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191.
The tentative elucidation of the 3D-structure of vitellogenesis inhibiting hormone (VIH) peptides is conversely underprivileged by difficulties in gaining enough peptide or protein, diffracting crystals, and numerous extra technical aspects. As a result, no structural information is available for VIH peptide sequences registered in the Genbank. In this situation, it is not surprising that predictive methods have achieved great interest. Here, in this study the molt-inhibiting hormone (MIH) of the kuruma prawn (Marsupenaeus japonicus) is used, to predict the structure of four VIHrelated peptides in the crustacean species. The high similarity of the 3D-structures and the calculated physiochemical characteristics of these peptides suggest a common fold for the entire family.  相似文献   
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193.
In mammalian cells, endocytosis of the fluid phase and glycosylphosphatidylinositol-anchored proteins (GPI-APs) forms GEECs (GPI-AP enriched early endosomal compartments) via an Arf1- and Cdc42-mediated, dynamin independent mechanism. Here we use four different fluorescently labeled probes and several markers in combination with quantitative kinetic assays, RNA interference and high resolution imaging to delineate major endocytic routes in Drosophila cultured cells. We find that the hallmarks of the pinocytic GEEC pathway are conserved in Drosophila and identify garz, the fly ortholog of the GTP exchange factor GBF1, as a novel component of this pathway. Live confocal and TIRF imaging reveals that a fraction of GBF1 GFP dynamically associates with ABD RFP (a sensor for activated Arf1 present on nascent pinosomes). Correspondingly, a GTP exchange mutant of GBF1 has altered ABD RFP localization in the evanescent field and is impaired in fluid phase uptake. Furthermore, GBF1 activation is required for the GEEC pathway even in the presence of Brefeldin A, implying that, like Arf1, it has a role in endocytosis that is separable from its role in secretion.  相似文献   
194.
An enhanced intracellular level of Nitric oxide (NO) is essential to ameliorate several pathological conditions of heart and vasculature necessitating the activation of NOS. We have projected in this report the acetylation of eNOS by polyphenolic peracetates (PA) catalyzed by the novel enzyme acetoxy drug: protein transacetylase (TAase) discovered in our laboratory as an unambiguous way of activating NOS which results in the manifestation of physiological action. The human platelet was chosen as the experimental system in order to validate the aforementioned proposition. PA caused profound irreversible activation of platelet NADPH cytochrome c reductase mediated by TAase. The convincing biochemical evidences are presented to show that PA could cause acetylation of the reductase domain of NOS leading to the activation of eNOS in tune with their specificities to platelet TAase. As a result, the enhanced level of NO due to activation of platelet eNOS by PA was found to inhibit the ADP-induced platelet aggregation. The present studies highlight for the first time the role of PA as the novel potent agent for enhancing the intracellular NO levels.  相似文献   
195.
The aim of this study is to examine the association of BMI and waist circumference (WC), with a quality of life (QoL) indicator designed for older ages (CASP19), and with depressive symptoms (Centre for Epidemiologic Studies Depression Scale). We included 8,688 individuals aged ≥52 years who participants of Wave 2 (2004–2005) and Wave 3 (2006–2007) of the English Longitudinal Study of Ageing (ELSA). To explore cross‐sectional relationships (2004–2005), we fitted regression models for BMI and WC (included simultaneously) as our predictors of QoL and depressive symptoms adjusted for covariates. To explore longitudinal relationships, BMI and waist at baseline (2004–2005) were related to the each outcome variable measured at follow‐up (2006–2007), and adjusted for baseline characteristics (2004–2005). For a given BMI, larger WC was associated with lower QoL and higher risk of depressive symptoms for women in cross‐sectional and longitudinal analyses. By contrast for a given WC increased BMI for women was positively associated with QoL and lower odds of depressive symptoms. In men, for a given BMI, increased WC was related to QoL only cross‐sectionally; neither WC nor BMI at baseline were associated with depressive symptoms (cross‐sectionally or longitudinally). In conclusion among older people, for a given BMI, increased WC was related with higher risk of poor QoL and, for women, of depressive symptoms; whereas for a given WC, increased BMI had a protective effect on QoL for women.  相似文献   
196.
The present study aimed at identifying the fluoride-endemic areas in five different blocks in Agra district, Uttar Pradesh, India. A total of 365 groundwater samples from 73 villages were analyzed for establishing the concentration range of fluoride in drinking water. The fluoride level in the study area varied from 0.14 to 4.88 mg/L. Out of 73, the fluoride levels in 45 villages did not meet the permissible Word Health Organization standards. The Baroli Ahir block was found the highly fluoride-endemic area followed by Saiyan, Bichpuri, Achnera and Etmadpur. Chronic daily intake of fluoride in adults was 1.25 and 1.5 times higher than those in children and infants, respectively. The probability of dental fluorosis in infants was higher (42%) while adults were more prone to bone and skeletal fluorosis (60%). The hazard quotient analysis revealed that children were found to be at maximum risk followed by infants and adults. Sensitivity analysis revealed that the fluoride concentration is the major influencing parameter responsible for different types of fluorosis in various age groups.  相似文献   
197.
Single nucleotide polymorphisms (SNPs) are becoming the most amenable form of DNA-based molecular markers for genetic analysis. In hexaploid bread wheat (Triticum aestivum L.), it is difficult to discern true polymorphic SNPs due to homoeologous and paralogous genes. Two serial analysis of gene expression (SAGE) libraries were developed utilizing leaves from resistant plants carrying leaf rust resistance gene Lr28; one library was derived from leaves that were mock inoculated and the other was derived from leaves inoculated with the urediniospores of the leaf rust pathogen Puccinia triticina. Next-generation sequencing reads, after quality trimming and removal of fungal sequences, were mapped to wheat reference sequences at Ensembl Plants. CLC Genomics Workbench and Freebayes softwares were employed for SNP calling. A total of 611 SNPs were predicted to be common by both softwares, of which 207 varietal SNPs were identified by ConservedPrimer software. A subset of 100 SNPs was used for validation across 47 wheat genotypes using Kompetitive Allele Specific PCR (KASP) assay; 83 SNPs could be successfully validated. These SNPs were positioned on wheat subgenomes and chromosome arms. When functionally annotated, many sequences harboring SNPs showed homology to resistance and resistance-like genes listed in Plant Resistance Gene database (PRGdb) as well as pathogenesis-related (PR) and stress-responsive genes. The results of the present study involving discovery of SNPs associated with resistance to leaf rust, a major threat to wheat production worldwide, will be valuable for molecular breeding for rust resistance.  相似文献   
198.
Amycolatopsis mediterranei S699 is an actinomycete that produces an important antibiotic, rifamycin B. Semisynthetic derivatives of rifamycin B are used for the treatment of tuberculosis, leprosy, and AIDS-related mycobacterial infections. Here, we report the complete genome sequence (10.2 Mb) of A. mediterranei S699, with 9,575 predicted coding sequences.  相似文献   
199.
Intertidal alga Gracilaria corticata growing in natural environment experiences various abiotic stresses during the low tides. The aim of this study was to determine whether desiccation exposure would lead to oxidative stress and its effect varies with exposure periods. This study gives an account of various biochemical changes in G. corticata following the exposure to desiccation for a period of 0 (control), 1, 2, 3 and 4 h under controlled conditions. During desiccation, G. corticata thalli showed dramatic loss of water by almost 47% when desiccated for 4 h. The enhanced production of reactive oxygen species (ROS) and increased lipid peroxidation observed during the exposure of 3-4 h were chiefly contributed by higher lipoxygenase (LOX) activity with the induction of two new LOX isoforms (LOX-2, ∼85 kDa; LOX-3, ∼65 kDa). The chlorophyll, carotenoids and phycobiliproteins (phycoerythrin and phycocyanin) were increased during initial 2 h exposure compared to control and thereafter declined in the succeeding exposure. The antioxidative enzymes such as superoxide dismutase (SOD), ascorbate peroxidase (APX), glutathione reductase (GR), glutathione peroxidase (GPX) and the regeneration rate of reduced ascorbate (AsA) and glutathione (GSH) increased during desiccation up to 2-3 h. Further, the isoforms of antioxidant enzymes Mn-SOD (∼150 kDa), APX-4 (∼110 kDa), APX-5 (∼45 kDa), GPX-1 (∼80 kDa) and GPX-2 (∼65 kDa) responded specifically to the desiccation exposure. Compared to control, a relative higher content of both free and bound insoluble putrescine and spermine together with enhanced n-6 PUFAs namely C20:4(n-6) and C20:3(n-6) fatty acids found during 2 h exposure reveals their involvement in defence reactions against the desiccation induced oxidative stress.  相似文献   
200.
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