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We describe a new species of Thecadactylusfrom the Caribbean island of Sint Maarten. The new species differs from all other species in the genus by having a distinct dorsal pattern of numerous irregular but sharply deliminated black spots and blotches on an otherwise almost patternless background. 相似文献
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Vermachova M Purkrtova Z Santrucek J Jolivet P Chardot T Kodicek M 《Proteomics》2011,11(16):3430-3434
Plant seed oil bodies, subcellular lipoprotein inclusions providing storage reserves, are composed of a neutral lipid core surrounded by a phospholipid monolayer with several integrated proteins that play a significant role in stabilization of the particles and probably also in lipid mobilization. Oil bodies' proteins are generally very hydrophobic, due to the long uncharged sequences anchoring them into the lipid core, which makes them extremely difficult to handle and to digest successfully. Although oil bodies have been intensively studied during last decades, not all their proteins have been identified yet. To overcome the problems connected with their identification, a method based on SDS-PAGE, in-gel digestion and LC-MS/MS analysis was used. Digestion was carried out with trypsin and chymotrypsin, single or in combination, which increased significantly the number of identified peptides, namely the hydrophobic ones. Thanks to this methodology it was possible to achieve an extensive coverage of proteins studied, to analyze their N-terminal modifications and moreover, to detect four new oil bodies' protein isoforms, which demonstrates the complexity of oil bodies' protein composition. 相似文献
156.
Derivatives of vitamin D(3) containing a second side-chain emanating at C-20 are known as gemini and act as vitamin D receptor agonists. Recently, two of these, namely Gemini-0072 and the epimeric Gemini-0097, were selected for further studies in view of their high biological activities and lack of hypercalcemic effects. We now show that the two analogs recruit coactivator SRC-1 better than the parental gemini and act as VDR superagonists. The crystal structures of complexes of zVDR with Gemini-0072 and Gemini-0097 indicate that these ligands induce an extra cavity within the ligand-binding pocket similar to gemini and that their superagonistic activity is due to an increased stabilization of helix H12. 相似文献
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Zulato E Favaretto F Veronese C Campanaro S Marshall JD Romano S Cabrelle A Collin GB Zavan B Belloni AS Rampazzo E Naggert JK Abatangelo G Sicolo N Maffei P Milan G Vettor R 《PloS one》2011,6(4):e19081
Alström Syndrome (ALMS) is a rare genetic disorder (483 living cases), characterized by many clinical manifestations, including blindness, obesity, type 2 diabetes and cardiomyopathy. ALMS is caused by mutations in the ALMS1 gene, encoding for a large protein with implicated roles in ciliary function, cellular quiescence and intracellular transport. Patients with ALMS have extensive fibrosis in nearly all tissues resulting in a progressive organ failure which is often the ultimate cause of death. To focus on the role of ALMS1 mutations in the generation and maintenance of this pathological fibrosis, we performed gene expression analysis, ultrastructural characterization and functional assays in 4 dermal fibroblast cultures from ALMS patients. Using a genome-wide gene expression analysis we found alterations in genes belonging to specific categories (cell cycle, extracellular matrix (ECM) and fibrosis, cellular architecture/motility and apoptosis). ALMS fibroblasts display cytoskeleton abnormalities and migration impairment, up-regulate the expression and production of collagens and despite the increase in the cell cycle length are more resistant to apoptosis. Therefore ALMS1-deficient fibroblasts showed a constitutively activated myofibroblast phenotype even if they do not derive from a fibrotic lesion. Our results support a genetic basis for the fibrosis observed in ALMS and show that both an excessive ECM production and a failure to eliminate myofibroblasts are key mechanisms. Furthermore, our findings suggest new roles for ALMS1 in both intra- and extra-cellular events which are essential not only for the normal cellular function but also for cell-cell and ECM-cell interactions. 相似文献
159.
Background
Members of the subfamily Galleriinae have adapted to different selective environmental pressures by devising a unique mating process. Galleriinae males initiate mating by attracting females with either chemical or acoustic signals (or a combination of both modalities). Six compounds considered candidates for the sex pheromone have recently been identified in the wing gland extracts of Aphomia sociella males. Prior to the present study, acoustic communication had not been investigated. Signals mediating female attraction were likewise unknown.Methodology/Principal Findings
Observations of A. sociella mating behaviour and recordings of male acoustic signals confirmed that males initiate the mating process. During calling behaviour (stationary wing fanning and pheromone release), males disperse pheromone from their wing glands. When a female approaches, males cease calling and begin to produce ultrasonic songs as part of the courtship behaviour. Replaying of recorded courting songs to virgin females and a comparison of the mating efficiency of intact males with males lacking tegullae proved that male ultrasonic signals stimulate females to accept mating. Greenhouse experiments with isolated pheromone glands confirmed that the male sex pheromone mediates long-range female attraction.Conclusion/Significance
Female attraction in A. sociella is chemically mediated, but ultrasonic communication is also employed during courtship. Male ultrasonic songs stimulate female sexual display and significantly affect mating efficiency. Considerable inter-individual differences in song structure exist. These could play a role in female mate selection provided that the female''s ear is able to discern them. The A. sociella mating strategy described above is unique within the subfamily Galleriinae. 相似文献160.
Stiglmayer N Lesin M Juri J Ivanisević M Boić L Rogosić V 《Collegium antropologicum》2005,29(Z1):41-46
The aim of this study was to evaluate the efficacy of botulinum toxin-A injections on motility disturbance in patients with dysthyroid eye disease. In 36 patients (52 orbits) with active phase of Grave's ophthalmopathy with motility disturbance, botulinum toxin-A injections were applied. Ocular motility was measured before and after treatment in four main directions (elevation, depression, abduction and adduction) with F?rster perimeter. In all patients 20 units of botulinum toxin-A in one single injection was applied in the projection of the inferior rectus muscle. Statistically, the degree of upgaze increased notably in all three groups, but mostly in the first group where it amounted up to 5.8-6.0 (z = 10.0;p = 0.68). We could not prove notable increase of the motility grade in the adduction in none of the groups of the tested patients. Due to the fact that eyeball motility can be objectively measured, effect of the applied therapy can be clearly evaluated. 相似文献