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101.
Ayhan Dogukan Nurhan Sahin Mehmet Tuzcu Vijaya Juturu Cemal Orhan Muhittin Onderci James Komorowski Kazim Sahin 《Biological trace element research》2009,131(2):124-132
The present study was conducted to investigate the effects of chromium histidinate (CrHis) against experimentally induced
type II diabetes and on chromium (Cr), zinc (Zn), selenium (Se), manganese (Mn), iron (Fe), and copper (Cu) in serum, liver,
and kidney of diabetic rats. The male Wistar rats (n = 60, 8 weeks old) were divided into four groups. Group I received a standard diet (12% of calories as fat); group II were
fed standard diet and received CrHis (110 mcg CrHis/kg body weight per day); group III received a high-fat diet (HFD; 40% of calories as fat) for 2 weeks and then
were injected with streptozotocin (STZ) on day 14 (STZ, 40 mg/kg i.p.; HFD/STZ); group IV were treated as group III (HFD/STZ)
but supplemented with 110 mcg CrHis/kg body weight per day. The mineral concentrations in the serum and tissue were determined
by atomic absorption spectrometry. Compared to the HFD/STZ group, CrHis significantly increased body weight and reduced blood
glucose in diabetic rats (p < 0.001). Concentrations of Cr, Zn, Se, and Mn in serum, liver, and kidney of the diabetic rats were significantly lower
than in the control rats (p < 0.0001). In contrast, higher Fe and Cu levels were found in serum and tissues from diabetic versus the non-diabetic rats
(p < 0.001). Chromium histidinate supplementation increased serum, liver, and kidney concentrations of Cr and Zn both in diabetic
and non-diabetic rats (p < 0.001). Chromium supplementation increased Mn and Se levels in diabetic rats (p < 0.001); however, it decreased Cu levels in STZ-treated group (p < 0.001). Chromium histidinate supplementation did not affect Fe levels in both groups (p > 0.05). The results of the present study conclude that supplementing Cr to the diet of diabetic rats influences serum and
tissue Cr, Zn, Se, Mn, and Cu concentrations. 相似文献
102.
Yang He Xiulian Guo Ran Lu Bei Niu Vijaya Pasapula Pei Hou Feng Cai Ying Xu Fang Chen 《Plant Cell, Tissue and Organ Culture》2009,98(1):11-17
Callus browning is a typical feature of callus cultures derived from the hypocotyl of Jatropha curcas. Brown callus results in decreased regenerative ability, poor growth and even death. In this study, we investigated the effect
of browning on callus morphology and biochemical indices. Light microscopy and scanning electron microscopy showed striking
differences in callus morphology. During browning, chlorophylls and carotenoids concentrations decreased steadily. Polyphenol
oxidase (PPO) and peroxidase (POD) enzymatic activities patterns were similar during callus culture with a higher activity
level at week 3 compared to week 2 or later weeks. Grey relation degree analysis indicated that PPO played a more important
role than POD in enzymatic callus browning. Polyacrylamide gel electrophoresis results showed differences between browning
and non-browning callus. Gas chromatography–mass spectrometry results showed that saturated and unsaturated fatty acid quantities
differed significantly but there was little difference in fatty acid composition between non-browning and browning callus.
Differences in 17, 18.4 and 25 kDa protein concentrations were also observed in browning and non-browning callus using sodium
dodecyl sulfate–polyacrylamide gel electrophoresis. 相似文献
103.
Vijaya Ramachandran Thiruvengadam Arumugam Robert Langley Rosa F. Hwang Pablo Vivas-Mejia Anil K. Sood Gabriel Lopez-Berestein Craig D. Logsdon 《PloS one》2009,4(10)
Background
Adrenomedullin (AM) is highly expressed in pancreatic cancer and stimulates pancreatic cancer cells leading to increased tumor growth and metastasis. The current study examines the role of specific AM receptors on tumor and cells resembling the tumor microenvironment (human pancreatic stellate - HPSC, human umbilical vein – HUVEC and mouse lung endothelial cells - MLEC).Methods and Findings
AM receptors ADMR and CRLR were present in HPSC, HUVEC and MLECs while PDAC cells possessed only ADMR receptors as assessed by RT-PCR and western blotting. All cell lines expressed and secreted AM as indicated by ELISA. The growth of each of the cell lines was stimulated by exogenous AM and inhibited by the antagonist AMA. AM also stimulated in vitro angiogenesis assessed by polygon formation of endothelial cell lines. SiRNA-mediated silencing of ADMR, but not CRLR, reduced basal growth of all cells examined and reduced polygon formation of endothelial cells in vitro. Orthotopic tumors developed with shADMR bearing cancer cells had dramatically reduced primary tumor volume (>90%) and lung and liver metastasis compared to shControl bearing cells. To validate ADMR as a potential therapeutic target, in vivo studies were conducted using neutral nanoliposomes to systemically deliver human siRNA to ADMR to silence human cancer cells and mouse siRNA to ADMR to silence mouse tumor stromal cells. Systemic silencing of both human and mouse ADMR had no obvious adverse effects but strongly reduced tumor development.Conclusion
ADMR mediates the stimulatory effects of AM on cancer cells and on endothelial and stellate cells within the tumor microenvironment. These data support the further development of ADMR as a useful target treatment of pancreatic cancer. 相似文献104.
Flaviviral replication is believed to be exclusively cytoplasmic, occurring within virus-induced membrane-bound replication complexes in the host cytoplasm. Here we show that a significant proportion (20%) of the total RNA-dependent RNA polymerase (RdRp) activity from cells infected with West Nile virus, Japanese encephalitis virus (JEV), and dengue virus is resident within the nucleus. Consistent with this, the major replicase proteins NS3 and NS5 of JEV also localized within the nucleus. NS5 was found distributed throughout the nucleoplasm, but NS3 was present at sites of active flaviviral RNA synthesis, colocalizing with NS5, and visible as distinct foci along the inner periphery of the nucleus by confocal and immunoelectron microscopy. Both these viral replicase proteins were also present in the nuclear matrix, colocalizing with the peripheral lamina, and revealed a well-entrenched nuclear location for the viral replication complex. In keeping with this observation, antibodies to either NS3 or NS5 coimmunoprecipitated the other protein from isolated nuclei along with newly synthesized viral RNA. Taken together these data suggest an absolute requirement for both of the replicase proteins for nucleus-localized synthesis of flavivirus RNA. Thus, we conclusively demonstrate for the first time that the host cell nucleus functions as an additional site for the presence of functionally active flaviviral replicase complex. 相似文献
105.
T. Vijaya Lakshmi Y. Varalaxmi S. K. Yadav M. Maheswari 《Russian Journal of Plant Physiology》2017,64(6):889-898
Antioxidative enzyme activities and their isozyme patterns under water-deficit, salinity, high and low temperature stresses were studied in the seedlings of Pennisetum glaucum (L.) R.Br. It was observed that under water-deficit stress glutathione reductase (GR) was the key enzyme while in case of high temperature stress, GR along with catalase played a major role. Superoxide dismutase was found to be the main enzyme under low temperature stress. Co-ordinated higher expression of all the antioxidative enzymes was observed under salt stress. This study revealed the operation of different enzymatic antioxidative mechanisms under various abiotic stresses that will aid in understanding the metabolic basis of stress tolerance in pearl millet. 相似文献
106.
Zinc pyrithione salvages reperfusion injury by inhibiting NADPH oxidase activation in cardiomyocytes
Kasi V Bodiga S Kommuguri UN Sankuru S Bodiga VL 《Biochemical and biophysical research communications》2011,(2):270-275
Zinc pyrithione (ZPT), has a strong anti-apoptotic effect when administered just before reperfusion. Because oxidative stress has been proposed to contribute to myocardial reperfusion injury, we tested whether ZPT can reduce the production of reactive oxygen species during reoxygenation in cultured neonatal rat cardiac myocytes and evaluated the role of NADPH oxidase in hypoxia/reoxygenation (H/R) injury. The cells were subjected to 8 h of simulated ischemia, followed by either 30 min or 16 h of reoxygenation. ZPT when started just before reoxygenation significantly reduced superoxide generation, LDH release and improved cell survival compared to H/R. Attenuation of the ROS production by ZPT paralleled its capacity to prevent pyknotic nuclei formation. In addition, ZPT reversed the H/R-induced expression of NOX2 and p47phox phosphorylation indicating that ZPT directly protects cardiomyocytes from reperfusion injury by a mechanism that attenuates NADPH oxidase mediated intracellular oxidative stress. 相似文献
107.
Maize and grain sorghum seeds were sown in pots and grown for 39 days in sunlit controlled-environment chambers at 360 (ambient) and 720 (double-ambient, elevated) μmol mol−1 carbon dioxide concentrations [CO2]. Canopy net photosynthesis (PS) and evapotranspiration (TR) was measured throughout and summarized daily from 08:00 to 17:00 h Eastern Standard Time. Irrigation was withheld from matched pairs of treatments starting on 26 days after sowing (DAS). By 35 DAS, cumulative PS of drought-stress maize, compared to well-watered plants, was 41% lower under ambient [CO2] but only 13% lower under elevated [CO2]. In contrast, by 35 DAS, cumulative PS of drought-stress grain sorghum, compared to well-watered plants, was only 9% lower under ambient [CO2] and 7% lower under elevated [CO2]. During the 27-35 DAS drought period, water use efficiency (WUE, mol CO2 Kmol−1 H2O), was 3.99, 3.88, 5.50, and 8.65 for maize and 3.75, 4.43, 5.26, and 9.94 for grain sorghum, for ambient-[CO2] well-watered, ambient-[CO2] stressed, elevated-[CO2] well-watered and elevated-[CO2] stressed plants, respectively. Young plants of maize and sorghum used water more efficiently at elevated [CO2] than at ambient [CO2], especially under drought. Reductions in biomass by drought for young maize and grain sorghum plants were 42 and 36% at ambient [CO2], compared to 18 and 14% at elevated [CO2], respectively. Results of our water stress experiment demonstrated that maintenance of relatively high canopy photosynthetic rates in the face of decreased transpiration rates enhanced WUE in plants grown at elevated [CO2]. This confirms experimental evidence and conceptual models that suggest that an increase of intercellular [CO2] (or a sustained intercellular [CO2]) in the face of decreased stomatal conductance results in relative increases of growth of C4 plants. In short, drought stress in C4 crop plants can be ameliorated at elevated [CO2] as a result of lower stomatal conductance and sustaining intercellular [CO2]. Furthermore, less water might be required for C4 crops in future higher CO2 atmospheres, assuming weather and climate similar to present conditions. 相似文献
108.
Ravikumar G Raje Urs S Vijaya Prakash NB Rao CG Vardhana KV 《Journal of invertebrate pathology》2011,107(3):193-197
We have developed a novel PCR-based assay for individual and simultaneous detection of three major pathogens (microsporidians, nucleopolyhedrovirus (NPV) and densovirus (DNV)) infecting the silkworm, Bombyx mori. Multiplex PCR, using three primer pairs, two of which were designed from the conserved regions of 16S small subunit ribosomal RNA gene of microsporidians, and polyhedrin gene of NPVs respectively, and a third primer pair designed from the internal sequences of B. mori DNVs (BmDNV), showed discrete and pathogen specific PCR products. The assay showed high specificity and sensitivity for the pathogenic DNA. Under optimized PCR conditions, the assay yielded a 794 bp DNA fragment from Nosema bombycis, 471 bp fragment from B. mori NPV (BmNPV) and 391 bp fragment from BmDNV. Further, this detection method was successfully applied to other silkworm species such as Antheraea mylitta and Samia cynthia ricini, in detecting same or similar pathogens infecting them. This method is a valuable supplement to the conventional microscopic diagnostic methods and can be used for the early detection of pathogens infecting silkworms. Furthermore it can assist research and extension centers for the safe supply of disease-free silkworms to farmers. 相似文献
109.
Genetic association, post-translational modification, and protein-protein interactions in Type 2 diabetes mellitus 总被引:1,自引:0,他引:1
Sharma A Chavali S Mahajan A Tabassum R Banerjee V Tandon N Bharadwaj D 《Molecular & cellular proteomics : MCP》2005,4(8):1029-1037
Type 2 diabetes mellitus is a complex disorder with a strong genetic component. Inherited complex disease susceptibility in humans is most commonly associated with single nucleotide polymorphisms. The mechanisms by which this occurs are still poorly understood. Here we focus on analyzing the effect of a set of disease-causing missense variations of the monogenetic form of Type 2 diabetes mellitus and a set of disease-associated nonsynonymous variations in comparison with that of nonsynonymous variations without any experimental evidence for association with any disease. Analysis of different properties such as evolutionary conservation status, solvent accessibility, secondary structure, etc. suggests that disease-causing variations are associated with extreme changes in the value of the parameters relating to evolutionary conservation and/or protein stability. Disease-associated variations are rather moderately conserved and have a milder effect on protein function and stability. The majority of the genes harboring these variations are clustered in or near the insulin signaling network. Most of these variations are identified as potential sites for post-translational modifications; certain predictions have already reported experimental evidence. Overall our results indicate that Type 2 diabetes mellitus may result from a large number of single nucleotide polymorphisms that impair modular domain function and post-translational modifications involved in signaling. Our emphasis is more on conserved corresponding residues than the variation alone. We believe that the approach of considering a stretch of peptide sequence involving a polymorphism would be a better method of defining the role of the polymorphism in the manifestation of this disease. Because most of the variations associated with the disease are rare, we hypothesize that this disease is a "mosaic model" of interaction between a large number of rare alleles and a small number of common alleles along with the environment, which is little contrary to the existing common disease common variant model. 相似文献
110.
Narayana B Ashalatha BV Vijaya Raj KK Fernandes J Sarojini BK 《Bioorganic & medicinal chemistry》2005,13(15):4638-4644
An efficient and modified synthesis of ethyl-4-nitro/5-nitro/6-nitro and 7-nitroindole-2-carboxylates is described. Carbohydrazides of corresponding ethyl nitroindole-2-carboxylates underwent smooth one-step transformation to 1,3,4-oxadiazolyl nitroindoles (4a-l) on reaction with aromatic carboxylic acids in the presence of phosphorus oxychloride. An alternate method to synthesize 1,3,4-oxadiazolyl nitroindoles is also described. Among the newly synthesized 1,3,4-oxadiazolyl nitroindoles, a few compounds are studied for anti-inflammatory activity. 相似文献