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101.
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Oreochromis mossambicus (Peters 1852) (Tilapia) is one of the most consumed fish globally. Tilapia thrives well in environments polluted by urban waste, which invariably contain antibiotic-resistant bacteria and antibiotic resistance genes (ARGs). Thus, Tilapia surviving in such polluted environments may serve as a potential source for dissemination of ARGs. To investigate this, we isolated bacterial strains from gut of Tilapia found in polluted rivers and lakes near Pune, India, and studied the prevalence of resistance genes by molecular methods. A total of 91 bacterial strains were obtained, which include fish pathogens and human pathogens such as Aeromonas hydrophila, Klebsiella pneumoniae, E. coli, Serratia marcescens, Enterobacter spp. and Shigella spp. Overall the prevalence of class 1 integrons, class 2 integrons, extended-spectrum beta-lactamases (ESBLs) bla CTX-M, bla SHV and aac(6')-Ib-cr gene was 38%, 24%, 38%, 31% and 31% respectively. Forty-two percent of the Enterobacteriaceae strains carried bla CTX-M gene, which is a common ESBL gene in clinics. The study demonstrates that tilapia found in the polluted waters can serve as reservoirs and an alternative route for human exposure to clinically important ARG-carrying bacteria. The consumption and handling of these fish may pose a potential health risk.  相似文献   
103.
Phytochemicals of Catharanthus roseus Linn. and Tylophora indica have been known for their inhibition of malarial parasite, Plasmodium falciparum in cell culture. Resistance to chloroquine (CQ), a widely used antimalarial drug, is due to the CQ resistance transporter (CRT) system. The present study deals with computational modeling of Plasmodium falciparum chloroquine resistance transporter (PfCRT) protein and development of charged environment to mimic a condition of resistance. The model of PfCRT was developed using Protein homology/analogy engine (PHYRE ver 0.2) and was validated based on the results obtained using PSI-PRED. Subsequently, molecular interactions of selected phytochemicals extracted from C. roseus Linn. and T. indica were studied using multiple-iterated genetic algorithm-based docking protocol in order to investigate the translocation of these legends across the PfCRT protein. Further, molecular dynamics studies exhibiting interaction energy estimates of these compounds within the active site of the protein showed that compounds are more selective toward PfCRT. Clusters of conformations with the free energy of binding were estimated which clearly demonstrated the potential channel and by this means the translocation across the PfCRT is anticipated.  相似文献   
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BackgroundThe Continuing to Confront COPD International Patient Survey estimated the prevalence and burden of COPD across 12 countries. Using data from this survey we evaluated the economic impact of COPD.MethodsThis cross-sectional, population-based survey questioned 4,343 subjects aged 40 years and older, fulfilling a case definition of COPD based on self-reported physician diagnosis or symptomatology. Direct cost measures were based on exacerbations of COPD (treated and those requiring emergency department visits and/or hospitalisation), contacts with healthcare professionals, and COPD medications. Indirect costs were calculated from work loss values using the Work Productivity and Activity Impairment scale. Combined direct and indirect costs estimated the total societal costs per patient.ResultsThe annual direct costs of COPD ranged from $504 (South Korea) to $9,981 (USA), with inpatient hospitalisations (5 countries) and home oxygen therapy (3 countries) being the key drivers of direct costs. The proportion of patients completely prevented from working due to their COPD ranged from 6% (Italy) to 52% (USA and UK) with 8 countries reporting this to be ≥20%. Total societal costs per patient varied widely from $1,721 (Russia) to $30,826 (USA) but a consistent pattern across countries showed greater costs among those with increased burden of COPD (symptoms, health status and more severe disease) and a greater number of comorbidities.ConclusionsThe economic burden of COPD is considerable across countries, and requires targeted resources to optimise COPD management encompassing the control of symptoms, prevention of exacerbations and effective treatment of comorbidities. Strategies to allow COPD patients to remain in work are important for addressing the substantial wider societal costs.  相似文献   
106.
Various conditions for optimum detritylation (i.e., the removal of 5′-O-trityl protecting groups) during solid-phase synthesis of oligodeoxyribonucleotides were investigated. Di- and tri-chloroacetic acids of variable concentrations were used to study the removal of the 4,4′-dimethoxytrityl (DMTr) group. It was found that the DMTr group could be completely removed under much milder acidic conditions than what are currently used for automated solid-phase synthesis. The 2,7-dimethylpixyl (DMPx) is proposed as an alternative and more readily removable group for the protection of the 5′-OH functions both in solid- and solution-phase synthesis. The improved detritylation conditions are expected to minimize the waste and offer a protocol for incorporation of acid sensitive building-blocks in oligonucleotides.  相似文献   
107.
Despite renewed interest in the biogeography and evolutionary history of Old World tree frogs (Rhacophoridae), this family still includes enigmatic frogs with ambiguous phylogenetic placement. During fieldwork in four northeastern states of India, we discovered several populations of tree hole breeding frogs with oophagous tadpoles. We used molecular data, consisting of two nuclear and three mitochondrial gene fragments for all known rhacophorid genera, to investigate the phylogenetic position of these new frogs. Our analyses identify a previously overlooked, yet distinct evolutionary lineage of frogs that warrants recognition as a new genus and is here described as Frankixalus gen. nov. This genus, which contains the enigmatic ‘Polypedatesjerdonii described by Günther in 1876, forms the sister group of a clade containing Kurixalus, Pseudophilautus, Raorchestes, Mercurana and Beddomixalus. The distinctiveness of this evolutionary lineage is also corroborated by the external morphology of adults and tadpoles, adult osteology, breeding ecology, and life history features.  相似文献   
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Floral secretory structures have been reported for Gentianaceae; however, morphoanatomical studies of these glands are rare. We described the development and secretory activity of the colleters and nectaries throughout the floral development of Chelonanthus viridiflorus. We collected flower buds, flowers at anthesis, and fruits to be investigated using light and scanning electron microscopy. We performed histochemical tests on the secretion of colleters and used glycophyte to confirm the presence of glucose in nectar. Colleters are located on the ventral surface of sepals and nectaries occur in four regions: (i) the dorsal and (ii) ventral surfaces of sepals; (iii) apex of petals; and (iv) base of ovary. The colleters have a short peduncle and a secretory portion with homogeneous cells. They are active in flower buds and secrete polysaccharides and proteins. In flowers at anthesis, they begin to senescence presenting protoplast retraction, cell collapse, and lignification; these characteristics are intensified in fruit. The nectaries of sepals and petals have two to five cells surrounding a central cell through which the secretion is released. Nectaries are numerous, forming a nectariferous area on the dorsal surface of sepals, like that observed on petals, and can form isolated units on the ventral surface of sepals. They are active from flower buds to fruits. A region with secretory activity was identified at the base of the ovary. The secretion of colleters acts in the protection of developing organs, while nectaries are related to defenses against herbivores and the supply of nectar to potential robbers or pollinators.

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110.
Transgenic Research - Root knot nematodes are serious threats to growth and yield of solaneous crops including tomato. In this study, a binary vector carrying Remusatia vivipara...  相似文献   
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