biosurfactant for the degradation of naphthalene by isolate-1. Two bacterial strains were isolated and screened, one for biodegradation and another for biosurfactant production. The second organism was identified as Pseudomonas aeruginosa by 16S rRNA analysis. The purified biosurfactant reduces the surface tension of water and also forms stable emulsification with hexadecane and kerosene. The end product of naphthalene degradation was estimated as salicylic acid equivalent by spectrophotometric method. The results demonstrated that Pseudomonas aeruginosa has the potential to produce biosurfactant, which enhances the biodegradation of naphthalene. The study reflects the potential use of biosurfactants for an effective bioremediation in the management of contaminated soils.  相似文献   
135.
Preliminary characterization of a biosurfactant-producing Azotobacter chroococcum isolated from marine environment showed maximum biomass and biosurfactant production at 120 and 132 h, respectively, at pH 8.0, 38°C, and 30‰ salinity utilizing a 2% carbon substrate. It grew and produced biosurfactant on crude oil, waste motor lubricant oil, and peanut oil cake. Peanut oil cake gave the highest biosurfactant production (4.6 mg/mL) under fermentation conditions. The biosurfactant product emulsified waste motor lubricant oil, crude oil, diesel, kerosene, naphthalene, anthracene, and xylene. Preliminary characterization of the biosurfactant using biochemical, Fourier transform infrared spectroscopy, and mass spectral analysis indicated that the biosurfactant was a lipopeptide with percentage lipid and protein proportion of 31.3:68.7.  相似文献   
136.
The focus of the present study was to compare ultrastructure in the midguts of larvae of the Hessian fly, Mayetiola destructor (Say), under different feeding regimens. Larvae were either fed on Hessian fly-resistant or -susceptible wheat, and each group was compared to starved larvae. Within 3 h of larval Hessian fly feeding on resistant wheat, midgut microvilli were disrupted, and after 6 h, microvilli were absent. The disruption in microvilli in larvae feeding on resistant wheat were similar to those reported for midgut microvilli of European corn borer, Ostrinia nubilasis (Hubner), larvae fed a diet containing wheat germ agglutinin. Results from the present ultrastructural study, coupled with previous studies documenting expression of genes encoding lectin and lectin-like proteins is rapidly up-regulated in resistant wheat to larval Hessian fly, are indications that the midgut is a target of plant resistance compounds. In addition, the midgut of the larval Hessian fly is apparently unique among other dipterans in that no peritrophic membrane was observed. Ultrastructural changes in the midgut are discussed from the prospective of their potential affects on the gut physiology of Hessian fly larvae and the mechanism of antibiosis in the resistance of wheat to Hessian fly attack.  相似文献   
137.
A modified fluorescein diacetate (FDA) assay has been compared with standard NCCLS broth macrodilution and broth microdilution methods for the detection of antifungal activity. The FDA assay was performed in a medium containing bacteriological peptone, NaCl, yeast extract and glucose (0.2%, 0.1%, 0.1% and 1% w/v, respectively) and buffered with 10 mM BES buffer. The MICs of amphotericin B, fluconazole, miconazole and flucytosine (representing three major classes of antifungal agents) obtained by the three methods were compared. The results obtained with the FDA assays correlated well with the NCCLS macrodilution method for MICs of amphotericin B, miconazole and fluconazole, but not for flucytosine. However, the MIC values of flucytosine obtained with the FDA assay were well within the quality control range for the two reference strains recommended by the NCCLS. The FDA assay described is an attractive alternative to the NCCLS methods for screening for antifungal agents, with the added advantage of objectivity of fluorescence measurement.  相似文献   
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Sample preparation in plant proteomics is tedious, requiring modifications depending on the type of tissue involved. Here, we describe a protein extraction protocol for both monocotyledonous (monocot) and dicotyledonous (dicot) species, which significantly improves the solubilization of total proteins. For example, we used the primary leaf tissue and seeds from rice, a cereal crop and genome model system. Total protein was first precipitated with trichloroacetic acid/acetone extraction buffer (TCAAEB) and subsequently solubilized with a modified O’Farrell lysis buffer (LB) containing thiourea and tris (LB-TT). Separation of total leaf proteins by two-dimensional gel electrophoresis (2-DGE) revealed improved solubilization, as determined by an increased number of spots detected with Coomassie brilliant blue (CBB) staining. In addition, the resolution was better than when LB-TT was used alone for protein extraction. Seed proteins could be extracted in LB-TT itself without the need for TCAAEB, which resulted in a highly insoluble precipitate. Our CBB-stained 2-D gel protein profiles also demonstrated the efficacy of this protocol for total protein extraction/solubilization from the dicot genome model (Arabidopsis), a dicot disease model (cucumber), and two other important monocot cereal crop models (maize and wheat). Moreover, this is the first report on generating a 2-D gel proteome profile for wheat crown and cucumber leaf tissues. Finally, as examples of proteome reference maps, we obtained silver nitrate-stained, large-format 2-D gels for rice leaf and wheat crown LB-TT solubilized proteins.  相似文献   
140.
Responses to a selective azaindole-based Rho kinase (ROCK) inhibitor (azaindole-1) were investigated in the rat. Intravenous injections of azaindole-1 (10-300 μg/kg), produced small decreases in pulmonary arterial pressure and larger decreases in systemic arterial pressure without changing cardiac output. Responses to azaindole-1 were slow in onset and long in duration. When baseline pulmonary vascular tone was increased with U46619 or L-NAME, the decreases in pulmonary arterial pressure in response to the ROCK inhibitor were increased. The ROCK inhibitor attenuated the increase in pulmonary arterial pressure in response to ventilatory hypoxia. Azaindole-1 decreased pulmonary and systemic arterial pressures in rats with monocrotaline-induced pulmonary hypertension. These results show that azaindole-1 has significant vasodilator activity in the pulmonary and systemic vascular beds and that responses are larger, slower in onset, and longer in duration when compared with the prototypical agent fasudil. Azaindole-1 reversed hypoxic pulmonary vasoconstriction and decreased pulmonary and systemic arterial pressures in a similar manner in rats with monocrotaline-induced pulmonary hypertension. These data suggest that ROCK is involved in regulating baseline tone in the pulmonary and systemic vascular beds, and that ROCK inhibition will promote vasodilation when tone is increased by diverse stimuli including treatment with monocrotaline.  相似文献   
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