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71.
The synthesis of the untriakontapeptide β-endorphin is described. The synthetic peptide is shown to possess opiate activity comparable with that of the natural product by the opiate receptor binding assay.  相似文献   
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Seventy-three N,N-disubstituted amides of long-chain, principally C(18), fatty acids were screened for antimicrobial activity against bacteria, yeasts, and molds. Amides containing an epoxy group exhibit a broad spectrum of antimicrobial activity which is further enhanced by unsaturation. Mono-unsaturation alone does not contribute a broad level of activity to the N,N-disubstituted amides of the C(18) fatty acids.  相似文献   
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During the acute phase of a severe burn, surgery is an emergency. In this situation, human skin allografts constitute an effective temporary skin substitute. However, information about the use of human tissue can not be given to the patients because most of the allografted patients are unconscious due to their injury. This study explored the restitution of information on skin donation to patients who have been skin allografted and who have survived their injury. A qualitative study was conducted due to the limited number of patients in ability to be interviewed according to our medical and psychological criteria. 12 patients who had been treated between 2002 and 2008 were interviewed. Our results show that 10 of them ignored that they had received skin allografts. One of the two patients who knew that they had received allografts knew that skin had been harvested from deceased donor. All patients expressed that there is no information that should not be delivered. They also expressed their relief to have had the opportunity to discuss their case and at being informed during their interview. Their own experience impacted their view in favor of organ and tissue donation.  相似文献   
76.
Oceanobacillus massiliensis strain N’DiopT sp. nov. is the type strain of O. massiliensis sp. nov., a new species within the genus Oceanobacillus. This strain, whose genome is described here, was isolated from the fecal flora of a healthy patient. O. massiliensis is an aerobic rod. Here we describe the features of this organism, together with the complete genome sequence and annotation. The 3,532,675 bp long genome contains 3,519 protein-coding genes and 72 RNA genes, including between 6 and 8 rRNA operons.  相似文献   
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Genome scans in recently separated species can inform on molecular mechanisms and evolutionary processes driving divergence. Large‐scale polymorphism data from multiple species pairs are also key to investigate the repeatability of divergence—whether radiations tend to show parallel responses to similar selection pressures and/or underlying molecular forces. Here, we used whole‐genome resequencing data from six wood white (Leptidea sp.) butterfly populations, representing three closely related species with karyomorph variation, to infer the species' demographic history and characterize patterns of genomic diversity and differentiation. The analyses supported previously established species relationships, and there was no evidence for postdivergence gene flow. We identified significant intraspecific genetic structure, in particular between karyomorph extremes in the wood white (L. sinapis)—a species with a remarkable chromosome number cline across the distribution range. The genomic landscapes of differentiation were erratic, and outlier regions were narrow and dispersed. Highly differentiated (FST) regions generally had low genetic diversity (θπ), but increased absolute divergence (DXY) and excess of rare frequency variants (low Tajima's D). A minority of differentiation peaks were shared across species and population comparisons. However, highly differentiated regions contained genes with overrepresented functions related to metabolism, response to stimulus and cellular processes, indicating recurrent directional selection on a specific set of traits in all comparisons. In contrast to the majority of genome scans in recently diverged lineages, our data suggest that divergence landscapes in Leptidea have been shaped by directional selection and genetic drift rather than stable recombination landscapes and/or introgression.  相似文献   
79.
Mountain areas often hold special species communities, and they are high on the list of conservation concern. Global warming and changes in human land use, such as grazing pressure and afforestation, have been suggested to be major threats for biodiversity in the mountain areas, affecting species abundance and causing distribution shifts towards mountaintops. Population shifts towards poles and mountaintops have been documented in several areas, indicating that climate change is one of the key drivers of species’ distribution changes. Despite the high conservation concern, relatively little is known about the population trends of species in mountain areas due to low accessibility and difficult working conditions. Thanks to the recent improvement of bird monitoring schemes around Europe, we can here report a first account of population trends of 44 bird species from four major European mountain regions: Fennoscandia, UK upland, south‐western (Iberia) and south‐central mountains (Alps), covering 12 countries. Overall, the mountain bird species declined significantly (?7%) during 2002–2014, which is similar to the declining rate in common birds in Europe during the same period. Mountain specialists showed a significant ?10% decline in population numbers. The slope for mountain generalists was also negative, but not significantly so. The slopes of specialists and generalists did not differ from each other. Fennoscandian and Iberian populations were on average declining, while in United Kingdom and Alps, trends were nonsignificant. Temperature change or migratory behaviour was not significantly associated with regional population trends of species. Alpine habitats are highly vulnerable to climate change, and this is certainly one of the main drivers of mountain bird population trends. However, observed declines can also be partly linked with local land use practices. More efforts should be undertaken to identify the causes of decline and to increase conservation efforts for these populations.  相似文献   
80.

Background

Inorganic polyphosphate (polyP) is a fundamental and ubiquitous molecule in prokaryotes and eukaryotes. PolyP has been found in mammalian tissues with particularly high levels of long-chain polyP in bone and cartilage where critical questions remain as to its localization and function. Here, we investigated polyP presence and function in osteoblast-like SaOS-2 cells and cell-derived matrix vesicles (MVs), the initial sites of bone mineral formation.

Methods

PolyP was quantified by 4′,6-diamidino-2-phenylindole (DAPI) fluorescence and characterized by enzymatic methods coupled to urea polyacrylamide gel electrophoresis. Transmission electron microscopy and confocal microscopy were used to investigate polyP localization. A chicken embryo cartilage model was used to investigate the effect of polyP on mineralization.

Results

PolyP increased in concentration as SaOS-2 cells matured and mineralized. Particularly high levels of polyP were observed in MVs. The average length of MV polyP was determined to be longer than 196 Pi residues by gel chromatography. Electron micrographs of MVs, stained by two polyP-specific staining approaches, revealed polyP localization in the vicinity of the MV membrane. Additional extracellular polyP binds to MVs and inhibits MV-induced hydroxyapatite formation.

Conclusion

PolyP is highly enriched in matrix vesicles and can inhibit apatite formation. PolyP may be hydrolysed to phosphate for further mineralization in the extracellular matrix.

General significance

PolyP is a unique yet underappreciated macromolecule which plays a critical role in extracellular mineralization in matrix vesicles.  相似文献   
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