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91.
Mammalian protein-protein interaction trap (MAPPIT) analysis of STAT5, CIS, and SOCS2 interactions with the growth hormone receptor 总被引:1,自引:0,他引:1
92.
We evaluated the effects of Leishmania spp infection on several
population parameters of Lutzomyia longipalpis sensu lato
andLutzomyia pseudolongipalpis, vectors of visceral leishmaniasis
in Venezuela, under experimental conditions during the first post-feeding period.
Females of both species were allowed to feed and engorge on a suspension of fresh
washed human red blood cells in foetal calf serum. These blood cells were either
non-infected or infected with one of the fourLeishmania spp strains
and were offered through a chicken skin membrane. The longevity, life expectancy and
the fecundity of uninfected flies were similar in both species, but the fertility was
significantly lower in uninfected Lu. longipalpis females. In all
cases, the infection of Lu. longipalpis and Lu.
pseudolongipalpis by the Leishmania strains resulted in
significant detrimental effects, which exerted a fitness cost expressed by reduced
survival and life expectancy, as well as decreased fertility and fecundity compared
with the control groups. Nevertheless, differences in these parameters were observed
between these vector species depending on whether they were infected with the
autochthonous Venezuelan Leishmania infantum strain (NESA) or the
Brazilian reference strain (PP75). The experimental data obtained agree with field
data on the natural infection of these vector species and the significance of this
scenario is discussed. 相似文献
93.
94.
95.
Determining meteorological drivers of salt marsh mosquito peaks in tropical northern Australia 下载免费PDF全文
Susan P. Jacups Jane Carter Nina Kurucz Joseph McDonnell Peter I. Whelan 《Journal of vector ecology》2015,40(2):277-281
In northern Australia the northern salt marsh mosquito Aedes vigilax is a vector of Ross River virus and is an appreciable pest. A coastal wetland adjacent to Darwin's residential suburbs offers a favorable habitat for Ae. vigilax, and despite vigilant mosquito control efforts, peaks of Ae. vigilax occur in excess of 500/trap/night some months. To improve mosquito control for disease and nuisance biting to nearby residential areas, we sought to investigate meteorological drivers associated with these Ae. vigilax peaks. We fitted a cross‐sectional logistic regression model to weekly counts of female Ae. vigilax mosquitoes collected between July, 1998 and June, 2009 against variables, tide, rainfall, month, year, and larval control. Aedes vigilax peaks were associated with rainfall during the months September to November compared with January, when adjusted for larval control and tide. To maximize mosquito control efficiency, larval control should continue to be implemented after high tides and with increased emphasis on extensive larval hatches triggered by rainfall between September and November each year. This study reiterates the importance of monitoring and evaluating service delivery programs. Using statistical modelling, service providers can obtain solutions to operational problems using routinely collected data. These methods may be applicable in mosquito surveillance or control programs in other areas. 相似文献
96.
The freshwater genus Hyalella Smith, 1874 has a distribution restricted to the Western Hemisphere with most species being found in South America. In this report we describe a new species of Hyalella from the Atlantic Forest of the Misiones province, Argentina. 相似文献
97.
Schalk-Hihi C Schubert C Alexander R Bayoumy S Clemente JC Deckman I DesJarlais RL Dzordzorme KC Flores CM Grasberger B Kranz JK Lewandowski F Liu L Ma H Maguire D Macielag MJ McDonnell ME Mezzasalma Haarlander T Miller R Milligan C Reynolds C Kuo LC 《Protein science : a publication of the Protein Society》2011,20(4):670-683
A high-resolution structure of a ligand-bound, soluble form of human monoglyceride lipase (MGL) is presented. The structure highlights a novel conformation of the regulatory lid-domain present in the lipase family as well as the binding mode of a pharmaceutically relevant reversible inhibitor. Analysis of the structure lacking the inhibitor indicates that the closed conformation can accommodate the native substrate 2-arachidonoyl glycerol. A model is proposed in which MGL undergoes conformational and electrostatic changes during the catalytic cycle ultimately resulting in its dissociation from the membrane upon completion of the cycle. In addition, the study outlines a successful approach to transform membrane associated proteins, which tend to aggregate upon purification, into a monomeric and soluble form. 相似文献
98.
Background
The aqueous humor (AH), a liquid of the anterior and posterior chamber of the eye, comprises many proteins with various roles and important biological functions. Many of these proteins have not been identified yet and their functions in AH are still unknown. Recently, our laboratory published the protein database of AH obtained from healthy rabbits which expanded known protein identifications by 65%. Our present study extends our previous work and analyses AH following two types of cataract surgery incision procedures (clear corneal and limbal incisions) by using two dimensional gel electrophoresis (2-DE) and liquid chromatography tandem mass spectrometry (LC-MS/MS). Although both incision protocols are commonly used during cataract surgeries, the difference in protein composition and their release into AH following each surgery has never been systematically compared and remains unclear. The first step, which is the focus of this work, is to assess the scale of the protein change, at which time does maximum release occurs and when possible, to identify protein changes. 相似文献99.
Pivac N Knezević A Gornik O Pucić M Igl W Peeters H Crepel A Steyaert J Novokmet M Redzić I Nikolac M Hercigonja VN Curković KD Curković M Nedić G Muck-Seler D Borovecki F Rudan I Lauc G 《Molecular & cellular proteomics : MCP》2011,10(1):M110.004200
Over a half of all proteins are glycosylated, and their proper glycosylation is essential for normal function. Unfortunately, because of structural complexity of nonlinear branched glycans and the absence of genetic template for their synthesis, the knowledge about glycans is lagging significantly behind the knowledge about proteins or DNA. Using a recently developed quantitative high throughput glycan analysis method we quantified components of the plasma N-glycome in 99 children with attention-deficit hyperactivity disorder (ADHD), 81 child and 5 adults with autism spectrum disorder, and a total of 340 matching healthy controls. No changes in plasma glycome were found to associate with autism spectrum disorder, but several highly significant associations were observed with ADHD. Further structural analysis of plasma glycans revealed that ADHD is associated with increased antennary fucosylation of biantennary glycans and decreased levels of some complex glycans with three or four antennas. The design of this study prevented any functional conclusions about the observed associations, but specific differences in glycosylation appears to be strongly associated with ADHD and warrants further studies in this direction. 相似文献
100.
Richard P. Duncan Richard T. Corlett Amy K. Hahs Michael A. McCarthy Mark J. McDonnell Mark W. Schwartz Ken Thompson Peter A. Vesk Nicholas S. G. Williams 《Global Ecology and Biogeography》2011,20(4):509-519
Aim Urban environments around the world share many features in common, including the local extinction of native plant species. We tested the hypothesis that similarity in environmental conditions among urban areas should select for plant species with a particular suite of traits suited to those conditions, and lead to the selective extinction of species lacking those traits. Location Eleven cities with data on the plant species that persisted and those that went locally extinct within at least the last 100 years following urbanization. Methods We compiled data on 11 plant traits for 8269 native species in the 11 cities and used hierarchical logistic regression models to identify the degree to which traits could distinguish species that persisted from those that went locally extinct in each city. The trait effects from each city were then combined in a meta‐analysis. Results The cities fell into two groups: those with relatively low rates of extinction (less than 0.05% species per year – Adelaide, Hong Kong, Los Angeles, San Diego and San Francisco), for which no traits reliably predicted the pattern of extinction, and those with higher rates of extinction (> 0.08% species per year – Auckland, Chicago, Melbourne, New York, Singapore and Worcester, MA), where short‐statured, small‐seeded plants were more likely to go extinct. Main conclusions Our analysis reveals patterns in trait selectivity consistent with local studies, suggesting some consistency in trait selection by urbanization. Overall, however, few traits reliably predicted the pattern of plant extinction across cities, making it difficult to identify a priori the extinction‐prone species most likely to be affected by urban expansion. 相似文献