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31.
32.
Lovis C Mayor M Pepe F Alibert Y Benz W Bouchy F Correia AC Laskar J Mordasini C Queloz D Santos NC Udry S Bertaux JL Sivan JP 《Nature》2006,441(7091):305-309
Over the past two years, the search for low-mass extrasolar planets has led to the detection of seven so-called 'hot Neptunes' or 'super-Earths' around Sun-like stars. These planets have masses 5-20 times larger than the Earth and are mainly found on close-in orbits with periods of 2-15 days. Here we report a system of three Neptune-mass planets with periods of 8.67, 31.6 and 197 days, orbiting the nearby star HD 69830. This star was already known to show an infrared excess possibly caused by an asteroid belt within 1 au (the Sun-Earth distance). Simulations show that the system is in a dynamically stable configuration. Theoretical calculations favour a mainly rocky composition for both inner planets, while the outer planet probably has a significant gaseous envelope surrounding its rocky/icy core; the outer planet orbits within the habitable zone of this star. 相似文献
33.
Sara Canato João D. Santos Ana S. Carvalho Kerman Aloria Margarida D. Amaral Rune Matthiesen André O. Falcao Carlos M. Farinha 《Cellular and molecular life sciences : CMLS》2018,75(24):4495-4509
Misfolded F508del-CFTR, the main molecular cause of the recessive disorder cystic fibrosis, is recognized by the endoplasmic reticulum (ER) quality control (ERQC) resulting in its retention and early degradation. The ERQC mechanisms rely mainly on molecular chaperones and on sorting motifs, whose presence and exposure determine CFTR retention or exit through the secretory pathway. Arginine-framed tripeptides (AFTs) are ER retention motifs shown to modulate CFTR retention. However, the interactions and regulatory pathways involved in this process are still largely unknown. Here, we used proteomic interaction profiling and global bioinformatic analysis to identify factors that interact differentially with F508del-CFTR and F508del-CFTR without AFTs (F508del-4RK-CFTR) as putative regulators of this specific ERQC checkpoint. Using LC–MS/MS, we identified kinesin family member C1 (KIFC1) as a stronger interactor with F508del-CFTR versus F508del-4RK-CFTR. We further validated this interaction showing that decreasing KIFC1 levels or activity stabilizes the immature form of F508del-CFTR by reducing its degradation. We conclude that the current approach is able to identify novel putative therapeutic targets that can be ultimately used to the benefit of CF patients. 相似文献
34.
Maíra Xavier Araújo Claudiney Biral Dos Santos Freddy Bravo Claudio J.B. de Carvalho 《Journal of Natural History》2017,51(29-30):1713-1725
Septemtrichomyia Bravo is a subgenus of Trichomyia Haliday in Curtis that includes 14 Neotropical species. Here we describe four new species of moth flies from the state of Espírito Santo in Brazil: Trichomyia capixaba sp. nov., T. gabia sp. nov., T. gustavoi sp. nov. and T. menezesi sp. nov. We also provide an updated key to males of the subgenus Septemtrichomyia.
www.zoobank.org/urn:lsid:zoobank.org:pub:4E3C2133-2FCD-4A14-B9A3-A55715931AB4 相似文献
35.
Paulo Mateus Martins-Sobrinho Winny Gomes de Oliveira Silva Elizandra Gomes dos Santos Geraldo Jorge Barbosa de Moura Jaqueline Bianque de Oliveira 《Journal of Natural History》2017,51(27-28):1639-1648
Despite the fact that Brazil is the most-studied country regarding helminths of amphibians, only around 8% of Brazilian anurans have had at least one study made of their helminth fauna. Therefore, the aim of this study was to describe the helminth community of nine species of Atlantic Rainforest anurans of two different families, eight of them with no previous study, and six of which are endemic to Brazil. The analysed hosts for their parasites were: Dendropsophus minutus (n = 48), Scinax auratus (n = 36), D. branneri (n = 33), D. elegans (n = 26), Hypsiboas albomarginatus (n = 22), Pithecopus nordestinus (n = 19), D. decipiens (n = 12), D. haddadi (n = 11) and S. x-signatus (n = 11). A total of 781 helminths were collected from 106 (48.6%) of 218 analysed hosts, 656 Centrorhyncus sp. cystacanths and 125 nematodes: 76 adults (25 Cosmocerca sp.; three Cosmocerceidae gen. sp.; 20 Cosmocerca parva, 20 Cosmocercella phyllomedusae, five Aplectana sp., two Oswaldocruzia sp. and one Rhabdias sp.), 43 encysted larvae (nine Porrocaecum sp. and 34 Brevimulticaecum sp.) and six Physaloptera sp. larvae. Anurans may display many roles within the helminth life cycles, as they act as both predator and prey to a wide variety of animals. Consequently, we have found helminths that use anurans as definitive, intermediate and paratenic hosts. Opposing other surveys in which nematodes are the most prevalent and abundant parasites, acanthocephalans were the most prevalent taxa. These findings highlight the lack of knowledge regarding the helminth fauna of anurans and reveal many gaps with respect to their infection patterns in amphibians. 相似文献
36.
The error threshold for replication, the critical copying fidelity below which the fittest genotype deterministically disappears, limits the length of the genome that can be maintained by selection. Primordial replication must have been error-prone, and so early replicators are thought to have been necessarily short. The error threshold also depends on the fitness landscape. In an RNA world, many neutral and compensatory mutations can raise the threshold, below which the functional phenotype, rather than a particular sequence, is still present. Here we show, on the basis of comparative analysis of two extensively mutagenized ribozymes, that with a copying fidelity of 0.999 per digit per replication the phenotypic error threshold rises well above 7,000 nucleotides, which permits the selective maintenance of a functionally rich riboorganism with a genome of more than 100 different genes, the size of a tRNA. This requires an order of magnitude of improvement in the accuracy of in vitro-generated polymerase ribozymes. Incidentally, this genome size coincides with that estimated for a minimal cell achieved by top-down analysis, omitting the genes dealing with translation. 相似文献
37.
Li B Boast S de los Santos K Schieren I Quiroz M Teitelbaum SL Tondravi MM Goff SP 《Nature genetics》2000,24(3):304-308
The c-Abl protein is a non-receptor tyrosine kinase involved in many aspects of mammalian development. c-Abl kinase is widely expressed, but high levels are found in hyaline cartilage in the adult, bone tissue in newborn mice, and osteoblasts and associated neovasculature at sites of endochondrial ossification in the fetus. Mice homozygous for mutations in the gene encoding c-Abl (AIM) display increased perinatal mortality, reduced fertility, foreshortened crania and defects in the maturation of B cells in bone marrow. Here we demonstrate that Abl-/- mice are also osteoporotic. The long bones of mutant mice contain thinner cortical bone and reduced trabecular bone volume. The osteoporotic phenotype is not due to accelerated bone turnover--both the number and activity of osteoclasts are similar to those of control littermates--but rather to dysfunctional osteoblasts. In addition, the rate of mineral apposition in the mutant animals is reduced. Osteoblasts from both stromal and calvarial explants showed delayed maturation in vitro as measured by expression of alkaline phosphatase (ALP), induction of mRNA encoding osteocalcin and mineral deposition. 相似文献
38.
M. A. Rossi A. L. Ferreira S. M. Paiva J. C. M. Santos 《Cellular and molecular life sciences : CMLS》1973,29(10):1272-1274
Zusammenfassung Elektronenoptischer Nachweis, dass Skorpiongift (Tityus serrulatus) nach i.p. Verabreichung an der quergestreiften Muskulatur der Küchenschabe eine starke nekrosierende Wirkung ausübt. 相似文献
39.
A. C. Santos M. T. Chua N. Eufemio C. Abela 《Cellular and molecular life sciences : CMLS》1970,26(10):1053-1054
Zusammenfassung Aus den zerkleinerten Blättern vonCyanotis vaga (Commelinaceae) wurde durch Benzolextraktion und Chromatographie mit Silikagel eine neue Substanz isoliert: C27H44O7 (Sp. 146–151), die nach den spektrometrischen Daten (IR, NMR, UV, MS) mit dem Insektenhormon Ecdysteron stereoisomer ist.
Dedicated to Prof. Dr. R. Tschesche, Organisch-Chemisches Institut, Universität Bonn (Germany) on the occasion of his 65th birthday, for the invaluable help and inspiration he has given us. 相似文献
Dedicated to Prof. Dr. R. Tschesche, Organisch-Chemisches Institut, Universität Bonn (Germany) on the occasion of his 65th birthday, for the invaluable help and inspiration he has given us. 相似文献
40.