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91.
Kumar V Prakash O Manpreet S Sumedh G Medhi B 《Indian journal of experimental biology》2006,44(9):683-692
HIV infection is the serious medical and public health issue of present generation. By 2005, it has already infected a cumulative total of more than sixty million people worldwide and the number of HIV positive cases are rising day by day. India is currently estimated to have about 5.1 million infected persons with HIV-1 or AIDS (second only to South Africa) and this number could increase to 24 million in the next ten years. This pandemic situation of the AIDS stimulated a plethora of longitudinal cohort studies which are designed to document medical heterogeneity as well as to mitigate the factors that regulate the HIV-1 infection, disease progression and the immune defenses. In recent years these genetic studies have led to the discovery of various MHC and non MHC encoded genes, which directly or indirectly influence the susceptibility and resistance to HIV infection and AIDS. These genes and their mutated forms and their products which play a major role in determining the susceptibility or resistance to HIV-1 infection and AIDS. These genes have been categorized into MHC or non MHC encoded genes. The MHC encoded genes which determine HIV resistance or susceptibility are HLA-B57, HLA-B58, HLA-B27, HLA-Bw4 and HLA-A11 in Southeast Asians. On the other hand, non MHC encoded genes are CCR5, CCR2, RANTES, CXCL12, CXCR6, CCL3L1, Interleukin-10 (IL-10), and interferon gamma. The site specific mutations in these genes determine the susceptibility or resistance to HIV-1 infection and AIDS. In future the study of host genes in relation to HIV-1 infection may provide the researchers to develop newer chemotherapeutic approaches to prevent or cure HIV-1 infection effectively. 相似文献
92.
Mammalian metallothioneins (MT) have been reported to scavenge free radicals. There is no experimental evidence to show that fish MT has a similar property. In the present study cadmium-induced MT (Cd-MT) from the liver of an Indian freshwater fish Channa punctata Bloch was investigated for its free radical scavenging activity using three different in vitro assays. Exposure to cadmium chloride (0.2 mg/kg body weight; three doses on alternate days) resulted in a marked induction of Cd-MT in liver. Only a single isoform of Cd-MT was found to be induced. Molecular weight of Cd-MT was found to be 14 kDa as deduced by SDS-PAGE analysis. The purified Cd-MT effectively scavenged the following free radicals: superoxide radical (O2*-), 2,2'-azinobis 3-ethylbenzothiazoline-6-sulfonic acid (ABTS*+) and 1,1-diphenyl-picrylhydrazyl radical (DPPH*). The radical scavenging effect was found to be concentration-dependent. Also, the purified MT exhibited an inhibitory effect on ferric nitrilotriacetate (Fe-NTA) induced oxidative DNA damage in vitro. The cysteine residues of MT are proposed to be the main candidate for its radical scavenging activity. Findings of the present study strongly suggest a free radical scavenging role for fish MT. Present study adds to the little existing knowledge about fish MT and its possible biological functions. 相似文献
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Firms make positive discretionary disclosures about their environmental efforts in order to signify attention to the environmental impacts of their operations. On the one hand, firms may choose to make these disclosures to deflect attention away from other activities that may contribute negatively to their environmental performance (i.e., greenwashing in the form of the “sin of the hidden trade‐off ”). On the other hand, firms making these disclosures may legitimately improve their overall environmental performance. Our study empirically addresses the following question: Do firms that make positive discretionary environmental disclosures improve their overall environmental performance more than the firms that do not make such disclosures? Specifically, because press announcements have been shown to be a popular medium for positive discretionary disclosures, we examine the relationship between announcements in the press of firms’ environmental efforts beyond compliance, and suitably weighted‐aggregated firm‐level releases of the range of pollutants reported to the U.S. Environmental Protection Agency's Toxics Release Inventory (TRI). We employ matching methods (coarsened exact matching and propensity score matching) that account for potential sources of endogeneity, including the relationship between firms’ prior environmental performance and their propensity to disclose environmental information. Our findings from the matching methods provide encouraging evidence that greenwashing in the form of the sin of the hidden trade‐off does not appear to be prevalent. Additionally, our post hoc analysis explores factors based on the content of disclosures and industry, that may help explain differences in environmental performance among the firms making the disclosures. 相似文献
95.
Justine L. Larrouy Manpreet K. Dhami Eirian E. Jones Hayley J. Ridgway 《Environmental microbiology》2023,25(3):766-771
Flowers are an important niche for microbes, and microbes in turn influence plant fitness. As flower morphology and biology change rapidly over time, dynamic niches for microbes are formed and lost. Floral physiology at each life stage can therefore influence arrival, persistence and loss of microbial species; however, this remains little understood despite its potential consequences for host reproductive success. Through internal transcribed spacer 1 (ITS1) community profiling, we characterized the effect of transitioning through five floral stages of mānuka (Leptospermum scoparium), from immature bud to spent flower, and subsequent allocation to seed, on the flower-inhabiting fungal community. We found nectar-consuming yeasts from Aureobasidium and Vishniacozyma genera and functionally diverse filamentous fungi from the Cladosporium genus dominated the anthosphere. The candidate core microbiota persisted across this dynamic niche despite high microbial turnover, as observed in shifts in community composition and diversity as flowers matured and senesced. The results demonstrated that floral stages are strong drivers of anthosphere fungal community assembly and dynamics. This study represents the first detailed exploration of fungi through floral development, building on fundamental knowledge in microbial ecology of healthy flowers. 相似文献
96.
Phil M. Novis Manpreet Dhami Anastasija Podolyan Maya Matsumoto Robin Kodner 《Journal of phycology》2023,59(2):342-355
The quadriflagellate genus Chlainomonas frequently dominates red snow globally. It is unusual in several respects, with two separated pairs of flagella, apparent cell division via extrusion of cytoplasmic threads, and being nested phylogenetically within the biflagellate genus Chloromonas. Here, we showed that the austral species Chloromonas (Cr.) rubroleosa, originally described from Antarctic red snow, is a close biflagellate relative of Chlainomonas, challenging the monophyly of Chlainomonas as currently conceived. Sequences of the 18S rRNA gene robustly linked Cr. rubroleosa with near-identical environmental sequences from Antarctic red snow and Chlainomonas from North America, Japan, and Europe. Furthermore, the 18S rRNA and rbcL gene sequences of Cr. rubroleosa were almost identical to New Zealand and North American collections of Chlainomonas. Cr. rubroleosa and New Zealand Chlainomonas are separated by only a single-base substitution across the ITS1-5.8S-ITS2 rRNA loci (and according to ITS2, the North American collection is the next closest relative). This again raises the possibility that Chlainomonas is a life-cycle stage of vegetatively biflagellate organisms, although this remains confounded by the scarcity of biflagellates in field populations, the apparent cell division by quadriflagellates, and the absence of Chlainomonas-type cells in cultures of Cr. rubroleosa. The latter species is broadly similar to Chlainomonas, being poor at swimming, with similar pigment, chloroplast arrangement and ultrastructure, and is relatively large. Increased size is a feature of the wider clade of “Group D” snow algae. A synthesis of field and laboratory investigations may be needed to unravel the life cycle and correct the systematics of this group. 相似文献
97.
Dominic Evangelista Sabrina Simon Megan M. Wilson Akito Y. Kawahara Manpreet K. Kohli Jessica L. Ware Benjamin Wipfler Olivier Bthoux Philippe Grandcolas Frdric Legendre 《Systematic Entomology》2021,46(1):157-171
Phylogenomics seeks to use next‐generation data to robustly infer an organism's evolutionary history. Yet, the practical caveats of phylogenomics motivate investigation of improved efficiency, particularly when quality of phylogenies are questionable. To achieve improvements, one goal is to maintain or enhance the quality of phylogenetic inference while severely reducing dataset size. We approach this by assessing which kinds of loci in phylogenomic alignments provide the majority of support for a phylogenetic inference of cockroaches in Blaberoidea. We examine locus substitution rate, saturation, evolutionary divergence, rate heterogeneity, stabilizing selection, and a priori information content as traits that may determine optimality. Our controlled experimental design is based on 265 loci for 102 blaberoidean taxa and 22 outgroup species. Loci with high substitution rate, low saturation, low sequence distance, low rate heterogeneity, and strong stabilizing selection derive more support for phylogenetic relationships. We found that some phylogenetic information content estimators may not be meaningful for assessing information content a priori. We use these findings to design concatenated datasets with an optimized subsample of 100 loci. The tree inferred from the optimized subsample alignment was largely identical to that inferred from all 265 loci but with less evidence of long branch attraction, improved statistical support, and potential 4‐6x improvements to computation time. Supported by phylogenetic and morphological evidence, we erect three newly named clades (Anallactinae Evangelista & Wipfler subfam. nov., Orkrasomeria tax. nov. Evangelista, Wipfler, & Béthoux and Hemithyrsocerini Evangelista tribe nov.) and propose other taxonomic modifications. The diagnosis of Pseudophyllodromiidae Grandcolas, 1996 is modified to accommodate Anallactinae and Pseudophyllodromiinae Vickery & Kevan, 1983. The diagnosis of Ectobiidae Brunner von Wattenwyl, 1865 is modified to add novel morphological characters. 相似文献
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Vikas Kumar Kamal Rai Aneja Manpreet Kaur 《Archives Of Phytopathology And Plant Protection》2016,49(1-4):48-58
In the years 2011–2014, a series of surveys were conducted to record infestation and search natural fungal pathogens of Trianthema portulacastrum in various states of India. Among ten different agricultural important crops, heavy infestation and percentage of occurrence were observed. Gibbago trianthema, phaeodictyconidial genus, causing leaf spot disease was found on horse purslane at different districts of Haryana, Punjab and Uttar Pradesh from infected leaves and stems. Identification was confirmed on the basis of ITS rDNA sequence analysis by Macrogen Inc., Advancing through Genomics, Korea, and from CABI International Mycological Institute, England (IMI Number 502781, 502782). Sequence has been submitted to National Centre for Biotechnology Information (NCBI) with GenBank accession number KJ825852. By in vitro inoculation on Trianthema leaves, the pathogen showed similar symptoms as occurred in nature and proved Koch’s postulates. Various stages of conidia development were observed which proved the blastic-type ontogeny and porogenous development of conidiophore cell. 相似文献
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Ajay Pillarisetti Manpreet Gill Tracy Allen Sathish Madhavan Arun Dhongade Makarand Ghorpade Sudipto Roy Kalpana Balakrishnan Sanjay Juvekar Kirk R. Smith 《EcoHealth》2018,15(4):768-776
Conditional cash transfers (CCTs)—cash payments provided to households or specific household members who meet defined conditions or fulfill certain behaviors—have been extensively used in India to encourage antenatal care, institutional delivery, and vaccination. This paper describes the social design and technical development of a low-cost, meal-counting stove use monitor (the Pink Key) that enables a CCT based on liquefied petroleum gas (LPG) usage and presents pilot data from its testing and the initial deployment. The system consists of a sensing harness attached to a two-burner LPG stove and an easily removable datalogger. For each cooking event with LPG, households receive 2 rupees—less than the cost of fuel, but enough to partially defray LPG refill costs. The system could enable innovative “self-monitoring” at a large scale—participants initiate the CCT by bringing their Pink Key to antenatal clinic visits, where care providers download data and initiate payments, and participants return the sensor to their stove at home. The system aligns with existing Indian programs to improve health among poor, pregnant women, and contributes a new method to encourage the use of clean cooking technologies. 相似文献
100.
Kaur Navdeep Arora Daljit Singh Kalia Namarta Kaur Manpreet 《Molecular biology reports》2020,47(4):2901-2911
Molecular Biology Reports - An endophytic fungus Aspergillus fumigatus isolated from Moringa oleifera has been evaluated for its various bioactivities. The chloroformic fungal extract exhibited a... 相似文献