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371.
Nolen-Walston R Bedenice D Rodriguez C Rushton S Bright A Fecteau ME Short D Majdalany R Tewari D Pedersen D Kiupel M Maes R Del Piero F 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(4):846-852
BACKGROUND: Eastern equine encephalitis (EEE) virus is a mosquito-borne togavirus (alphavirus) that causes severe (often fatal) encephalitis in many mammalian species, but it has not been reported previously in South American camelids. Hypothesis: South American camelids can become naturally infected with EEE virus and show encephalitic signs similar to those observed in other affected species. ANIMALS: Nine cases (8 alpacas and 1 llama, aged 3.5 weeks to 12 years) were identified; 4 of 9 were 510 weeks old. All cases were from the East Coast of the United States and presented in late summer and fall. METHODS: A retrospective study was performed to include confirmed cases of EEE in camelids in North America before 2006. RESULTS: Eight of nine (89%) camelids died or were euthanized in extremis, with the mean time to death of 2 days. Clinical signs were consistent with encephalitis and included fever, lethargy, ataxia, seizures, recumbency, torticollis, opisthotonus, and vestibular signs. No consistent hematologic abnormalities were identified, and cerebrospinal fluid contained an increased protein concentration in the single camelid analyzed. No successful therapy was identified. EEE was confirmed by alphavirus detection by using immunohistochemistry (IHC) and polymerase chain reaction (PCR) in the central nervous system (CNS) and by serology. Findings included polioencephalitis with lymphocytic perivascular cuffing; neutrophil infiltration; gliosis; neuron satellitosis; necrosis; and edema, with intracytoplasmic alphavirus within neurons and glial cells. No virus was detected in extraneural tissues. CONCLUSIONS AND CLINICAL IMPORTANCE: In endemic areas, EEE should be considered a differential diagnosis for young and adult camelids with CNS disease. Brain histopathology with indirect IHC or PCR is diagnostic. 相似文献
372.
Bergamin F Saurer L Neuhaus V McCullough KC Summerfield A 《Veterinary immunology and immunopathology》2007,120(3-4):115-123
‘B-cell activating factor belonging to the TNF family’ (BAFF) represents a cytokine produced by antigen presenting cells promoting B-cell maturation, activation and immunoglobulin class switching. In the present study, we demonstrate expression of BAFF on cultured monocyte-derived dendritic cells, which is further enhanced by interferon- or interferon-γ treatment. From these cells, porcine BAFF was cloned and the recombinant protein was expressed in mammalian cells with and without a FLAG tag at the carboxyl terminus. Only the protein without the FLAG tag was bioactive in vitro, and promoted B-cell survival and the differentiation of foot-and-mouth disease virus (FMDV)-specific memory B cells into antibody producing cells. Based on this result it was tested whether BAFF can enhance FMDV antibody responses in the context of a DNA vaccination. To this end, pigs were immunised with the anti-FMDV DNA vaccine plasmid pcDNA3.1/P1-2A3C3D and a pCI plasmid expressing porcine BAFF. Using a needle-free transdermal application method, also referred to as ‘jet injection’, pigs were vaccinated three times and their humoral response quantified by ELISA and a virus neutralisation test. After the third vaccination, three out of six animals vaccinated with the pcDNA3.1/P1-2A3C3D alone but none of the animals that also received the BAFF expressing plasmid had seroconverted. These data suggest that BAFF is not appropriate as a genetic adjuvant when applied as a simple co-injection with the antigen-encoding plasmid. 相似文献
373.
Mastrorilli C Dondi F Agnoli C Turba ME Vezzali E Gentilini F 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(1):3-10
BACKGROUND AND HYPOTHESIS: We retrospectively evaluated the clinicopathologic findings and outcome predictors in dogs with Leptospira interrogans Australis serogroup infections. ANIMALS AND METHODS: The medical records of 159 dogs that had a leptospiral microscopic agglutination test (MAT) performed between 2001 and 2004 were reviewed. RESULTS: Twenty dogs met serologic criteria for either symptomatic (16 dogs) or asymptomatic (4 dogs) infection caused by Leptospira interrogans Australis serogroup. Seven of 16 symptomatic dogs died or were euthanized and 9/16 recovered. Systemic inflammatory response syndrome (SIRS) was observed in 9/16 dogs. The presence of SIRS did not affect prognosis (P = .357). C-reactive protein (CRP) and haptoglobin (Hpt) concentrations were altered in all symptomatic dogs, but results did not differ significantly between survivors and nonsurvivors (P = .08 and P = .055, respectively). Conversely, the CRP to Hpt ratio (CRP/Hpt) was significantly increased in nonsurvivors. Disseminated intravascular coagulation (DIC) was diagnosed in 7/16 dogs. DIC did not significantly affect outcome (P = .126). Multiple organ involvement was present with renal failure in 16/16, liver damage in 12/16, cardiac damage in 11/16, and muscular damage in 8/16 dogs. CONCLUSIONS AND CLINICAL IMPORTANCE: Among the evaluated clinicopathologic biomarkers, serum albumin, cardiac troponin I, CRP/Hpt, urinary albumin, and urinary total protein to creatinine ratio were found to predict outcome and warrant evaluation in larger prospective studies. 相似文献
374.
Fabio Franco Stellari Sophia Lavrentiadou Francesca Ruscitti Sarah Jacca Valentina Franceschi Maurizio Civelli Chiara Carnini Gino Villetti Gaetano Donofrio 《Veterinary research》2014,45(1):8
Polymorphonuclear cells diapedesis has an important contribution to the induced Mannhemia haemolytica (M. haemolytica) infection lung inflammation and IL-8 is the primary polymorphonuclear chemoattractant. Using a bovine IL-8/luciferase transiently transgenized mouse model, the orchestration among M. haemolytica, IL-8 promoter activation and neutrophilia was followed in real time by in vivo image analysis. 相似文献
375.
S. Sundar Jani Heino Fabio de Oliveira Roque John P. Simaika Adriano S. Melo Jonathan D. Tonkin Davidson Gomes Nogueira Daniel Paiva Silva 《水产资源保护:海洋与淡水生态系统》2020,30(6):1238-1250
- Motivated by recent global initiatives for biodiversity conservation and restoration, this article reviews the gaps in our understanding of, and the challenges facing, freshwater macroinvertebrate biodiversity and conservation in tropical regions.
- This study revealed a lack of adequate taxonomic, phylogenetic, and ecological information for most macroinvertebrate groups, and consequently there are large‐scale knowledge gaps regarding the response of macroinvertebrate diversity to potential climate change and other human impacts in tropical regions.
- We propose ideas to reduce the impact of key drivers of declines in macroinvertebrate biodiversity, including habitat degradation and loss, hydrological alteration, overexploitation, invasive species, pollution, and the multiple impacts of climate change.
- The review also provides recommendations to enhance conservation planning in these systems (as well as providing clear management plans at local, regional, and national levels), integrated catchment management, the formulation of regulatory measures, the understanding of the determinants of macroinvertebrate diversity across multiple scales and taxonomic groups, and the collaboration between researchers and conservation professionals.
- It is suggested that the integrated use of macroinvertebrate biodiversity information in biomonitoring can improve ecosystem management. This goal can be facilitated in part by conservation psychology, marketing, and the use of the media and the Internet.
376.
Marcos Fabio Oliveira Marques Edemir Barbosa dos Santos Luís Fernando Pascholati Gusma?o 《林业研究》2015,26(2):479-485
The fungi have wide distribution in ecosystems and can be found colonizing various substrates,where they act as efficient decomposers,participating in cycling of nutrients.The present study aimed to assess the diversity,richness and composition of filamentous fungi in leaf litter and aerial litter in a semi-deciduous forest in the Chapada Diamantina,Bahia,Brazil.Samples of leaf litter and aerial litter were collected monthly from October/2009 to September/2010 in eight installments in the studied area.Those samples were washed,placed in moist chambers and incubated.47 taxa were identified,37 in leaf litter and 35 in aerial litter,with 25 species common to both.A similarity of 69 % according to Sorensen index.The similarity was considered low when the sample points were compared to the same litter.Most fungi showed sporadic intervals. 相似文献
377.
378.
Daniel Duarte da Silveira Patrícia Iana Schmidt Gabriel Soares Campos Lucas de Vargas Fabio Ricardo Pablos de Souza Vanerlei Mozaquatro Roso Arione Augusti Boligon 《Animal Science Journal》2021,92(1):e13611
Covariance components were estimated for growth traits (BW, birth weight; WW, weaning weight; YW, yearling weight), visual scores (BQ, breed quality; CS, conformation; MS, muscling; NS, navel; PS, finishing precocity), hip height (HH), and carcass traits (BF, backfat thickness; LMA, longissimus muscle area) measured at yearling. Genetic gains were obtained and validation models on direct and maternal effects for BW and WW were fitted. Genetic correlations of growth traits with CS, PS, MS, and HH ranged from 0.20 ± 0.01 to 0.94 ± 0.01 and were positive and low with NS (0.11 ± 0.01 to 0.20 ± 0.01) and favorable with BQ (0.14 ± 0.02 to 0.37 ± 0.02). Null to moderate genetic correlations were obtained between growth and carcass traits. Genetic gains were positive and significant, except for BW. An increase of 0.76 and 0.72 kg is expected for BW and WW, respectively, per unit increase in estimated breeding value (EBV) for direct effect and an additional 0.74 and 1.43, respectively, kg per unit increase in EBV for the maternal effect. Monitoring genetic gains for HH and NS is relevant to maintain an adequate body size and a navel morphological correction, if necessary. Simultaneous selection for growth, morphological, and carcass traits in line with improve maternal performance is a feasible strategy to increase herd productivity. 相似文献
379.
380.
Maria A. Rao Fabio Russo Rita Berisio Liliana Gianfreda 《Soil biology & biochemistry》2007,39(2):493-504
Prion proteins are regarded as the main agents of transmissible spongiform encephalopathies. Understanding their fate in soil may be crucial to elucidate the dissemination of the prion in the environment, associated with a possible transmission of infectivity. Studies were performed with simplified model systems, derived by the birnessite-mediated oxidative polymerization of catechol, which simulate processes naturally occurring in soil. A benign full-length recombinant purified ovine protein (PrP) (residues 23-234), as well as a truncated-form ovPrP (tPrP) (103-234) were utilized. Catechol and prion protein interacted under experimental conditions that reproduced the interaction of PrP with soluble organic matter or with insoluble organic matter during or after formation of catechol polymers. PrP stability in all buffers and chemicals was preliminarily monitored by circular dicroism (CD) measurements. The disappearance of protein molecules from the solution, the decrease of UV-Visible absorbance of supernatants, and the FT-IR spectra and the elemental analyses of solid-phase residues indicated that both PrP and tPrP were involved in catechol polymerization by birnessite. Furthermore, a clear flocculation of soluble catechol-protein polymeric products in solid aggregates was observed when PrP was added to the supernatants. Different kinds of extracting agents were not able to desorb/extract PrP as well as tPrP from the formed solid aggregates, thereby highlighting the high stability of protein-organic and -organo-mineral complexes. 相似文献