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81.

Background  

Adverse drug reactions (ADRs) are now recognized as an important cause of hospital admissions, with a proportion ranging from 0.9–7.9%. They also constitute a significant economic burden. We thus aimed at determining the prevalence and the economic burden of ADRs presenting to Medical Emergency Department (ED) of a tertiary referral center in India  相似文献   
82.
83.
Ludwigia adscendens (L.) Hara, Ludwigia parviflora Roxb., and Ludwigia octovalvis (Jacq.) Raven (Onagraceae) are abundant weeds in rice fields in India. These weeds compete with rice for resources in fields and this results in reduction of grain yield. Altica cyanea (Weber) (Coleoptera: Chrysomelidae) is a biocontrol agent of the three rice-field weeds. Hence, it is relevant to study host preference of A. cyanea using volatile cues of these three weeds. Therefore, we attempted to identify volatiles from leaves of the three Ludwigia species attracting A. cyanea, which could be used as an attractant during early emergence of the weeds in rice fields. In Y-tube olfactometer assays, A. cyanea females were more attracted to natural volatiles of plants after 48 h of feeding by adults than to volatiles of undamaged plants. The volatile organic compounds from undamaged plants, and plants after 6 and 48 h of feeding by A. cyanea were identified and quantified by gas chromatography and mass spectrometry (GC–MS) and GC-flame ionization detection (FID), respectively. In total, 25, 29, and 29 volatile compounds were detected in headspaces of undamaged L. adscendens, L. parviflora, and L. octovalvis, respectively, whereas 32, 35, and 34 compounds, respectively, were detected after 48 h of feeding by A. cyanea. Methyl jasmonate predominated among the volatile compounds in all treatments, but this compound was not attractive to A. cyanea. Females were attracted by synthetic blends of 3-hexanol, α-pinene, linalool oxide, and phytol in amounts mimicking those in each of the three Ludwigia species after 48 h of feeding by A. cyanea. The blends mimicking L. adscendens and L. parviflora included geraniol, whereas the blend mimicking L. parviflora also included 1-tridecanol. These synthetic blends may be helpful to monitor A. cyanea in biocontrol programmes.  相似文献   
84.
85.
Textile effluent is generally complicated to manage because of its extremely noxious and recalcitrant coloured compositions. Mycoremediation is an extensively used strategy for the competent degradation of hazardous pollutants present in textile effluent. Fungus could be immobilized in synthetic or natural matrices. The current study shows the decolourization of the textile effluent by 85·5 and 98·5% within 6 h using suspended and immobilized fungus, Geotrichum candidum with optimized parameters like inoculum size (5%), pH (4·5), and temperature (30°C). To maintain a high biomass of fungal population and enhance the retention of fungal strain in the contaminated sites, the fungi need to be immobilized. Hence, the fungus was immobilized naturally onto the selected inert support that is, coconut fibres by the means of adsorption, where they grew as active films on the fibres after being grown in the culture broth. The optimized process parameters of inoculum size, fibre quantity and agitation speed for immobilized G. candidum were 5%, 2·2 g l−1 of effluent and 100 rev min−1 respectively. High level of laccase (22 and 25 U l−1 in suspended and immobilized fungal cells treatment respectively) was observed during the process of decolourization and it was found that decolourization was directly proportional to the laccase activity. The UV–vis, FTIR, 1H NMR and GC-MS analyses of treated textile industrial wastewater revealed the degradation of toxic pollutants in the textile effluent and formation of lower molecular weight intermediates. The study revealed a higher efficacy of immobilized G. candidum in comparison to suspended fungal culture, employing ligninolytic enzyme laccase, which catalyzes the degradation/transformation of aromatic dyes in the textile effluent thus decolourizing it.  相似文献   
86.
The aim of the present study was investigation of the effects of fly ash and mining soil on growth and antioxidant protection of two cultivars of Indian wild rice (Oryza nivara and Oryza rufipogon) for possible phytoremediation and restoration of metal-contaminated site. In this study, Indian wild rice showed significant changes in germination, growth, and biochemical parameters after exposure to different ratio of fly ash and mining soil with garden soil. There was significant reduction of germination, fresh weight, dry weight, leaf chlorophyll content, leaf area, Special Analysis Device Chlorophyll (SPAD) Index, proteins, and activities of antioxidant enzymes in both cultivars of the wild rice grown in 100% fly ash and mining soil compared to the plants grown in 100% garden soil. Results from this study showed that in both cultivars of wild rice, all growth and antioxidant parameters increased when grown in 50% fly ash and mining soil. Taken together, Indian wild rice has the capacity to tolerate 50% of fly ash and mining soil, and can be considered as a good candidate for possible phytoremediation of contaminated soils.  相似文献   
87.
RNA viruses are characterized by high mutation rates that give rise to populations of closely related genomes, known as viral quasispecies. Underlying heterogeneity enables the quasispecies to adapt to changing conditions and proliferate over the course of an infection. Determining genetic diversity of a virus (i.e., inferring haplotypes and their proportions in the population) is essential for understanding its mutation patterns, and for effective drug developments. Here, we present QSdpR, a method and software for the reconstruction of quasispecies from short sequencing reads. The reconstruction is achieved by solving a correlation clustering problem on a read-similarity graph and the results of the clustering are used to estimate frequencies of sub-species; the number of sub-species is determined using pseudo F index. Extensive tests on both synthetic datasets and experimental HIV-1 and Zika virus data demonstrate that QSdpR compares favorably to existing methods in terms of various performance metrics.  相似文献   
88.

Background  

The malarial parasite, Plasmodium falciparum (Pf), is responsible for nearly 2 million deaths worldwide. However, the mechanisms of cellular signaling in the parasite remain largely unknown. Recent discovery of a few protein kinases and phosphatases point to a thriving reversible phosphorylation system in the parasite, although their function and regulation need to be determined.  相似文献   
89.
Phosphorylation of the hepatitis delta virus antigens.   总被引:2,自引:2,他引:0       下载免费PDF全文
V Bichko  S Barik    J Taylor 《Journal of virology》1997,71(1):512-518
We used two-dimensional electrophoresis (nonequilibrium pH gradient electrophoresis followed by sodium dodecyl sulfate-10% polyacrylamide gel electrophoresis) coupled with 32P labeling and immunoblotting detection with 125I-protein A to detect and quantitate phosphorylation of the large and small forms of the delta antigen (deltaAg-L and deltaAg-S, respectively). Analysis of deltaAg species from the serum and liver of an infected woodchuck as well as deltaAg species expressed in and secreted from transfected Huh7 cells revealed the following. (i) No detectable phosphorylation of deltaAg-S occurred. (ii) In virions from the serum of an infected animal and in the particles secreted from cotransfected cells, none of the deltaAg-L was phosphorylated. (iii) Only in the infected liver and in transfected cells was any phosphorylation detected; it corresponded to a monophosphorylated form of deltaAg-L. Given these results, we carried out serine-to-alanine mutagenesis of the deltaAg-L to determine whether the monophosphorylation was predominantly at a specific site on the unique 19-amino-acid (aa) extension. We mutated each of the two serines, aa 207 and 210, on this extension and also the serine at aa 177. These three mutations had no significant effect on phosphorylation. In contrast, mutagenesis to alanine of the cysteine at aa 211, which normally acts as the acceptor for farnesylation, completely inhibited phosphorylation. Our interpretation is that the site(s) of phosphorylation is probably not in the 19-aa extension unique to deltaAg-L and that phosphorylation of deltaAg-L may depend upon prior farnesylation. The possible significance of the intracellular phosphorylated forms of deltaAg-L is discussed.  相似文献   
90.
Movement-deficient potato virus X (PVX) mutants tagged with the green fluorescent protein were used to investigate the role of the coat protein (CP) and triple gene block (TGB) proteins in virus movement. Mutants lacking either a functional CP or TGB were restricted to single epidermal cells. Microinjection of dextran probes into cells infected with the mutants showed that an increase in the plasmodesmal size exclusion limit was dependent on one or more of the TGB proteins and was independent of CP. Fluorescently labeled CP that was injected into epidermal cells was confined to the injected cells, showing that the CP lacks an intrinsic transport function. In additional experiments, transgenic plants expressing the PVX CP were used as rootstocks and grafted with nontransformed scions. Inoculation of the PVX CP mutants to the transgenic rootstocks resulted in cell-to-cell and systemic movement within the transgenic tissue. Translocation of the CP mutants into sink leaves of the nontransgenic scions was also observed, but infection was restricted to cells close to major veins. These results indicate that the PVX CP is transported through the phloem, unloads into the vascular tissue, and subsequently is transported between cells during the course of infection. Evidence is presented that PVX uses a novel strategy for cell-to-cell movement involving the transport of filamentous virions through plasmodesmata.  相似文献   
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