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951.
952.
José Marcelo Soriano Viana Mágno Sávio Ferreira Valente Fabyano Fonseca e Silva Gabriel Borges Mundim Geísa Pinheiro Paes 《Genetica》2013,141(7-9):389-399
The objective was to assess by simulation the efficacy of population structure analysis in plant breeding. Twelve populations and 300 inbred lines were simulated and genotyped using 100 microsatellite loci. The experimental material included populations with and without admixture, ancestry relationship and linkage disequilibrium, and with distinct levels of genetic differentiation and effective sizes. The analyses were performed using Structure software and employed all available models. For all the group number (K) tested, for both populations and inbred lines, the admixture model with correlated allelic frequencies provided the highest value for the logarithm of the marginal likelihood. Fitting appropriate model and using adequate sample size for individuals and markers, Structure was effective in identifying the correct population structure, migrants and individuals with genome from distinct populations. The linkage model did not result in an improvement in clustering relative to the admixture model with correlated allelic frequencies. The inclusion of prior information did not change the results; for some K values the analyses showed slight higher values of the marginal likelihood. The reduction in the number of individuals and markers negatively affected the results. There was a high variation in the most probable K value between the evaluated methods. 相似文献
953.
Viviane F. Botosso Paolo M. de A. Zanotto Mirthes Ueda Eurico Arruda Alfredo E. Gilio Sandra E. Vieira Klaus E. Stewien Teresa C. T. Peret Leda F. Jamal Maria I. de M. C. Pardini Jo?o R. R. Pinho Eduardo Massad Osvaldo A. Sant'Anna Eddie C. Holmes Edison L. Durigon and the VGDN Consortium 《PLoS pathogens》2009,5(1)
Human respiratory syncytial virus (HRSV) is the major cause of lower respiratory tract infections in children under 5 years of age and the elderly, causing annual disease outbreaks during the fall and winter. Multiple lineages of the HRSVA and HRSVB serotypes co-circulate within a single outbreak and display a strongly temporal pattern of genetic variation, with a replacement of dominant genotypes occurring during consecutive years. In the present study we utilized phylogenetic methods to detect and map sites subject to adaptive evolution in the G protein of HRSVA and HRSVB. A total of 29 and 23 amino acid sites were found to be putatively positively selected in HRSVA and HRSVB, respectively. Several of these sites defined genotypes and lineages within genotypes in both groups, and correlated well with epitopes previously described in group A. Remarkably, 18 of these positively selected tended to revert in time to a previous codon state, producing a “flip-flop” phylogenetic pattern. Such frequent evolutionary reversals in HRSV are indicative of a combination of frequent positive selection, reflecting the changing immune status of the human population, and a limited repertoire of functionally viable amino acids at specific amino acid sites. 相似文献
954.
Flavia Rodrigues da Silva Renato de Carvalho Guerreiro Henrique de Araújo Andrade Eduardo Stieler Andressa Silva 《Chronobiology international》2020,37(5):607-617
ABSTRACT
Rotating and permanent night shiftwork schedules typically result in acute and sometimes chronic sleep deprivation plus acute and sometimes chronic disruption of the circadian time structure. Immune system processes and functionalities are organized as circadian rhythms, and they are also strongly influenced by sleep status. Sleep is a vital behavioral state of living beings and a modulator of immune function and responsiveness. Shiftworkers show increased risk for developing viral infections due to possible compromise of both innate and acquired immunity responses. Short sleep and sleep loss, common consequences of shiftwork, are associated with altered integrity of the immune system. We discuss the possible excess risk for COVID-19 infection in the context of the common conditions among shiftworkers, including nurses, doctors, and first responders, among others of high exposure to the contagion, of sleep imbalance and circadian disruption. 相似文献
955.
In this work, we characterized the activities of two classes of proteases and AcP during early embryogenesis of Periplaneta americana. AcP activity was first detected at day 6 and reached a maximum level at day 10 of development. Using phosphoamino acids, phosphatase activity was shown to be directed only against phosphotyrosine at day 6 while at day 10 it was also active against phosphoserine. In parallel, two classes of proteases were detected and located within yolk granules: a clan CA-cysteine protease, which was inhibited by E-64, insensitive to CA 074 and activated by acidic pH at day 3; and a neutral serine protease, which was inhibited by aprotinin at day 6. Assays of vitellin (Vt) degradation evidenced that incubations at neutral pH induced slight proteolysis, while the incubations at acidic pH did not result in Vt degradation. However, pre-incubations of Vt with AcP increased the levels of Vt acidic proteolysis and this could be inhibited by the addition of phosphatase inhibitors. On the other hand, the same pre-incubations showed no effects on the profile of degradation at neutral pH. We propose that AcP and cysteine protease cooperate to assure Vt breakdown during early embryogenesis of P. americana. 相似文献
956.
Anderson de Sa Pinheiro Angela Ehart Nina Ebner Martina Proell Robert Schwarzenbacher Wolfgang Peti 《Biomolecular NMR assignments》2009,3(2):207-209
The resonance assignments of the human NLRP7 PYD domain have been determined based on triple-resonance experiments using uniformly
[13C,15N]-labeled protein. This assignment is the first step towards the 3D structure determination of the NLRP7 PYD domain. 相似文献
957.
Letter to the editor: Reply to Hardy & Buckley: Earliest evidence of bitumen from Homo sp. teeth is from El Sidro'n 下载免费PDF全文
Gregorio Oxilia Flavia Fiorillo Francesco Boschin Elisabetta Boaretto Salvatore A. Apicella Chiara Matteucci Daniele Panetta Rossella Pistocchi Franca Guerrini Cristiana Margherita Massimo Andretta Rita Sorrentino Giovanni Boschian Simona Arrighi Irene Dori Giuseppe Mancuso Jacopo Crezzini Alessandro Riga Maria C. Serrangeli Antonino Vazzana Piero A. Salvadori Mariangela Vandini Carlo Tozzi Adriana Moroni Robin N. M. Feeney John C. Willman Jacopo Moggi‐Cecchi Stefano Benazzi 《American journal of physical anthropology》2017,164(1):214-215
958.
959.
Ágda Nara Tavares Bandeira Maria Teresa Buril Francisco Carlos Pinheiro da Costa José Iranildo Miranda de Melo 《Nordic Journal of Botany》2017,35(1):20-24
Evolvulus flavus is a new species of Convolvulaceae found in the semiarid region of Paraíba State, Brazil. It is characterized by flowers with a yellow corolla and 4‐locular ovary. Illustrations and taxonomic notes are presented. Only four individuals of this new species have been located, resulting in its classification as ‘Endangered’ (EN) in accordance with the IUCN criteria. 相似文献
960.