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91.
Wieslander CK Rahn DD McIntire DD Acevedo JF Drewes PG Yanagisawa H Word RA 《Biology of reproduction》2009,80(3):407-414
Two mouse models of pelvic organ prolapse have been generated recently, both of which have null mutations in genes involved in elastic fiber synthesis and assembly (fibulin 5 and lysyl oxidase-like 1). Interestingly, although these mice exhibit elastinopathies early in life, pelvic organ prolapse does not develop until later in life. In this investigation we developed and validated a tool to quantify the severity of pelvic organ prolapse in mice, and we used this tool prospectively to study the role of fibulin 5, aging, and vaginal proteases in the development of pelvic organ prolapse. The results indicate that >90% of Fbln5(-/-) mice develop prolapse by 6 mo of age, even in the absence of vaginal delivery, and that increased vaginal protease activity precedes the development of prolapse. 相似文献
92.
Raquel Sobrino Pelayo Acevedo Marco A. Escudero Javier Marco Christian Gortázar 《European Journal of Wildlife Research》2009,55(2):161-165
We conducted spotlight counts from 1992 to 2006 in 59 localities to describe carnivore presence, distribution and relative
abundance in open agriculture lands in Aragon, northeastern Spain. During the study period, urban waste and carcases of domestic
livestock became less available to wild animals, and rabbit (Oryctolagus cuniculus) abundance was low after rabbit haemorragic disease. We calculated a kilometric abundance index (KAI, individuals seen per
100 km surveyed) and the ratio between the number of positive localities in which a species was detected and the total of
localities surveyed in a year. Indices to abundance and presence included: red fox (Vulpes vulpes), KAI per 100 km 10.70 and 100.0% localities per year; stray dog (Canis familiaris), KAI 0.48 and 22.6% localities; wildcat (Felis silvestris), KAI 0.10 and 19.1% localities; domestic cat (Felis catus), KAI 0.21 and 20.6% localities; polecat (Mustela putorius), KAI 0.02 and 2.0% localities; badger (Meles meles), KAI 0.16 and 23.6% localities; stone marten (Martes foina), KAI 0.11 and 19.6% localities; weasel (Mustela nivalis), KAI 0.002 and 0.6% localities; and genet (Genetta genetta), KAI 0.06 and 10.0% localities. Indices of badger abundance increased significantly, whereas indices of stray dogs decreased
significantly over the study period. Abundance indices of red fox, the most important predator of small game, were stable
throughout the study period. No significant trend was observed to other studied species. This study concludes that Aragon
region maintains a diverse and rather stable carnivore community and shows that large scale data may help to identify trends
of the more abundant wild and feral carnivores. 相似文献
93.
Marlen Castellanos Zurina Cinza Zaily Dorta Gloria Veliz Héctor Vega Irma Lorenzo Sergio Ojeda Santiago Dueñas‐Carrera Liz Alvarez‐Lajonchere Gillian Martínez Elena Ferrer Miladys Limonta Marbelis Linares Odalis Ruiz Boris Acevedo Dinorah Torres Gabriel Márquez Luis Herrera Enrique Arús 《The journal of gene medicine》2010,12(1):107-116
94.
Carolina Mascayano Gabriel Núñez Waldo Acevedo Marcos Caroli Rezende 《Journal of molecular modeling》2010,16(5):1039-1045
The lipoxygenases (LOX) are a family of non-heme iron-containing dioxygenases which catalyze the stereospecific insertion
of molecular oxygen into arachidonic acid, leading to hydroxy derivatives as end products. In this work, we docked arachidonic
acid and two of its competitive inhibitors, flavonoids baicalein and quercetin, into the binding pockets of human 12- and
15-lipoxygenase. Steered molecular dynamics (SMD) simulations were employed to study the unbinding processes of the substrate
and inhibitors from the two isoforms. 相似文献
95.
96.
McCartney MA Acevedo J Heredia C Rico C Quenoville B Bermingham E McMillan WO 《Molecular ecology》2003,12(11):2963-2973
We used molecular approaches to study the status of speciation in coral reef fishes known as hamlets (Serranidae: Hypoplectrus). Several hamlet morphospecies coexist on Caribbean reefs, and mate assortatively with respect to their strikingly distinct colour patterns. We provide evidence that, genetically, the hamlets display characteristics common in species flocks on land and in freshwaters. Substitutions within two mitochondrial DNA (mtDNA) protein-coding genes place hamlets within a monophyletic group relative to members of two related genera (Serranus and Diplectrum), and establish that the hamlet radiation must have been very recent. mtDNA distances separating hamlet morphospecies were slight (0.6 +/- 0.04%), yielding a coalescent estimate for the age of the hamlet flock of approximately 430 000 years. Morphospecies did not sort into distinct mtDNA haplotype phylogroups, and alleles at five hypervariable microsatellite loci were shared broadly across species boundaries. None the less, molecular variation was not distributed at random. Analyses of mtDNA haplotype frequencies and nested clades in haplotype networks revealed significant genetic differences between geographical regions and among colour morphospecies. We also observed significant microsatellite differentiation between geographical regions and in Puerto Rico, among colour morphospecies; the latter providing evidence for reproductive isolation between colour morphospecies at this locale. In our Panama collection, however, colour morphospecies were mostly genetically indistinguishable. This mosaic pattern of DNA differentiation implies a complex interaction between population history, mating behaviour and geography and suggests that porous boundaries separate species in this flock of brilliantly coloured coral reef fishes. 相似文献
97.
Wild potato species have a gametophytic self-incompatibility system controlled by a single multiallelic S locus. In the style, the S-RNase gene codes for an allele-specific ribonuclease that is involved in the rejection of pollen that carries the same S haplotype. This gene has 5 conserved regions (C1-C5) and highly variable regions outside of these areas that play a role in S-RNase allele specificity. In this work, PCR-mediated amplification of genomic DNA from 2 Solanum chacoense accessions was performed using primers designed on the basis of the C1 and C4 conserved regions. By sequencing the PCR products, a new S-RNase allele (S16) was identified in 1 plant of the QBCM argentinian accession. Comparison of the partial sequence (from C2 to C3) of S16 RNase with those of 11 S-RNase genes of other Solanaceae species showed the highest and the lowest similarity scores within the same plant species (respectively, 71% with the S11 and S13 RNase and 35% with the S2 RNase). Differences at the nucleotide level between S16 and S11 RNase alleles are discussed. 相似文献
98.
Experimental vaccine protection against homologous and heterologous strains of feline immunodeficiency virus. 总被引:14,自引:9,他引:5
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J K Yamamoto T Hohdatsu R A Olmsted R Pu H Louie H A Zochlinski V Acevedo H M Johnson G A Soulds M B Gardner 《Journal of virology》1993,67(1):601-605
More than 90% of cats immunized with inactivated whole infected-cell or cell-free feline immunodeficiency virus (FIV) vaccines were protected against intraperitoneal infection with 10 50% animal infectious doses of either homologous FIV Petaluma (28 of 30 cats) or heterologous FIV Dixon strain (27 of 28 cats). All 15 control cats were readily infected with either strain of FIV. Protection appears to correlate with antiviral envelope antibody levels by a mechanism yet to be determined. 相似文献
99.
The stereospecific d-glucose transport activity of cholate extracts from human erythrocyte membranes
The glucose transport protein of human erythrocyte membranes was solubilized with cholate to facilitate rapid reconstitution and direct glucose transport measurements. This may simplify the isolation of the native glucose transporter. In most experiments the membranes were prepared from fresh blood within 8 h, frozen in liquid nitrogen and stored at ?70°C to minimize proteolytic degradation. Solubilization with 25 mM cholate in the presence of 200 mM NaCl at pH 8.4 for 12 min at room temperature gave a high d-glucose transport activity. The solubilized mixture contained 20% of the total membrane protein, only 6% of the polypeptides of molecular weight around 90 000, 23% of the polypeptides of molecular weight around 55 000, 30% of the phospholipids and at least 6% of the stereospecific d-glucose transport activity. At cholate concentrations up to 22 mM the ratio of solubilized phospholipids to cholate increased steeply, concomitant with an increase in solubilized activity. Above 30 mM cholate the activity diminished. At 4°C the activity of the extrac decreased rapidly within the first day and slowly during the next few days. The initial changes seem to have produced a fairly stable, but not native form or fragment of the transporter. When 20 mM EDTA and 5 mM dithioerythritol were included in the solubilization mixture a high activity was preserved for about one day. 相似文献
100.
Effects of antihypertensive treatment on cardiac IGF-1 during prevention of ventricular hypertrophy in the rat. 总被引:4,自引:0,他引:4
J E Jalil R Ebensperger J Meléndez E Acevedo M Sapag-Hagar F González-Jara A Gálvez V Pérez-Montes S Lavandero 《Life sciences》1999,64(18):1603-1612
There is some evidence that cardiac rather than circulating insulin-like growth factor-1 (IGF-1) levels contribute to the development of renovascular hypertensive left ventricular hypertrophy (LVH), remaining unknown the effects of antihypertensive drugs on IGF-1 levels. We have assessed here the preventive effects of enalapril, losartan, propanolol and alpha-methyldopa on left ventricle (LV) and circulating IGF-1 levels in a rat model of hypertension and LVH (Goldblatt, GB). Our results show that relative LV mass and the LV content of IGF-1 were significantly lower with all antihypertensive drugs in GB rats (p<0.001). Serum concentrations of IGF-1 were lower in GB rats treated with enalapril, alpha-methyldopa and propanolol (p<0.01), but not in those treated with losartan. These results support the hypothesis that local rather than seric IGF-1 contributes to the development of left ventricular hypertrophy induced by pressure overload in the rat. 相似文献