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991.
This study evaluated the protective effects of purple rice ( Oryza sativa L.) bran extract (PRE) and its major anthocyanidins (cyanidin and peonidin) against light-induced retinal damage. In an in vitro experiment, cultured murine photoreceptor cells (661W) were damaged by a 24 h exposure to light. Viability of 661W after light treatment, assessed by the tetrazolium salt (WST-8) assay and Hoechst 33342 nuclear staining, was improved by the addition of PRE, cyanidin, and peonidin. Intracellular radical activation in 661W, evaluated using the reactive oxygen species (ROS) sensitive probe 5-(and 6)-chloromethyl-2,7-dichlorodihydrofluorescein diacetate acetyl ester (CM-H(2)DCFDA), was reduced by PRE and its anthocyanidins. Electron spin resonance (ESR) measurements showed that PRE, peonidin, and cyanidin all exhibited radical scavenging activities against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, superoxide anion radical ((?)O(2)(-)), and hydroxyl radical ((?)OH). In an in vivo mouse experiment, intravitreous injection of PRE significantly suppressed photoreceptor degeneration induced by exposure to light as revealed by histological analysis using hematoxylin-eosin staining. These findings suggest that PRE and its anthocyanidins possess protective effects with antioxidation mechanism in both in vitro and in vivo models of retinal diseases.  相似文献   
992.
A two-year-old dog having presented with neurological signs showed marked leukocytosis and appearance of blast cells in the peripheral blood. Hematological and bone marrow examination showed an increase in blasts having both myeloid and monocytic cells characteristics. The dog was diagnosed with acute myelomonocytic leukemia (AML-M4) on the basis of bone marrow findings. Although the dog was treated with a multi-combination chemotherapy, the neurological abnormalities progressed and the dog was euthanized. Myelographic examination and necropsy revealed the extradural lesion formed by AML-M4 around the cervical spinal cord and this lesion was considered as a cause of the neurological signs.  相似文献   
993.
The Sry (sex determining region on Y chromosome) gene is a master gene for sex determination. We previously reported that the Sry gene has tissue-dependent and differentially methylated regions (T-DMRs) by analyzing the DNA methylation states at CpG sites in the promoter regions. In this study, we found unique non-CpG methylation at the internal cytosine in the 5'-CCTGG-3' pentanucleotide sequence in the Sry T-DMR. This non-CpG methylation was detected in four mouse strains (ICR, BALB/c, DBA2 and C3H), but not in two strains (C57BL/6 and 129S1), suggesting that the CCTGG methylation is tentative and unstable. Interestingly, this CCTGG methylation was associated with demethylation of the CpG sites in the Sry T-DMR in the developmental process. A methylation-mediated promoter assay showed that the CCTGG methylation promotes gene expression. Our finding shows that non-CpG methylation has unique characteristic and is still conserved in mammals.  相似文献   
994.
Aquaporins (AQPs) function as water channels in many types of cells involved in fluid transport. More than 10 isoforms have been identified, and these are differentially expressed in many types of mammalian cells in the body. Six AQPs (AQP0, AQP1, AQP3, AQP4, AQP5, and AQP9) have been identified in the eyes of humans and/or rodents. The unique permeability characteristics and distribution of AQPs indicate their diverse roles in the regulation of water homeostasis in the eye. The aim of this study was to investigate the localisation of AQPs in normal canine eyes, with AQP0 protein expressed in the crystalline lens and retina. Although AQP1 mRNA was detected in various areas of the canine eye, its protein expression was limited to the cornea, iris and ciliary body. AQP4 was identified in the iris, retina and optic nerve. AQP3 and AQP5 were found in the cornea and conjunctiva, and their expression was particularly high in the limbus. AQP3 and AQP5 were present in the nictitating membrane indicating that they play a role in water transport within the membrane. The observations suggested that several subtypes of the AQP family are involved in the regulation of water homeostasis in the canine eye.  相似文献   
995.
BACKGROUND: Quinoxyfen is a fungicide of the phenoxyquinoline class used to control powdery mildew, Uncinula necator (Schw.) Burr. Owing to its high persistence and strong sorption in soil, it could represent a risk for soil organisms if they are exposed at ecologically relevant concentrations. The objective of this paper is to predict the bioconcentration factors (BCFs) of quinoxyfen in earthworms, selected as a representative soil organism, and to assess the uncertainty in the estimation of this parameter. Three fields in each of four vineyards in southern and northern Italy were sampled over two successive years. RESULTS: The measured BCFs varied over time, possibly owing to seasonal changes and the consequent changes in behaviour and ecology of earthworms. Quinoxyfen did not accumulate in soil, as the mean soil concentrations at the end of the 2 year monitoring period ranged from 9.16 to 16.0 µg kg?1 dw for the Verona province and from 23.9 to 37.5 µg kg?1 dw for the Taranto province, with up to eight applications per season. To assess the uncertainty of the BCF in earthworms, a probabilistic approach was used, firstly by building with weighted bootstrapping techniques a generic probabilistic density function (PDF) accounting for variability and incompleteness of knowledge. The generic PDF was then used to derive prior distribution functions, which, by application of Bayes' theorem, were updated with the new measurements and a posterior distribution was finally created. CONCLUSION: The study is a good example of probabilistic risk assessment. The means of mean and SD posterior estimates of log BCFworm (2.06, 0.91) are the ‘best estimate values’. Further risk assessment of quinoxyfen and other phenoxyquinoline fungicides and realistic representative scenarios for modelling exercises required for future authorization and post‐authorization requirements can now use this value as input. Copyright © 2011 Society of Chemical Industry  相似文献   
996.
We investigated the effects of the oral administration of lophenol (Lo) and cycloartanol (Cy), two kinds of antidiabetic phytosterol isolated from Aloe vera , on glucose and lipid metabolism in Zucker diabetic fatty (ZDF) rats. We demonstrated that the administrations of Lo and Cy suppressed random and fasting glucose levels and reduced visceral fat weights significantly. It was also observed that treatments with Lo and Cy decreased serum and hepatic lipid concentrations (triglyceride, nonesterified fatty acid, and total cholesterol). Additionally, Lo and Cy treatments resulted in a tendency for reduction in serum monocyte chemotactic protein-1 (MCP-1) level and an elevation in serum adiponectin level. Furthermore, the expression levels of hepatic genes encoding gluconeogenic enzymes (G6 Pase, PEPCK), lipogenic enzymes (ACC, FAS), and SREBP-1 were decreased significantly by the administrations of aloe sterols. In contrast, Lo and Cy administration increased mRNA levels of glycolysis enzyme (GK) in the liver. It was also observed that the hepatic β-oxidation enzymes (ACO, CPT1) and PPARα expressions tended to increase in the livers of the Lo- and Cy-treated rats compared with those in ZDF-control rats. We therefore conclude that orally ingested aloe sterols altered the expressions of genes related to glucose and lipid metabolism, and ameliorated obesity-associated metabolic disorders in ZDF rats. These findings suggest that aloe sterols could be beneficial in preventing and improving metabolic disorders with obesity and diabetes in rats.  相似文献   
997.
The potential of invasive plants to alter fuel properties over time has implications for the ranchers of semiarid rangelands throughout the world. A prime example of this phenomenon is the cheatgrass (Bromus tectorum L.) invasion of the native shrub-steppe lands in Great Basin of the western United States. The purpose of this study is to develop a bioeconomic model that optimizes simulated ranch behavior given the beginning stages of cheatgrass invasion on a public forage allotment. The bioeconomic model is applied to a typical eastern Oregon 300 cow-calf ranch. Livestock production decisions are simulated over a 40-yr planning horizon using a multiperiod linear programming model. Results showed changes in profit-maximizing ranch management strategies in the form of decreased optimal stocking rates and forage substitution. The net present value of the simulated ranch’s income stream declined, and the probability that the ranch cannot meet its full costs of livestock production and would exit the industry increased as a result. These economic impacts were more pronounced with decreased sale price. Sensitivity analysis showed that overall results in terms of ranch behavior were specific neither to the assumed discount rate nor to the assumed percentage of cheatgrass cover (as long as this percentage is within the reference state) on the public grazing allotment. This study introduces a method for managers to quantify impacts on ranches from fuel-altering invasive plants on public lands, emphasizing the importance of including information about native and invasive forage production characteristics and wildfire frequency as a function of the state of invasion.  相似文献   
998.
999.
Mast cell tumours are one of the most common neoplasms in dogs. Mutations in the proto‐oncogene c‐kit, especially internal tandem duplications of exon 11, are considered to play a crucial role in mast cell tumourigenesis. In this report, two cases that suffered from multiple mast cell tumours containing an internal tandem duplication in the primary lesion but not in the secondary lesions are described. This finding indicates the existence of heterogenous c‐kit gene mutations in each site of multiple mast cell tumours. Additionally, these results raise the possibility that the contribution of internal tandem duplications in the malignant transformation of mast cells is quite limited. It is proposed that, for clinicians, genetic analysis of several regions of multiple mast cell tumours is necessary for predicting prognosis and tumour response to KIT inhibitors.  相似文献   
1000.
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