Thrombelastography in dogs admitted to an intensive care unit     

Catherine R. Wagg  Søren R. Boysen  Christian Bédard 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2009,38(4):453-461

Background: Underlying conditions in dogs admitted to an intensive care unit (ICU) can cause hemostatic dysfunction. Thrombelastography (TEG) may be useful in detecting hemostatic alterations as compared with standard coagulation tests. Objectives: The purpose of this study was to compare TEG results and those of standard coagulation tests in identifying hemostatic dysfunction in dogs admitted to an ICU and to investigate associations among the variables measured. Methods: Tissue factor‐activated TEG analysis, d ‐dimer and fibrinogen concentrations, antithrombin (AT) activity, prothrombin time (PT), activated partial thromboplastin time (aPTT), and platelet count were measured using standard techniques on 27 dogs admitted to ICU with a disease known to be associated with hemostatic dysfunction and in 31 clinically healthy control dogs. Results were compared between groups using nonparametric tests and κ analysis; principal component analysis (PCA) and Spearman rank correlation were used to measure associations among variables. Results: Fourteen of 27 ICU dogs had abnormal TEG tracings, which were used to classify the dogs as hypercoagulable (n=11), hypocoagulable (n=3), or normocoagulable (n=13). Hypercoagulable dogs had significantly increased d ‐dimer (P=.03) and fibrinogen (P=.01) concentrations compared with normocoagulable dogs. In ICU dogs, positive associations were identified between maximum amplitude (MA), α‐angle, fibrinogen concentration, and platelet count, and between PT, aPTT, and reaction time (R). Significant correlations were found between MA and fibrinogen (r_s=.76, P<.001) and between reaction time (R) and PT (r_s=.51, P=.003). Conclusions: TEG was useful in detecting hemostatic dysfunction in dogs in an ICU. Positive associations among variables may provide insight as to how overall coagulation status reflects alterations in clot strength and coagulation time. Dogs with TEG tracings indicative of hypercoagulability are likely in procoagulant states. Future studies of the incidence of thrombotic complications in dogs with hypercoagulable TEG tracings are warranted.  相似文献   

Human α-defensin 6 promotes mucosal innate immunity through self-assembled peptide nanonets     

Chu H  Pazgier M  Jung G  Nuccio SP  Castillo PA  de Jong MF  Winter MG  Winter SE  Wehkamp J  Shen B  Salzman NH  Underwood MA  Tsolis RM  Young GM  Lu W  Lehrer RI  Bäumler AJ  Bevins CL 《Science (New York, N.Y.)》2012,337(6093):477-481

Defensins are antimicrobial peptides that contribute broadly to innate immunity, including protection of mucosal tissues. Human α-defensin (HD) 6 is highly expressed by secretory Paneth cells of the small intestine. However, in contrast to the other defensins, it lacks appreciable bactericidal activity. Nevertheless, we report here that HD6 affords protection against invasion by enteric bacterial pathogens in vitro and in vivo. After stochastic binding to bacterial surface proteins, HD6 undergoes ordered self-assembly to form fibrils and nanonets that surround and entangle bacteria. This self-assembly mechanism occurs in vivo, requires histidine-27, and is consistent with x-ray crystallography data. These findings support a key role for HD6 in protecting the small intestine against invasion by diverse enteric pathogens and may explain the conservation of HD6 throughout Hominidae evolution.  相似文献   

Glacial survival of boreal trees in northern Scandinavia     

Parducci L  Jørgensen T  Tollefsrud MM  Elverland E  Alm T  Fontana SL  Bennett KD  Haile J  Matetovici I  Suyama Y  Edwards ME  Andersen K  Rasmussen M  Boessenkool S  Coissac E  Brochmann C  Taberlet P  Houmark-Nielsen M  Larsen NK  Orlando L  Gilbert MT  Kjær KH  Alsos IG  Willerslev E 《Science (New York, N.Y.)》2012,335(6072):1083-1086

It is commonly believed that trees were absent in Scandinavia during the last glaciation and first recolonized the Scandinavian Peninsula with the retreat of its ice sheet some 9000 years ago. Here, we show the presence of a rare mitochondrial DNA haplotype of spruce that appears unique to Scandinavia and with its highest frequency to the west-an area believed to sustain ice-free refugia during most of the last ice age. We further show the survival of DNA from this haplotype in lake sediments and pollen of Tr?ndelag in central Norway dating back ~10,300 years and chloroplast DNA of pine and spruce in lake sediments adjacent to the ice-free And?ya refugium in northwestern Norway as early as ~22,000 and 17,700 years ago, respectively. Our findings imply that conifer trees survived in ice-free refugia of Scandinavia during the last glaciation, challenging current views on survival and spread of trees as a response to climate changes.  相似文献   

Long-term monitoring of tropical bats for anthropogenic impact assessment: Gauging the statistical power to detect population change     

Christoph F.J. Meyer  Ludmilla M.S. Aguiar  Julio Baumgarten  Jean-François Cosson  Jakob Fahr  Neil Furey  Robert Hodgkison  Kirsten G. Jung  Thomas H. Kunz  Isabel Moya  Paul A. Racey  Erica M. Sampaio  Christian C. Voigt  Christa D. Weise 《Biological conservation》2010,143(11):2797-2807

Bats are ecologically important mammals in tropical ecosystems; however, their populations face numerous environmental threats related to climate change, habitat loss, fragmentation, hunting, and emerging diseases. Thus, there is a pressing need to develop and implement large-scale networks to monitor trends in bat populations over extended time periods. Using data from a range of Neotropical and Paleotropical bat assemblages, we assessed the ability for long-term monitoring programs to reliably detect temporal trends in species abundance. We explored the magnitude of within-site temporal variation in abundance and evaluated the statistical power of a suite of different sampling designs for several different bat species and ensembles. Despite pronounced temporal variation in abundance of most tropical bat species, power simulations suggest that long-term monitoring programs (?20 years) can detect population trends of 5% per year or more with adequate statistical power (?0.9). However, shorter monitoring programs (?10 years) have insufficient power for trend detection. Overall, our analyses demonstrate that a monitoring program extending over 20 years with four surveys conducted biennially on five plots per monitoring site would have the potential for detecting a 5% annual change in abundance for a suite of bat species from different ensembles. The likelihood of reaching adequate statistical power was sensitive to initial species abundance and the magnitude of count variation, stressing that only the most abundant species in an assemblage and those with generally low variation in abundance should be considered for detailed population monitoring.  相似文献   

Identification of an aliphatic epoxide and the corresponding dihydrodiol as novel congeners of zearalenone in cultures of Fusarium graminearum     

Pfeiffer E  Hildebrand AA  Becker C  Schnattinger C  Baumann S  Rapp A  Goesmann H  Syldatk C  Metzler M 《Journal of agricultural and food chemistry》2010,58(22):12055-12062

The mycotoxin zearalenone (ZEN) is produced by various Fusarium fungi and frequently found as a contaminant in food and feed. There are reports in the literature that several closely related analogues of ZEN are also formed in cultures of Fusarium species. We have therefore analyzed the organic extract from a 40 day culture of Fusarium graminearum by LC-DAD-MS and detected 15 compounds, which could be congeners of ZEN because of their ultraviolet, mass spectroscopy, and tandem mass spectroscopy spectra. In addition to confirming the previously reported α- and β-stereoisomers of 5-hydroxy-ZEN and 10-hydroxy-ZEN, we identified seven ZEN congeners for the first time. One of the major novel congeners was shown by nuclear magnetic resonance spectroscopy and chemical synthesis to have the structure of an aliphatic ZEN epoxide, whereas two minor products proved to be the corresponding dihydrodiols. In addition, three stereoisomers of a cyclization product of the dihydrodiols, carrying a spiro-acetal group, were identified as fungal products for the first time. The latter may be artifacts, because the ZEN epoxide and dihydrodiol are unstable under acidic conditions and rearrange easily to the spiro-acetal compounds.  相似文献   

Hybrid zones as a tool for identifying adaptive genetic variation in outbreeding forest trees: lessons from wild annual sunflowers (Helianthus spp.)     

Lexer C  Heinze B  Alia R  Rieseberg LH 《Forest Ecology and Management》2004,197(1-3):49-64

The identification and study of adaptively important genes in forest trees represents a formidable challenge because of their long generation spans. In annual or perennial herbs, formal genetic studies can be employed to identify the quantitative trait loci (QTLs) and/or candidate genes that underlie important traits, and the segregating populations can be transplanted into natural populations to measure the strength and direction of selection. However, the application of these methods to forest trees is difficult, because the creation of appropriate genetic material is extremely time-consuming in long-lived, woody plants, and lifetime fitness estimates are difficult or impossible to obtain. Although QTL mapping should in principle be feasible in wild intraspecific populations (as an alternative to artificial crosses), this approach is less likely to be successful in trees because LD (linkage disequilibrium) will decay quickly in large outbreeding plant populations. Within the present paper, we discuss a modified approach based on natural hybrid zones. We describe the use of wild annual sunflowers (Helianthus spp.) as a model for exploring the hybrid zone approach. Transplanted experimental hybrids allowed us to assess the adaptive value of individual chromosomal blocks in nature, and data on natural Helianthus hybrids suggest that similar approaches are possible in natural hybrid zones. Our results allowed us to test the role of hybridization in the origin of ecological divergence in wild sunflowers. In addition, they have practical implications for identifying adaptively important genes or QTLs in trees. This is exemplified by three temperate forest taxa, Populus (poplars, aspens, cottonwoods), Fraxinus (ash), and Quercus (oak). All three are diploid and important genomic tools are under development. Moreover, all three offer extensive hybrid zones whose likely age can be inferred from fossil data. Age data enables estimates of the size and frequency of chromosomal blocks in hybrids, thereby providing guidance in designing marker-based experiments. We predict that natural hybrid zones will be valuable tools for identifying the QTLs and/or candidate genes responsible for adaptive traits in forest trees.  相似文献   

Idiopathic acute onset myelopathy in cheetah (Acinonyx jubatus) cubs.     

Christian Walzer  Angelika Url  Nadia Robert  Anna Kübber-Heiss  Norbert Nowotny  Peter Schmidt 《Journal of zoo and wildlife medicine》2003,34(1):36-46

Numerous cases of ataxia, hind limb paresis, and paralysis have occurred in cheetah (Acinonyx jubatus) cubs over the past 10 yr within the European Endangered Species Program population, including 12 in mainland Europe, two in the British Isles, one in Namibia, and one in Dubai. The condition is the most important medical factor limiting European cheetah population growth. Eight cubs at the Salzburg Zoo, Austria, were affected. They demonstrated upper motor neuron lesions when alive and bilateral, symmetrical myelin degeneration of the spinal cord on necropsy. Ballooning of myelin sheaths surrounded mostly preserved axons, and no spheroids, characteristic of acute axonal degeneration, were found. Myelin loss markedly exceeded axonal degeneration. The syndrome's etiology is unclear, although viral, bacterial, parasitic, genetic, nutritional-metabolic, toxic, and physical causes have been considered.  相似文献   

Biological Control of Plant Diseases: The European Situation   总被引：3，自引：0，他引：3  

Claude Alabouvette  Chantal Olivain  Christian Steinberg 《European journal of plant pathology / European Foundation for Plant Pathology》2006,114(3):329-341

The most common approach to biological control consists of selecting antagonistic microorganisms, studying their modes of action and developing a biological control product. Despite progress made in the knowledge of the modes of action of these biological control agents (BCAs), practical application often fails to control disease in the fields. One of the reasons explaining this failure is that the bio-control product is used the same way as a chemical product. Being biological these products have to be applied in accordance with their ecological requirements. Another approach consists of induction of plant defence reactions. This can be done by application of natural substances produced by or extracted from microorganisms, plants, or algae. Since they do not aim at killing the pathogens, these methods of disease control are totally different from chemical control. Although promising, these methods have not been sufficiently implemented under field conditions. A third approach consists of choosing cultural practices that might decrease the incidence or severity of diseases. These methods include the choice of an appropriate crop rotation with management of the crop residues, application of organic amendments and the use of new technology such as the biological disinfestation of soils. Biological control practices need an integrative approach, and more knowledge than chemical control.  相似文献   

应用ＥＬＩＳＰＯＴ试验测定重组卡介苗诱导的Ｔ细胞应答   总被引：7，自引：1，他引：6  

焦新安  Richard Lo-Man  Edith D'eriaud  Nathalie Winter  Claude Leclerc  刘秀梵 《中国预防兽医学报》2001,23(1):46-49

应用免疫磁性分离技术去除免疫小鼠脾脏细胞中ＣＤ４^ 或ＣＤ8^ Ｔ细胞后，在酶免疫斑点试验中证实表达大肠杆菌ＭalE蛋白的重组卡介苗（rBCG.MalE)诱导的Ｔ细胞应答是ＣＤ４^ t细胞依赖的对MalE、PPD持异Ｔ细胞应答的动态分析结果表明，，rBCG.MalE、ＢＣＧ诱导的特异ＣＤ４^ T细胞应答存在Ｔh1/Th2平衡转换现象，即起始阶段为Ｔh1应答，一段时间后出现Ｔh2应答，并逐步形成Ｔh1/Th２混合应答。这些结果，分为枝杆菌Ｔ细胞应答规律提供了新的认识，同时，亦表明ＢＣＧ是优良的外源抗原表达与运送载体。  相似文献   

Maize landraces of the St. Lawrence-Great Lakes region of North America     

Christian Azar  Diane E. Mather  Robert I. Hamilton 《Euphytica》1997,98(3):141-148

Thirty-five white maize (Zea mays L.) landraces were obtained by the Indian Agricultural Program of Ontario (IAPO) from native farmers in Ontario and New York State between 1986 and 1989. These landraces probably belong to the racial complex Northern Flints and Flours. The 35 landraces, one experimental population and one control hybrid were evaluated in field experiments at two sites in 1993 and 1994. Data were collected on 24 traits in order to characterize and classify the IAPO landraces. Most quantitative traits examined exhibited considerable variation among the IAPO landraces. Variation was also observed within many of the landraces for ear and cob colour, and for endosperm texture. Most ears had eight rows of kernels, but there was some variation for this among and within landraces. Based on seven traits from the two sites in 1994, the IAPO population was grouped into 10 clusters by centroid clustering analysis. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献