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151.
David S. Goodsell Christine Zardecki Luigi Di Costanzo Jose M. Duarte Brian P. Hudson Irina Persikova Joan Segura Chenghua Shao Maria Voigt John D. Westbrook Jasmine Y. Young Stephen K. Burley 《Protein science : a publication of the Protein Society》2020,29(1):52-65
Analyses of publicly available structural data reveal interesting insights into the impact of the three‐dimensional (3D) structures of protein targets important for discovery of new drugs (e.g., G‐protein‐coupled receptors, voltage‐gated ion channels, ligand‐gated ion channels, transporters, and E3 ubiquitin ligases). The Protein Data Bank (PDB) archive currently holds > 155,000 atomic‐level 3D structures of biomolecules experimentally determined using crystallography, nuclear magnetic resonance spectroscopy, and electron microscopy. The PDB was established in 1971 as the first open‐access, digital‐data resource in biology, and is now managed by the Worldwide PDB partnership (wwPDB; wwPDB.org ). US PDB operations are the responsibility of the Research Collaboratory for Structural Bioinformatics PDB (RCSB PDB). The RCSB PDB serves millions of RCSB.org users worldwide by delivering PDB data integrated with ~40 external biodata resources, providing rich structural views of fundamental biology, biomedicine, and energy sciences. Recently published work showed that the PDB archival holdings facilitated discovery of ~90% of the 210 new drugs approved by the US Food and Drug Administration 2010–2016. We review user‐driven development of RCSB PDB services, examine growth of the PDB archive in terms of size and complexity, and present examples and opportunities for structure‐guided drug discovery for challenging targets (e.g., integral membrane proteins). 相似文献
152.
Fuente David Lazar Dusan Oliver-Villanueva Jose Vicente Urchueguía Javier F. 《Photosynthesis research》2021,147(1):75-90
Photosynthesis Research - In this work, we reconstructed the absorption spectrum of different Synechocystis sp. PCC 6803 optical strains by summing the computed signature of all pigments present in... 相似文献
153.
Morales-Gamba Ruben Dario de Araújo Maria Lúcia Góes Barcellos Jose Fernando Marcon Jaydione Luiz 《Environmental Biology of Fishes》2021,104(12):1665-1672
Environmental Biology of Fishes - This study evaluated how the plasma steroid hormones testosterone (T) and 17β-estradiol (E2) are related to follicular development in regenerating females of... 相似文献
154.
Jose Luis Martinez-Sande Javier Garcia-Seara Laila Gonzalez-Melchor Moises Rodriguez-Mañero Aurora Baluja Xesus Alberte Fernandez-Lopez Jose Ramon Gonzalez Juanatey 《Indian pacing and electrophysiology journal》2021,21(2):89-94
PurposeDespite the developments in conventional transvenous pacemakers (VVI-PM), the procedure is still associated with significant complications. Although there are no prospective clinical trials that compared VVI-PM with transcatheter pacemaker systems (TPS).MethodsThis is a prospective, observational, single-center study that included all patients with an indication for a single-chamber pacemaker implant within a 4-year period. All clinical, ECG and echocardiographic characteristics at implant, electrical parameters, associated complications and mortality were analyzed. A Cox survival model and a Bayesian cohort analysis were performed for differences in complication rates between groups.ResultsThere were 443 patients included (198 TPS and 245 VVI-PM). The mean age was 81.5 years (TPS group, 79.2 ± 6.6 years; VVI-PM group, 83.5 ± 8.9 years). There was a male predominance in TPS group (123, 62.1% vs. 67, 27.3%; p < 0.001). The presence of systolic dysfunction and renal insufficiency were more frequent in VVI-PM group than in TPS patients. Mean follow-up was 22.3 ± 15.9 months. In a multivariable paired data the TPS group presented fewer complications than VVI-PM group (HR = 0.39 [0.15–0.98], p-value 0.013), but major complications were not different (6, 3% vs 14, 5.6% respectively, p = 0.1761). There was no difference in the mortality rate between the groups. The TPS group had less risk than VVI-PM group to have a complication, with a 96% of probability.ConclusionsTPS patients had a lower overall complication rate than VVI-PM patients including matched-pair samples using a Bayesian analysis. These results confirm the safety profile of TPS in clinical practice. 相似文献
155.
156.
Jose Tavera 《Journal of fish biology》2021,99(3):888-895
The genus Chaenopsis presently includes 10 species, four in the eastern Pacific and six in the western Atlantic. Five individuals of an undescribed species of this genus were obtained at Gorgona Island in the eastern Pacific of Colombia, in depths between 3 and 5 m. This new species differs from all the Eastern Pacific species in an array of traits including meristic, coloration and morphometric characters. Chaenopsis celeste new species differs from its only sympatric species, C. deltarrhis, in having fewer pectoral rays, fewer dorsal spines and more dorsal-fin soft rays and anal-fin elements. This new species is found over shallow sandy, rubble and small rocks bottoms from Costa Rica to Colombia. 相似文献
157.
158.
Beatriz Mello Qiqing Tao Jose Barba‐Montoya Sudhir Kumar 《Molecular ecology resources》2021,21(1):122-136
Simultaneous molecular dating of population and species divergences is essential in many biological investigations, including phylogeography, phylodynamics and species delimitation studies. In these investigations, multiple sequence alignments consist of both intra‐ and interspecies samples (mixed samples). As a result, the phylogenetic trees contain interspecies, interpopulation and within‐population divergences. Bayesian relaxed clock methods are often employed in these analyses, but they assume the same tree prior for both inter‐ and intraspecies branching processes and require specification of a clock model for branch rates (independent vs. autocorrelated rates models). We evaluated the impact of a single tree prior on Bayesian divergence time estimates by analysing computer‐simulated data sets. We also examined the effect of the assumption of independence of evolutionary rate variation among branches when the branch rates are autocorrelated. Bayesian approach with coalescent tree priors generally produced excellent molecular dates and highest posterior densities with high coverage probabilities. We also evaluated the performance of a non‐Bayesian method, RelTime, which does not require the specification of a tree prior or a clock model. RelTime's performance was similar to that of the Bayesian approach, suggesting that it is also suitable to analyse data sets containing both populations and species variation when its computational efficiency is needed. 相似文献
159.
Mª Dolores Ramos-Barbero Tomeu Viver Ane Zabaleta Ece Senel María Gomariz Iñaki Antigüedad Fernando Santos Manuel Martínez-García Ramon Rosselló-Móra Josefa Antón 《Environmental microbiology》2021,23(7):3477-3498
Microbial communities in hypersaline underground waters derive from ancient organisms trapped within the evaporitic salt crystals and are part of the poorly known subterranean biosphere. Here, we characterized the viral and prokaryotic assemblages present in the hypersaline springs that dissolve Triassic-Keuper evaporite rocks and feed the Añana Salt Valley (Araba/Alava, Basque Country, Spain). Four underground water samples (around 23% total salinity) with different levels of exposure to the open air were analysed by means of microscopy and metagenomics. Cells and viruses in the spring water had lower concentrations than what are normally found in hypersaline environments and seemed to be mostly inactive. Upon exposure to the open air, there was an increase in activity of both cells and viruses as well as a selection of phylotypes. The underground water was inhabited by a rich community harbouring a diverse set of genes coding for retinal binding proteins. A total of 35 viral contigs from 15 to 104 kb, representing partial or total viral genomes, were assembled and their evolutionary changes through the spring system were followed by SNP analysis and metagenomic island tracking. Overall, both the viral and the prokaryotic assemblages changed quickly upon exposure to the open air conditions. 相似文献
160.