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951.
952.
Ojha S Bharti S Sharma AK Rani N Bhatia J Kumari S Arya DS 《Indian journal of biochemistry & biophysics》2011,48(1):22-28
The cardioprotective potential of Inula racemosa root hydroalcoholic extract against isoproterenol-induced myocardial infarction was investigated in rats. The rats treated with isoproterenol (85 mg/kg, s.c.) exhibited myocardial infarction, as evidenced by significant (P < 0.05) decrease in mean arterial pressure, heart rate, contractility, relaxation along with increased left ventricular end diastolic pressure, as well as decreased endogenous myocardial enzymatic and non-enzymatic antioxidants. Isoproterenol also significantly (P < 0.05) induced lipid peroxidation and increased leakage of myocyte injury marker enzymes. Pretreatment with I. racemosa extract (50, 100 or 200 mg/kg per day, p.o.) for 21 consecutive days, followed by isoproterenol injections on days 19th and 20th significantly (P < 0.05) improved cardiac function by increasing the heart rate, mean arterial pressure, contractility and relaxation along with decreasing left ventricular end diastolic pressure. Pretreatment with I. racemosa also significantly (P < 0.05) restored the reduced form of glutathione and endogenous antioxidant enzymes superoxide dismutase, catalase, glutathione peroxidase from the heart, which were depleted after isoproterenol administration. In addition to restoration of antioxidants, I. racemosa significantly (P < 0.05) inhibited lipid peroxidation and prevented the leakage of myocytes specific marker enzymes creatine phosphokinase-MB and lactate dehydrogenase from the heart. Thus, it is concluded that I. racemosa protects heart from isoproterenol-induced myocardial injury by reducing oxidative stress and modulating hemodynamic and ventricular functions of the heart. Present study findings demonstrate the cardioprotective effect of I. racemosa and support the pharmacological relevance of its use and cardioprotection mechanism in ischemic heart disease as well as substantiate its traditional claim. 相似文献
953.
954.
The present study firstly reports the cytological and molecular marker assisted differentiation of isomorphic population of
Gracilaria
corticata (J. Agardh) with inter and intra-phasic genetic diversity analysis using ISSR markers. The genetic diversity of inbreeding
population of G. corticata as determined in terms of percentage of polymorphic loci (PPL), average heterozygosity (He) and Shannon’s Weaver index (I)
were 59.80, 0.59 and 1.21, respectively. The inter-phasic pair-wise average polymorphism were found to be 31.6% between male
and female, 24.0% in male and tetrasporophyte and 25.3% in female and tetrasporophyte. The intra-phasic average polymorphisms
were calculated as a maximum of 5.5% between females, 4.2% between males and the lowest 2.4% between tetrasporophytes. The
primer 10 generated a marker of 800 bp specific to male and 650 bp to female gametophyte, while the primer 17 generated a
marker of 2,500 bp specific to tetrasporophyte. Both the UPGMA based dendrogram and PCA analysis clustered all the three life
phases differentially as distinct identity. Cytological analysis by chromosome count revealed 24 chromosomes in both haploid
male and female gametophytes (N) and 48 for diploid (2 N) tetrasporophyte further confirming their genetic distinctness. The
life phase specific markers reported in this study could be of help in breeding programmes where differentiation of life phases
at the early developmental stages is crucial. 相似文献
955.
956.
Background
Difference in the capacity of xenobiotic metabolising enzymes might be an important factor in genetic susceptibility to cancer.Methods
A case control study involving forty one gastric cancer patients and one hundred and thirty controls was carried out to determine the frequency of GSTM1 and GSTT1 null genotypes. The frequency of GSTM1 and GSTT1 null genotype was observed by carrying out multiplex PCR.Results
There was no difference in the frequencies of the GSTM1 and GSTT1 null and the combined GSTM1 and GSTT1 null genotype between patients and control.Conclusions
Our data suggest that GSTM1 and GSTT1 status may not influence the risk of developing gastric cancer. 相似文献957.
Extracellular secretion of lignin peroxidase from Pycnoporus sanguineus MTCC-137 in the liquid culture growth medium amended with lignin containing natural sources has been shown. The maximum secretion of lignin peroxidase has been found in the presence of saw dust. The enzyme has been purified to homogeneity from the culture filtrate of the fungus using ultrafiltration and anion exchange chromatography on DEAE-cellulose. The purified lignin peroxidase gave a single protein band in sodium dodecylsulphate polyacrylamide gel electrophoresis corresponding to the molecular mass 40 kDa. The K(m)(, kcat) and k(cat)/K(m) values of the enzyme using veratryl alcohol and H2O2 as the substrate were 61 microM, 2.13 s(-1), 3.5 x 10(4) M(-1) s(-1) and 71 microM, 2.13 s(-1), 3.0 x 10(4) M(-1) s(-1) respectively at the optimum pH of 2.5. The temperature optimum of the enzyme was 25 degrees C. 相似文献
958.
Patel RV Kumari P Chikhalia KH 《Zeitschrift für Naturforschung. C, Journal of biosciences》2011,66(7-8):345-352
A series of 1,3,5-triazine derivatives that contain 4-amino-2-trifluoromethyl-benzonitrile, 8-hydroxyquinoline, and different piperazines as substituents at the carbon atoms of the triazine ring have been synthesized by a simple and efficient synthetic protocol. The chemical structures of the compounds were elucidated with the aid of IR, 1H NMR and 13C NMR spectroscopy, and elemental analysis. The antimicrobial activity of the compounds was tested against seven bacteria (Staphylococcus aureus MTCC 96, Bacillus cereus MTCC 619, Escherichia coli MTCC 739, Pseudomonas aeruginosa MTCC 741, Klebsiella pneumoniae MTCC 109, Salmonella typhi MTCC 733, Proteus vulgaris MTCC 1771) and four fungi (Aspergillus niger MTCC 282, Aspergillus fumigatus MTCC 343, Aspergillus clavatus MTCC 1323, Candida albicans MTCC 183). The results indicate that some of the novel s-triazines have noteworthy activity in minimum inhibitory concentration as well as agar diffusion tests. 相似文献
959.
This study was designed to determine whether: (1) hypoxia could directly affect ROS production in isolated mitochondria and mitochondrial complex III from pulmonary artery smooth muscle cells (PASMCs) and (2) Rieske iron-sulfur protein in complex III might mediate hypoxic ROS production, leading to hypoxic pulmonary vasoconstriction (HPV). Our data, for the first time, demonstrate that hypoxia significantly enhances ROS production, measured by the standard ROS indicator dichlorodihydrofluorescein/diacetate, in isolated mitochondria from PASMCs. Studies using the newly developed, specific ROS biosensor pHyPer have found that hypoxia increases mitochondrial ROS generation in isolated PASMCs as well. Hypoxic ROS production has also been observed in isolated complex III. Rieske iron-sulfur protein silencing using siRNA abolishes the hypoxic ROS formation in isolated PASM complex III, mitochondria, and cells, whereas Rieske iron-sulfur protein overexpression produces the opposite effect. Rieske iron-sulfur protein silencing inhibits the hypoxic increase in [Ca(2+)](i) in PASMCs and hypoxic vasoconstriction in isolated PAs. These findings together provide novel evidence that mitochondria are the direct hypoxic targets in PASMCs, in which Rieske iron-sulfur protein in complex III may serve as an essential, primary molecule that mediates the hypoxic ROS generation, leading to an increase in intracellular Ca(2+) in PASMCs and HPV. 相似文献
960.