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61.
We previously reported that extremely low frequency electric fields (ELF-EFs) affect energy metabolism in stressed conditions. To further confirm this, the effect of exposure to ELF-EFs on the experimental ischemic rat was examined. The test was based on a comparison of rats treated with EF alone, ischemic surgery alone, the combination of EF with ischemic surgery, or no treatment (double sham). The EF condition used in this study was an alternating current of 50 Hz EF at 17 500 V/m intensity for 15 min per day. The exposure to EF in ischemic rats significantly decreased plasma levels of free fatty acids and triglycerides, compared to those of the no treatment or EF alone group. The plasma lactate levels of two ischemic groups peaked on experimental day-4 and gradually decreased until the end of the study. The changes in the lactate levels induced by ischemia did not show any difference between rats treated with ischemia alone or a combination of ischemia with an EF. Any changes in plasma levels of glucose and creatine phosphokinase activity were not influenced by EF treatment. These results indicate that the EF effect on glycolysis parameters, plasma lactate or glucose levels, does not appear in a highly stressed condition and that EF effects varied dependent on the condition of organism but ELF-EF used in this study have impact on lipid metabolism parameter in a hind-limb ischemic rat. However, further studies are needed to elucidate the association of ELF-EF with the lipid metabolism system.  相似文献   
62.
Although the release of growth hormone (GH) is known to be regulated mainly by GH-releasing hormone (GHRH) and somatostatin (SRIF) secreted from the hypothalamus, ghrelin also may be involved in GH release during juvenile period. We have examined plasma concentrations of acylated ghrelin, desacyl ghrelin, and GH in juvenile beagle dogs. Plasma acylated and desacyl ghrelin levels changed through aging; however, there was no closely correlation between ghrelin, body weight and circulating GH levels during juvenile period. The increase in body weight was essentially linear until 8 months of age, whereas plasma GH concentrations exhibited bimodal peaks for the meanwhile. The results suggest that ghrelin may not play internal cueing in GH secretion in juvenile beagle dogs.  相似文献   
63.
An intact male beagle dog aged 1 year was referred because of shortness of breath, exercise intolerance and cardiac murmur. Based on the results from electrocardiography, thoracic radiography and echocardiography, the dog was diagnosed as Ebstein's anomaly. Although the orally administered digoxin, vasodilators and diuretics partially improved congestive signs, the dog became to be refractory and died 20 months after the diagnosis. Necropsy confirmed malformation and apical displacement of the basal attachment of tricuspid valve leaflets.  相似文献   
64.
Nuclear magnetic resonance (NMR) microscopy is a magnetic resonance imaging method with enhanced spatial resolution due to the use of a high static magnetic field and high magnetic field gradients. It is considered to be a useful tool for non-invasive and continuous investigation of tissue and organs at the histological level. In this study, we applied NMR microscopy to assessment of morphology in mouse embryos using a developmental disorder model induced by retinoic acid administration. Pregnant mice were given 50 mg/kg all-trans retinoic acid at 8.5 dpc. Embryos were collected at several time points after treatment and examined by NMR microscopy after fixation. Two-dimensional and three-dimensional spin echo sequences were used. Tissue contrast on two-dimensional images changed according to length of repetition time and echo time, and also to developmental stage of embryos. Two-dimensional and three-dimensional images nondestructively demonstrated defects in development of the skeleton and soft tissue, e.g. hypoplasia of vertebrae in the lumbar and tail regions and dysplasia of the spinal cord, in embryos exposed to retinoic acid. These morphological abnormalities were confirmed by conventional assessment after imaging. Although further improvements are required, NMR microscopy will provide a new approach for multi-parameter assessment of embryonic development under physiological and pathological conditions.  相似文献   
65.
Previously, we histochemically examined the localization of tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) and its receptors in porcine ovarian follicles, and demonstrated a marked reduction in the expression of TRAIL-decoy receptor-1 (DcRI) in granulosa cells of atretic follicles. In the present study, to confirm the inhibitory activity of DcR1 in granulosa cells, granulosa cells prepared from healthy follicles were treated with phosphatidylinositol-specific phospholipase C (PI-PLC) to cleave glycophospholipid anchor of DcR1 and to remove DcR1 from the cell surface, and then incubated with TRAIL. PI-PLC treatment increased the number of apoptotic cells induced by TRAIL. The present finding indicated the possibility that TRAIL and its receptors were involved in induction of apoptosis in granulosa cells during atresia, and that DcR1 plays an inhibitory role in granulosa cell apoptosis.  相似文献   
66.
The accessory activity was reported in murine peritoneal cavity macrophage derived dendritic cells (PEC-DC) in a mixed lymphocyte reaction (MLR). Here we continue the characterization of the generated PEC-DC using the criteria of morphology, phenotype and other accessory function. We have demonstrated that murine peritoneal cavity macrophages can be induced to differentiate in vitro into cells exhibiting typical dendritic cell (DC) morphology, phenotype and function. The proliferative capacity of the progenitors was amplified in the first step of the culture (day 0-7) using a combination of early cytokines: interleukin 4 and granulocyte-macrophage colony-stimulating factor. The second step of the culture started at day 7 with the removal of early growth factors to allow differentiation and final maturation of DC during 2 days of culture with interferon gamma plus either Toxoplasma lysate antigen (TLA) or lipopolysaccharide (LPS), a bacterial agent as a DC maturing agent. The resulting DC population exhibited typical DC morphology and expressed higher levels of MHC class II and the co-stimulatory molecules CD80 and CD86 compared to the untreated peritoneal cells. The generated DC cells efficiently presented soluble protein antigen to CD3(+) spleen T cells.  相似文献   
67.
The prevalence of trypanosome infections in tsetse flies, Glossina pallidipes, collected from Chiawa and Chakwenga in Zambia with endemic trypanosomosis was assessed by polymerase chain reaction (PCR). Out of the 550 G. pallidipes, 58 (10.5%) flies were found to harbor trypanosome DNA. Infection rates of tsetse with Trypanosoma vivax universal, Trypanosoma congolense savannah, T. congolense forest and T. congolense kilifi were 4.2% (23/550), 4.7% (26/550), 1.1% (6/550) and 1.6% (9/550), respectively. To determine the mammalian hosts of T. congolense and T. vivax infections from the tsetse flies, mammalian mitochondrion DNA of blood meal in these flies were analyzed by PCR and subsequent gene sequence analysis of the amplicons. Sequence analysis showed the presence of cytochrome b gene (cyt b) of 7 different mammalian species such as human, elephant, buffalo, goat, warthog, greater kudu and cattle. Goats which were main livestock in these areas were further examined to know the extent of its contribution in spreading the infection. We examined the prevalence of trypanosome infections in the domestic goat population in 6 settlements in Chiawa alone. Of the 86 goats sampled, 4 (4.6%), 5 (5.8%), 4 (4.6%) and 4 (4.6%) were positive for T. vivax universal, T. congolense savannah, forest and kilifi, respectively. These findings showed that the host-source of trypanosome infections in vector fly give a vital information about spread of infection. The result of this study will certainly contribute in elucidating more the epidemiology of trypanosomosis.  相似文献   
68.
The purpose of this study was to evaluate the feasibility, safety, and efficacy of transcatheter closure in dogs with a congenital perimembranous ventricular septal defect (VSD) by using a detachable coil. No dogs showed any symptoms, and results of chest X-rays and ECGs were normal. The diameters of VSD ranged from 2 to 4 mm on echocardiogram. The defect was 2-2.5 mm from the aortic valve. A detachable coil (size 5 mm with 5 loops) designed for patent ductus arteriosus was delivered via the transarterial route. The device was successfully employed in all dogs. A minimal residual shunt was observed in all dogs even though Qp/Qs decreased. Hemolysis and a rate-dependent right-bundle branch block were observed in 1 dog, but there was no clinical significance. No major complication was noted. Pathologic examination after 1 year revealed that the coils were covered with tissue without significant damage to the His-Purkinje conduction system. In conclusion, transcatheter closure of a small perimembranous VSD with a detachable coil can be achieved without major complications or significant pathologic damage at the lesion site.  相似文献   
69.
In the present study, a novel antigenic protein expressed in the piroplasm stage of Theileria orientalis was characterized. A 4,707 bp genomic fragment amplified by PCR contained two open reading frames (ORFs). The deduced amino acid sequence of the first ORF showed significantly high similarlity to the ubiquitin carboxy terminal hydrolases/proteases while the second ORF (To ORF2) showed homology to several surface antigens of plasmodia. To ORF2 was expressed to determine whether the protein product is expressed by the parasite. In western blot analysis, bovine antiserum from a T. orientalis-infected calf recognized the recombinant protein containing a C-terminal part of the ORF expressed by baculovirus system. Western blot analysis with the anti-To ORF2 mouse serum recognized a 48 kDa protein in T. orientalis piroplasm lysates. Indirect immunofluorescence antibody test by confocal scanning laser microscopic analysis showed that antisera against the recombinant protein recognized T. orientalis piroplasm in the infected erythrocyte. The results from this study indicate that To ORF2 protein is expressed at the piroplasm stage and is immunogenic. This novel antigenic To ORF2 protein could be exploited for vaccine development against bovine piroplasmosis.  相似文献   
70.
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