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271.
272.
Olivier JT Briët Gawrie NL Galappaththy Flemming Konradsen Priyanie H Amerasinghe Felix P Amerasinghe 《Malaria journal》2005,4(1):1-11
In Vietnam, a large proportion of all malaria cases and deaths occurs in the central mountainous and forested part of the country. Indeed, forest malaria, despite intensive control activities, is still a major problem which raises several questions about its dynamics. A large-scale malaria morbidity survey to measure malaria endemicity and identify important risk factors was carried out in 43 villages situated in a forested area of Ninh Thuan province, south central Vietnam. Four thousand three hundred and six randomly selected individuals, aged 10–60 years, participated in the survey. Rag Lays (86%), traditionally living in the forest and practising "slash and burn" cultivation represented the most common ethnic group. The overall parasite rate was 13.3% (range [0–42.3] while Plasmodium falciparum seroprevalence was 25.5% (range [2.1–75.6]). Mapping of these two variables showed a patchy distribution, suggesting that risk factors other than remoteness and forest proximity modulated the human-vector interactions. This was confirmed by the results of the multivariate-adjusted analysis, showing that forest work was a significant risk factor for malaria infection, further increased by staying in the forest overnight (OR= 2.86; 95%CI [1.62; 5.07]). Rag Lays had a higher risk of malaria infection, which inversely related to education level and socio-economic status. Women were less at risk than men (OR = 0.71; 95%CI [0.59; 0.86]), a possible consequence of different behaviour. This study confirms that malaria endemicity is still relatively high in this area and that the dynamics of transmission is constantly modulated by the behaviour of both humans and vectors. A well-targeted intervention reducing the "vector/forest worker" interaction, based on long-lasting insecticidal material, could be appropriate in this environment. 相似文献
273.
Skilled grasp is a sensorimotor process requiring the brain to extract sensory cues from the environment to shape a motor command. Although a large body of literature has focused on which brain areas either integrate the visual object's properties or control the motor output, it is still unclear how grasp-related information is transferred from one area to another. Understanding interactions between brain areas is crucial for the study of visuomotor transformations. Recently, new advances in both human and non-human primates have shown it is possible to study cortico-cortical interactions during different task contexts. This sheds new light on how brain areas are integrated in a dynamic network for controlling grasping actions. 相似文献
274.
275.
Charlie C. Nicholson Kimiora L. Ward Neal M. Williams Rufus Isaacs Keith S. Mason Julianna K. Wilson Julia Brokaw Larry J. Gut Nikki L. Rothwell Thomas J. Wood Sujaya Rao George D. Hoffman Jason Gibbs Robbin W. Thorp Taylor H. Ricketts 《Ecology letters》2020,23(2):326-335
Supporting ecosystem services and conserving biodiversity may be compatible goals, but there is concern that service‐focused interventions mostly benefit a few common species. We use a spatially replicated, multiyear experiment in four agricultural settings to test if enhancing habitat adjacent to crops increases wild bee diversity and abundance on and off crops. We found that enhanced field edges harbored more taxonomically and functionally abundant, diverse, and compositionally different bee communities compared to control edges. Enhancements did not increase the abundance or diversity of bees visiting crops, indicating that the supply of pollination services was unchanged following enhancement. We find that actions to promote crop pollination improve multiple dimensions of biodiversity, underscoring their conservation value, but these benefits may not be spilling over to crops. More work is needed to identify the conditions that promote effective co‐management of biodiversity and ecosystem services. 相似文献
276.
277.
Karen M. Page Simon W. Rothwell Annette C. Dolphin 《The Journal of biological chemistry》2016,291(39):20402-20416
CaVβ subunits interact with the voltage-gated calcium channel CaV2.2 on a site in the intracellular loop between domains I and II (the I-II loop). This interaction influences the biophysical properties of the channel and leads to an increase in its trafficking to the plasma membrane. We have shown previously that a mutant CaV2.2 channel that is unable to bind CaVβ subunits (CaV2.2 W391A) was rapidly degraded (Waithe, D., Ferron, L., Page, K. M., Chaggar, K., and Dolphin, A. C. (2011) J. Biol. Chem. 286, 9598–9611). Here we show that, in the absence of CaVβ subunits, a construct consisting of the I-II loop of CaV2.2 was directly ubiquitinated and degraded by the proteasome system. Ubiquitination could be prevented by mutation of all 12 lysine residues in the I-II loop to arginines. Including a palmitoylation motif at the N terminus of CaV2.2 I-II loop was insufficient to target it to the plasma membrane in the absence of CaVβ subunits even when proteasomal degradation was inhibited with MG132 or ubiquitination was prevented by the lysine-to-arginine mutations. In the presence of CaVβ subunit, the palmitoylated CaV2.2 I-II loop was protected from degradation, although oligoubiquitination could still occur, and was efficiently trafficked to the plasma membrane. We propose that targeting to the plasma membrane requires a conformational change in the I-II loop that is induced by binding of the CaVβ subunit. 相似文献
278.
279.
Inflammation in central nervous system injury 总被引:16,自引:0,他引:16
Allan SM Rothwell NJ 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2003,358(1438):1669-1677
Inflammation is a key component of host defence responses to peripheral inflammation and injury, but it is now also recognized as a major contributor to diverse, acute and chronic central nervous system (CNS) disorders. Expression of inflammatory mediators including complement, adhesion molecules, cyclooxygenase enzymes and their products and cytokines is increased in experimental and clinical neurodegenerative disease, and intervention studies in experimental animals suggest that several of these factors contribute directly to neuronal injury. Most notably, specific cytokines, such as interleukin-1 (IL-1), have been implicated heavily in acute neurodegeneration, such as stroke and head injury. In spite of their diverse presentation, common inflammatory mechanisms may contribute to many neurodegenerative disorders and in some (e.g. multiple sclerosis) inflammatory modulators are in clinical use. Inflammation may have beneficial as well as detrimental actions in the CNS, particularly in repair and recovery. Nevertheless, several anti-inflammatory targets have been identified as putative treatments for CNS disorders, initially in acute conditions, but which may also be appropriate to chronic neurodegenerative conditions. 相似文献
280.
The Rfp-Y region lies on the same microchromosome as the B-F/B-L region of the B complex, yet in contrast to the latter it is poorly characterised. To date it has been shown to contain at least two class I alpha-chain ( Y-F) genes, a class II B-chain gene and a C-type lectin-like gene. We describe the sequencing and analysis of some 20 kb of the Rfp-Y region, and identify several new genes. These include two novel C-type lectin-like genes ( Y-Lec1 and Y-Lec2) that differ strongly from the previously described C-type lectin-like gene found in the Rfp-Y region. We describe a complete genomic sequence of a class I alpha-chain ( Y-F) gene and its promoter from the Rfp-Y region. The predicted cDNA from this gene has high homology to the previously reported Y-F cDNAs. The promoter contains an altered enhancer A element. This portion of the Rfp-Y region also contains a truncated class II B-chain ( Y-LB) gene, as well as a large chicken repeat 1 (CR1) element. 相似文献