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81.
Krishnamurthy Nakuluri Dhanunjay Mukhi Sathish Kumar Mungamuri Anil Kumar Pasupulati 《Journal of cellular biochemistry》2019,120(5):7667-7678
Glomerular podocytes are the major components of the renal filtration barrier, and altered podocyte permselectivity is a key event in the pathogenesis of proteinuric conditions. Clinical conditions such as ischemia and sleep apnea and extreme physiological conditions such as high-altitude sickness are presented with renal hypoxia and are associated with significant proteinuria. Hypoxia is considered as an etiological factor in the progression of acute renal injury. A sustained increase in hypoxia-inducible factor 1α (HIF1α) is a major adaptive stimulus to the hypoxic conditions. Although the temporal association between hypoxia and proteinuria is known, the mechanism by which hypoxia elicits proteinuria remains to be investigated. Furthermore, stabilization of HIF1α is being considered as a therapeutic option to treat anemia in patients with chronic kidney disease. Therefore, in this study, we induced stabilization of HIF1α in glomerular regions in vivo and in podocytes in vitro upon exposure to cobalt chloride. The elevated HIF1α expression is concurrence with diminished expression of nephrin and podocin, podocyte foot-processes effacement, and significant proteinuria. Podocytes exposed to cobalt chloride lost their arborized morphology and cell-cell connections and also displayed cytoskeletal derangements. Elevation in expression of HIF1α is in concomitance with loss of nephrin and podocin in patients with diabetic nephropathy and chronic kidney disease. In summary, the current study suggests that HIF1α stabilization impairs podocyte function vis-à-vis glomerular permselectivity. 相似文献
82.
In vivo administration of HSPI (10.7 kDa FSH suppressing peptide of prostate) to intact adult male rats was found to suppress the basal levels of incorporation of 3H-thymidine into DNA of ventral and dorsolateral lobes of the prostate, in a dose-dependent manner. Interestingly, microscopic examination of the prostate histology of HSPI treated rats revealed a significantly increased incidence of apoptotic bodies which are indicative of cell death. In another experiment, HSPI was also found to suppress the active DNA synthesis in testosterone-induced regrowth of prostate in castrated rats. Thus HSPI can suppress the basal and stimulated DNA synthesis and also induce apoptotic cell death in rat prostate. 相似文献
83.
The effect of addition of indole acetic acid (3 M) andNaCl (75 mM) on growth and enzymes of carbohydrate metabolism inchickpea seedlings was compared. In comparison with control seedlings, theseedlings growing in the presence of indole acetic acid (IAA) had reducedamylase activity in cotyledons and enhanced sucrose synthase (SS) and sucrosephosphate synthase (SPS) activities in cotyledons and shoots at all days ofseedling growth. Compared with control seedlings, sucrose content was higher incotyledons, shoots and roots and reducing sugar content was lower in shoots ofIAA treated seedlings. A low invertase (acid and alkaline) activity in shoots ofIAA treated seedlings could lead to reduced sink strength and hence decreasedgrowth of seedlings. Effects of NaCl stress on growth and activities of amylase,SS and SPS in cotyledons and invertase, SS and SPS in shoots were similar tothose observed with addition of IAA. 相似文献
84.
A single candidate 4'-phosphopantetheine transferase, identified by BLAST searches of the human genome sequence data base, has been cloned, expressed, and characterized. The human enzyme, which is expressed mainly in the cytosolic compartment in a wide range of tissues, is a 329-residue, monomeric protein. The enzyme is capable of transferring the 4'-phosphopantetheine moiety of coenzyme A to a conserved serine residue in both the acyl carrier protein domain of the human cytosolic multifunctional fatty acid synthase and the acyl carrier protein associated independently with human mitochondria. The human 4'-phosphopantetheine transferase is also capable of phosphopantetheinylation of peptidyl carrier and acyl carrier proteins from prokaryotes. The same human protein also has recently been implicated in phosphopantetheinylation of the alpha-aminoadipate semialdehyde dehydrogenase involved in lysine catabolism (Praphanphoj, V., Sacksteder, K. A., Gould, S. J., Thomas, G. H., and Geraghty, M. T. (2001) Mol. Genet. Metab. 72, 336-342). Thus, in contrast to yeast, which utilizes separate 4'-phosphopantetheine transferases to service each of three different carrier protein substrates, humans appear to utilize a single, broad specificity enzyme for all posttranslational 4'-phosphopantetheinylation reactions. 相似文献
85.
Saxena AK Ram S Saxena M Singh N Prathipati P Jain PC Singh HK Anand N 《Bioorganic & medicinal chemistry》2003,11(9):2085-2090
A series of nineteen substituted 1,2,3,4,6,7,12,12a-octahydropyrazino[2',1':6,1]pyrido[3, 4-b]indoles analogues of neuroleptic drug, Centbutindole have been studied using quantitative structure-activity relationship analysis. The derived models display good fits to the experimental data (r>or=0.75) having good predictive power (r(cv)>or=0.688). The best model describes a high correlation between predicted and experimental activity data (r=0.967). Statistical analysis of the equation populations indicates that hydrophobicity (as measured by pi(R), logP(o/w) and SlogP_VSA8), dipole y and structural parameters in terms of indicator variable, (In(1)) and globularity are important variables in describing the variation in the neuroleptic activity in the series. 相似文献
86.
Rajkumari Sanjukta Mohammad Samir Farooqi Naveen Sharma Anil Rai Dwijesh Chandra Mishra Dhananjaya P Singh 《Bioinformation》2012,8(22):1087-1095
Chromohalobacter salexigens, a Gammaproteobacterium belonging to the family Halomonadaceae, shows a broad salinity range for
growth. In order to reveal the factors influencing architecture of protein coding genes in C. salexigens, pattern of synonymous codon
usage bias has been investigated. Overall codon usage analysis of the microorganism revealed that C and G ending codons are
predominantly used in all the genes which are indicative of mutational bias. Multivariate statistical analysis showed that the genes
are separated along the first major explanatory axis according to their expression levels and their genomic GC content at the
synonymous third positions of the codons. Both NC plot and correspondence analysis on Relative Synonymous Codon Usage
(RSCU) indicates that the variation in codon usage among the genes may be due to mutational bias at the DNA level and natural
selection acting at the level of mRNA translation. Gene length and the hydrophobicity of the encoded protein also influence the
codon usage variation of genes to some extent. A comparison of the relative synonymous codon usage between 10% each of highly
and lowly expressed genes determines 23 optimal codons, which are statistically over represented in the former group of genes and
may provide useful information for salt-stressed gene prediction and gene-transformation. Furthermore, genes for regulatory
functions; mobile and extrachromosomal element functions; and cell envelope are observed to be highly expressed. The study
could provide insight into the gene expression response of halophilic bacteria and facilitate establishment of effective strategies to
develop salt-tolerant crops of agronomic value. 相似文献
87.
Toxic effect of metal cations on female reproduction and gonadal functions was studied. Adult synchronized female rats were treated intraperitoneally with lead acetate and cadmium acetate separately and in combination (0.025, 0.05 and 0.1 mg/kg body wt) for 15 days. The metabolizing enzymes (17beta-hydroxy steroid oxidoreductase and UDP glucoronyl transferase) activities decreased with increasing dose showing significant change compared to control. Also, significant decrease in cytochrome P450 (CYP450) content was found after the treatment. Displacement of zinc bound to metallothionein was more in cadmium treated rats compared to other groups. In all these parameters, treatment in combination of lead and cadmium showed intermediate results indicating some kind of competition between the two metals. But the histological studies showed that combined treatment caused more cytotoxic effect than cadmium and lead alone. These results indicated that metal cations tested did have a direct inhibitory effect on metabolizing enzyme activities. 相似文献
88.
89.
Raman and polarized ir spectra have been obtained on built-up monomolecular films of poly(α-aminoisobutyric acid), and analyzed in the context of normal mode calculations on 310-, α-, and α′-helix conformations of this molecule. The average discrepancy between observed and calculated frequencies is significantly smaller for the 310-helix than for the other structures. This, together with the more satisfactory explanation of several special features of the spectra, indicates that this polypeptide adopts a 310-helix conformation in such thin films. 相似文献
90.
Mycelium of Fusarium oxysporum grown on a glucose-containing medium lacked fructosyl transferase and invertase activities. Synthesis of fructosyl t 相似文献