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81.
Marion Laig Michael Pape Joachim Hundrieser Gebhard Flatz Torpong Sanguansermsri B. M. Das Ranjan Deka Puangrat Yongvanit Naret Mularlee 《Human genetics》1990,84(2):188-190
Summary The distribution of the hemoglobin Constant Spring (Hb CS) gene in eight populations in Southeast Asia (including Assam) was determined using oligonucleotide hybridization. Hb CS was absent in two Assamese populations with a high prevalence of Hb E. The Hb CS gene frequency was 0.033 in northern Thailand and near 0.01 in central Thailand and Cambodia. High frequencies, between 0.05 and 0.06, were observed in northeastern Thailand. The present data and a similar study in Laotians suggest that the Lao-speaking populations of the Mekong River basin in northeastern Thailand and Laos have the highest frequencies of the Hb CS gene in Southeast Asia. 相似文献
82.
Subbarayan Sarathbabu Ranjan Jyoti Sarma H. Lalhruaitluanga Devadasan Velmurugan 《Journal of biomolecular structure & dynamics》2020,38(12):3474-3488
AbstractPierisin-5 is a DNA dependent ADP ribosyltransferase (ADRT) protein from the larvae of Indian cabbage white butterfly, Pieris canidia. Interestingly, Pierisin-5 ADP-ribosylates the DNA as a substrate, but not the protein and subsequently persuades apoptotic cell death in human cancer cells. This has led to the investigation on the DNA binding activity of Pierisin-5 using in vitro and in silico approaches in the present study. However, both the structure and the mechanism of ADP-ribosylation of pierisin-5 are unknown. In silico modeled structure of the N-terminal ADRT catalytic domain interacted with the minor groove of B-DNA for ribosylation with the help of β-NAD+ which lead to a structural modification in DNA (DNA adduct). The possible interaction between calf thymus DNA (CT-DNA) and purified pierisin-5 protein was studied through spectral–spatial studies and the blue shift and hyperchromism in the UV–Visible spectra was observed. The DNA adduct property of pierisin-5 protein was validated by in vitro cytotoxic assay on human gastric (AGS) cancer cell lines. Our study is the first report of the mechanism of DNA binding property of pierisin-5 protein which leads to the induction of cytotoxicity and apoptotic cell death against cancer cell lines.Communicated by Ramaswamy H. Sarma 相似文献
83.
Ashish K. Mehta Yogendra Bhati Chakra D. Tripathi Krishna K. Sharma 《Neurochemical research》2014,39(8):1433-1439
Despite immense advances in the treatment strategies, management of neuropathic pain remains unsatisfactory. Piracetam is a prototype of nootropic drugs, used to improve cognitive impairment. The present study was designed to investigate the effect of piracetam on peripheral neuropathic pain in rats. Neuropathic pain was induced by the chronic constriction injury of the sciatic nerve. Following this, piracetam was intraperitoneally administered for 2 weeks in doses of 50, 100 and 200 mg/kg, and pain was assessed by employing the behavioural tests for thermal hyperalgesia (hot plate and tail flick tests) and cold allodynia (acetone test). After the induction of neuropathic pain, significant development of thermal hyperalgesia and cold allodynia was observed. The administration of piracetam (50 mg/kg) did not have any significant effect on all the behavioural tests. Further, piracetam (100 mg/kg) also had no effect on the hot plate and tail flick tests; however it significantly decreased the paw withdrawal duration in the acetone test. Piracetam in a dose of 200 mg/kg significantly modulated neuropathic pain as observed from the increased hot plate and tail flick latencies, and decreased paw withdrawal duration (in acetone test). Therefore, the present study suggests the potential use of piracetam in the treatment of neuropathic pain, which merits further clinical investigation. 相似文献
84.
S.P. Patel G. Ranjan V.S. Patel 《International journal of biological macromolecules》1987,9(6):314-320
The rheological properties of aqueous solutions of guar gum (GG) and hydroxyethyl guar gum (HEG) have been investigated. The flow properties of these polysaccharide solutions were studied at the shear rate in the range 1.5–1310s−1 using a Rheotest-2 viscometer. The flow of these polysaccharide solutions was described by equation of state based on Cross model. The basic rheological parameters, like zero shear rate viscosity (ηo), elasticity modulus (Go) and relaxation time (glo) were calculated using simple and established relations. Master viscosity curves indicated that the molecular weight distribution of native guar gum has been changed by hydroxyethylation under specified reaction conditions. The effect of concentration and temperature on ηo and λo has been studied, and the relations among these were established by simple equations. 相似文献
85.
Ashish Sharma Babita Patni Deepti Shankhdhar S. C. Shankhdhar 《Physiology and Molecular Biology of Plants》2013,19(1):11-20
Availability of Zn to plant is hampered by its immobile nature and adverse soil conditions. Thus, Zn deficiency is observed even though high amount is available in soil. Root-shoot barrier, a major controller of zinc transport in plant is highly affected by changes in the anatomical structure of conducting tissue and adverse soil conditions like pH, clay content, calcium carbonate content, etc. Zn deficiency results in severe yield losses and in acute cases plant death. Zn deficiency in edible plant parts results in micronutrient malnutrition leading to stunted growth and improper sexual development in humans. To overcome this problem several strategies have been used to enrich Zn availability in edible plant parts, including nutrient management, biotechnological tools, and classical and molecular breeding approaches. 相似文献
86.
David F. Stowe Ashish K. Gadicherla Yifan Zhou Mohammed Aldakkak Qunli Cheng Wai-Meng Kwok Ming Tao Jiang James S. Heisner MeiYing Yang Amadou K.S. Camara 《生物化学与生物物理学报:生物膜》2013,1828(2):427-442
We tested if small conductance, Ca2 +‐sensitive K+ channels (SKCa) precondition hearts against ischemia reperfusion (IR) injury by improving mitochondrial (m) bioenergetics, if O2‐derived free radicals are required to initiate protection via SKCa channels, and, importantly, if SKCa channels are present in cardiac cell inner mitochondrial membrane (IMM). NADH and FAD, superoxide (O2?), and m[Ca2 +] were measured in guinea pig isolated hearts by fluorescence spectrophotometry. SKCa and IKCa channel opener DCEBIO (DCEB) was given for 10 min and ended 20 min before IR. Either TBAP, a dismutator of O2?, NS8593, an antagonist of SKCa isoforms, or other KCa and KATP channel antagonists, were given before DCEB and before ischemia. DCEB treatment resulted in a 2-fold increase in LV pressure on reperfusion and a 2.5 fold decrease in infarct size vs. non-treated hearts associated with reduced O2? and m[Ca2 +], and more normalized NADH and FAD during IR. Only NS8593 and TBAP antagonized protection by DCEB. Localization of SKCa channels to mitochondria and IMM was evidenced by a) identification of purified mSKCa protein by Western blotting, immuno-histochemical staining, confocal microscopy, and immuno-gold electron microscopy, b) 2-D gel electrophoresis and mass spectroscopy of IMM protein, c) [Ca2 +]‐dependence of mSKCa channels in planar lipid bilayers, and d) matrix K+ influx induced by DCEB and blocked by SKCa antagonist UCL1684. This study shows that 1) SKCa channels are located and functional in IMM, 2) mSKCa channel opening by DCEB leads to protection that is O2? dependent, and 3) protection by DCEB is evident beginning during ischemia. 相似文献
87.
Sureka Bollepalli Lawrence M. Dolan Ranjan Deka Lisa J. Martin 《Obesity (Silver Spring, Md.)》2010,18(10):1959-1963
The prevalence of obesity continues to increase significantly, with the largest rise in the African‐American adolescents. Genetic contributions to obesity are being identified with the advent of genome‐wide association studies (GWAS). Specifically, variants of the fat mass and obesity associated (FTO) gene have been associated with obesity in populations of European descent. The studies in African Americans have been inconclusive. To further evaluate the association of the FTO gene and adiposity in African Americans, we genotyped 47 single‐nucleotide polymorphisms (SNPs), including seven SNPs previously reported to be significant in the literature in a cohort consisting of 561 non‐Hispanic white and 497 African‐American individuals. Analysis of our data showed 17 SNPs to be associated with BMI Z‐score (BMI‐Z) in our study population. The strongest association was found in the African Americans. The most significant SNP was rs8057044, which was associated with BMI‐Z in the African Americans (P = 0.00054). SNP rs9939609 was found to be significant in the non‐Hispanic white population (P = 0.028). Our data confirm the association between FTO and adiposity suggesting that FTO is a childhood obesity susceptibility gene. Our data also identify a novel SNP of the FTO gene (rs8057044) that is associated with measures of adiposity in the African‐American population. 相似文献
88.
Curcumin is a natural polyphenolic compound having an antiproliferative property, which recent evidence suggests is due to its ability to induce apoptosis. However, the molecular mechanisms through which curcumin induces apoptosis are not fully understood. Here, we report that the curcumin-induced apoptosis is mediated through the impairment of the ubiquitin-proteasome system. Exposure of curcumin to the mouse neuro 2a cells causes a dose-dependent decrease in proteasome activity and an increase in ubiquitinated proteins. Curcumin exposure also decreases the turnover of the destabilized enhanced green fluorescence protein, a model substrate for proteasome and cellular p53 protein. Like other proteasome inhibitors, curcumin targets proliferative cells more efficiently than differentiated cells and induces apoptosis via mitochondrial pathways. Addition of curcumin to neuro 2a cells induces a rapid decrease in mitochondrial membrane potential and the release of cytochrome c into cytosol, followed by activation of caspase-9 and caspase-3. 相似文献
89.
90.