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More than 99% of follicles in mammalian ovaries undergo atresia, but the mechanisms regulating the strict selection process are still unclear. Granulosa cell apoptosis is considered the trigger of follicular atresia, which occurs in advance of the death of an oocyte. Cellular FLICE-like inhibitory protein (cFLIP), a homologue of procaspase-8 (also called FLICE), is an intracellular anti-apoptotic protein. It is expressed in granulosa cells of porcine ovaries, where its levels decreases during follicular atresia. We hypothesized that cFLIP regulates granulosa cell apoptosis by acting as a pro-survival factor. In the present study, to further reveal the function of cFLIP in granulosa cells, we examined the anti-apoptotic mechanism of cFLIP using KGN, a human granulosa tumor cell line. Fas-mediated apoptosis was induced by co-treatment with anti-Fas antibody (CH-11), which acts as an agonist of Fas-ligand, and cycloheximide (CHX). When cFLIP was stably expressed in KGN cells following transfection of an expression vector, the Fas-mediated apoptosis was inhibited. Suppression of cFLIP by small interfering RNA (siRNA) spontaneously induced cell death. Silencing of cFLIP promoted cleavage of procaspase-8, and the cell death caused by cFLIP siRNA was completely blocked by a caspase-8 inhibitor (Z-IETD-FMK), indicating that cFLIP regulates apoptosis in KGN cells by inhibiting cleavage of procaspase-8. In conclusion, cFLIP is an essential pro-survival factor for granulosa cells, and it prevents granulosa cell apoptosis by inhibiting procaspase-8 activation.  相似文献   
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Spontaneously Diabetic Torii (SDT) fatty rats, made by introducing the fa allele of the Zucker fatty rat into the SDT rat genome, represent a new model of obese type 2 diabetes. SDT fatty fa/fa (SDT fatty) rats exhibit overt obesity, hyperglycemia, and hyperlipidemia from about six weeks of age, and this is associated with hyperphagia by an induced disorder of leptin action. The present study was conducted to elucidate whether suppression of hyperphagia can improve reduce abnormalities in SDT fatty rats. SDT fatty rats were subjected to pair-feeding with SDT fatty +/ + (SDT) rats from 6 to 26 weeks of age, and the effects on metabolic parameters and diabetic complications were assessed. Body weights of the pair-fed rats were similar with those of SDT rats during the experimental period. Improvement of hyperglycemia or hypertriglyceridemia was observed from 8 to 16 or 12 weeks of age in the pair-fed rats, but hypercholesterolemia was not entirely improved during the experimental period. We also examined mRNAs expression in liver, and found that the expression associated with glyconeogenesis, such as glucose-6-phosphatase (G-6-Pase) and phosphoenolpyruvate carboxykinase (PEPCK), tended to decrease in the pair-fed rats, and the mRNA expression of hydroxymethylglutaryl-CoA (HMG-CoA) was elevated. Renal parameters, such as blood urea nitrogen and urinary albumin excretion, were improved in the pair-fed rats. The incidence or progression of diabetic complications, such as renal lesions and cataract, was reduced. In conclusion, suppression of hyperphagia in SDT fatty rats was effective in temporally improving hyperglycemia or hypertriglyceridemia, and reducing the incidence or progression of diabetic complications, but was ineffective in reducing hypercholesterolemia.  相似文献   
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To obtain basic knowledge about selecting horses for therapeutic riding, the influence of equine conformation on rider oscillation and relationships between these factors and the evaluation on horses as the therapeutic riding were studied. Thirty-five riding horses were used. Equine conformation was estimated by 24 indices. Rider oscillation was measured by an accelerometer fixed at the rider’s waist. The spatial position of the oscillation was estimated by a double integration of the acceleration. Horses were evaluated for therapeutic riding by a Riding for the Disabled Association instructor as a rider. Evaluations were on a scale of 1 to 5, with 5 being the highest score for 27 items. Horses were classified into 4 groups: the short and narrow (SN), short and wide (SW), tall and narrow (TN), and tall and wide (TW). The frequencies of rider oscillation both at walk and trot were higher (P<0.01), and the vertical (P<0.01) and longitudinal (P<0.05) amplitudes at trot were smaller, on short horses than on tall horses. The vertical amplitude at walk was smaller (P<0.05) and the lateral amplitude at trot was larger (P<0.01) on wide horses than on narrow horses. Short horses could be used for the rider who requires side walkers. Wide horses could be used for relieving muscular tension and for the rider who could not maintain good balance on the horse. Short and wide horses should be suitable for therapeutic riding.  相似文献   
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It is known that soil property varies along the slope. It suggests that soil solution chemistry also differs topographically. To determine the variation in soil solution chemistry within one watershed, soil solution chemistry at the different positions of the slope was investigated. Soil N transformation changed along the slope. NH4 + ratio to inorganic N (NH4 + + NO3 ) increased upslope. The tendency was verified by laboratory incubation. After incubation most of the mineralized N was nitrified at the lower part of the slope, while little nitrification occurred at the upper part of the slope. At the ridge and the backslope inorganic N form in soil solution was concomitant with inorganic N form by incubation. At the ridge NH4 + was predominant form in soil solution, at that time major anion was sea salt originated Cl. From this, soil solution chemistry seems to be regulated by the external nutrient source at the ridge. In the second year of lysimeter installation NO3 concentration increased in both sites and the ratio of NH4 + to inorganic N decreased. It was considered due to the effect of lysimeter installation. The lag time and the magnitude of NO3 increase were different between the ridge and the backslope. It would be related with soil N transformation in pre-disturbance. The influence of disturbance were shown in other solute concentrations of soil solution.  相似文献   
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Canine gastroesophageal intussusception (GEI) is a rare and life-threatening condition that requires prompt diagnosis and treatment. A 19-day-old Siberian Husky with a 4-day history of regurgitation was diagnosed with GEI based on the findings of computed tomography (CT) performed without anesthesia. Endoscopic reduction of intussusception was impossible; thus, surgical reduction by traction of the duodenum was performed. CT revealed improvement of megaesophagus 82 days postoperatively. Eleven months postoperatively, fluoroscopy showed recovery to nearly normal esophageal motility. Two years postoperatively, no clinical signs were reported. CT is useful to diagnose GEI in neonate puppies with poor abdominal fat and to assess the gastric edema and the anatomical association of stomach with other organs. Fluoroscopy is helpful for evaluating postoperative esophageal motility.  相似文献   
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Streptomyces spp. are a highly diverse group of bacteria most of which are soil-inhabiting saprophytes. A few are plant pathogens that produce a family of phytotoxins called thaxtomins and cause significant economic losses, e.g., by reducing the marketability of potato tubers (Solanum tuberosum). In northern Europe, S. scabies, S. turgidiscabies and S. europaeiscabiei are the most common plant pathogenic species. In this study, a Streptomyces strain isolated from a netted scab lesion on a tuber of potato cv. Bintje in northern Sweden was identified as S. turgidiscabies but was found to differ in the genomic region carrying genes required for thaxtomin biosynthesis. Our results showed that the strain did not produce thaxtomin but rather phytotoxin fridamycin E, which is an anthraquinone novel to plant pathogenic Streptomyces spp. Fridamycin E was shown to reduce or inhibit sprouting of potato microtubers in vitro. While fridamycin E is known to have antibiotic activity against Gram-positive bacteria, the inhibitory activity of fridamycin E on plant growth is a novel finding.  相似文献   
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