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101.
Although the beta2 adrenergic agonists have been seen to have important effects on the mechanisms regulating the development and death of T-cells in the thymus, the side-effects on the immune system of anabolic treatments of these substances have hardly been considered. In order to evaluate the effects exerted by the beta2 adrenergic agonist clenbuterol on the thymocyte population, the thymus of eight pigs treated with anabolic doses of this substance was studied by morphometric methods, regarding apoptotic (terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling (TUNEL)-positive) and normal (TUNEL-negative) cells. The thymus of another eight pigs fed without clenbuterol served as a control. The clenbuterol treatment had a clear effect on the thymocyte size, decreasing their mean nuclear area. The T-cell apoptosis index was also affected by the clenbuterol, significantly increasing the apoptosis percentage in the treated group with respect to the control. In the light of our results, the clenbuterol induced thymocyte apoptosis throughout the thymus and caused morphometric changes in the thymocyte population, which was in line with the immunosuppressive role attributed to other beta2 adrenergic agonists.  相似文献   
102.
Herpes simplex virus-1 (HSV-1) based amplicon vectors are promising gene delivery vehicles because they have a large transgene capacity and can efficiently transduce many different cell types, including non-dividing cells, of various animal species. The Circ protein of bovine herpesvirus-1 (BHV-1) is a myristylated virion component of unknown function. Preliminary experiments with a circ gene deletion mutant indicated that Circ may influence the host's immune response by downregulating MHC-II expression in bovine monocytes. To get more insight into the function of Circ, amplicon vectors were constructed with various open reading frames (ORFs) under the control of the HSV-1 IE4/5 promoter: (i) the Circ ORF alone, (ii) a fusion ORF encoding an N-terminal Circ fused to the enhanced green fluorescent protein (eGFP), (iii) the eGFP ORF alone, and (iv) the Circ ORF in the inverted orientation. Upon helpervirus-free packaging into HSV-1 amplicon particles and transduction of Vero cells, both Circ alone and the Circ-eGFP fusion protein produced a punctate pattern within the cytoplasm, suggesting membrane association of the myristylated protein. In contrast, eGFP alone was evenly distributed over the cytoplasm of transduced cells. Upon infection of bovine buffy-coat cells, it was observed that cells of the monocyte lineage but not lymphocytes were transduced. Transgene expression reached a peak around 20h after transduction and lasted for at least 90h. Transduced monocytes underwent specific morphological changes, which may be attributed to Circ synthesis.  相似文献   
103.
A total of 207 teeth belonging to 53 deer (Cervus elaphus hispanicus) from Sierra Morena (South of Spain) were analysed using histological thin sections and/or polished thick sections. Growth marks were observed in dentine and cementum of incisors, molars and canines. Tooth, region of the tooth, and type of preparation giving the best performance in terms of sharpness and interpretation ease of the growth marks, when used for Spanish deer ageing, were identified. The tissue chosen for the study was the cellular cementum of the inter-radicular pad from molars and the acellular cementum of the root from incisors, both observed through longitudinal cuts. Histological sections obtained with a conventional microtome were optimal for a reliable identification of the first growth marks. In sections thicker than 15 microm the first rest line, when observed in cementum can be confused with the cementum-dentine junction; whereas in the polished sections from molars it will not appear at all. Dentine interpretation was more difficult. Its observation should only be accomplished using cross-sections of the molar root. Secondary or accessory marks were visible in every tooth, being those from the molar pad the easiest to distinguish. Canines were the less suitable teeth for this study.  相似文献   
104.
105.
The potential cytotoxic effects of the compounds 8-quinolinol, chloramine-T and natamycin have been studied in isolated pig hepatocytes. The relative cytotoxicity of these compounds was evaluated on the basis of the leakage of cytosolic lactate dehydrogenase (LDH), 3-(4,5 dimethyl)thiazol-2-yl,-2,5-diphenyl tetrazolium bromide (MTT) reduction by mitochondrial dehydrogenases, uptake of neutral red (NR) by cytosolic lysosomes, glutathion (GSH) depletion and oxidized glutathion (GSSG) efflux after 24 h exposure. Evaluation of the 20%, 50% and 80% reduced absorbance data obtained from the parameters NR20, NR50, and NR80, and MTT20, MTT50 and MTT80 enabled us to rank these compounds in decreasing order of cytotoxicity: 8-quinolinol > natamycin > chloramine-T. Also for the parameters LDH and GSH, chloramine-T appears to be less cytotoxic than natamycin and 8-quinolinol. Our study demonstrated that pig hepatocytes may be a useful model for examining cytotoxic events of drugs to be used in pigs, therefore avoiding possible extrapolation problems due to species differences.  相似文献   
106.
The Chato Murciano pig is a breed catalogued as a Special Protection breed in danger of extinction. At present it is commonly reared in an intensive system. We have studied the mineral composition and other characteristics of its carcass and meat. Samples from the Musculus longissimus lumborum were taken from a total number of 43 animals, divided into two groups, Chato Murciano and Chato Murciano crossed with Iberian, reared in a conventional indoor system. The resulting meat of the Chato Murciano pig and its cross with Iberian was especially rich in iron and copper, rich in phosphorus, and marginally poor in calcium and sodium. The evolution of the pH of the carcass was that of pigs which do not produce PSE (pale, soft and exudative) meat. Some relevant positive correlation coefficients between minerals (P ≤ 0.05) have been found.  相似文献   
107.
Santiago, Chile's semi-arid climate and urbanized environment poses a severe limitation for the establishment and maintenance of urban forests. Municipalities, or comunas, are the main stakeholders in the management of Santiago's public urban forests. A tenable hypothesis would be that as the socioeconomic level of a comuna increases, the better the condition of a comuna's urban forest. Unfortunately, there is little comprehensive information on management, public expenditure, and structure of Santiago's public and private urban forests. To examine this hypothesis, Santiago was divided into socioeconomic strata, then using air photo interpretation and stratified field sampling, urban forest structures were quantified by socioeconomic strata. In addition, interview surveys were used to determine municipal urban forest management and expenditures for different public urban forests based on socioeconomic strata. Urban forests in the high socioeconomic strata had fewer public trees, greater tree cover, tree and leaf area density, and leaf area index than lower socioeconomic strata. The percentage of total municipal budget allocated to public urban forest management was consistent among strata, but the total public urban forest budgets were greater in the high socioeconomic strata. Public urban forest structure is related to the socioeconomic strata of Santiago's different comunas.  相似文献   
108.
ABSTRACT Unmodified and low water activity (a(w))-tolerant cells of Candida sake CPA-1 applied before harvest were compared for ability to control blue mold of apples ('Golden Delicious') caused by Penicillium expansum under commercial storage conditions. The population dynamics of strain CPA-1 on apples were studied in the orchard and during storage following application of 3 x 10(6) CFU/ml of each treatment 2 days prior to harvest. In the field, the population size of the unmodified treatment remained relatively unchanged, while the population size of the low-a(w)-modified CPA-1 cells increased. During cold storage, the populations in both treatments increased from 10(3) to 10(5) CFU/g of apple after 30 days, and then declined to about 2.5 x 10(4) CFU/g of apple. In laboratory studies, the low-a(w)-tolerant cells provided significantly better disease control as compared with the unmodified cells and reduced the number of infected wounds and lesion size by 75 and 90%, respectively, as compared with the non-treated controls. After 4 months in cold storage, both unmodified and low-a(w)-tolerant cells of C. sake were equally effective against P. expansum on apple (>50% reduction in size of infected wounds).  相似文献   
109.
Cranberry (Vaccinium macrocarpon) products have been widely recommended in traditional American medicine for the treatment of urinary tract infection (UTI). A total of 19 different commercial cranberry products from American and European markets have been analyzed by different global phenolic methods and by UPLC-DAD-ESI-TQ MS. In addition, in vitro antioxidant capacity and uropathogenic bacterial antiadhesion activity tests have been performed. Results revealed that products found in the market widely differed in their phenolic content and distribution, including products completely devoid of flavan-3-ols to highly purified ones, either in A-type proanthocyanidins (PACs) or in anthocyanins. The product presentation form and polyphenolic profile widely affected the antiadhesion activity, ranging from a negative (nulel) effect to a MIC = 0.5 mg/mL for cranberry powders and a MIC=112 mg/mL for gel capsule samples. Only 4 of 19 products would provide the recommended dose of intake of 36 mg total PACs/day. Of most importance was the fact that this dose would actually provide as low as 0.00 and up to 205 μg/g of procyanidin A2, indicating the lack of product standardization and incongruence between global and individual compound analysis.  相似文献   
110.
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