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131.
CASP is a small cytokine-inducible protein, primarily expressed in hematopoetic cells, which associates with members of the Cytohesin/ARNO family of guanine nucleotide-exchange factors. Cytohesins activate ARFs, a group of GTPases involved in vesicular initiation. Functionally, CASP is an adaptor protein containing a PDZ domain, a coiled-coil, and a potential carboxy terminal PDZ-binding motif that we sought to characterize here. Using GST pulldowns and mass spectrometry we identified the novel interaction of CASP and sorting nexin 27 (SNX27). In lymphocytes, CASP's PDZ-binding motif interacts with the PDZ domain of SNX27. This protein is a unique member of the sorting nexin family of proteins, a group generally involved in the endocytic and intracellular sorting machinery. Endogenous SNX27 and CASP co-localize at the early endosomal compartment in lymphocytes and also in transfection studies. These results suggest that endosomal SNX27 may recruit CASP to orchestrate intracellular trafficking and/or signaling complexes.  相似文献   
132.
Lymphedema-distichiasis (LD) is a dominantly inherited syndrome with onset of lymphedema at or just after puberty. Most affected individuals have distichiasis-fine hairs arising inappropriately from the eyelid meibomian glands-which is evident from birth. A study of three families with LD has shown linkage to chromosome 16q24.3, and subsequent analysis of the region for recombinant genes places the locus between D16S422 and D16S3074, a distance of approximately 16 cM. Possible candidate genes in this interval include the N-proteinase for type 3 collagen, PCOLN3; the metalloprotease PRSM1; and the cell matrix-adhesion regulator, CMAR.  相似文献   
133.
Keloid scarring is a dermal fibroproliferative response characterized by excessive and progressive deposition of collagen; aetiology and molecular pathology underlying keloid formation and progression remain unclear. Genetic predisposition is important in the pathogenic processes of keloid formation, however, environmental factors and epigenetic mechanisms may also play pivotal roles. Epigenetic modification is a recent area of investigation in understanding the molecular pathogenesis of keloid scarring and there is increasing evidence that epigenetic changes may play a role in induction and persistent activation of fibroblasts in keloid scars. Here we have reviewed three epigenetic mechanisms: DNA methylation, histone modification and the role of non‐coding RNAs. We also review the evidence that these mechanisms may play a role in keloid formation ‐ in future, it may be possible that epigenetic markers may be used instead of prognostic or diagnostic markers here. However, there is a significant amount of work required to increase our current understanding of the role of epigenetic modification in keloid disease.  相似文献   
134.
The Common Pheasant Phasianus colchicus is widely distributed in temperate to subtropical regions of the Palaearctic realm. Populations of Common Pheasant have been classified into five subspecies groups based on morphological variations in male plumage. Previous phylogeographical studies have focused on limited sets of subspecies groups in the eastern Palaearctic and knowledge on subspecies in the western Palaearctic region is still poor. In this study, we undertake the first comprehensive analysis of subspecies from all five defined subspecies groups across the entire Palaearctic region. Two mitochondrial (CYTB and CR) and two nuclear (HMG and SPI) loci were used to investigate genetic relationships of these subspecies groups and to infer their dispersal routes. Our results revealed that the subspecies elegans, with its range in northwestern Yunnan, China, was in the basal position among 17 studied subspecies, supporting a previous hypothesis that the Common Pheasant most probably originated in forests in southeastern China. Subspecies in the western Palaearctic region nested within the most subspecies‐rich torquatus group (‘Grey‐rumped Pheasants’), indicating that the torquatus group is not a clade but instead forms a gradation with other subspecies and subspecies groups. Our dating analysis suggested that the initial divergence among populations of Common Pheasant originated around 3.4 Mya with subsequent dispersal into the Western Palaearctic region during the Late Pliocene–Lower Pleistocene approximately 2.5–1.8 Mya. We propose two possible east‐to‐west colonization routes for the Common Pheasant and suggest conservation implications for some regional subspecies. Overall, this study demonstrates the lack of concordance between morphology‐based subspecies delimitation and their genetic relationships. This is likely to be a consequence of initial isolation due to historical vicariance followed by population admixture due to recent range expansion of Common Pheasant in the western Palaearctic region.  相似文献   
135.
In this study the cold tolerance potential of three Vitis vinifera cultivars including ‘Red Sultana’, ‘White Sultana,’ and ‘Flame Seedless’ was evaluated under greenhouse condition. After 15 leaves stage in average, the grapevine plants were subjected to cold stress regimes (4, 0 and ? 4 °C) and compared with control plants (24 °C). A clear increase in leaf electrolyte leakage (EL), thiobarbituric acid reactive substances (TBARS), and H2O2 concentrations was observed with decreasing temperature from 4 to ? 4 °C in all grapevine cultivars. Chilled plants showed marked increases in their abscisic acid (ABA), soluble sugars, and proline contents in compared to control vines. Upon exposure to cold stress, the EL, TBARS, H2O2, and relative water content of ‘Red Sultana’ were found to be lower compared to ‘White Sultana’ and ‘Flame Seedless’. Under 0 °C condition, ‘Red Sultana’ had the highest superoxide dismutase, guaiacol peroxidase and catalase activities, which was approximately twofold higher than those of all other cultivars. Soluble sugars such as glucose, fructose, and sucrose increased from 4 to ? 4 °C. These increments were higher in ‘Red Sultana’ compared to other cultivars which was concomitant with higher accumulation of endogenous ABA concentration in this cultivar. Higher accumulation of ABA and soluble sugars in ‘Red Sultana’ confirmed the key roles of these compounds in cold tolerance which could be applied as a cold tolerance marker for early selection of grapevine cultivars with the aim to establish vineyards in cold winter regions.  相似文献   
136.
Polysaccharides, which have been explored to possess gelling properties and a wide margin of safety, were used to formulate single-unit floating matrix tablets by a direct compression technique. This work has the aim to allow continuous slow release of famotidine above its site of absorption. The floating approach was achieved by the use of the low density polypropylene foam powder. Polysaccharides (κ-carrageenan, gellan gum, xyloglucan, and pectin) and blends of polysaccharides (κ-carrageenan and gellan gum) and cellulose ethers (hydroxypropylmethyl cellulose, hydroxypropylcellulose, sodium carboxymethyl cellulose) were tried to modulate the release characteristics. The prepared floating tablets were evaluated for their floating behavior, matrix integrity, swelling studies, in vitro drug release studies, and kinetic analysis of the release data. The differential scanning calorimetry and Fourier transform infrared spectroscopy studies revealed that changing the polymer matrix system by formulation of polymers blends resulted in formation of molecular interactions which may have implications on drug release characteristics. This was obvious from the retardation in drug release and change in its mechanistics.  相似文献   
137.
New analogues of the potent antihelmintic meclonazepam were prepared and evaluated against Schistosoma mansoni. The biological data suggests substitution at positions 2 and 4 of meclonazepam could provide promising analogues for prophylactic and therapeutic activity against S. mansoni.  相似文献   
138.
Milroy disease (hereditary lymphoedema type I, MIM 153100) is a congenital onset primary lymphoedema with autosomal dominant inheritance. Mutations in the gene, vascular endothelial growth factor receptor 3, VEGFR3 (FLT4), are known to cause Milroy disease, but there is uncertainty about the prevalence of VEGFR3 mutations in patients with primary lymphoedema and more specifically in those with a phenotype that resembles Milroy disease. This study aims to address this issue and thereby delineate the Milroy disease phenotype. Fifty-two patients with primary lymphoedema were analysed for mutations in the coding regions of VEGFR3. Patients were divided into four groups: Typical Milroy disease with family history (group I), typical Milroy disease with no family history (group II), atypical Milroy disease (group III), and complex primary lymphoedema (group IV). Results demonstrated that with rigorous phenotyping the likelihood of detecting VEGFR3 mutations is optimised. Mutation prevalence is 75% in typical Milroy patients with a family history (group I) and 68% if positive family history is not a diagnostic criterion. A positive family history is not essential in Milroy disease. The likelihood of detecting VEGFR3 mutations in patients who have a phenotype which is not typical of Milroy disease is very small (<5%). For the 22 mutation positive patients, 14 novel VEGFR3 mutations were identified, two of which were in exon 22 and one in exon 17, confirming that these exons should be included in VEGFR3 analysis. No mutations were found outside the kinase domains, showing that analysis of this part of the gene is not useful for Milroy disease patients. VEGFC, which encodes the ligand for VEGFR3, was sequenced in all patients with typical Milroy disease (groups I and II) and no mutations were identified. F. C. Connell and P. Ostergaard contributed equally to this work. An erratum to this article can be found at  相似文献   
139.
HIV-protease inhibitors (PIs) markedly decreased mortality of HIV-infected patients. However, their use has been associated with occurence of metabolic abnormalities the causes of which are not well understood. We report here that lopinavir, one of the most prescribed PI, dose-dependently co-induced insulin resistance and ER stress in human adipocytes obtained from differentiation of precursor cells.Insulin resistance was subsequent to IRS1 phosphorylation defects and resulted in a concentration-dependent decrease of glucose uptake. The major ER stress pathway involved was the phosphorylation of eIF2-α. Salubrinal, a selective eIF2-α dephosphorylation inhibitor, induced insulin resistance by targeting IRS1 phosphorylation at serine 312 and acted synergistically with LPV when both drugs were used in combination.This study points out the key role of eIF2-α phosphorylation in the development of PI-associated insulin resistance and ER stress. Thus, this protein represents a promising therapeutic target for development of new PIs devoid of adverse metabolic effects.  相似文献   
140.
During red wine fermentation, high temperatures may cause stuck fermentation by affecting the physiology of fermenting yeast. This deleterious effect is the result of the complex interaction of temperature with other physicochemical parameters of grape juice, such as sugar and lipid content. The genetic background of fermenting yeast also interacts with this complex matrix and some strains are more resistant to high temperatures than others. Here, the temperature tolerance of nine commercial starters was evaluated, demonstrating that, at high sugar concentrations, half of them are sensitive to temperature. Using a classical backcross approach, one thermo-sensitive commercial starter was genetically improved by introducing quantitative trait loci conferring resistance to temperature. With this breeding program it is possible to obtain a thermo-resistant strain sharing most of its genome with the initial commercial starter. The parental and improved strains were compared for population growth and fermentation ability in various conditions. Despite their common genetic background, these two strains showed slight physiological differences in response to environmental changes that enable identification of the key physiological parameters influencing stuck fermentation.  相似文献   
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