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51.
The problem of estimation of variance components based on diallel model for unbalanced data has been addressed. The least squares approach to quadratic estimation has been adopted in obtaining the explicit solutions for the design and genetic components of variance. 相似文献
52.
Resistance to fluconazole in Candida albicans from AIDS patients correlated with reduced intracellular accumulation of drug 总被引:1,自引:0,他引:1
K. Venkateswarlu D.W. Denning N.J. Manning S.L. Kelly 《FEMS microbiology letters》1995,131(3):337-341
Abstract Mucosal candidosis is an almost inevitable consequence of AIDS. Resistance to fluconazole therapy associated with enhanced tolerance, detectable in microbiological estimation of sensitivity, occurs in up to 10% of cases with late-stage AIDS. We report here our biochemical analysis of the basis of resistance in a study of two susceptible and two resistant isolates. Resistance was not associated with a change in the target enzyme sterol 14α-demethylase, as indicated by equivalent levels of fluconazole inhibition of activity in extracts from all four isolates, or by mutations in sterol Δ 5,6 desaturase as previously observed in Saccharomyces cereuisiae and Ustilago maydis . Reduced cellular content of fluconazole in the resistant isolates of between six to ten-fold was observed which could account for their resistant phenotype. 相似文献
53.
Desmids of Andhra Pradesh,I from Pakhal Lake,Warangal 总被引:1,自引:1,他引:0
54.
The morphology of the pachytene chromosomes ofPennisetum purpureum was studied. On the basis of relative lengths and arm ratios it was possible to identify them individually. They are numbered
1 to 14 in the order of their decreasing lengths and diagnostic characters are given for each chromosome. The first and the
fourteenth chromosomes, the longest and the shortest of the complement respectively, are the nucleolus organizing chromosome.
In all the fourteen chromosomes the centromeres are flanked by deep staining regions. This feature is common to the two species.P. typhoides andP. purpureum. Seven out of the fourteen chromosomes have terminal knobs in their long arms. This is a feature in which it differs from
the other seven chromosome species.Pennisetum typhoides. These knobs, however, are not present uniformly in all populations; material obtained from Ghana did not show these knobs. 相似文献
55.
Mms2-Ubc13-dependent and -independent roles of Rad5 ubiquitin ligase in postreplication repair and translesion DNA synthesis in Saccharomyces cerevisiae
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Gangavarapu V Haracska L Unk I Johnson RE Prakash S Prakash L 《Molecular and cellular biology》2006,26(20):7783-7790
The Rad6-Rad18 ubiquitin-conjugating enzyme complex of Saccharomyces cerevisiae promotes replication through DNA lesions via three separate pathways that include translesion synthesis (TLS) by DNA polymerases eta and zeta and postreplicational repair (PRR) of discontinuities that form in the newly synthesized DNA opposite from DNA lesions, mediated by the Mms2-Ubc13 ubiquitin-conjugating enzyme and Rad5. Rad5 is an SWI/SNF family ATPase, and additionally, it functions as a ubiquitin ligase in the ubiquitin conjugation reaction. To decipher the roles of these Rad5 activities in lesion bypass, here we examine the effects of mutations in the Rad5 ATPase and ubiquitin ligase domains on the PRR of UV-damaged DNA and on UV-induced mutagenesis. Even though the ATPase-defective mutation confers only a modest degree of UV sensitivity whereas the ubiquitin ligase mutation causes a high degree of UV sensitivity, we find that both of these mutations produce the same high level of PRR defect as that conferred by the highly UV-sensitive rad5Delta mutation. From these studies, we infer a requirement of the Rad5 ATPase and ubiquitin ligase activities in PRR, and based upon the effects of different rad5 mutations on UV mutagenesis, we suggest a role for Rad5 in affecting the efficiency of lesion bypass by the TLS polymerases. In contrast to the role of Rad5 in PRR, however, where its function is coupled with that of Mms2-Ubc13, Rad5 function in TLS would be largely independent of this ubiquitin-conjugating enzyme complex. 相似文献
56.
Hao Zhang Denis E. Ryono Pratik Devasthale Wei Wang Kevin O’Malley Dennis Farrelly Liqun Gu Thomas Harrity Michael Cap Cuixia Chu Kenneth Locke Litao Zhang Jonathan Lippy Lori Kunselman Nathan Morgan Neil Flynn Lisa Moore Vinayak Hosagrahara Lisa Zhang Pathanjali Kadiyala Peter T.W. Cheng 《Bioorganic & medicinal chemistry letters》2009,19(5):1451-1456
The design, synthesis and structure–activity relationships of a novel series of N-phenyl-substituted pyrrole, 1,2-pyrazole and 1,2,3-triazole acid analogs as PPAR ligands are outlined. The triazole acid analogs 3f and 4f were identified as potent dual PPARα/γ agonists both in binding and functional assays in vitro. The 3-oxybenzyl triazole acetic acid analog 3f showed excellent glucose and triglyceride lowering in diabetic db/db mice. 相似文献
57.
58.
Jessica M. Bon Joseph K. Leader Joel L. Weissfeld Harvey O. Coxson Bin Zheng Robert A. Branch Venkateswarlu Kondragunta Janet S. Lee Yingze Zhang Augustine M. K. Choi Anna E. Lokshin Naftali Kaminski David Gur Frank C. Sciurba 《PloS one》2009,4(8)
Background
Chronic obstructive pulmonary disease (COPD) is characterized by both airway remodeling and parenchymal destruction. The identification of unique biomarker patterns associated with airway dominant versus parenchymal dominant patterns would support the existence of unique phenotypes representing independent biologic processes. A cross-sectional study was performed to examine the association of serum biomarkers with radiographic airway and parenchymal phenotypes of COPD.Methodology/Principal Findings
Serum from 234 subjects enrolled in a CT screening cohort was analyzed for 33 cytokines and growth factors using a multiplex protein array. The association of serum markers with forced expiratory volume in one second percent predicted (FEV1%) and quantitative CT measurements of airway thickening and emphysema was assessed with and without stratification for current smoking status. Significant associations were found with several serum inflammatory proteins and measurements of FEV1%, airway thickening, and parenchymal emphysema independent of smoking status. The association of select analytes with airway thickening and emphysema was independent of FEV1%. Furthermore, the relationship between other inflammatory markers and measurements of physiologic obstruction or airway thickening was dependent on current smoking status.Conclusions/Significance
Airway and parenchymal phenotypes of COPD are associated with unique systemic serum biomarker profiles. Serum biomarker patterns may provide a more precise classification of the COPD syndrome, provide insights into disease pathogenesis and identify targets for novel patient-specific biological therapies. 相似文献59.
S. K. Arepalli V. Sridhar J. Venkateswara Rao P. Kavin Kennady Y. Venkateswarlu 《Apoptosis : an international journal on programmed cell death》2009,14(5):729-740
Bioassay directed fractionation and purification led to the successful isolation of a furano sesquiterpene, Methyl 5-[(1E,5E)-2,6-Dimethyl
octa-1,5,7-trienyl] furan-3-carboxylate (MDTFC), a bioactive component from a soft coral, Sinularia kavarittiensis. Its structure was determined by analyzing 1H, 13C NMR and FAB-MS. The results show that MDTFC could efficiently and selectively inhibit the proliferation of several human
cancer cell lines. Among all the cell lines, THP-1 was found to be most sensitive (IC50 29.59 μM), whereas the peripheral blood mononuclear cells were least effected (IC50 464.16 μM). The molecular mechanism of MDTFC mediated apoptosis was investigated for the first time. Induction of apoptosis
in THP-1 cells was characterized by cell membrane blebbing, chromatin condensation, DNA fragmentation, and decrease in level
of pro-caspases 3, 9 and increase in Bax/Bcl-2 ratio. Our results were further strengthened through cleavage of poly (ADP-ribose)
polymerase, reduction of mitochondrial membrane potential (Ψm) and cytosolic release of cytochrome c, which are key events during apoptosis. Moreover, phosphatidyl serine exposure and appearance of sub-G1 peak also demonstrated
cell death, when analyzed by flow cytometry. DNA fragmentation was prevented moderately when pretreated with caspase-9 inhibitor
(Z-LEHD-FMK) and largely with caspase-3 inhibitor (Z-DEVD-FMK). In summary, MDTFC mediated apoptosis involves mitochondria-dependent
pathway and the present compound of marine origin might have a therapeutic value against human cancer cell lines and especially
on leukemia cells. 相似文献
60.
V. Sandhya Sk. Z. Ali B. Venkateswarlu Gopal Reddy Minakshi Grover 《Archives of microbiology》2010,192(10):867-876
In this study we isolated and screened drought tolerant Pseudomonas isolates from arid and semi arid crop production systems of India. Five isolates could tolerate osmotic stress up to −0.73 MPa
and possessed multiple PGP properties such as P-solubilization, production of phytohormones (IAA, GA and cytokinin), siderophores,
ammonia and HCN however under osmotic stress expression of PGP traits was low compared to non-stressed conditions. The strains
were identified as Pseudomonas
entomophila, Pseudomonas
stutzeri, Pseudomonas putida, Pseudomonas syringae and Pseudomonas monteilli respectively on the basis of 16S rRNA gene sequence analysis. Osmotic stress affected growth pattern of all the isolates
as indicated by increased mean generation time. An increase level of intracellular free amino acids, proline, total soluble
sugars and exopolysaccharides was observed under osmotic stress suggesting bacterial response to applied stress. Further,
strains GAP-P45 and GRFHYTP52 showing higher levels of EPS and osmolytes (amino acids and proline) accumulation under stress
as compared to non-stress conditions, also exhibited higher expression of PGP traits under stress indicating a relationship
between stress response and expression of PGP traits. We conclude that isolation and screening of indigenous, stress adaptable
strains possessing PGP traits can be a method for selection of efficient stress tolerant PGPR strains. 相似文献