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31.
BRCA1 is a high-penetrance breast cancer susceptibility gene and BRCA1-associated breast cancer has a high familial prevalence that is more common among certain populations of humans. A similar high prevalence also exists for canine mammary tumors (CMTs) and the objective of this study was to determine the breed-related differences in malignant CMTs. Comparative analyses of the expression of various prognostic factors for CMTs, including BRCA1, estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER-2) were conducted on 139 malignant CMT cases from five breeds with the highest prevalence of CMTs in Korea.Significant breed-related differences were observed in the expression of BRCA1 (P = 0.003), histological grade (P = 0.038), and extensive lymphatic invasion (P = 0.042). The Shih Tzu breed had the highest proportion of dogs with malignant CMT and strong overexpression of BRCA1. Cytoplasmic and membranous expression of BRCA1 was associated with the ER negative (P = 0.004), PR negative (P = 0.046), and triple negative (ER, PR, and HER-2 negative; P = 0.016) phenotype and the basal-like molecular subtype (P = 0.019) in Shih Tzu dogs. Since these features are similar to BRCA1-related human breast cancer, dogs with BRCA1-associated CMT, particularly Shih Tzu dogs, may serve as a suitable spontaneous model, although additional molecular studies are needed.  相似文献   
32.
A six-year-old intact female Maltese dog weighing 3.8 kg presented with a history of mild lameness and swelling on both forelimbs. Radiographic and computed tomographic views revealed an extensive periosteal reaction in all four limbs and a large round mass on the right middle lung lobe. A total lobectomy was performed and pulmonary adenosquamous carcinoma was histologically confirmed. A diagnosis of hypertrophic osteopathy (HO) secondary to a lung tumor was made. Periosteal proliferation decreased significantly after surgery; however, there was evidence of dyspnea, mass recurrence, and periosteal reaction three months post-operatively. This is the first case report of pulmonary adenosquamous carcinoma with HO in a dog in which we describe clinical, imaging, surgical, and histological findings.  相似文献   
33.
The pathogenesis of porcine reproductive and respiratory syndrome virus (PRRSV) infection in ovary was studied in sexually mature, cycling, nonsynchronized gilts infected with the PRRSV 16244B, a virulent field strain. Previous studies have shown that PRRSV can be isolated from ovaries and is transplacentally passed from gilts to the fetuses. The cause of infertility following PRRSV infection is not known. In this study, we identified the tropism of PRRSV in ovarian tissue from experimentally infected gilts in samples collected between 7 and 21 days postinfection (DPI). Tissues were collected and examined by virus isolation, in situ hybridization (ISH), immunohistochemistry (IHC), and double labeling to identify PRRSV-infected cell types. PRRSV was isolated in ovarian follicles at 7 days DPI. The IHC and ISH indicated that PRRSV-positive cells in ovaries were predominantly macrophages, which were numerous in atretic follicles. No evidence of infection and/or perpetuation of PRRSV in ova was observed, indicating that the female gonad is an unlikely site of persistence. No alteration of the normal ovarian architecture that would support a possible role of PRRSV infection in porcine female infertility was observed.  相似文献   
34.
This study examines apoptosis and viral neuropathogenesis in a murine model infected with vesicular stomatitis virus (VSV). VSV induces apoptotic cell death in cultured cell lines, raising the possibility that apoptosis of infected neurons and other target cells may contribute to disease and mortality. To determine whether or not VSV induces apoptosis in neural tissues, mice were inoculated intranasally with VSV. At 24, 48, 72, 96, and 120 hours postinfection, brain tissues were assayed for the presence of viral RNA by in situ hybridization and viral antigen by immunohistochemistry. Apoptosis was identified by in situ terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling and electron microscopy. Viral replication and lesions were observed predominantly in central nervous system neurons. Apoptotic cell death was restricted to the same regions of the brain in which infected cells and tissue injury were identified. Results suggest that VSV-induced apoptosis is a mechanism causing cell death, tissue injury, and mortality in VSV-infected mice.  相似文献   
35.
The purpose of this study was to identify time-related changes in clinical, MRI, histopathologic, and immunohistochemical findings associated with ischemic stroke in dogs. Additionally, the association of cerebrospinal fluid (CSF) and tissue levels of interleukin (IL)-6 with clinical prognosis was assessed. Ischemic stroke was induced by permanent middle cerebral artery occlusion (MCAO) in nine healthy experimental dogs. The dogs were divided into three groups according to survival time and duration of the experimental period: group A (survived only 1 day), group B (1-week experimental period), and group C (2-week experimental period). Neurologic status was evaluated daily. Magnetic resonance imaging (MRI) was performed according to a predetermined schedule. Concentration of IL-6 in CSF was measured serially after ischemic stroke. Postmortem examination was performed for all experimental dogs. During histopathological examination, variable degrees of cavitation and necrosis due to neuronal cytopathic effects, such as pyknotic nuclei and cytoplasmic shrinkage, were observed on the affected side of the cerebral cortex in all dogs. Immunohistochemistry specific for IL-6 showed increased expression in the ischemic lesions. CSF IL-6 concentrations and ischemic lesion volumes 1 day after ischemic stroke were significantly higher in group A compared to groups B and C.  相似文献   
36.
The photodegradation of aqueous alcoholic solutions of fenarimol at λ ≥ 250 nm has been examined. UV irradiation of an aqueous methanolic solution for 24 h yielded two photoproducts, identified as 2,4′‐dichlorobenzil and p‐chlorobenzoic acid, while irradiation of a solution in aqueous isopropanol yielded p‐chlorobenzoic acid and two additional products identified as 2,4′‐dichlorobenzophenone and o‐chlorobenzoic acid. A mechanism for the formation of the photoproducts is suggested. © 2000 Society of Chemical Industry  相似文献   
37.
Hypothermia is directly linked to metabolism; however, it is still unknown how the overall metabolism is altered by oral administration of hypothermic agent, l -citrulline (l -Cit). The present study aimed to determine the characteristics of liver metabolites of chicks orally administered l -Cit to provide a greater understanding of its metabolism. Capillary electrophoresis–time-of-flight mass spectrometry (CE-TOFMS) and liquid chromatography–time-of-flight mass spectrometry (LC-TOFMS) were conducted on liver samples after oral administration of l -Cit. A total of 361 liver metabolites were identified. Although a small number of samples were used for each group, a principal component analysis and heatmap patterns confirmed that the composition of metabolites could be segregated from each other. Of the 361 compounds detected in the liver, 41 compounds, including amino acids related to the Cit-arginine (Arg) cycle, argininosuccinic acid, Arg, ornithine, and Cit, as well as gamma aminobutyric acid, glycine, histidine, and nicotinamide adenine dinucleotide were abundant in l -Cit-treated livers. In contrast, 24 compounds containing fatty acids, amino acids, and cyclic adenosine monophosphate were lower in the l -Cit group. These data imply that the active Cit-Arg cycle, TCA cycle metabolism, and a low activity in fatty acid metabolism occur in l -Cit-treated broiler chicks.  相似文献   
38.
Sound and sprouted flours (24 and 48 hr) from bread wheat (WL-1562), durum wheat (PBW-34) and triticale (TL-1210) were stored at room temperature (34.8°C) and relative humidity (66.7%) for 0, 45, 90 and 135 days to assess the changes in physico-chemical and baking properties. Protein, gluten, sedimentation value, starch and crude fat decreased during storage in all the samples; however, the decrease was more in sprouted flours. Free amino acids, proteolytic activity, diastatic activity and damaged starch decreased with increase in storage period. Total sugars and free fatty acids increased more rapidly in the flours of sprouted wheats during 135 days of storage. Loaf volume of breads decreased during storage in both sound and sprouted flour but the mean percent decrease in loaf volume was more in stored sound flours. Aging of sprouted flour for 45 days improved the cookie and cake making properties but further storage was of no value for these baked products.Chapati making properties of stored sound and sprouted flour were inferior to that of fresh counterparts.  相似文献   
39.
40.
Latent infection with bovine herpesvirus type-5 (BHV-5) was established in rabbits inoculated with two South American isolates (EVI-88 and 613) by intranasal or conjunctival routes. Nine rabbits (613, 8/27; EVI-88, 1/34) developed neurological disease and died during acute infection and other three (613, n=2; EVI-88, n=1) developed a delayed neurological disease, at days 34, 41 and 56 post-inoculation (p.i.). Between days 56 and 62 p.i., the remaining rabbits were submitted to five daily administrations of dexamethasone (Dx) to reactivate the infection. Twenty-five out of 44 rabbits (56.8%) shed virus in nasal or ocular secretions after Dx treatment. Virus shedding was first detected at day two post-Dx and lasted from one to 11 days. The highest frequencies of virus reactivation were observed in rabbits inoculated conjunctivally (10/15 versus 15/29); and among rabbits infected with isolate 613 (12/16 versus 13/28). Virus reactivation upon Dx treatment was accompanied by neurological disease in nine rabbits (20.4%), resulting in six deaths (13.6%). Virus in moderate titers and mild to moderate non-suppurative inflammatory changes in the brain characterized the neurological infection. Three other rabbits showed severe neurological signs followed by death after 31 to 54 days of Dx treatment. Virus, viral nucleic acids and inflammatory changes were detected in their brains. The late-onset neurological disease, after acute infection or Dx treatment, was probably a consequence of spontaneous virus reactivation. These results demonstrate that BHV-5 does establish a latent infection in rabbits and that clinical recrudescence may occur upon reactivation.  相似文献   
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