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191.
Protein tyrosine kinases in bacteria are structurally and functionally distinct from their eukaryotic counterparts. The largest family of bacterial tyrosine kinases, the BY-kinase family, is highly conserved in Gram-negative and Gram-positive species, and plays a central role in biofilm and capsule formation. In Escherichia coli the BY-kinase, Wzc, is a critical component of the machinery responsible for the synthesis and export of the exo-polysaccharide colanic acid, a key constituent of biofilms. Here we present the main-chain 1HN, 15N, 13C′ and 13Cα, side-chain 13Cβ resonance assignments for a construct that encodes the entire 274-residue cytosolic catalytic domain of Wzc.  相似文献   
192.
Gene therapy is quickly becoming a reality applicable in the clinic for inherited retinal diseases. Progress over the past decade has moved proof-of-concept gene therapies from bench to bedside. The remarkable success in safety and efficacy, in the phase I/II clinical trials for the form of the severe childhood-onset blindness, Leber's Congenital Amaurosis (LCA) type II (due to mutations in the RPE65 gene) generated significant interest and opened up possibilities for a new era of retinal gene therapies. Success in these clinical trials was due to combining the favorable features of both the retina as a target organ and adeno-associated virus (AAV) as a vector. The retina offers several advantages for gene therapy approaches. It is an anatomically defined structure that is readily accessible for therapy and has some degree of immune privilege, making it suitable for application of viral vectors. AAV, on the other hand, is a non-pathogenic helper dependent virus that has little immunogenicity. This viral vector transduces quiescent cells efficiently and thanks to its small size diffuses well in the interneural matrix, making it suitable for applications in neural tissue. Building on this initial clinical success with LCA II, we have now many opportunities to extend this proof-of-concept to other retinal diseases. This article will discuss what are some of the most imminent targets for such therapies and what are the challenges that we face in moving these therapies to the clinic.  相似文献   
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194.
Ghrelin, an endogenous ligand for growth hormone secretagogue receptor, was identified in the rat stomach. This peptide acts through nitric oxide (NO) by expressing endothelial nitric oxide synthase (eNOS) and down regulating inducible nitric oxide synthase (iNOS) at its gastroproprotective effect against restraint stress induced damage. Recently the ghrelin receptor has also been detected in peripheral systems including immune tissue. We have investigated the possible effect of ghrelin on phagocytic activity of peritoneal macrophages in acute cold-restraint stress (ACRS) exposed rats. The rats were divided into control, stress and ghrelin groups. In ghrelin groups, single dose and three days consecutive dose of ghrelin (20 microg/kg. i.p.) were applied to rats that were exposed to ACRS for 4 h. 1 ml of saline was injected i.p. after ACRS for 3 consecutive days to the rats of the stress groups. Ghrelin administration reduced the increased phagocytic activity induced by ACRS. We conclude that ghrelin exerts an important role at macrophage phagocytic activity in ACRS exposed rats.  相似文献   
195.
Biological Trace Element Research - Over the past years, adipose tissue has become an invaluable source of mesenchymal stem cells (MSCs) due to development of improved isolation methodologies. In a...  相似文献   
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197.
Here, we analyze the STICHEL (STI) gene, which plays an important role in the regulation of branch number of the unicellular trichomes in Arabidopsis. We have isolated the STI locus by positional cloning and confirmed the identity by sequencing seven independent sti alleles. The STI gene encodes a protein of 1,218 amino acid residues containing a domain with sequence similarity to the ATP-binding eubacterial DNA-polymerase III gamma-subunits. Because endoreduplication was found to be normal in sti mutants the molecular function of STI in cell morphogenesis is not linked to DNA replication and, therefore, postulated to represent a novel pathway. Northern-blot analysis shows that STI is expressed in all organs suggesting that STI function is not trichome specific. The analysis of sti alleles and transgenic lines overexpressing STI suggests that STI regulates branching in a dosage-dependent manner.  相似文献   
198.
Tryptophan as a circulating precursor of serotonin (5-HT) may suppress food intake and body weight. Tryptophan administration can enhance the generation of reactive oxygen species (ROS) by inducing oxidative pathway in vivo and in vitro. We have examined the effect of repeated tryptophan administration on food consumption, body weight, brain lipid peroxidation and 5-HT immunoreactivity. Tryptophan was given at the dose of 100 mg/kg/24 hr in 0.2 ml saline solution i.p. for 7 days to mice. Control mice received 0.9% NaCL solution at the same manner and volume. Body weights were recorded at the beginning and end of the experiments. Thiobarbituric acid reactive substance (TBARS), the last product of lipid peroxidation, was measured spectrophotometrically. Brain 5-HT levels were determined by the immunohistochemical method. Our findings indicate that the tryptophan suppresses food intake significantly in mice. Body weight decreased and brain TBARS levels increased significantly by repeated tryptophan treatment. Immunohistochemical detection showed that 5-HT levels increased by tryptophan administration. There is a link between increased 5-HT level and oxidative stress by tryptophan administration on brain tissue. Tryptophan at repeated doses should be exercised carefully in clinical practice.  相似文献   
199.

Key message

Development of models to predict genotype by environment interactions, in unobserved environments, using environmental covariates, a crop model and genomic selection. Application to a large winter wheat dataset.

Abstract

Genotype by environment interaction (G*E) is one of the key issues when analyzing phenotypes. The use of environment data to model G*E has long been a subject of interest but is limited by the same problems as those addressed by genomic selection methods: a large number of correlated predictors each explaining a small amount of the total variance. In addition, non-linear responses of genotypes to stresses are expected to further complicate the analysis. Using a crop model to derive stress covariates from daily weather data for predicted crop development stages, we propose an extension of the factorial regression model to genomic selection. This model is further extended to the marker level, enabling the modeling of quantitative trait loci (QTL) by environment interaction (Q*E), on a genome-wide scale. A newly developed ensemble method, soft rule fit, was used to improve this model and capture non-linear responses of QTL to stresses. The method is tested using a large winter wheat dataset, representative of the type of data available in a large-scale commercial breeding program. Accuracy in predicting genotype performance in unobserved environments for which weather data were available increased by 11.1 % on average and the variability in prediction accuracy decreased by 10.8 %. By leveraging agronomic knowledge and the large historical datasets generated by breeding programs, this new model provides insight into the genetic architecture of genotype by environment interactions and could predict genotype performance based on past and future weather scenarios.  相似文献   
200.
Fourteen endemic and two sub-endemic species belonging to three subfamilies of Tettigoniidae (Tettigoniinae, Bradyporinae and Saginae) were sampled during field trips throughout the different ranges of Anatolia between the years of 2004 and 2013. Acoustic parameters of these 16 species affiliated to 8 genera (Anterastes, Apholidoptera, Gampsocleis, Parapholidoptera, Pezodrymadusa, Psorodonotus, Bradyporus and Saga) have been described for the first time in this study. Acoustical analysis showed that song characters are species-specific in the genera Saga and Psorodonotus. On the other hand, we could not find big differences among species of the genus Pezodrymadusa and Parapholidoptera castaneoviridis species-group.  相似文献   
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