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461.
In this study we used liver mitochondrial and microsomal fraction from rats pretreated with seaweed Ulva lactuca polysaccharide extract (ULP - 200 mg/kg body weight, daily for 21 days, oral gavage) on D-Galactosamine (500 mg/kg body weight, intraperitoneally) challenge. Effectiveness of ULP was determined based on functional status of trichloro acetic acid (TCA), urea cycle, and microsomal enzymes. The composition of sulfate polysaccharide content such as total sugars, sulfate and uronic acid were examined. In addition the fine ultra structural changes were examined using electron microscopy (EM). We observed significant (p < 0.001) mitochondrial and microsomal abnormalities during liver damage by D-Galactosamine, consequently altering enzymes of energy metabolism. Electron microscopy of D-Galactosamine intoxicated rat liver tissue revealed the swelling and loss of mitochondrial cristae. Conversely the rats pretreated with ULP against D-Galactosamine challenge prevented (p < 0.05) the significant abnormality of TCA, microsomal enzymes and severity of mitochondria as observed in EM study in rats injected with D-Galactosamine alone. However no effective prevention was observed in urea cycle enzymes among D-Galactosamine and treatment group rats. These results showed the effectiveness of ULP in stabilizing the functional status of mitochondrial and microsomal membrane which might be due to the presence of sulfated polysaccharide that could prevented the oxidative stress induced by D-Galactosamine intoxication.  相似文献   
462.
Shigella and Salmonella kill host cells and trigger inflammatory responses by mechanisms that are not fully understood. The goal of this review is to reevaluate key observations reported over the past 15 years and, whenever possible, to provide a chronological perspective as to how our understanding of the pathways by which Shigella and Salmonella kill host cells has evolved.  相似文献   
463.

Background  

Streptomycin (SM) is a broad spectrum antibiotic and is an important component of any anti-tuberculosis therapy regimen. Several mechanisms have been proposed to explain the emergence of resistance but still our knowledge is inadequate. Proteins form a very complex network and drugs are countered by their modification/efflux or over expression/modification of targets. As proteins manifest most of the biological processes, these are attractive targets for developing drugs, immunodiagnostics or therapeutics. The aim of present study was to analyze and compare the protein profile of whole cell extracts from Mycobacterium tuberculosis clinical isolates susceptible and resistant to SM.  相似文献   
464.
Azines derived from substituted phenacyl aryl/cyclohexyl sulfide on treatment with excess phosphorous oxychloride in N,N-dimethylformamide have been found to yield two isomeric pyrazoles in each case. A plausible mechanism has been suggested for the formation of the products. The antimycobacterial activity of the isomeric compounds has been tested against Mycobacterium tuberculosis (MTB).  相似文献   
465.
Ten novel 3,5-diaryl pyrazolines were synthesized and investigated for their monoamine oxidase (MAO) inhibitory property. All the molecules were found to be reversible and selective inhibitor for either one of the isoform (MAO-A or MAO-B). Further insights in the theoretical evaluation of the possible interactions between the compounds and monoamine oxidases (MAO-A or MAO-B) have been developed through docking studies. The theoretical values are in congruence with their experimental values.  相似文献   
466.
This article describes the syntheses and SAR of a series of imidazolopyrimidine derivatives, which are evaluated as inhibitors of PI3-Kinase (PI3 K) and mTOR. These compounds were found to be ATP competitive with good tumor cell growth inhibition, and suppression of pathway specific biomakers such as phosphorylation of Akt at T308.  相似文献   
467.
468.
A simple and rapid high performance liquid chromatographic method for determination of efavirenz in human plasma was developed. The method involved extraction of sample with ethyl acetate and analysis using a reversed-phase C(18) column (150 mm) with UV detection. The assay was linear from 0.0625 to 10.0 microg/ml. The method was specific for efavirenz estimation and the drug was stable in plasma up to one month at -20 degrees C. The average recovery of efavirenz from plasma was 101%. Due to its simplicity, the assay can be used for pharmacokinetic studies and therapeutic drug monitoring of efavirenz.  相似文献   
469.
Occurrence of widespread epizootics among larval and cultured shrimp has put on viable preventive approaches such as application of probiotics on a high priority in aquaculture. In the present study, four probiotics bacteria were isolated from marine fish and shrimp intestine based on the antagonistic activity and nonpathogenic to the host. The isolates of probiotics strains Streptococcus phocae PI80, Enterococcus faecium MC13, Lactococcus garvieae LC149, B49 and one commercial probiotics (ECOFORCE) were fed to post larvae of Penaeus monodon obtained from two different hatcheries to analyze the growth and protection against Vibrio harveyi and V. parahaemolyticus. Growth of P. monodon post larvae fed with probiotic strain S. phocae PI80 was significantly (P < 0.001) higher when compared with control and other three strains in both experiments. The treatment of post larvae with B49 reduced the growth as well as Specific growth rate. Among the three probiotic strains S. phocae PI80 and E. faecium MC13 have effectively inhibited the pathogens. In experiment I high survival (92%) were observed in S. phocae PI80 treated post larvae when challenged with Vibrio harveyi followed by E. faecium MC13 (84%), B49 (76%) and ECOFORCE (68%) but PI80 did not protect the post larvae in the same experiment when they were exposed to V. parahaemolyticus. The probiotic isolate of MC13 has protected the post larvae against V. parahaemolyticus when compared to other probiotics and control. Similarly in the second experiment feeding of S. phocae enhanced the survival of larvae when challenged with V. harveyi. The laboratory studies proved that bacterial probionts S. phocae and E. faecium isolated from shrimp and brackishwater fish has potential applications for controlling pathogenic vibriosis in shrimp culture.  相似文献   
470.
The synthesis and SAR of a series of 2,4-diamino-quinazoline derivatives as β-catenin/Tcf-4 inhibitors are described. This series was developed by modifying the initial lead 1, which was identified by screening of our compound library and found to inhibit the β-catenin/Tcf-4 pathway. Replacement of the biphenyl moiety in compound 1 with the N-phenylpiperidine-4-carboxamide chain as in 2, resulted in a number of new analogues, which are potent inhibitors of the β-catenin/Tcf-4 pathway. Compound such as 16k exhibited good cellular potency, solubility, metabolic stability and oral bioavailability.  相似文献   
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