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81.
An orbivirus was isolated from a sample from the ornithophilic mosquito Culex sasai in Japan. The virus, designated Koyama Hill virus (KHV), replicated to high titer in a mosquito cell line and to a low titer in an avian cell line, but the release of progeny viruses was not observed in mammalian cell lines inoculated with KHV. Electron microscopic examination of KHV-infected mosquito cells showed approximately 70-nm virus particles and viral tubules typical of members of the genus Orbivirus, family Reoviridae. KHV efficiently replicated in Cx. sasai mosquitoes, suggesting a potential vector species for KHV transmission in nature. Full-length viral genome sequencing and phylogenetic analysis revealed that KHV is closely related to Umatilla virus (UMAV) and Stretch Lagoon orbivirus (SLOV). This suggests that KHV is a new member of the species Umatilla virus, an orbivirus species not previously observed in East Asia. The KHV genome segment encoding NS1 contains a notable sequence deletion and heterogeneity compared with a prototype UMAV, which may affect its growth properties and pathogenicity in host cells. These results provide new insights into the genetic diversity and geographic distribution of members of the species Umatilla virus.  相似文献   
82.
In periodontal therapy, the use of low-level diode lasers has recently been considered to improve wound healing of the gingival tissue. However, its effects on human gingival epithelial cells (HGECs) remain unknown. The aim of the present study was to examine whether high-frequency low-level diode laser irradiation stimulates key cell responses in wound healing, proliferation and migration, in primary cultured HGECs in vitro. HGECs were derived from seven independent gingival tissue specimens. Cultured HGECs were exposed to a single session of high-frequency (30 kHz) low-level diode laser irradiation with various irradiation time periods (fluence 5.7–56.7 J/cm2). After 20–24 h, cell proliferation was evaluated by WST-8 assay and [3H]thymidine incorporation assay, and cell migration was monitored by in vitro wound healing assay. Further, phosphorylation of the mitogen-activated protein kinase (MAPK) pathways after irradiation was investigated by Western blotting. The high-frequency low-level irradiation significantly increased cell proliferation and [3H]thymidine incorporation at various irradiation time periods. Migration of the irradiated cells was significantly accelerated compared with the nonirradiated control. Further, the low-level diode laser irradiation induced phosphorylation of MAPK/extracellular signal-regulated protein kinase (ERK) at 5, 15, 60, and 120 min after irradiation. Stress-activated protein kinases/c-Jun N-terminal kinase and p38 MAPK remained un-phosphorylated. The results show that high-frequency low-level diode laser irradiation promotes HGEC proliferation and migration in association with the activation of MAPK/ERK, suggesting that laser irradiation may accelerate gingival wound healing.  相似文献   
83.
Protection of hepatocytes from ischemia-reperfusion injury is a clinically important issue. The purpose of this study was to evaluate changes in acute liver damage and recovery after ischemia-reperfusion in rats with asialoglycoprotein receptor (ASGP-R) ligand. Ischemia was induced by clamping the hepatoduodenal ligament for 90 min. At 1, 3, 24, 48 hr, 1 and 2 wk after reperfusion, I-125-GSA was injected. Five min after injection, blood samples were obtained and the liver was removed. Several regions from each lobe were dissected, weighed and counted. Mean uptakes (% dose/g) in the liver and blood samples were calculated. Histologic sections stained with hematoxylin-eosin (H-E) stain showed ischemic damage at 1 and 3 hr, and focal hepatocyte necrosis at 24 hr. Predominant massive necrosis was not seen. The mitotic index with H-E stain and proliferating cell nuclear antigen (PCNA) labeling index were highest at 1 wk, indicating liver regeneration. At 1 and 3 hr, liver uptake was significantly decreased, and blood uptake was significantly increased, indicating decreased tissue blood flow and ischemic damage. Liver uptake showed significant increases at 48 hr and 1 wk, and was the highest at 1 wk, indicating liver regeneration during the convalescence stage. ASGP-R binding may provide valuable information on ischemia-reperfusion injury and recovery.  相似文献   
84.
The proliferation of lymphocytes induced by Propionibacterium acnes (P. acnes) was measured by the in vitro incorporation of 3H-thymidine. The mean response rate of alveolar lymphocytes obtained by bronchoalveolar lavage was 2.23 +/- 0.89 in nine untreated sarcoidosis patients, 0.85 +/- 0.17 in five sarcoidosis patients given corticosteroids and 0.78 +/- 0.29 in 11 controls. The proliferation was significantly enhanced in the untreated patients compared to both the treated patients (p less than 0.01) and controls (p less than 0.001), but there was no significant difference in response rates between the treated patients and controls. The response rate of alveolar lymphocytes was significantly higher in four active patients (3.05 +/- 0.61) than in four inactive patients (1.77 +/- 0.44) (p less than 0.05) and in the controls (p less than 0.001). In sarcoidosis patients, the response rates showed a good correlation with activities of serum lysozyme (r = 0.695, p less than 0.01), and with percentages of lymphocytes in bronchoalveolar lavage fluid (r = 0.591, p less than 0.05). There was a low correlation between angiotensin-converting enzyme activities and the response rates (r = 0.508, p less than 0.1). Neither peripheral blood lymphocytes in sarcoidosis patients nor in controls showed any response to P. acnes, but alveolar lymphocytes of the untreated active sarcoidosis patients were sensitive to P. acnes. The lymphocytes activated by P. acnes may play a central role in the induction of alveolitis in sarcoidosis patients.  相似文献   
85.
The aim here was to observe the immunohistochemical localization of osteoclast differentiation factor (ODF)/receptor activator of NF kappa B ligand (RANKL) in the rat periodontium. Rat mandibles were demineralized and embedded in paraffin, and horizontal and frontal sections were prepared for immunohistochemical analysis. In horizontal sections, immunolocalization of RANKL was marked in the distal area of the periodontium of molars in which osteoclasts appeared, due to physiological tooth drift. In frontal sections, RANKL immunoreactivity was localized on spindle-shaped mesenchymal cells around blood vessels near the bone surface in the periodontium. In addition, immunoreaction for RANKL was detected on structures that appeared to be elongated cell processes near blood vessels in frontal sections. Immunohistochemical examination for the general antigen of nerve-specific protein suggested a similarity between these structures and nerve fibres.  相似文献   
86.
To perform AIH, an artificial spermatocele was inserted into the epididymis for obstructive azoospermia (probably caused by congenital defect of the spermiduct on one side and by accidental vasosection in hernioplasty on the other). The graft used was a cup-shaped alloplastic spermatocele made of silicon-dacron, developed by Wagenknecht et al. The epididymal duct was incised microscopically. The graft was sutured to the epididymal involucrum, punctured through the scrotal skin by an injection needle and aspirated spermatozoa accumulated in the internal cavity, and subjected to AIH. Postoperatively, acceleration of spermatogenesis was attempted by injecting i.m. HCG 2,000 U-HMG 150 U twice a week, but spermatozoa both qualitatively and quantatively sufficient to perform AIH could not be obtained. Spermatozoa were no longer found after two and a half postoperative months. Despite the present failure, we would like to develop a method of grafting of this kind as more precise therapeutic means through further technical improvements in grafting.  相似文献   
87.
A case of aortic stenosis complicated with complete atrioventricular block preoperatively was reported. The patient was a 73-year-old woman who had been suffering from dyspnea and fatigability. Preoperative echocardiography revealed severe left ventricular hypertrophy, marked left ventricular-aortic pressure gradient (144 mmHg), and the impairment of left ventricular distensibility. Therefore, DDD pacemaker was implanted in addition to aortic valve replacement. Postoperative cardiac catheterization revealed that cardiac output was increased about 25% by DDD pacing compared with VVI pacing. It is more reasonable to employ DDD pacemaker to the case of which distensibility is impaired.  相似文献   
88.
Effects of ovariectomy on trabecular structures of rat alveolar bone   总被引:12,自引:0,他引:12  
An association between postmenopausal osteoporosis and tooth loss has been proposed. However, histomorphometrical changes in alveolar bone following estrogen deficiency are rarely reported with data on microtrabecular structural changes. To clarify the relationship between estrogen deficiency and tooth loss, we histomorphometrically analyzed the trabecular structural changes of mandibular alveolar bone in ovariectomized rats. Twenty-four adult female Fischer rats were used. Eight rats were sacrificed on day 0 (baseline). The remaining 16 rats were divided into two groups. One group was ovariectomized bilaterally (OVX) and the other group was subjected to sham surgery (Sham). After administration of tetracycline and calcein, the animals were sacrificed 60 days after surgery. Bone histomorphometry, node-strut analysis and measurement of thickness of alveolar bone proper were performed on the interradicular septum of the first molar on the sagittal surface. The trabecular bone volume and trabecular number of the OVX group were significantly lower than those of the baseline and Sham groups. All of the bone resorptive and formative parameters of the OVX group were significantly higher (about one-and-a-half times) than those of the Sham group. Several osteoclasts were seen lining the irregular, eroded surface facing the bone marrow in the OVX group. Furthermore, the OVX group tended to have low microtrabecular stiffness and showed significantly thinner distal alveolar bone proper than in the baseline and Sham groups. In summary, estrogen deficiency caused osteoporotic changes and thin alveolar bone proper in the interradicular septum of rat first molar. This phenomenon might accelerate destruction of alveolar bone and tooth loss, especially in elderly women affected by periodontal disease.  相似文献   
89.
This study was designed to investigate quantitative changes in osteoclast generation in rat periodontium following ovariectomy. Wistar rats, aged 9 weeks, were subjected to either ovariectomy (OVX) or sham surgery. Osmotic pumps were implanted in 24 rats and either 17beta-oestradiol or vehicle solution were infused continuously. The rats were assigned to one of the following groups: (1) OVX+vehicle; (2) sham+vehicle; or (3) OVX+ 17beta-oestradiol. On the days 7 and 14 after surgery, four rats in each group were killed. Mandibles were demineralized and embedded in paraffin. Frontal sections of alveolar bone in the region of the first molar were cut for enzyme histochemistry and immunohistochemistry. On day 7, there was no significant difference in the number of tartrate-resistant acid phosphatase (TRAP)-positive cells located on bone surfaces in either group. However, the number of TRAP-positive mononuclear cells that were separated from the bone surface was significantly higher in group 1 than in groups 2 and 3. On the day 14, the number of TRAP-positive cells in group 1, which were attached to the bone surface, was significantly higher than had been apparent on day 7. There were also significant increases in the number of nuclei of TRAP-positive cells attached to the bone in group 1 compared with groups 2 and 3 on day 14. These findings demonstrate that oestrogen deficiency induces of osteoclastogenesis in the rat periodontium and that quantitative changes in osteoclastogenesis could be prevented by E2 infusion.  相似文献   
90.
Several species of captive and wild birds have been found to be infected with various avian blood protozoa in Japan. We investigated the prevalence and transmission of avian malaria parasite and determined the bloodmeal hosts of mosquitoes collected in a zoological garden in Tokyo, Japan, by using the polymerase chain reaction. In total, 310 unfed and 140 blood-fed mosquitoes of seven species were collected by using sweep nets and CDC traps. Bloodmeal identification indicated that mosquitoes had fed on 17 avian and five mammalian species, including captive animals. The results of avian malaria parasite detection from mosquitoes with avian bloodmeals indicated that Culex pipiens pallens Coquillet is a main vector of avian Plasmodium in the current study site and that some captive and wild birds could be infected with avian malaria parasites. Furthermore, the distances between the collection site of blood-fed mosquitoes and the locations of their blood-source captive animals were estimated. Most females with fresh bloodmeals were found within 40 m of caged animals, whereas half-gravid and gravid females were found between 10 and 350 m from caged host animals. We demonstrated that blood-fed mosquitoes can provide useful information regarding the mosquito vector species of avian malaria parasites and allows for noninvasive detection of the presence of avian malaria parasites in bird populations.  相似文献   
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