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211.
The relative suitability of five instars of Diaphania indica (Saunders) (Lepidoptera: Pyralidae) as a substrate for the development of a larval parasitoid, Apanteles stantoni Ashmead (Hymenoptera: Braconidae), was investigated. Maximum parasitism (22.25?±?1.21%) under laboratory conditions was observed in the early larval instars. The highest parasitoid emergence was recorded from the second (86.07?±?0.70%) and third (98.93?±?0.72%) instar larvae of D. indica, and that from the first larvae was 71.43?±?1.18%. The number of cocoons in each cluster, length and width of single cocoons, percentage emergence, sex ratio and adult longevity of A. stantoni collected from different instars of D. indica were also recorded. These results indicated that the life stage of the host when the parasitoid larvae complete their final instar is particularly important for their development. Therefore, considering the efficiency of parasitism and reproduction, the second-instar larvae of D. indica is the most suitable stage for mass rearing A. stantoni in the laboratory.  相似文献   
212.
Coronavirus disease 2019 (COVID-19) pandemic has uprooted our lives like never before since its onset in the late December 2019. The world has seen mounting infections and deaths over the past few months despite the unprecedented measures countries are implementing, such as lockdowns, social distancing, mask-wearing, and banning gatherings in large groups. Interestingly, young individuals seem less likely to be impacted by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus responsible for COVID-19. While the rate of transmission, symptom presentation, and fatality is lower in children than people from other age groups, they have been disproportionately affected by strict lockdown measures needed to curb viral spread. In this review, we describe the association between patient age and COVID-19, epidemiology of SARS-CoV-2 infection in children, psychological effects associated with lockdowns and school closures, and possible mechanisms underlying lower transmission rate of COVID-19 in children.  相似文献   
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Aquaporins (AQPs) are integral membrane channels that facilitate the bidirectional transport of water and sometimes other small solutes across biological membranes. AQPs are important in mediating environmental adaptations in mosquitoes and are considered as a novel target for the development of effective insecticides against mosquitoes. Here, we expressed Aedes aegypti AQP6 ( AaAQP6) in human embryonic kidney (HEK) 293 cells and analyzed the water permeability by a conventional swelling assay, that is, a real‐time change in cell size corresponding to the cell swelling induced by hyposmotic solution. The swelling assay revealed that AaAQP6 is a mercury‐sensitive water channel. Gene expression studies showed that AaAQP6 is highly expressed in the pupae than other developmental stages. Heterologous expression of AaAQP6 in HEK cell was mainly observed intracellularly suggesting AaAQP6 possibly could be a subcellular water channel and may play an osmoregulatory function in the pupae of A. aegypti.  相似文献   
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It is of interest to document the molecular docking analysis of Cyclin-dependent kinase 1 (CDK-1) inhibitors from Chrysophyllum cainito leaves towards the treatment of tumors using the known structure of PDB ID: 5HQ0. Data shows that molecules such as 8- (Dimethylamino)-7-(3-(4-ethylphenoxy)-2d, ethyl 6-oxo-5-propylheptanoate, 2,3-dihydro-3, 5-dihydroxy-6-methyl-4h-pyran-4-one, 1,2,3-benzenetriol and 1,4-benzenediol 2,5-bis (1,1-dimethylethyl) identified in methanolic extract of C. cainito have binding features with CDK1 for further consideration.  相似文献   
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Tuberculosis (TB) remains a worldwide problem and the need for new drugs is increasingly more urgent with the emergence of multidrug- and extensively-drug resistant TB. Inosine 5’-monophosphate dehydrogenase 2 (IMPDH2) from Mycobacterium tuberculosis (Mtb) is an attractive drug target. The enzyme catalyzes the conversion of inosine 5’-monophosphate into xanthosine 5’-monophosphate with the concomitant reduction of NAD+ to NADH. This reaction controls flux into the guanine nucleotide pool. We report seventeen selective IMPDH inhibitors with antitubercular activity. The crystal structures of a deletion mutant of MtbIMPDH2 in the apo form and in complex with the product XMP and substrate NAD+ are determined. We also report the structures of complexes with IMP and three structurally distinct inhibitors, including two with antitubercular activity. These structures will greatly facilitate the development of MtbIMPDH2-targeted antibiotics.  相似文献   
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International Journal of Peptide Research and Therapeutics - The antioxidant and antibacterial potential of various solvent extracts (water, 100% and 80% methanol) of Perna viridis was evaluated....  相似文献   
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Quercitrin, a bio flavonoid, was investigated for its antioxidant potential in streptozotocin (STZ)-induced diabetic rats. Rats were induced diabetic by a single intraperitoneal injection of streptozotocin (50 mg/kg). The levels of fasting plasma glucose and insulin were estimated. Lipid peroxidative products and antioxidants were estimated in pancreas, liver, and kidney. Histopathological studies were carried out in these tissues. A significant (P < 0.05) increase in the levels of fasting plasma glucose and lipid peroxidative products (thiobarbituric acid reactive substances and lipid hydroperoxides) and a significant (P < 0.05) decrease in plasma insulin, enzymic antioxidants (superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase), and nonenzymic antioxidants (reduced glutathione, vitamin C, and E) in diabetic pancreas, liver, and kidney were observed. Oral administration of quercitrin (30 mg/kg) for a period of 30 days significantly (P < 0.05) decreased fasting plasma glucose, increased insulin levels, and improved the antioxidant status of diabetic rats by decreasing lipid peroxidative products and increasing enzymic and nonenzymic antioxidants. Normal rats treated with quercitrin (30 mg/kg) showed no significant (P < 0.05) effect on any of the parameters studied. Histopathological studies of the pancreas, liver, and kidney showed the protective role of quercitrin. Thus, our study clearly shows that quercitrin has antioxidant effect in STZ-induced experimental diabetes.  相似文献   
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