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991.
Glutamine is a major nutrient utilized by the intestinal epithelium and is primarily assimilated via Na-glutamine co-transport (NGcT) on the brush border membrane (BBM) of enterocytes. Recently we reported that B(0)AT1 (SLC6A19) mediates glutamine absorption in villus while SN2 (SLC38A5) does the same in crypt cells. However, how B(0)AT1 and SN2 are affected during intestinal inflammation is unknown. In the present study it was shown that during chronic enteritis NGcT was inhibited in villus cells, however, it was stimulated in crypt cells. Our studies also demonstrated that the mechanism of inhibition of NGcT during chronic enteritis was secondary to a reduction in the number of B(0)AT1 co-transporters in the villus cell BBM without a change in the affinity of the co-transporter. In contrast, stimulation of NGcT in crypt cells was secondary to an increase in the affinity of SN2 for glutamine without an alteration in the number of co-transporters. Thus, glutamine assimilation which occurs via distinct transporters in crypt and villus cells is altered in the chronically inflamed intestine. 相似文献
992.
993.
Ilka Nemere Natalio Garbi Gunter J. H?mmerling Ramesh C. Khanal 《The Journal of biological chemistry》2010,285(41):31859-31866
We have crossed ERp57flx/flx mice with commercially available mice expressing villin-driven cre-recombinase. Lysates of intestinal epithelial cells were prepared from knock-out (KO) mice and littermates (LM) and used in Western blot analyses with Ab099 against the N terminus of the 1,25D3-MARRS (membrane-associated, rapid response steroid-binding) receptor: LM mice exhibited one positive band, which was absent in preparations from KO mice. Saturation analyses of cell lysates with [3H]1,25D3 revealed negligible binding in preparations from either female or male KOs. Lysates from female and male LM mice had similar affinities but different numbers of binding sites. Isolated enterocytes were tested for steroid-stimulated calcium uptake. Treatment of cells from female or male LM mice with 1,25D3 elicited enhanced calcium uptake in females and males within 5 min. Intestinal cells from KO mice exhibited a severely blunted or completely absent response to hormone. Confocal microscopy of intestinal cells revealed the presence of cell surface vitamin D receptors. However, antibodies to the vitamin D receptor failed to block 1,25D3-stimulated calcium uptake. In chick enterocytes we have found that the PKA pathway mediates calcium uptake. The time course for activation of PKA in mouse enterocytes paralleled that for enhanced calcium uptake and for LM females reached 250% of controls within 5 min, and 150% of controls in cells prepared from LM males. Enterocytes from female or male KO mice failed to exhibit steroid hormone-stimulated PKA activity, but did respond to forskolin with enhanced calcium uptake. We conclude that the 1,25D3-MARRS receptor is of central importance to steroid hormone-stimulated calcium uptake in mammalian intestinal cells. 相似文献
994.
995.
Javad Tavakkoly-Bazzaz Mahsa M. Amoli Vera Pravica Ramesh Chandrasecaran Andrew J. M. Boulton Bagher Larijani Ian V. Hutchinson 《Molecular biology reports》2010,37(7):3625-3630
Vascular factors beside metabolic problems are involved in both etiopathogenesis of diabetic neuropathy, and more remarkably,
later in “repair” phase, that governs the net balance between neuro-regenerative/degenerative reactions. Regarding ischemic
nature of diabetic neuropathy that highlights necessity of blood vessels re-establishment during tissue healing, VEGF (vascular
endothelial growth factor) has been recently the subject of extensive investigations in diabetic neuropathy (DNU). This growth
factor possesses angiogenic potentials in addition to the hemodynamic functions. The distribution of VEGF gene polymorphisms
at positions −7*C/T, −1001*G/C, −1154*G/A and −2578*C/A were analysed by ARMS–PCR in 248 type 1 diabetic British-Caucasian
subjects (81 DNU+, 167 DNU−). We have found that distribution of a VEGF gene polymorphism at promoter region (−7*C/T) was
significantly different between diabetic subjects with vs. without neuropathy and the allele (C) conferred susceptibility
to DNU (P = 0.02; OR = 1.78, 95% CI 1.0–3.1). The present study indicates that polymorphism of the VEGF gene at position −7*C/T might
be implicated in the pathogenesis of diabetic neuropathy as it may harbour some functional/regulatory potential in VEGF gene
expression. However, this requires further studies in order to better understand its phenotypic impact and to investigate
the prognostic value of this polymorphism in diabetic neuropathy as a chronic complication of diabetes. 相似文献
996.
Jitendra Nath Tiwari Mudiam Mohana Krishna Reddy Devendra Kumar Patel Sudhir Kumar Jain Ramesh Chandra Murthy Natesan Manickam 《World journal of microbiology & biotechnology》2010,26(10):1727-1733
Polycyclic aromatic hydrocarbons (PAHs) are common ubiquitous pollutants existing in nature with high recalcitrance and toxicity.
In this study a bacterium capable of aerobic degradation of high molecular weight PAHs (with special reference to pyrene)
was isolated by selective enrichment culture technique from oil refinery effluent sludge. The isolate was characterized as
Achromobacter xylooxidans by 16S rRNA gene sequence analysis technique. For the first time it is hereby reported a bacterium capable of effectively
degrading pyrene (up to 80%), as evident by reverse phase high performance liquid chromatographic analysis (RP-HPLC). After
incubation of Achromobacter xylooxidans in minimal salt medium (MSM) containing pyrene, at concentration of 200 mg/L, as sole source of carbon and energy, there
was decrease in pyrene concentration concomitant with increase in bacterial cell protein concentration. RP-HPLC analysis revealed
that pyrene was degraded into three metabolites viz. I, II and III. The RP-HPLC eluent fraction were collected from 2.5 to
32.0 min by repeated injection of degraded sample, concentrated and analyzed on gas chromatography mass spectroscopy (GC-MS)
for metabolite identification. The fraction shows 1-hydroxypyrene, 1-hydroxy-6-methoxypyrene and 1,6dimethoxypyrene as metabolic
product of pyrene degradation, on the basis of their m/z values. On contrary to the reported PAH degradation with reference to pyrene by different isolates till date; the efficient
degradation, as evident by RP-HPLC, by this isolate holds a promising potential for planning of bioremediation strategies
of contaminated sites. 相似文献
997.
Association of melanin content with conidiogenesis in Bipolaris Sorokiniana of barley (Hordeum vulgare L.) 总被引:1,自引:0,他引:1
B. M. Bashyal Ramesh Chand Chanda Kushwaha Devyani Sen L. C. Prasad A. K. Joshi 《World journal of microbiology & biotechnology》2010,26(2):309-316
Sixty-seven isolates of Bipolaris sorokiniana of barley, belonging to three groups (black, white and mixed) were studied to find an association of melanin with the spore production of the fungus. Conidiogenesis in black, white and mixed subpopulation of B. sorokiniana was positively correlated with melanin content/g of mycelium. Primary hyphae of black and mixed subpopulation differentiated into secondary hyphal structures which subsequently produced conidiophores and conidia. Primary hyphae could not differentiate into secondary hyphae and subsequently conidiophores and conidia in white subpopulation. A melanin containing mutant developed from white subpopulation regained its ability to differentiate into secondary hyphae, conidiophores and conidia. Results showed that melanization of mycelia B. sorokiniana mycelia is an important factor for conidia production. 相似文献
998.
William J. Moore Jeffrey C. Kern Ramesh Bhat Peter V.N. Bodine Shoichi Fukyama Girija Krishnamurthy Ronald L. Magolda Keith Pitts Barb Stauffer Eugene J. Trybulski 《Bioorganic & medicinal chemistry》2010,18(1):190-201
Piperidinyl diphenylsulfonyl sulfonamides are a novel class of molecules that have inhibitory binding affinity for sFRP-1. As a secreted protein sFRP-1 inhibits the function of the secreted Wnt glycoprotein. Therefore, as inhibitors of sFRP-1 these small molecules facilitate the Wnt/β-catenin canonical signaling pathway. Details of the structure–activity relationships and biological activity of this structural class of compounds will be discussed. 相似文献
999.
1000.
Gopi M. Joyson Joe Jeevamani J. Goutham S. Simon Nina Tabitha Deepak Samuel V. Abhilash K. R. Robin R. S. Hariharan G. Muruganandam R. Krishnan P. Purvaja R. Ramesh R. 《Wetlands Ecology and Management》2021,29(5):653-668
Wetlands Ecology and Management - Coral reefs of Lakshadweep perform a range of vital ecosystem functions and sustain the livelihoods of island communities. Coral reefs provide ecosystem services... 相似文献