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71.
Keshab Deuba Anna Mia Ekstr?m Rachana Shrestha George Ionita Laxmi Bhatta Deepak Kumar Karki 《PloS one》2013,8(3)
Background
Men who have sex with men (MSM) are marginalized, hidden, underserved and at high risk for HIV in Nepal. We examined the association between MSM sub-populations, psychosocial health problems and support, access to prevention and non-use of condoms.Methods
Between September-November of 2010, a cross-sectional survey on HIV-related risk behavior was performed across Nepal through snowball sampling facilitated by non-governmental organizations, recruiting 339 MSM, age 15 or older. The primary outcomes were: (a) non-use of condoms at least once in last three anal sex encounters with men and (b) non-use of condoms with women in the last encounter. The secondary outcome was participation in HIV prevention interventions in the past year.Results
Among the 339 MSM interviewed, 78% did not use condoms at their last anal sex with another man, 35% did not use condoms in their last sex with a woman, 70% had experienced violence in the last 12 months, 61% were experiencing depression and 47% had thought of committing suicide. After adjustment for age, religion, marital status, and MSM subpopulations (bisexual, ta, meti, gay), non-use of condoms at last anal sex with a man was significantly associated with non-participation in HIV interventions, experience of physical and sexual violence, depression, repeated suicidal thoughts, small social support network and being dissatisfied with social support. Depression was marginally associated with non-use of condoms with women. The findings suggest that among MSM who reported non-use of condoms at last anal sex, the ta subgroup and those lacking family acceptance were the least likely to have participated in any preventive interventions.Conclusions
MSM in Nepal have a prevalence of psychosocial health problems in turn associated with high risk behavior for HIV. Future HIV prevention efforts targeting MSM in Nepal should cover all MSM subpopulations and prioritize psychosocial health interventions. 相似文献72.
Trivedi Vijay Laxmi Attri Dharam Chand Sati Jyoti Nautiyal Mohan Chandra 《Journal of plant biochemistry and biotechnology.》2020,29(2):225-235
Journal of Plant Biochemistry and Biotechnology - Dioecious nature of a plant shows variations in male and female individuals of that species, due to their differential role in sexual reproduction.... 相似文献
73.
Vijaya Laxmi S Thirupathi Reddy Y Suresh Kuarm B Narsimha Reddy P Crooks PA Rajitha B 《Bioorganic & medicinal chemistry letters》2011,21(14):4329-4331
A novel series of barbiturate and thiobarbiturate analogs of 2-benzoyl-3-methyl-5-oxo-5H-furo[3,2-g]chromene-6-carbaldehydes (3a-g and 4a-d, respectively) and 6-methyl-4,8-dioxo-4,8-dihydropyrano[3,2-g]chromenes (7a-c), were synthesized and evaluated for their antitubercular activities against Mycobacterium tuberculosis H37RV, and cytotoxicity (CC50) in the VERO cell MABA assay. The results indicate that the furanochromene series of compounds (3a-g and 4a-d) showed only weak to moderate antitubercular activity. However, the pyranochromene analog 7b showed good antitubercular activity (IC90: 5.9 μg/mL) and cytotoxicity (CC50: 14.27 μg/mL). The antitubercular activity of 7b was superior to the antituberculosis drug, pyrazinamide (PZA; IC90: >20 μg/mL). Analog 7b was considered to be a lead compound for subsequent structural optimization. 相似文献
74.
Yasui M Suzuki N Liu X Okamoto Y Kim SY Laxmi YR Shibutani S 《Journal of molecular biology》2007,371(5):1151-1162
4-Hydroxyequilenin (4-OHEN)-dC is a major, potentially mutagenic DNA adduct induced by equine estrogens used for hormone replacement therapy. To study the miscoding property of 4-OHEN-dC and the involvement of Y-family human DNA polymerases (pols) eta, kappa and iota in that process, we incorporated 4-OHEN-dC into oligodeoxynucleotides and used them as templates in primer extension reactions catalyzed by pol eta, kappa and iota. Pol eta inserted dAMP opposite 4-OHEN-dC, accompanied by lesser amounts of dCMP and dTMP incorporation and base deletion. Pol kappa promoted base deletions as well as direct incorporation of dAMP and dCMP. Pol iota worked in conjunction with pol kappa, but not with pol eta, at a replication fork stalled by the adduct, resulting in increased dTMP incorporation. Our results provide a direct evidence that Y-family DNA pols can switch with one another during synthesis past the lesion. No direct incorporation of dGMP, the correct base, was observed with Y-family enzymes. The miscoding potency of 4-OHEN-dC may be associated with the development of reproductive cancers observed in women receiving hormone replacement therapy. 相似文献
75.
Duration of ERK1/2 phosphorylation induced by FGF or ocular media determines lens cell fate 总被引:4,自引:0,他引:4
Iyengar L Wang Q Rasko JE McAvoy JW Lovicu FJ 《Differentiation; research in biological diversity》2007,75(7):662-668
The ocular environment is important for the establishment and maintenance of lens growth patterns and polarity. In the anterior chamber of the eye, the aqueous humour regulates lens epithelial cell proliferation whereas in the posterior, the vitreous humour regulates the differentiation of the lens cells into fiber cells. Members of the fibroblast growth factor (FGF) growth factor family have been shown to induce lens epithelial cells to undergo cell division and differentiate into fibers, with a low dose of FGF able to induce cell proliferation (but not fiber differentiation), and higher doses required to induce fiber differentiation. Both these cellular events have been shown to be regulated by the MAPK/ERK1/2 signalling pathway. In the present study, to better understand the contribution of ERK1/2 signalling in regulating lens cell proliferation and differentiation, we characterized the ERK1/2 signalling profiles induced by different doses of FGF, and compared these to those induced by the different ocular media. Here, we show that FGF induced a dose-dependent sustained activation of ERK1/2, with both a high (fiber differentiating) dose of FGF and vitreous, stimulating and maintaining a prolonged (up to 18 hr) ERK1/2 phosphorylation profile. In contrast, a lower (proliferating) dose of FGF, and aqueous, stimulated ERK1/2 phosphorylation for only up to 6 hr. If we selectively reduce the 18 hr ERK1/2 phosphorylation profile induced by vitreous to 6 hr, by specifically blocking FGF receptor signalling, the vitreous now fails to induce lens fiber differentiation but retains the ability to induce lens cell proliferation. These findings not only provide insights into the important role that FGF plays in the different ocular media that bathe the lens, but enlighten us on some of the putative molecular mechanisms by which one specific growth factor, in this case FGF, can elicit a different cellular response in the same cell type. 相似文献
76.
Pape HC Driesang RB Heinbockel T Laxmi TR Meis S Seidenbecher T Szinyei C Frey U Stork O 《Zoology (Jena, Germany)》2001,104(3-4):232-240
The amygdala is considered a core structure of the so-called limbic system and has been implicated in a variety of functions, including emotional interpretation of sensory information, emotional arousal, emotional memory, fear and anxiety, and related clinical disorders. Despite the clinical and functional importance of the amygdala, it is only recently that some general principles of intra-amygdaloid mechanisms of signal processing that are relevant for fear behavior and memory have emerged from behavioral, anatomical, electrophysiological, and neurochemical studies performed in the amygdala of various mammalian species in vivo, in situ and in vitro. 相似文献
77.
Gautam Anand Annapurna Bhattacharjee Vijay Laxmi Shrivas Shubham Dubey Shilpi Sharma 《Physiology and Molecular Biology of Plants》2021,27(7):1547
Salinity is a major abiotic stress that negatively impacts plant health and soil microbiota. ACC (1-aminocyclopropane carboxylic acid) deaminase producing microorganisms act as natural stress busters that protect plants from different kinds of stresses. The study focused on the isolation of potent, indigenous, multi-trait ACC deaminase producers. The shortlisted ACC deaminase producers were checked for their ability to promote growth of Cajanus cajan, and mitigate stress under laboratory conditions followed by validation of their potency in naturally saline field conditions. Physiological stress markers were assessed to evaluate the impact of salinity in plants treated with ACC deaminase producer, compared to controls. Further, the contribution of ACC deaminase in stress mitigation was demonstrated by using a chemical inhibitor for ethylene biosynthesis. This study presents a polyphasic approach, transitioning from the rhizospheric soil to the laboratory to validation in the field, and puts forth a promising eco-friendly alternative for sustainable agriculture.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12298-021-01031-0. 相似文献
78.
GaneshPrasad ArunKumar David F. Soria-Hernanz Valampuri John Kavitha Varatharajan Santhakumari Arun Adhikarla Syama Kumaran Samy Ashokan Kavandanpatti Thangaraj Gandhirajan Koothapuli Vijayakumar Muthuswamy Narayanan Mariakuttikan Jayalakshmi Janet S. Ziegle Ajay K. Royyuru Laxmi Parida R. Spencer Wells Colin Renfrew Theodore G. Schurr Chris Tyler Smith Daniel E. Platt Ramasamy Pitchappan The Genographic Consortium 《PloS one》2012,7(11)
Previous studies that pooled Indian populations from a wide variety of geographical locations, have obtained contradictory conclusions about the processes of the establishment of the Varna caste system and its genetic impact on the origins and demographic histories of Indian populations. To further investigate these questions we took advantage that both Y chromosome and caste designation are paternally inherited, and genotyped 1,680 Y chromosomes representing 12 tribal and 19 non-tribal (caste) endogamous populations from the predominantly Dravidian-speaking Tamil Nadu state in the southernmost part of India. Tribes and castes were both characterized by an overwhelming proportion of putatively Indian autochthonous Y-chromosomal haplogroups (H-M69, F-M89, R1a1-M17, L1-M27, R2-M124, and C5-M356; 81% combined) with a shared genetic heritage dating back to the late Pleistocene (10–30 Kya), suggesting that more recent Holocene migrations from western Eurasia contributed <20% of the male lineages. We found strong evidence for genetic structure, associated primarily with the current mode of subsistence. Coalescence analysis suggested that the social stratification was established 4–6 Kya and there was little admixture during the last 3 Kya, implying a minimal genetic impact of the Varna (caste) system from the historically-documented Brahmin migrations into the area. In contrast, the overall Y-chromosomal patterns, the time depth of population diversifications and the period of differentiation were best explained by the emergence of agricultural technology in South Asia. These results highlight the utility of detailed local genetic studies within India, without prior assumptions about the importance of Varna rank status for population grouping, to obtain new insights into the relative influences of past demographic events for the population structure of the whole of modern India. 相似文献
79.
Savita Kerkar Laxmi Raiker Anil Tiwari Shanmugam Mayilraj Syed Dastager 《Biologia》2012,67(3):454-460
Biofilm mats appear in salterns distinctively during the monsoon season when the salinity decreases below 12 percentile salinity units and within a short period cover the entire surface area of the saltern. A study was carried out in two salterns viz. Nerul and Curca to find a possible reason for the rapid proliferation of these solar biofilms. Out of the 125 bacteria isolated from these biofilms, 16 produced indole-3-acetic acid (IAA). Rapid in-situ assay with Salkowski reagent and HPLC analysis confirmed the IAA production. Four isolates consistently produced high IAA concentrations ranging from 9.5 to 14.2 μg/mL in the presence of 4 mg/mL tryptophan concentrations in the growth media. The IAA-producing bacteria were Aeromonas aquariorum (N2), Pseudomonas alcaliphila (N3), Vibrio diazotrophicus (N6) and Pseudomonas pachastrellae (C3). These four IAA-producing bacteria also produced other growth promoting factors like ammonia. Three isolates produced siderophores and were phosphate solubilizers. There was enhancement in the growth of Cicer arietinum (length of the shoot and root) under axenic conditions and of biofilm mats (r = 0.9, p < 0.001; r = 0.8, p < 0.05 and r = 0.946, p < 0.01, respectively). This is, according to our knowledge, the first report indicating IAA-producing bacteria isolated from biofilms enhancing the proliferation of these biofilm mats in the solar salterns. 相似文献
80.
Treatment with estrogen increases the risk of breast, ovary, and endometrial cancers in women. DNA damage induced by estrogen is thought to be involved in estrogen carcinogenesis. In fact, Y-family human DNA polymerases (pol) eta and kappa, which are highly expressed in the reproductive organs, miscode model estrogen-derived DNA adducts during DNA synthesis. Since the estrogen-DNA adducts are a mixture of 6alpha- and 6beta-diastereoisomers of dG-N(2)-6-estrogen or dA-N(6)-6-estrogen, the stereochemistry of each isomeric adduct on translesion synthesis catalyzed by DNA pols has not been investigated. We have recently established a phosphoramidite chemical procedure to insert 6alpha- or 6beta-isomeric N(2)-(estradiol-6-yl)-2'-deoxyguanosine (dG-N(2)-6-E(2)) into oligodeoxynucleotides. Using such site-specific modified oligomer as a template, the specificity and frequency of miscoding by dG-N(2)-6alpha-E(2) or dG-N(2)-6beta-E(2) were explored using pol eta and a truncated form of pol kappa (pol kappaDeltaC). Translesion synthesis catalyzed by pol eta bypassed both the 6alpha- and 6beta-isomers of dG-N(2)-6-E(2), with a weak blockage at the adduct site, while translesion synthesis catalyzed by pol kappaDeltaC readily bypassed both isomeric adducts. Quantitative analysis of base substitutions and deletions occurring at the adduct site showed that pol kappaDeltaC was more efficient than pol eta by incorporating dCMP opposite both 6alpha- and 6beta-isomeric dG-N(2)-6-E(2) adducts. The miscoding events occurred more frequently with pol eta, but not with pol kappaDeltaC. Pol eta promoted incorporation of dAMP and dTMP at both the 6alpha- and 6beta-isomeric adducts, generating G --> T transversions and G --> A transitions. One- and two-base deletions were also formed. The 6alpha-isomeric adduct promoted slightly lower frequency of dCMP incorporation and higher frequency of dTMP incorporation and one-base deletions, compared with the 6beta-isomeric adduct. These observations were supported by steady-state kinetic studies. Taken together, the miscoding property of the 6alpha-isomeric dG-N(2)-6-E(2) is likely to be similar to that of the 6beta-isomeric adduct. 相似文献