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31.
OBJECTIVE: To determine whether exposure of canine cancer cells to histone deacetylase (HDAC) inhibitors S(+)-N-hydroxy-4-(3-methyl-2-phenyl-butyrylamino)benzamide (OSU-HDAC42) or suberoylanilide hydroxamic acid (SAHA) results in increased histone acetylation and decreased cell viability and whether any changes in viability involve induction of apoptosis or alterations in progression of the cell cycle. Sample POPULATION: 9 canine cancer cell lines. PROCEDURES: Cells from 9 canine cancer cell lines were treated with dimethyl sulfoxide vehicle, OSU-HDAC42, or SAHA, then assays of cell viability were performed. Histone acetylation was assessed by use of western blot analysis. Apoptosis was assessed via ELISA to detect fragmentation of cytoplasmic nucleosomal DNA and western blot analysis to detect cleavage of caspase 3. Cell cycle analysis was performed by use of propidium iodide staining and flow cytometry. RESULTS-Concentrations of OSU-HDAC42 and SAHA required to achieve 50% inhibition of cell viability (IC(50)) were reached in cells of 6 and 4 canine cancer cell lines, respectively, and ranged from approximately 0.4 to 1.3 microM for OSU-HDAC42 and 0.6 to 4.8 microM for SAHA. Cells from T-cell lymphoma, mast cell tumor, osteosarcoma, and histiocytic sarcoma lines were most sensitive to HDAC inhibition, with IC(50)s of < 1 microM for OSU-HDAC42 and < 5 microM for SAHA. Induction of apoptosis was indicated via cleavage of caspase 3 and increases in cytoplasmic nucleosomes and the subG(1) cell population. CONCLUSIONS AND CLINICAL RELEVANCE: Micromolar concentrations of HDAC inhibitors OSU-HDAC42 and SAHA induced histone acetylation, cytotoxicity, and apoptosis in canine cancer cells. In general, OSU-HDAC42 was more potent than SAHA.  相似文献   
32.
Journal of Crop Science and Biotechnology - Fine mapping quantitative trait loci (QTL) and understanding the molecular mechanism and underlying functions of genes are vital to the advancement of...  相似文献   
33.

A study on the growth and reproductive performance of two rabbit breeds was undertaken. Data on 588 kits and 97 does of California White and 574 kits and 90 does of New Zealand White rabbits reared under hot and humid environment in Ghana were taken. The reproductive performance of the two breeds, in terms of litter size at birth and weaning, litter weight at birth and weaning, kindling interval, age at sexual maturity, and gestation length as influenced by breed, season of kindling (rainy and dry), year of kindling (2005–2012), and parity (first to sixth and over) were determined. The performance of California White in terms of litter size at birth, at weaning, kit weight at birth, and age at first kindling was 5.9?±?0.2, 4.6?±?0.1, 54.7?±?0.4 g, and 159.8?±?0.2 days, respectively. That of New Zealand White was 5.9?±?0.1, 5.1?±?0.1, 55.2?±?1.0 g, and 159.9?±?0.2 days, respectively. The results obtained also showed a significant breed effects on kit weight at birth, litter weight at weaning, and mortality; whereas no significant differences (p?>?0.05) were observed between the two breeds regarding the other traits measured. Parity had significant effects (p?<?0.05) on all the growth and reproductive parameters measured with the exception of age at first kindling. Year of kindling also had significant effect on litter weight at birth, kit weight at birth, and at weaning (p?<?0.05) but did not have any significant effect on the age at sexual maturity and mortality. Season also had significant (p?<?0.05) effects on kit weight at birth, gestation length, kindling interval, and mortality with better performance experienced during the rainy season.

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34.
The environment in which the horse is reared affects its ability to maintain thermal balance which is in turn related to thermal characteristics and regulatory physiological mechanisms. In this study a multivariate analysis of physiological traits in relation to heat tolerance in horses was carried out in the Federal District, Brazil. The aim was to test the ability of these analyses to separate groups of animals and determine which physiological traits are most important in the adaptation to heat stress. Forty adult horses (4 to 13 years) were used, ten from each of four different genetic groups (English thoroughbred, Brazilian showjumper, crossbred and Breton). The traits examined included heart and breathing rate, rectal temperature as well as blood parameters. The data underwent multivariate statistical analysis including cluster, discriminate and canonical using Statistical Analysis System - SAS ® procedures CLUSTER, STEPDISC, CANCORR and DISCRIM. The tree diagram showed clear distances between groups studied and canonical analysis was able to separate individuals in groups. The discriminate analysis identified the variables which were most important in separating these groups. The multivariate analysis was able to separate the animals into groups with RR, HR and RT being important in this separation.  相似文献   
35.
An outbreak of a new and severe disease was observed in Eucalyptus plantations of Bahia state, Brazil. An Ascomycota fungus has been frequently associated with the main symptoms of the disease namely leaf spot, branch cankers, shoot blight, defoliation, and dieback. Based on morphological characteristics, phylogenetic analysis (ITS and TEF-1α genes), and pathogenicity test on Eucalyptus plants, Pseudoplagiostoma eucalypti was identified as the causal agent of the disease. Although P. eucalytpi has been known from in Brazil since 1998, this is the first report of it causing severe disease and die-back on Eucalyptus spp. and we also record new symptoms associated with the pathogen.  相似文献   
36.
  1. Detecting rare species is often a necessity for conservation and management, yet challenging for many field survey methods. Environmental DNA (eDNA) is a highly promising solution that has been shown to outperform many established survey methods.
  2. Macquarie perch (Macquaria australasica) is an endangered native species that has declined significantly in range and abundance. Detection of M. australasica was compared with an abundant alien fish species (Oncorhynchus mykiss) using eDNA and three conventional survey methods: gill nets, electrofishing and fyke nets.
  3. eDNA occupancy estimates for both fish species were compared using four different models to investigate what effect these differences have on false positives and false negatives for the rare and common fish species. These models used unadjusted eDNA detections in water samples, eDNA detections that have been screened using a limit of detection method to remove potential false positives, eDNA data supplemented with a second survey method, or eDNA data augmented with sequencing of positive polymerase chain reaction replicates.
  4. eDNA surveying as a single detection method was found to be more efficient and sensitive compared with each capture method separately and combined. Occupancy estimates for the common and rare species did not vary significantly between the four site occupancy-detection models, suggesting that supplementary data may not have as much effect on occupancy estimates compared with other approaches such as temporal or spatial sampling.
  5. We conclude that eDNA outperforms the three established survey methods for both a rare and common freshwater fish species. Although there was no significant effect of augmenting eDNA survey methods with other survey data, additional data may improve confidence in detection, and provide confirmatory evidence for unexpected or new detections of a species.
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37.
38.
Summary Uncooked white rice and cooked white rice were tested as vehicles for the V4 strain of oral Newcastle disease vaccine. The results of feeding experiments were evaluated by the measurement of haemagglutination inhibition antibodies against Newcastle disease virus. Little of the virus applied to uncooked white rice could be recovered, even immediately after mixing, whereas when the virus was applied to cooked white rice most of it could be recovered. In 4 separate experiments, chickens failed to respond serologically to vaccine supplied on uncooked white rice. In all of 4 experiments with cooked white rice, there were serological responses in vaccinated chickens, from 45% to 100% of the chickens developing titres sufficiently high to indicate protection against challenge with virulent virus. Development of haemagglutination inhibition antibodies in some control chickens indicated the ability of the vaccine virus for lateral spread or persistence in the environment.
Vacunacion Oral De Pollos Con La Cepa V4 Del Virus De La Enfermedad De Newcastle Utilizando Como Vehiculo Arroz Blanco Cocinado Y No Cocinado
Resumen Se utilizo arroz blanco sin cocinar y cocinado como vehículo para la vacuna oral con la cepa V4 de la enfermedad de Newcastle. Los resultados de los experimentos fueron evaluados mediante la determinación de los anticuerpos de inhibición-hemaglutinación contra el virus de la enfermedad de Newcastle. Poca cantidad del virus de la enfermedad de Newcastle pudo recuperarse en el arroz crudo, incluso inmediatamente despues de revolverlo, mientras que la mayoría del virus pudo recuperarse del arroz cocinado. En 4 experimentos separados, los pollos no respondieron serológicamente a la vacuna aplicada en arroz blanco crudo. En los 4 experimentos con arroz cocinado, se detectaron respuestas serológicas en los pollos vacunados; 45% a 100% de los pollos desarrollaron títulos suficientes como para resistir la descarga de virus virulento. El desarrollo de anticuerpos de inhibición-hemaglutinación en algunos de los pollos controles indicó la capacidad del virus vacunal para dispersarse lateralmente y persistir en el ambiente.

Vaccination Par Voie Orale De Poulets Avec La Souche V4 Du Virus De La Maladie De Newcastle Avec Comme Support Du Riz Blanc Cuit Et Du Riz Blanc Cru
Résumé Du riz blanc crû et du riz blanc cuit ont été testés en tant que supports de la souche de virus V4 du vaccin contre la maladie de Newcastle. Les résultats de ces expériences d'alimentation ont été évalués par la mesure des anticorps d'inhibition de l'hémagglutination du virus de la maladie de Newcastle.Seule une petite quantité du virus mélangé dans le riz blanc crû a pu être récupérée même immédiatement après le mélange. Par contre la majeur partie du virus a pu être récupérée lorsqu'il s'agissait du riz blanc cuit.Dans 4 expériences séparées, ils n'y avait pas de réponses sérologiques chez les poulets recevant du vaccin ajouté au riz blanc crû. Dans toutes les 4 expériences avec du riz blanc cuit, les réponses sérologiques ont été positives chez les poulets vaccines, 45p. 100 à 100p. 100 des poulets développant des titres suffisamment élevés pour démontrer une protection contre l'épreuve avec du virus virulent. Le développement des anticorps d'inhibition de l'hémagglutination chez quelques poulets témoins a montré la capacité de diffusion latérale ou la persistance dans l'environnement du virus.
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39.
The zebrafish (Danio rerio) is a popular vertebrate model organism used in a wide range of research fields. Mycobacteriosis, caused by Mycobacterium species, is particularly concerning because it is a common disease associated with chronic infections in these fish. Infections are also a source of uncontrolled experimental variance that may influence research results. Live feeds for zebrafish are common and include paramecia (Paramecium caudatum), brine shrimp (Artemia franciscana) and rotifers (Branchionus spp.). Although nutritionally beneficial, live feeds may pose a biosecurity risk. In this study, we investigate transmission of Mycobacterium chelonae and Mycobacterium marinum through these three live feeds. We show that all three live feeds ingest both M. marinum and M. chelonae and can transmit mycobacterial infections to zebrafish. This observation emphasizes the need for live feeds to be included in the consideration of potential biosecurity risks. This study is of importance to other beyond the zebrafish community, including those of additional aquatic models and those using live feeds for other types of aquaculture.  相似文献   
40.
  • 1. Numbering no more than 100 individuals and facing many threats, the geographically isolated Eastern Taiwan Strait population of Indo‐Pacific humpback dolphins (Sousa chinensis) is in peril. The estuarine and coastal waters of central‐western Taiwan have historically provided prime habitat for these dolphins, but environmental conditions today bear little resemblance to what they were in the past.
  • 2. The humpback dolphins must share their habitat with thousands of fishing vessels and numerous factories built upon thousands of hectares of reclaimed land.
  • 3. They are exposed to chemicals and sewage released from adjacent terrestrial activities. Noise and disturbance associated with construction, vessel traffic and military activities are features of everyday life for these animals.
  • 4. Measures to slow the pace of habitat deterioration and reduce the many risks to the dolphins are urgently needed. As one practical step in this direction, this paper describes the habitat needs of these small cetaceans so that decision makers will be better equipped to define ‘priority habitat’ and implement much needed protection measures under the terms of local legislation.
  • 5. The preferred habitat of these dolphins in Taiwan consists of shallow (<30 m), near‐shore marine waters with regular freshwater inputs.
  • 6. For such a small, isolated and threatened population, ‘priority habitat’ should not be limited to areas of particularly intensive dolphin use or high dolphin density, but rather it should encompass the entire area where the animals have been observed (their current ‘habitat’), as well as additional coastal areas with similar bio‐physical features (‘suitable habitat’). Such a precautionary approach is warranted because the loss of only a few individuals could have serious population‐level consequences.
  • 7. While conventional socio‐economic analysis might suggest that implementing protection measures over an area stretching ~350 km north–south along Taiwan's west coast and ~3 km out to sea would be too ‘costly’, the loss of this charismatic species from Taiwan's waters would send a troubling message regarding our collective ability to reconcile human activities with environmental sustainability. Copyright © 2010 John Wiley & Sons, Ltd.
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