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991.
992.
Chevalier V Rakotondrafara T Jourdan M Heraud JM Andriamanivo HR Durand B Ravaomanana J Rollin PE Rakotondravao R 《PLoS neglected tropical diseases》2011,5(12):e1423
Rift Valley fever is an acute, zoonotic viral disease of domestic ruminants, caused by a phlebovirus (Bunyaviridae family). A large outbreak occurred in Madagascar in 2008-2009. The goal of the present study was to evaluate the point prevalence of antibodies against Rift Valley Fever Virus (RVFV) in cattle in the Anjozorobe district, located in the wet and temperate highland region of Madagascar and yet heavily affected by the disease, and analyse environmental and trade factors potentially linked to RVFV transmission. A serological study was performed in 2009 in 894 bovines. For each bovine, the following variables were recorded: age, location of the night pen, minimum distance from the pen to the nearest water point and the forest, nearest water point type, and herd replacement practices. The serological data were analyzed using a generalized linear mixed model. The overall anti-RVFV IgG seroprevalence rate was 28% [CI95% 25-31]. Age was statistically linked to prevalence (p = 10(-4)), being consistent with a recurrent RVFV circulation. Distance from the night pen to the nearest water point was a protective factor (p = 5.10(-3)), which would be compatible with a substantial part of the virus transmission being carried out by nocturnal mosquito vectors. However, water point type did not influence the risk of infection: several mosquito species are probably involved. Cattle belonging to owners who purchase animals to renew the herd were significantly more likely to have seroconverted than others (p = 0.04): cattle trade may contribute to the introduction of the virus in this area. The minimum distance of the night pen to the forest was not linked to the prevalence. This is the first evidence of a recurrent transmission of RVFV in such an ecosystem that associates a wet, temperate climate, high altitude, paddy fields, and vicinity to a dense rain forest. Persistence mechanisms need to be further investigated. 相似文献
993.
Maria de Jesus B. Cavalcante Jacques Escoute Jean Paul Madeira Rocio E. Romero Michel R. Nicole Luis C. Oliveira Chantal Hamelin Marc Lartaud Jean L. Verdeil 《Tropical plant biology》2011,4(2):134-143
Globally, the banana plant (Musa spp) is the fourth most important crop after rice, wheat and corn (based on production in tons). It is cultivated in more than 100 tropical and subtropical countries, mainly by small producers and is a fundamental food source for millions of people. Black leaf streak disease (BLSD), caused by Mycosphaerella fijiensis Morelet (sexual phase) or Paracercospora fijiensis (Morelet) Deighton (asexual phase), is the main disease affecting the world??s banana culture. This disease has a wide geographical distribution accounting for losses exceeding 50% of global banana production. We conducted a comparative histocytological study on the kinetics of the infection process using three banana genotypes with phenotypes that differ in resistance to BLSD: Grand Naine (Susceptible), Pisang Madu (Partially Resistant) and Calcutta 4 (Resistant). Experiments were conducted under controlled conditions with the objective of characterizing the cellular interaction processes between M. fijiensis and Musa acuminata. Conidia germination occurred 24 hours after inoculation. Germination rates were high (97%) and there were no significant differences between the three genotypes (P?>?0.147). The Peroxidase enzyme and H2O2 were associated with a hypersensitivity-like reaction in the resistant genotype Calcutta 4, indicating a possible role of the enzyme or its product as defense mechanisms against M. fijiensis in banana plants. 相似文献
994.
Timpson P McGhee EJ Erami Z Nobis M Quinn JA Edward M Anderson KI 《Journal of visualized experiments : JoVE》2011,(56):e3089
Cell migration is fundamental to many aspects of biology, including development, wound healing, the cellular responses of the immune system, and metastasis of tumor cells. Migration has been studied on glass coverslips in order to make cellular dynamics amenable to investigation by light microscopy. However, it has become clear that many aspects of cell migration depend on features of the local environment including its elasticity, protein composition, and pore size, which are not faithfully represented by rigid two dimensional substrates such as glass and plastic. Furthermore, interaction with other cell types, including stromal fibroblasts and immune cells, has been shown to play a critical role in promoting the invasion of cancer cells. Investigation at the molecular level has increasingly shown that molecular dynamics, including response to drug treatment, of identical cells are significantly different when compared in vitro and in vivo. Ideally, it would be best to study cell migration in its naturally occurring context in living organisms, however this is not always possible. Intermediate tissue culture systems, such as cell derived matrix, matrigel, organotypic culture (described here) tissue explants, organoids, and xenografts, are therefore important experimental intermediates. These systems approximate certain aspects of an in vivo environment but are more amenable to experimental manipulation such as use of stably transfected cell lines, drug treatment regimes, long term and high-resolution imaging. Such intermediate systems are especially useful as proving grounds to validate probes and establish parameters required to image the dynamic response of cells and fluorescent reporters prior to undertaking imaging in vivo. As such, they can serve an important role in reducing the need for experiments on living animals. 相似文献
995.
Molecular Ecology Resources Primer Development Consortium Agata K Alasaad S Almeida-Val VM Alvarez-Dios JA Barbisan F Beadell JS Beltrán JF Benítez M Bino G Bleay C Bloor P Bohlmann J Booth W Boscari E Caccone A Campos T Carvalho BM Climaco GT Clobert J Congiu L Cowger C Dias G Doadrio I Farias IP Ferrand N Freitas PD Fusco G Galetti PM Gallardo-Escárate C Gaunt MW Ocampo ZG Gonçalves H Gonzalez EG Haye P Honnay O Hyseni C Jacquemyn H Jowers MJ Kakezawa A Kawaguchi E Keeling CI Kwan YS 《Molecular ecology resources》2011,11(3):586-589
This article documents the addition of 238 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Alytes dickhilleni, Arapaima gigas, Austropotamobius italicus, Blumeria graminis f. sp. tritici, Cobitis lutheri, Dendroctonus ponderosae, Glossina morsitans morsitans, Haplophilus subterraneus, Kirengeshoma palmata, Lysimachia japonica, Macrolophus pygmaeus, Microtus cabrerae, Mytilus galloprovincialis, Pallisentis (Neosentis) celatus, Pulmonaria officinalis, Salminus franciscanus, Thais chocolata and Zootoca vivipara. These loci were cross-tested on the following species: Acanthina monodon, Alytes cisternasii, Alytes maurus, Alytes muletensis, Alytes obstetricans almogavarii, Alytes obstetricans boscai, Alytes obstetricans obstetricans, Alytes obstetricans pertinax, Cambarellus montezumae, Cambarellus zempoalensis, Chorus giganteus, Cobitis tetralineata, Glossina fuscipes fuscipes, Glossina pallidipes, Lysimachia japonica var. japonica, Lysimachia japonica var. minutissima, Orconectes virilis, Pacifastacus leniusculus, Procambarus clarkii, Salminus brasiliensis and Salminus hilarii. 相似文献
996.
Durand TC Sergeant K Renaut J Planchon S Hoffmann L Carpin S Label P Morabito D Hausman JF 《Journal of Proteomics》2011,74(8):1396-1410
The forest ecosystem is of particular importance from an economic and ecological perspective. However, the stress physiology of trees, perennial and woody plants, is far from being fully understood. For that purpose, poplar plants were exposed to drought; the plants exhibited commonly reported drought stress traits in the different plant tissues. Leafy rooted cuttings of poplar were investigated through a proteomic approach in order to compare the water constraint response of two plant tissues, namely leaf and cambium. Sampling was realized during the drought period at 2 time points with increased drought intensity and 7 days after rewatering. Our data show that there is a difference in the moment of response to the water constraint between the two tissues, cambium being affected later than leaves. In leaves, drought induced a decrease in rubisco content, and an increase in the abundance of light harvesting complex proteins as well as changes in membrane-related proteins. In the cambial tissue, the salient proteome pattern change was the decrease of multiple proteins identified as bark storage proteins. After rewatering, almost all changes in cambial proteome disappeared whereas a significant number of leaf proteins appeared to be differentially regulated only during the recovery from drought. 相似文献
997.
998.
999.
Poiroux G Pitié M Culerrier R Lafont E Ségui B Van Damme EJ Peumans WJ Bernadou J Levade T Rougé P Barre A Benoist H 《PloS one》2011,6(8):e23315
Photochemotherapy is used both for solid tumors and in extracorporeal treatment of various hematologic disorders. Nevertheless, its development in oncology remains limited, because of the low selectivity of photosensitizers (PS) towards human tumor cells. To enhance PS efficiency, we recently covalently linked a porphyrin (TrMPyP) to a plant lectin (Morniga G), known to recognize with high affinity tumor-associated T and Tn antigens. The conjugation allowed a quick uptake of PS by Tn-positive Jurkat leukemia cells and efficient PS-induced phototoxicity. The present study was performed: (i) to evaluate the targeting potential of the conjugate towards tumor and normal cells and its phototoxicity on various leukemia cells, (ii) to investigate the mechanism of conjugate-mediated cell death. The conjugate: (i) strongly increased (×1000) the PS phototoxicity towards leukemic Jurkat T cells through an O-glycan-dependent process; (ii) specifically purged tumor cells from a 1∶1 mixture of Jurkat leukemia (Tn-positive) and healthy (Tn-negative) lymphocytes, preserving the activation potential of healthy lymphocytes; (iii) was effective against various leukemic cell lines with distinct phenotypes, as well as fresh human primary acute and chronic lymphoid leukemia cells; (iv) induced mostly a caspase-independent cell death, which might be an advantage as tumor cells often resist caspase-dependent cell death. Altogether, the present observations suggest that conjugation with plant lectins can allow targeting of photosensitizers towards aberrant glycosylation of tumor cells, e.g. to purge leukemia cells from blood and to preserve the normal leukocytes in extracorporeal photochemotherapy. 相似文献
1000.
A conserved cysteine motif is critical for rice ceramide kinase activity and function 总被引:1,自引:0,他引:1