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1.
A. B. De Nardi C. R. Daleck C. H. M. Souza R. L. Amorin S. Rodaski C. Calderon R. Torres 《Veterinary and comparative oncology》2005,3(1):56-57
Introduction: Cyclooxygenase‐2 (Cox‐2) is the inducible form and the rate‐limiting enzyme, for conversion of arachidonic acid to prostaglandins. Cox‐2 overexpression, common in carcinomas, is associated with increased growth rate, resistance to apoptosis, angiogenesis, and overall, both local and distant aggressive behavior. Cox‐2 overexpression has been detected in human and canine mammary tumors (MTs). Histopathology of canine MT is not always predictive of biologic behavior, and anecdotally, only 50% of the malignant MTs are expected to metastasize. We hypothesize that Cox‐2 expression correlates with aggressive behavior.
Methods: This retrospective study evaluated 48 bitches, presented for excision of MT between 2000 and 2003 at FMVZ de Botucatu‐UNESP, Brasil. Follow‐up varied from 18 months to 24 months and included physical examination and thoracic radiographs. Histopathologic examination was performed in all tumors, as well as in metastatic lesions when detected in the follow‐up period. Immunohistochemistry was used to detect expression of Cox‐2 in paraffin blocks (Rabbit polyclonal anti‐PGHS‐2. Oxford Biomedical). 10 adenomas, 10 carcinomas, 10 benign mixed tumors, 10 malignant mixed tumors and 8 cases of primary carcinomas and their metastatic lesions.
Results: Expression of Cox‐2 varied among groups. Adenomas (32.1%), mixed benign tumors (38%), carcinomas (60.3%), malignant mixed tumors (65.8%), and metastatic carcinomas (81.25%) and their metastatic lesions (84.35%). Statistically significant differences (p < 0.05) were observed between the benign and malignant counterparts and between carcinomas and metastatic carcinomas.
Conclusions: Cox‐2 expression correlates with both histologic and biologic behavior in mammary carcinomas, and may serve as a predictor of metastatic potential. 相似文献
Methods: This retrospective study evaluated 48 bitches, presented for excision of MT between 2000 and 2003 at FMVZ de Botucatu‐UNESP, Brasil. Follow‐up varied from 18 months to 24 months and included physical examination and thoracic radiographs. Histopathologic examination was performed in all tumors, as well as in metastatic lesions when detected in the follow‐up period. Immunohistochemistry was used to detect expression of Cox‐2 in paraffin blocks (Rabbit polyclonal anti‐PGHS‐2. Oxford Biomedical). 10 adenomas, 10 carcinomas, 10 benign mixed tumors, 10 malignant mixed tumors and 8 cases of primary carcinomas and their metastatic lesions.
Results: Expression of Cox‐2 varied among groups. Adenomas (32.1%), mixed benign tumors (38%), carcinomas (60.3%), malignant mixed tumors (65.8%), and metastatic carcinomas (81.25%) and their metastatic lesions (84.35%). Statistically significant differences (p < 0.05) were observed between the benign and malignant counterparts and between carcinomas and metastatic carcinomas.
Conclusions: Cox‐2 expression correlates with both histologic and biologic behavior in mammary carcinomas, and may serve as a predictor of metastatic potential. 相似文献
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The purpose of this study was to determine the percentage of dogs with spontaneous atopic dermatitis that show a positive patch test reaction to a commercially available 20% house dust mites mixture containing equal parts of Dermatophagoides farinae and Dermatophagoides pteronyssinus in white petrolatum. In addition, we evaluated whether skin reactions induced after the epicutaneous application of house dust mites were clinically and histologically similar to naturally developed skin lesions of dogs with atopic dermatitis. Furthermore, we investigated if the reactions induced by house dust mites were true allergic reactions by comparing them to atopic lesional skin and to patch test reactions induced by an irritant substance (sodium lauryl sulphate). White petrolatum alone and nonlesional skin sites were used as negative controls. Macroscopic and microscopic evaluations of the patch test and control sites were performed in a blinded fashion at 48 and 72 h after patch test application. Microscopic results were evaluated in a qualitative and quantitative manner. A chi‐square test for homogenicity was used for the quantitative analysis to compare the proportion of each dermal inflammatory cell type among positive histopathological tested sites. P values ≤ 0.05 were considered significant. The study included 12 healthy nonatopic dogs and 13 dogs with nonseasonal atopic dermatitis. None of the nonatopic dogs reacted to house dust mites and white petrolatum. Ten (77%) of the 13 atopic dogs reacted macroscopically and histopathologically to house dust mites. Macroscopic reactions induced by house dust mites were characterized by erythema, oedema and papules. The macroscopic reactions induced by house dust mites were identical to lesional skin in 20% of the dogs and identical to reactions induced by sodium lauryl sulphate in 40% of the dogs. Qualitative histopathological findings showed that the reactions induced by house dust mites were similar to atopic lesional skin in 80% of the dogs and were similar to sodium lauryl sulphate in 20% of the dogs. Quantitative analyses showed that the proportion of neutrophils in reactions induced by sodium lauryl sulphate was significantly higher (P < 0.05) compared to house dust mites reactions, which could be a differentiator factor between an allergic and an irritant reaction. These results showed that the epicutaneous application of house dust mites in dogs with atopic dermatitis induced histopathological lesions similar to spontaneous atopic lesions in dogs. Therefore, this study demonstrated that house dust mites penetrated the skin of dogs with atopic dermatitis and induced an inflammatory response that resembled a true allergic reaction. Funding: Small Companion Animal Grant, University of Minnesota. 相似文献
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Paixão Sonália Ferreira Fritzen Juliana Torres Tomazi Crespo Sarah Elizabeth Izzo de Moraes Pereira Helder Alfieri Alice Fernandes Alfieri Amauri Alcindo 《Tropical animal health and production》2018,50(8):1947-1950
Tropical Animal Health and Production - Serological studies have characterized the presence of the bovine viral diarrhea virus (BVDV) infection in water buffalo herds worldwide. However, the... 相似文献
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Maribel Abadias Isabel Alegre Josep Usall Rosario Torres Inmaculada Viñas 《Postharvest Biology and Technology》2011,59(3):289-297
The risk of undesirable by-products from chlorine disinfection in fresh-cut industries, together with its limited efficacy, has led to a search for alternative agents. The aim of this study was to test several alternative putative antimicrobial substances to reduce Escherichia coli O157:H7, Salmonella spp. and Listeria spp. populations on fresh-cut apple. Carvacrol, vanillin, peroxyacetic acid, hydrogen peroxide, N-acetyl-l-cysteine and Citrox were selected for their results in in vitro assays against E. coli O157:H7 and Listeria spp., to be tested on fresh-cut apple plugs. Apple flesh was inoculated by dipping in a suspension of a mix of the studied pathogens at 106 cfu mL?1, and then treated with the antimicrobial substances. All treatments were compared to deionized water and a standard sodium hypochlorite treatment (SH, 100 mg L?1, pH 6.5). Pathogen population on apple plugs was monitored for up to 6 days at 10 °C. Bacterial reductions obtained by peroxyacetic acid (80 and 120 mg L?1), vanillin (12 g L?1), hydrogen peroxide (5, 10, 20 mL L?1) and N-acetyl-l-cysteine (5 and 10 g L?1) were similar or higher than reduction obtained by SH. In addition, bacterial populations were maintained at low levels throughout storage. No cells of any of the pathogens were detected in the peroxyacetic acid, hydrogen peroxide, Citrox and SH washing solutions after apple treatment. Peroxyacetic acid, hydrogen peroxide and N-acetyl-l-cysteine could be potential disinfectants for the fresh-cut industry as an alternative to chlorine disinfection. However, their effect on sensory quality and effectiveness under commercial processing conditions should be evaluated. 相似文献
6.
Enrique Corts‐Ceballos Esther Prez‐Carrillo Sergio O. Serna‐Saldívar 《Cereal Chemistry》2015,92(1):88-92
Double mashing for wort production is a time‐consuming process that can be reduced if pregelatinized adjuncts are used. Optimal extruding conditions were determined to obtain brewing adjuncts from corn and sorghum starch. For corn starch extrusion, a Box–Behnken design was devised in which moisture, screw speed, temperature of the barrel, and concentrations of sodium stearoyl lactylate (SSL) were varied, and sorghum starch was extruded according to a 23 model in which the modified variables were moisture, SSL concentration, and temperature. The aim was to maximize starch damage and minimize resistant starch and final viscosity as determined with a Rapid Visco Analyzer. The treatments that satisfied these requirements were mashed, and wort extract yield was determined. Glucose, maltose, and maltotriose concentrations in the resulting worts were determined by HPLC with a refractive index detector. Feedstock tempering and SSL content were the most important factors affecting the response; for corn starch, treatments with lower moisture (20%) and middle levels of SSL (0.5%) or with high levels of both moisture (40%) and SSL (1%) produced the most desirable samples for mashing, whereas for sorghum starch the best treatment was tempering to 20% moisture and containing middle levels of SSL (0.5%). No statistical differences were found between these experimental treatments and the control. 相似文献
7.
Microdialysis measurements of equine lamellar perfusion and energy metabolism in response to physical and pharmacological manipulations of blood flow 下载免费PDF全文
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