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291.
Protective Effects of 7‐Hydroxycoumarin on Dyslipidemia and Cardiac Hypertrophy in Isoproterenol‐Induced Myocardial Infarction in Rats 下载免费PDF全文
Govindan Sangaran Jagadeesh M. F. Nagoor Meeran Palanisamy Selvaraj 《Journal of biochemical and molecular toxicology》2016,30(3):120-127
This study evaluates the protective effects of 7‐hydroxycoumarin (7‐HC) on dyslipidemia and cardiac hypertrophy in isoproterenol (ISO) induced myocardial infarction (MI) in rats. Rats were pre‐ and co treated with 7‐HC (16 mg/kg) daily for 8 days. ISO (100 mg/kg) was subcutaneously injected into rats on seventh and eighth days to induce MI. Increased activity/levels of serum creatine kinase‐MB (CK‐MB), troponin‐T, plasma lipid peroxidation products, and altered levels of lipids in the serum and heart and serum lipoproteins were noted in ISO‐induced rats. ISO‐induced myocardial infarcted rats revealed increased hypertrophy (cardiac and left ventricular) and hepatic 3‐hydroxyl 3‐methylglutaryl‐coenzyme‐A reductase (HMG‐CoA reductase) activity. Pre and cotreatment with 7‐HC revealed significant protective effects on all the biochemical parameters evaluated. The in vitro study demonstrated its free radical scavenging property. Thus, 7‐HC protects ISO‐induced MI in rats by its free radical scavenging and antihyperlipidaemic and antihypertrophic properties. 相似文献
292.
293.
N. P. Gopalan 《Bulletin of mathematical biology》1981,43(5):563-577
This paper deals with the pulsatile blood flow in the lung alveolar sheets by idealizing each of them as a channel covered
by porous media. As the blood flow in the lung is of low Reynolds number, a creeping flow is assumed in the channel. The analytical
and numerical results for the velocity and pressure distribution in the porous medium are presented. The effect of an imposed
slip condition is also studied. Comparisons with the corresponding results for the steady-state case are made at the end. 相似文献
294.
The subunits of human placental milli calcium activated neutral proteinase and micro calcium activated neutral proteinase
have been separated by partial denaturation with urea followed by molecular sieving, with a recovery of 82–91% of activity.
The separated subunits were homogeneous, as judged by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. Their molecular
sizes, catalytic activities and sulphydryl contents suggest that both the subunits of these two calcium activated neutral
proteinases are distinct. The subunits were highly specific and could not be interchanged. Both the subunits of micro calcium
activated neutral proteinase were catalytically active whereas only the 80 k subunit of milli calcium activated neutral proteinase
was active. 30 k subunit of milli calcium activated neutral proteinase has a regulatory role since maximum activity of the
80 k subunit was elicited only in its presence. Activity of the reassociated subunits indicated that interaction is essential
for the expression of optimum activity. Interaction of subunits rendered the enzymes less susceptible to inhibition by endogenous
calcium activated neutral proteinase inhibitor. 相似文献
295.
V Gopalan D J Vander Jagt D P Libell R H Glew 《The Journal of biological chemistry》1992,267(14):9629-9638
This study establishes that guinea pig liver cytosolic beta-glucosidase generates a common glucosyl-enzyme intermediate from a variety of aryl beta-D-glucoside substrates and that the intermediate can react with various acceptors to form distinct products at rates which are dependent on the structure, nucleophilicity, and concentration of the acceptor. Specifically, we demonstrate that water and linear alkanols will react with the glucosyl-enzyme intermediate to form D-glucose and alkyl-beta-D-glucoside (e.g. octyl-beta-D-glucoside), respectively. The rate of alcoholysis is 24-fold greater than the rate of hydrolysis of the glucosyl-enzyme intermediate and accounts for the increase in steady-state rate of substrate disappearance in the presence of alcohols. In addition, the substrate molecule itself (e.g. p-nitrophenyl-beta-D-galactoside (pNP-Gal)) can serve as an acceptor in the transglycosylation reaction, thereby enabling the enzyme to synthesize disaccharide glycosides (e.g. pNP-beta-Gal(6----1)beta-Gal). The transglycosylation data point to the presence of two hydrophobic subsites in the active site of the cytosolic beta-glucosidase. These data support a model in which the cytosolic beta-glucosidase binds an acceptor and a glycosyl donor simultaneously within its catalytic center and efficiently catalyzes the transfer of a sugar residue from the donor to the acceptor. 相似文献
296.
Rice is the staple food crop of more than 60% of the population of the world. This crop suffers from blast disease caused by Magnaporthe oryzae. Information on the mating-type allele distribution and diversity of the pathogen population for the state of Karnataka, India is scanty. With this background, a total of 72 isolates of M. oryzae from rice in different districts of Karnataka were examined for identifying sexual mating alleles MAT1, MAT2 and understanding the genetic diversity based on DNA fingerprint of pot2, an inverted repeat transposon. Among 72 isolates, 44 isolates belonged to MAT1 type (male fertile) and 28 isolates were of MAT2 (female fertile) and there were no hermaphrodite isolates. In a given geographical location, only one mating type was identified. Results revealed that the isolates obtained from these regions are not sexually fertile showing predominant asexual reproduction. Hence, genetic variation observed in the pathogen may be mainly because of high copy number of transposons. A high copy number transposon, namely Pot2, was selected in our study to detect genetic diversity of the pathogen. Pot2 rep-PCR DNA fingerprinting profile showed 27 polymorphic bands with bands ranging in size from 0.65 to 4.0 kb and an average of 10 to 14 bands per isolate. Five distinct clusters were formed with two major, two minor, and one outlier. Clusters 4 and 5 are further subdivided into three sub-clusters. Some of the isolates belonging to clusters 3, 4, and 5 are interlinked as these locations are close to one another sharing common geographical parameters and boundaries. This knowledge on the sexual behavior and genetic diversity of M. oryzae is important with respect to breeding for disease resistance. 相似文献
297.
Background
Transforming growth factor beta (TGF-β) is a multipurpose cytokine, which plays a role in many cellular functions such as proliferation, differentiation, migration, apoptosis, cell adhesion and regulation of epithelial to mesenchymal transition. Despite many studies having observed the effect that TGF-β plays in colorectal cancer, its role in the colorectal stem cell population has not been widely observed.Method
This systematic review will analyse the role of TGF-β in the stem cell population of colorectal cancer.Results
The effects on the stem cell phenotype are through the downstream proteins involved in activation of the TGF-β pathway. Its involvement in the initiation of the epithelial to mesenchymal transition (EMT), the effect of colorectal invasion and metastasis regulated through the Smad protein involvement in the EMT, initiation of angiogenesis, promotion of metastasis of colorectal cancer to the liver and its ability to cross-talk with other pathways.Conclusion
TGF-β is a key player in angiogenesis, tumour growth and metastasis in colon cancer. 相似文献298.
Katherine Ting-Wei Lee Vinod Gopalan Farhadul Islam Riajul Wahab Afraa Mamoori Cu-tai Lu Robert Anthony Smith Alfred King-yin Lam 《European journal of cell biology》2018,97(3):230-241
GAEC1 (gene amplified in oesophageal cancer 1) is a transforming oncogene with tumorigenic potential observed in both oesophageal squamous cell carcinoma and colorectal cancer. Nonetheless, there has been a lack of study done on this gene to understand how this gene exert its oncogenic properties in cancer. This study aims to identify novel mutation sites in GAEC1. To do so, seventy-nine matched colorectal cancers were tested for GAEC1 mutation via Sanger sequencing. The mutations noted were investigated for the correlations with the clinicopathological parameters of the patients with the cancer. Additionally, GAEC1 copy number aberration (CNA), mRNA and protein expression were determined with the use of droplet digital (dd) polymerase chain reaction (PCR), real-time PCR and Western blot (confirmed with immunofluorescence analysis). GAEC1 mutation was noted in 8.8% (n?=?7/79) of the cancer tissues including one missense mutation, four loss of heterozygosity (LOH) and two substitutions. These mutations were significantly associated with cancer perforation (p?=?0.021). GAEC1 mutation is frequently associated with increased GAEC1 protein expression. Nevertheless, GAEC1 mRNA and protein are only weakly associated. Taken together, GAEC1 mutation affects GAEC1 expression and is associated with poorer clinical outcomes. This further strengthens the role of GAEC1 as an oncogene. 相似文献
299.
Automation aided optimization of cloning,expression and purification of enzymes of the bacterial sialic acid catabolic and sialylation pathways enzymes for structural studies 下载免费PDF全文
Sneha Bairy Lakshmi Narayanan Gopalan Thanuja Gangi Setty Sathya Srinivasachari Lavanyaa Manjunath Jay Prakash Kumar Sai R Guntupalli Sucharita Bose Vinod Nayak Swagatha Ghosh Nitish Sathyanarayanan Rhawnie Caing‐Carlsson Weixiao Yuan Wahlgren Rosmarie Friemann S. Ramaswamy Muniasamy Neerathilingam 《Microbial biotechnology》2018,11(2):420-428
The process of obtaining a well‐expressing, soluble and correctly folded constructs can be made easier and quicker by automating the optimization of cloning, expression and purification. While there are many semiautomated pipelines available for cloning, expression and purification, there is hardly any pipeline that involves complete automation. Here, we achieve complete automation of all the steps involved in cloning and in vivo expression screening. This is demonstrated using 18 genes involved in sialic acid catabolism and the surface sialylation pathway. Our main objective was to clone these genes into a His‐tagged Gateway vector, followed by their small‐scale expression optimization in vivo. The constructs that showed best soluble expression were then selected for purification studies and scaled up for crystallization studies. Our technique allowed us to quickly find conditions for producing significant quantities of soluble proteins in Escherichia coli, their large‐scale purification and successful crystallization of a number of these proteins. The method can be implemented in other cases where one needs to screen a large number of constructs, clones and expression vectors for successful recombinant production of functional proteins. 相似文献
300.
(−)-Deprenyl, 0.05, 1.0, 2.0, and 10.0 mg/kg body weight, was administered intraperitonially to Wistar rats for 30 days. The
activity of acetylcholinesterase, and monoamine oxidase A and B were assayed in different brain regions. After the experimental
period acetyl cholinesterase activity was found to be significantly increased in frontal cortex [P<0.001] and hippocampus
[P<0.001] but not in striatum and brainstem at 0.1, 1.0, and 2.0 mg/kg dose, the maximum increase being at 0.1 mg/kg dose.
Monoamine oxidase B activity was inhibited by more than 90% at 1.0, 2.0, and 10.0 mg/kg dose while 0.05 and 0.1 dose inhibited
only about 55% and 70% respectively. Monoamine oxidase A activity was inhibited to more than 70% at 1.0 mg dose and to more
than 90% at 2.0 and 10.0 mg/kg dose. At 0.05 and 0.1 mg/kg dose monoamine oxidase A activity was not significantly altered. 相似文献