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701.
No qualitative cladistic analysis has been performed previously for the subfamily classification of Pompilidae (Hymenoptera). In 1994 Shimizu proposed six subfamilies, but their validity and relationships remain inconclusive. The objective of this study was to perform a quantitative analysis of phylogenetic relationships of the Pompilidae, with emphasis on testing the validity of proposed subfamilies. Two cladistic analyses were performed based on morphological evidence. First, a maximum-parsimony analysis of Shimizu's original morphological data matrix (72 taxa by 54 characters) was conducted, with the data subjected to a heuristic search for the first time with phylogenetic software. The resulting strict-consensus cladogram yielded a monophyletic Ceropalinae that was sister group to a large polytomy containing members of the remaining five subfamilies. In a second analysis, several of Shimizu's characters were re-examined, and new characters and more taxa were added to the data set. Terminal taxa were coded as species rather than as generic abstractions, and 20 additional morphological characters were introduced. The analysis was based on 77 morphological characters derived from the adults of 84 taxa. This second analysis suggested that Notocyphinae sensu Shimizu (1994) was nested within Pompilinae and that Epipompilinae sensu Shimizu (1994) was nested within Ctenocerinae; neither should retain their status as a separate subfamily. Lastly, Chirodamus s .s., which historically has been a member of the Pepsinae, is placed within the Pompilinae with reservations rather than erecting a new subfamily. After these allowances were made, a strict consensus tree gave the following relationships: (Ceropalinae + (Pepsinae + (Ctenocerinae + Pompilinae))). 相似文献
702.
Ioana Streata January Weiner rd Marco Iannaconne Gayle McEwen Marius Sorin Ciontea Marian Olaru Rosanna Capparelli Mihai Ioana Stefan H. E. Kaufmann Anca Dorhoi 《PloS one》2016,11(9)
Genetic variants in the CARD9 gene predispose to inflammatory disorders and chronic infectious diseases. Tuberculosis (TB), a chronic infectious disease affecting the lung, is lethal in Card9-deficient mice. We hypothesized that polymorphisms in the CARD9 gene influence TB progression and disease-associated lung damage in humans. We tested genotype distributions of the CARD9 polymorphisms rs4077515, rs10781499 and rs10870077 in TB patients and healthy subjects in a Caucasian cohort. SNPs were in linkage disequilibrium and none of the haplotypes was significantly enriched in the TB group. We determined total and differential leukocyte count, erythrocyte sedimentation rate and plasma abundance of cytokines and chemokines as markers for systemic inflammation and scored chest X-rays to assess lung involvement in TB subjects. Most disease parameters segregated independently of the CARD9 haplotypes. In contrast to multifactorial chronic inflammation, selected genetic variants in the CARD9 gene leave host responses apparently unaffected in TB, at least in the population analyzed here. 相似文献
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Emmanuelle Robardet Evelyne Picard-Meyer Marianna Dobro?tana Ingrida Jaceviciene Katrin M?har Zita Mui?niece Gediminas Pridotkas Marius Masiulis Enel Niin Edvīns Ol?evskis Florence Cliquet 《PLoS neglected tropical diseases》2016,10(2)
Rabies is a fatal zoonosis that still causes nearly 70, 000 human deaths every year. In Europe, the oral rabies vaccination (ORV) of red foxes (Vulpes vulpes) was developed in the late 1970s and has demonstrated its effectiveness in the eradication of the disease in Western and some Central European countries. Following the accession of the three Baltic countries—Estonia, Latvia and Lithuania—to the European Union in 2004, subsequent financial support has allowed the implementation of regular ORV campaigns since 2005–2006. This paper reviews ten years of surveillance efforts and ORV campaigns in these countries resulting in the near eradication of the disease. The various factors that may have influenced the results of vaccination monitoring were assessed using generalized linear models (GLMs) on bait uptake and on herd immunity. As shown in previous studies, juveniles had lower bait uptake level than adults. For the first time, raccoon dogs (Nyctereutes procyonoides) were shown to have significantly lower bait uptake proportion compared with red foxes. This result suggests potentially altered ORV effectiveness in this invasive species compared to the red foxes. An extensive phylogenetic analysis demonstrated that the North-East European (NEE) rabies phylogroup is endemic in all three Baltic countries. Although successive oral vaccination campaigns have substantially reduced the number of detected rabies cases, sporadic detection of the C lineage (European part of Russian phylogroup) underlines the risk of reintroduction via westward spread from bordering countries. Vaccine induced cases were also reported for the first time in non-target species (Martes martes and Meles meles). 相似文献
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707.
Bogacz R Usher M Zhang J McClelland JL 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2007,362(1485):1655-1670
The leaky competing accumulator (LCA) is a biologically inspired model of choice. It describes the processes of leaky accumulation and competition observed in neuronal populations during choice tasks and it accounts for reaction time distributions observed in psychophysical experiments. This paper discusses recent analyses and extensions of the LCA model. First, it reviews the dynamics and examines the conditions that make the model achieve optimal performance. Second, it shows that nonlinearities of the type present in biological neurons improve performance when the number of choice alternatives increases. Third, the model is extended to value-based choice, where it is shown that nonlinearities in the value function explain risk aversion in risky choice and preference reversals in choice between alternatives characterized across multiple dimensions. 相似文献
708.
Amato P Parazols M Sancelme M Laj P Mailhot G Delort AM 《FEMS microbiology ecology》2007,59(2):242-254
This work constitutes the first large report on aerobic cultivable microorganisms present in cloud water. Seven cloud-event samples were collected at the Puy de D?me summit, and cultivation was performed leading to the isolation of 71 bacterial, 42 fungal and 15 yeast strains. Most of the fungi isolated were of Cladosporium or Trametes affiliation, and yeasts were of Cryptococcus affiliation. Bacteria, identified on the basis of their 16S rRNA gene sequence, were found to belong to Actinobacteria, Firmicutes, Proteobacteria (Alpha, Beta and Gamma subclasses) and Bacteroidetes phyla, and mainly to the genera Pseudomonas, Sphingomonas, Staphylococcus, Streptomyces, and Arthrobacter. These strains appear to be closely related to some bacteria described from cold environments, water (sea and freshwater), soil or vegetation. Comparison of the distribution of Gram-negative vs. Gram-positive bacteria shows that the number of Gram-negative bacteria is greater in summer than in winter. Finally, a very important result of this study concerns the ability of half of the tested strains to grow at low temperatures (5 degrees C): most of these are Gram-negative bacteria, and a few are even shown to be psychrophiles. On the whole, these results give a good picture of the microbial content of cloud water in terms of classification, and suggest that a large proportion of bacteria present in clouds have the capacity to be metabolically active there. This is of special interest with respect to the potential role of these microorganisms in atmospheric chemistry. 相似文献
709.
Fritz G. Parak Klaus Achterhold Simonetta Croci Marius Schmidt 《Journal of biological physics》2007,33(5-6):371-387
A physical model is reviewed which explains different aspects of protein dynamics consistently. At low temperatures, the molecules are frozen in conformational substates. Their average energy is 3/2RT. Solid-state vibrations occur on a time scale of femtoseconds to nanoseconds. Above a characteristic temperature, often called the dynamical transition temperature, slow modes of motions can be observed occurring on a time scale between about 140 and 1 ns. These motions are overdamped, quasidiffusive, and involve collective motions of segments of the size of an α-helix. Molecules performing these types of motion are in the “flexible state”. This state is reached by thermal activation. It is shown that these motions are essential for conformational relaxation. Based on this picture, a new approach is proposed to understand conformational changes. It connects structural fluctuations and conformational transitions. 相似文献
710.
Hauck SM Schoeffmann S Amann B Stangassinger M Gerhards H Ueffing M Deeg CA 《Journal of proteome research》2007,6(6):2121-2131
Spontaneous equine recurrent uveitis (ERU) is an incurable autoimmune disease affecting the eye. Although retinal-autoantigen specific T-helper 1 cells have been demonstrated to trigger disease progression and relapses, the molecular processes leading to retinal degeneration and consequent blindness remain unknown. To elucidate such processes, we studied changes in the total retinal proteome of ERU-diseased horses compared to healthy controls. Severe changes in the retinal proteome were found for several markers for blood-retinal barrier breakdown and whose emergence depended upon disease severity. Additionally, uveitic changes in the retina were accompanied by upregulation of aldose 1-epimerase, selenium-binding protein 1, alpha crystallin A chain, phosphatase 2A inhibitor (SET), and glial fibrillary acidic protein (GFAP), the latter indicating an involvement of retinal Mueller glial cells (RMG) in disease process. To confirm this, we screened for additional RMG-specific markers and could demonstrate that, in uveitic retinas, RMG concomitantly upregulate vimentin and GFAP and downregulate glutamine synthetase. These expression patterns suggest for an activated state of RMG, which further downregulate the expression of pigment epithelium-derived factor (PEDF) and begin expressing interferon-gamma, a pro-inflammatory cytokine typical for T-helper 1 cells. We thus propose that RMG may play a fatal role in uveitic disease progression by directly triggering inflammatory processes through the expression and secretion of interferon-gamma. 相似文献