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191.
Futuna is a small Polynesian island in the South Pacific with a population of 3,612 in 2013. The first human leptospirosis case was confirmed in 1997. Active surveillance started in 2004. Cases were confirmed by PCR or real time PCR, or by serology using MAT or a combination of IgM-ELISA and MAT. A retrospective analysis of surveillance data shows that the disease was endemic with a mean annual incidence of 844 cases per 100,000 over an 11-year period from 2004 to 2014. An epidemic peak as high as 1,945 cases per 100,000 occurred in 2008. Serogroup Australis was predominant until 2007, Icterohaemorrhagiae was dominant afterwards. Cluster analysis revealed different hot spots over time. Lifestyle habits, such as walking barefoot in irrigated taro fields or pig pens probably contributed to contamination from the swine and rodent reservoirs to humans. Severe forms were rare, and the case fatality rate was 0.5%. The medical community and general population were aware of leptospirosis and rapid treatment with amoxycillin was the main treatment, probably contributing to this low fatality rate. 相似文献
192.
Jian-Guo Huang Yaling Zhang Minhuang Wang Xiaohan Yu Annie Deslauriers Patrick Fonti Eryuan Liang Harri Mäkinen Walter Oberhuber Cyrille B. K. Rathgeber Roberto Tognetti Václav Treml Bao Yang Lihong Zhai Jiao-Lin Zhang Serena Antonucci Yves Bergeron Jesus Julio Camarero Filipe Campelo Katarina Čufar Henri E. Cuny Martin De Luis Marek Fajstavr Alessio Giovannelli Jožica Gričar Andreas Gruber Vladimír Gryc Aylin Güney Tuula Jyske Jakub Kašpar Gregory King Cornelia Krause Audrey Lemay Feng Liu Fabio Lombardi Edurne Martinez del Castillo Hubert Morin Cristina Nabais Pekka Nöjd Richard L. Peters Peter Prislan Antonio Saracino Vladimir V. Shishov Irene Swidrak Hanuš Vavrčík Joana Vieira Qiao Zeng Yu Liu Sergio Rossi 《Global Change Biology》2023,29(6):1606-1617
Despite growing interest in predicting plant phenological shifts, advanced spring phenology by global climate change remains debated. Evidence documenting either small or large advancement of spring phenology to rising temperature over the spatio-temporal scales implies a potential existence of a thermal threshold in the responses of forests to global warming. We collected a unique data set of xylem cell-wall-thickening onset dates in 20 coniferous species covering a broad mean annual temperature (MAT) gradient (−3.05 to 22.9°C) across the Northern Hemisphere (latitudes 23°–66° N). Along the MAT gradient, we identified a threshold temperature (using segmented regression) of 4.9 ± 1.1°C, above which the response of xylem phenology to rising temperatures significantly decline. This threshold separates the Northern Hemisphere conifers into cold and warm thermal niches, with MAT and spring forcing being the primary drivers for the onset dates (estimated by linear and Bayesian mixed-effect models), respectively. The identified thermal threshold should be integrated into the Earth-System-Models for a better understanding of spring phenology in response to global warming and an improved prediction of global climate-carbon feedbacks. 相似文献
193.
Vanessa Cutts Dagmar M. Hanz Martha Paola Barajas-Barbosa Franziska Schrodt Manuel J. Steinbauer Carl Beierkuhnlein Pierre Denelle José María Fernández-Palacios Pierre Gaüzère Matthias Grenié Severin D. H. Irl Nathan Kraft Holger Kreft Brian Maitner François Munoz Wilfried Thuiller Cyrille Violle Patrick Weigelt Richard Field Adam C. Algar 《Ecology letters》2023,26(4):504-515
Current models of island biogeography treat endemic and non-endemic species as if they were functionally equivalent, focussing primarily on species richness. Thus, the functional composition of island biotas in relation to island biogeographical variables remains largely unknown. Using plant trait data (plant height, leaf area and flower length) for 895 native species in the Canary Islands, we related functional trait distinctiveness and climate rarity for endemic and non-endemic species and island ages. Endemics showed a link to climatically rare conditions that is consistent with island geological change through time. However, functional trait distinctiveness did not differ between endemics and non-endemics and remained constant with island age. Thus, there is no obvious link between trait distinctiveness and occupancy of rare climates, at least for the traits measured here, suggesting that treating endemic and non-endemic species as functionally equivalent in island biogeography is not fundamentally wrong. 相似文献
194.
Seaweed liquid fertilizer fromAscophyllum nodosum contains elicitors of plantd-glycanases 总被引:1,自引:0,他引:1
Pascale Patier Jean-Claude Yvin Bernard Kloareg Yvette Liénart Cyrille Rochas 《Journal of applied phycology》1993,5(3):343-349
The structure of the major component contained in a liquid seaweed extract prepared fromAscophyllum nodosum (Phaeophyta, Fucales) was investigated. The extract was fractionated by gel permeation chromatography, and the various fractions were analysed by GLC, HPLC,13C NMR spectroscopy and mass spectrometry. All fractions were derivatives of the branched -d-(13) glucan known as laminaran. They were capable of elicitingd-glycanase activities (laminaranase, -amylase) inRubus fruticosus suspended-cell cultures. 相似文献
195.
Oumarou Traoré Issa Wonni Gilles Cellier Fousseni Boro Agathe Allibert Cyrille Tinlé Zombré Léonard Somgnogdin Ouédraogo Irénée Somda 《Journal of Phytopathology》2023,171(1):1-11
Bacterial wilt caused by the Ralstonia solanacearum species complex (RSSC) is a disease that negatively affects the cultivation of Solanaceae crops in Burkina Faso. Knowledge of the pathogen diversity is essential to deploy locally adapted control methods. In this study, diseased plants showing typical bacterial wilt symptoms were collected in the three main agroclimatic zones of Burkina Faso for the detection of RSSC isolates. Strain characterization was achieved through a phylogenetic and pathogenicity diversity assessment. A total of 102 isolates were sampled, and Phylotype I (Ralstonia pseudosolanacearum) was predominant (n = 101; sequevars 14, 31, 34, and 46). The remaining isolate was characterized as Phylotype IIA-35 (Ralstonia solanacearum). Phylotypes I-31 and I-46 were predominant and both characterized as the most the aggressive group of strains amongst a subset of 33 representative isolates. Our findings provide valuable information as regard RSSC diversity that breeders and resistance programme should target in order to fight this pathogen in Burkina Faso and around the world. 相似文献
196.
Franch-Marro X Marchand O Piddini E Ricardo S Alexandre C Vincent JP 《Development (Cambridge, England)》2005,132(4):659-666
The two glypicans Dally and Dally-like have been implicated in modulating the activity of Wingless, a member of the Wnt family of secreted glycoprotein. So far, the lack of null mutants has prevented a rigorous assessment of their roles. We have created a small deletion in the two loci. Our analysis of single and double mutant embryos suggests that both glypicans participate in normal Wingless function, although embryos lacking maternal and zygotic activity of both genes are still capable of transducing the signal from overexpressed Wingless. Genetic analysis of dally-like in wing imaginal discs leads us to a model whereby, at the surface of any given cell of the epithelium, Dally-like captures Wingless but instead of presenting it to signalling receptors expressed in this cell, it passes it on to neighbouring cells, either for paracrine signalling or for further transport. In the absence of dally-like, short-range signalling is increased at the expense of long-range signalling (reported by the expression of the target gene distalless) while the reverse is caused by Dally-like overexpression. Thus, Dally-like act as a gatekeeper, ensuring the sharing of Wingless among cells along the dorsoventral axis. Our analysis suggests that the other glypican, Dally, could act as a classical co-receptor. 相似文献
197.
Orset C Parrot S Sauvinet V Cottet-Emard JM Bérod A Pequignot JM Denoroy L 《Neurochemistry international》2005,46(8):623-633
Although many studies have revealed alterations in neurotransmission during ischaemia, few works have been devoted to the neurochemical effects of mild hypoxia, a situation encountered during life in altitude or in several pathologies. In that context, the present work was undertaken to determine the in vivo mechanisms underlying the striatal dopamine efflux induced by mild hypoxaemic hypoxia. For that purpose, the extracellular concentrations of dopamine and its metabolite 3,4-dihydroxyphenyl acetic acid were simultaneously measured using brain microdialysis during acute hypoxic exposure (10% O2, 1 h) in awake rats. Hypoxia induced a +80% increase in dopamine. Application of the dopamine transporters inhibitor, nomifensine (10 μM), just before the hypoxia prevented the rise in dopamine during the early part of hypoxia; in contrast the application of nomifensine after the beginning of hypoxia, failed to alter the increase in dopamine. Application of the voltage-dependent Na+ channel blocker tetrodotoxin abolished the increase in dopamine, whether administered just before or after the beginning of hypoxia. These data show that the neurochemical mechanisms of the dopamine efflux may change over the course of the hypoxic exposure, dopamine transporters being involved only at the beginning of hypoxia. 相似文献
198.
The nuclear import signal of snRNPs is composed of two essential components, the m(3)G cap structure of the snRNA and the Sm core NLS carried by the Sm protein core complex. We have previously proposed that, in yeast, this last determinant is represented by a basic-rich protuberance formed by the C-terminal extensions of Sm proteins. In mammals, as well as in other organisms, this component has not yet been precisely defined. Using GFP-Sm fusion constructs and immunolocalization as well as biochemical experiments, we show here that the C-terminal domains of human SmD1 and SmD3 proteins possess nuclear localization properties. Deletions of these domains increase cytoplasmic fluorescence and cytoplasmic localization of GFP-Sm mutant fusion alleles. Our results are consistent with a model in which the Sm core NLS is evolutionarily conserved and composed of a basic-rich protuberance formed by C-terminal domains of different Sm subtypes. 相似文献
199.
Tissue distribution and evolution of fructosamine 3-kinase and fructosamine 3-kinase-related protein
Delplanque J Delpierre G Opperdoes FR Van Schaftingen E 《The Journal of biological chemistry》2004,279(45):46606-46613
Fructosamine 3-kinase (FN3K) and FN3K-related protein (FN3K-RP) catalyze the phosphorylation of the Amadori products ribulosamines, psicosamines, and, in the case of FN3K, fructosamines. BLAST searches in chordate genomes revealed two genes encoding proteins homologous to FN3K or FN3K-RP in various mammals and in chicken but only one gene, encoding a protein more similar to FN3K-RP than to FN3K, in fishes and the sea squirt Ciona intestinalis. This suggests that a gene duplication event occurred after the fish radiation and that the FN3K gene evolved more rapidly than the FN3K-RP gene. In agreement with this distribution, only one enzyme, phosphorylating ribulosamines and psicosamines but not fructosamines, was found in the tissues from a fish (Clarias gariepinus), whereas two enzymes with specificities similar to either FN3K or FN3K-RP were found in mouse, rat, and chicken tissues. FN3K is particularly active in brain, heart, kidney, and skeletal muscle. Its activity is also relatively elevated in erythrocytes from man, rat, and mouse but barely detectable in erythrocytes from chicken and pig, which correlates well with the low intracellular concentration of glucose in erythrocytes from these species. This is in keeping with the specific role of FN3K to repair protein damage caused by glucose. FN3K-RP was more evenly distributed in tissues, except for skeletal muscle where its activity was particularly low. This may be related to low activity of the pentose phosphate pathway in this tissue, as suggested by assays of glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase. This finding, together with the high affinity of FN3K-RP for ribulosamines, suggests that this enzyme may serve to repair damage caused by the powerful glycating agent, ribose 5-phosphate. 相似文献
200.