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921.
Real-time PCR was optimized for the quantification of canine CD56 mRNA expression. This study was conducted to easily quantify canine CD56 expression and to identify its expression in normal tissues, peripheral blood mononuclear cells and activated lymphocytes in dogs. This assay revealed the highest level of CD56 mRNA expression in the normal canine brain, followed by the lung, kidney and liver. CD56 mRNA expression level in peripheral blood mononuclear cells was considerably lower; among activated lymphocytes in vitro, CD56 mRNA expression was increased.  相似文献   
922.
To investigate in vitro differentiation of canine adipose tissue-derived stromal cells (ATSCs) into neuronal cells, ATSCs from celiac adipose tissue in clinically healthy beagle dogs were treated with 100 muM dibutyryl cyclic adenosine monophosphate (dbcAMP) and 125 muM isobuthylmethylxanthine (IBMX). ATSCs were morphologically changed into differentiated ATSCs from spindle-shaped cells to neuron-like cells with numerous processes after the treatment. Expression of neuron-specific enolase (NSE) as an early neuron specific marker protein was detected in both ATSCs and differentiated ATSCs, however diachronic increase of NSE expression was observed in differentiated ATSCs after the treatment with dbcAMP/IBMX. In addition, neurofilament-68 (NF-68) as an early to mature neuron specific marker protein was weakly expressed in differentiated ATSCs. Neuron specific glutamate and glucose transporter (EAAC1 and GLUT-3, respectively) mRNAs were strongly expressed in differentiated ATSCs compared with those in ATSCs, although glia specific glutamate transporter mRNA (GLT-1) was also detected in differentiated ATSCs. ATSCs can differentiate into early to mature neuronal cells and are candidate cells for autologous nerve regeneration therapy, although additional research is needed to examine functional characteristics of differentiated ATSCs.  相似文献   
923.
Two neuropeptides, neuropeptide B (NPB) and prolactin-releasing peptide (PrRP), have been suggested to play important roles in control of the hypothalamic-pituitary-adrenal (HPA) axis in rodents. The aim of the present study was to clarify the central actions of NPB or PrRP in sheep. Ovariectomized ewes were surgically implanted with a cannula directed to the lateral ventricle. They received intracerebroventricular (icv) administration of 400 mul of artificial cerebrospinal fluid, NPB (0.05, 0.5 or 5 nmol), PrRP (0.5, 5 or 50 nmol) or corticotropin-releasing hormone (CRH, 0.5 or 5 nmol) through the cannula, and blood samples were taken 30 and 0 min prior to and 15, 30, 60 and 90 min after the injection. Cortisol concentrations in plasma were determined by enzyme immunoassay. Administration of 0.5 nmol NPB resulted in a significant increase in the cortisol concentration compared with the vehicle control, whereas the cortisol concentration after lower or higher doses of NPB did not differ from the control value. Thus, an icv injection of NPB produced a bell-shaped dose-response of cortisol concentration. Administration of PrRP had no significant effect on the cortisol concentrations at any dose examined. Icv injection of CRH dose-dependently increased plasma cortisol concentrations. These results demonstrate that central NPB stimulates cortisol secretion, suggesting that this neuropeptide plays some roles in control of the HPA axis in sheep. On the other hand, unlike its role in rodents, PrRP is unlikely to be involved in control of the HPA axis in this species.  相似文献   
924.
DNA fragments of Anaplasma bovis and Anaplasma phagocytophilum were detected in cattle on Yonaguni Island, Okinawa, Japan. Although the pathogenesis and epidemiology of these pathogens have not yet been clarified, this is the first detection of their presence in cattle from Japan.  相似文献   
925.
Ocean Expo Park, established in 1976 on subtropical Okinawa Island, Japan, has approximately 8000 planted or naturally grown trees in an area of 77.2 ha. Windfall of these trees occurs mainly due to typhoons; wood chips made from the trunks and roots of windfall trees are commonly used as mulching material throughout the park areas, despite possible infection by pathogenic fungi such as Phellinus noxius, the pathogen causing brown root rot. P. noxius is distributed in tropical and subtropical areas worldwide and has a broad host range. The fungus can infect host plants with mycelia via root-to-root contact or with basidiospores. Here, we report the current status of tree damage caused by brown root rot in the park and infer the infection routes of P. noxius based on microsatellite markers. Among a total of 294 trees surveyed in the park, P. noxius was isolated from 13 trees of five species. P. noxius was observed more frequently on Ficus microcarpa than on other tree species. Ficus superba var. japonica was identified as a new host species, and Bombax ceiba was first recorded as a host plant of P. noxius in Japan. Among the 13 P. noxius isolates from the diseased trees, 2 isolates from adjacent diseased trees were considered to be of the same genet, while the other 11 isolates were different genets, indicating that infection by basidiospores occurred frequently among trees in the entire park, although spread via root systems also occurred between at least two adjacent trees. An identical genet was not detected at distant locations, which suggests that the disease does not spread via chips. However, mulching with chips can lead to wood decay due to decaying fungi other than P. noxius. Therefore, in accordance with the precautionary principle, the park currently prohibits the chipping and mulching of windfall or damaged trees and is considering disposal methods such as burning.  相似文献   
926.
The aim of the present study was to establish a simple method to monitor ovarian activity and non-invasively diagnose pregnancy in okapi (Okapia johnstoni). The feces of a female okapi were collected daily or every 3 days for 28 months. Steroids in lyophilized feces were extracted with 80% methanol, and the fecal levels of immunoreactive progestagens (progesterone and pregnanediol-glucuronide), androgen (testosterone), and estrogens (estradiol-17beta and estrone) were determined by enzyme immunoassays with commercially available antisera. Using the progesterone profiles, the durations of the luteal phase, follicular phase, and estrous cycle were determined to be 11.1 +/- 0.4, 5.3 +/- 0.6, and 16.5 +/- 0.7 days (n=22), respectively. Fecal levels of immunoreactive progesterone, pregnanediol glucuronide, and testosterone gradually increased from early pregnancy and peaked several months before parturition. More pregnanediol glucuronide was excreted in feces than progesterone during late pregnancy, but not during the estrous cycle. Although the fecal concentrations of immunoreactive estradiol-17beta and estrone change a little throughout pregnancy and non-pregnancy, they rose sharply and temporarily on the day following parturition. The present study indicates that fecal assays with commercial antisera for progesterone and pregnanediol glucuronide are useful for evaluating luteal activity and diagnosing pregnancy and indicates that estrogens might have some role as a trigger of parturition.  相似文献   
927.
Fracture is one of the most life-threatening injuries in horses. Fracture repair is often associated with unsatisfactory outcomes and is associated with a high incidence of complications. This study aimed to evaluate the osteogenic effects of gelatin/β-tricalcium phosphate (GT) sponges loaded with different concentrations/ratios of mesenchymal stem cells (MSCs) and bone morphogenetic protein-2 (BMP-2) in an equine bone defect model. Seven thoroughbred horses were used in this study. Eight bone defects were created in the third metatarsal bones of each horse. Then, eight treatments, namely control, GT, GT/M-5, GT/M-6, GT/M-5/B-1, GT/M-5/B-3, GT/M-6/B-1, and GT/M-6/B-3 were applied to the eight different sites in a randomized manner (M-5: 2?×?105 MSCs; M-6: 2?×?106 MSCs; B-1: 1 μg of BMP-2; B-3: 3 μg of BMP-2). Repair of bone defects was assessed by radiography, quantitative computed tomography (QCT), and histopathological evaluation. Radiographic scores and CT values were significantly lower in the control group than in the other groups, while they were significantly higher in the GT/M-5/B-3 and GT/M-6/B-3 groups than in the other groups. The amount of mature compact bone filling the defects was greater in the GT/M-5/B-3 and GT/M-6/B-3 groups than in the other groups. The present study demonstrated that the GT sponge loaded with MSCs and BMP-2 promoted bone regeneration in an equine bone defect model. The GT/MSC/BMP-2 described here may be useful for treating horses with bone injuries.  相似文献   
928.
There are no reported spontaneous cases of pancreatic ductal adenocarcinoma (PDAC), and there are few reports about chemically-induced PDAC in rats. We encountered a PDAC in a Wistar Hannover GALAS rat that had been subjected to a medium-term multiorgan carcinogenicity bioassay. This article describes the histological and histochemical findings of the tumor. The tumor was located in the pancreatic tissue and had not invaded the liver parenchyma or the mucosal layer of the alimentary tract. The tumor cells were atypical and were mainly arranged in small tubules. In addition, abundant stroma and mucus production were observed in the tumor. In an immunohistochemical examination, the tumor cells were positive for cytokeratin, Sox9 and pancreas duodenum homeobox 1 and negative for amylase 2A and insulin. Therefore, the tumor was diagnosed as a PDAC based on its histological and histochemical findings. We considered that the tumor was caused by the carcinogens administered during the abovementioned bioassay.  相似文献   
929.
930.
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