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1.
Abstract This study was undertaken to elucidate the pathogenesis of the hydrocephalus and aqueductal stenosis induced by intracerebral mumps virus inoculation in suckling hamsters.
Mild ventricular dilatation became apparent after 5 days of inoculation. Focal denuding of the ependymal layer and subsequent aqueductal stenosis were observed by 14 days after inoculation. The virus antigen was detected not only in the ependymal cells and choroid plexus, but also in some neurons in the cerebral cortex, hippocampus, midbrain and cerebellum. In the cerebral aqueduct, the orderly arrangement of the cilialy clusters was destroyed on the 5th day after inoculation. After 10 days, proliferation of GFAP positive cells was noticed around the cerebral aqueduct and subsequently caused aqueductal stenosis. In the advanced state of hydrocephalus, the cerebellum was displaced downward and showed an elongated, atrophic and sleevelike structure similar to the Arnold-Chiari malformation. It was suggested that the extensive damage of the ependymal cilia may account for early ventricular dilatation, and subsequent aqueductal stenosis with glial proliferation is the main cause of the advanced hydrocephalus. It has not yet been determined whether the mumps virus can pass through the human placenta or not. If it can, however, our results strongly suggest that mumps virus infection in the human fetus will cause congenital hydrocephalus.  相似文献   
2.
HtrA2 is up-regulated in the rat testis after experimental cryptorchidism   总被引:3,自引:0,他引:3  
AIM: The aim of the present study was to elucidate the role of high temperature requirement A2 (HtrA2) in germ cell loss in the heat-stressed testis. METHODS: We examined the expression of HtrA2, caspase-9 activity and proteolytic activity of HtrA2 in the rat testis, and their in vivo responses to experimental cryptorchid treatment. RESULTS: Northern analysis revealed the expression of HtrA2 mRNA peaked at days 1 and 7 after cryptorchid treatment. While expression of HtrA2 mRNA was seen in the spermatogonium, spermatocytes and some spermatids in normal adult rat testis, experimental cryptorchidism treatment resulted in a marked increase in its signal intensity in spermatocytes and some spermatids, and the layers of spermatogonium and early primary spermatocytes became negative at days 1 and 7 after the treatment. However, the spermatogonium, Sertoli cells and interstitial cells appeared to have strong intensities at days 14, 28 and 56 after the treatment. Western analysis revealed the expression of HtrA2 protein peaked at day 2 coinciding with the increase of positive spermatogonium, the appearance of protein-positive interstitial cells, and day 28 coinciding with the reappearance of protein-positive interstitial cells. Caspase-9 activity peaked at day 2 and HtrA2 proteolytic activity peaked at day 28. Consequently, the first peak of HtrA2 mRNA expression was followed by the peak of caspase-9 activity and the second peak was followed by the peak of proteolytic activity; however, the second peak of mRNA expression had considerable chronological difference from that of the protein. CONCLUSION: These findings suggest the probabilities that the heat stress results in germ cell death by a caspase-independent manner with the elevation of HtrA2 proteolytic activity, as well as a caspase-dependent manner with the elevation of caspase-9 activity.  相似文献   
3.
Large dendritic cells were cultured from facial angiofibromas of six patients with tuberous sclerosis. The cells were examined immunocytochemically for expression of selected cytoskeletal and non-structural proteins and the results compared with the staining profiles obtained with normal skin fibroblasts and normal glial cells. In similarity to normal glia, the angiofibroma stroma cells expressed glial fibrillary acidic protein (GFAP). Conversely, by analogy to fibroblasts, the abnormal stroma cells produced fibronectin and did not react with the antibody to S-100 protein. By immunogold labelling it was established that GFAP and vimentin were co-localized in intermediate filaments of the angiofibroma cells.  相似文献   
4.
PROBLEM : To determine if patients with unexplained recurrent miscarriage have a deficiency of decidual immunosuppressor cells that produce transforming growth factor β type 2, as has been found in mice with abortion due to rejection and/or trophoblast failure. METHODS : Decidual biopsy specimens were taken as near to the placental attachment site as possible under ultrasound guidance from first trimester legal termination (control) patients with recurrent miscarriage and non-viable pregnancy, and from patients with sporadic missed abortion. The tissue was tested for TGFβ-2+ suppressor cells by in situ hybridization, immunohistochemistry, and analysis of supernatants. RESULTS : TGFβ-2-related suppressor molecules similar but not identical to those identified in pregnant mice were released by decidual lymphoid cells. Fifty percent of 14 recurrent miscarriage patients showed a lack of suppressor cells and 59% were subnormal in comparison to 20 controls and 5 sporadic miscarriage patients, where 80–85% of the patients had detectable suppressor cells. CONCLUSIONS : Suppressor cell deficiency is compatible with a role for rejection and/or trophoblast failure in some patients with recurrent miscarriage. Presence of suppressor cells in most patients with missed abortion (4/5) is compatible with an alternative cause of fetal death, similar to findings reported in genetic fetal death mice.  相似文献   
5.
6.
The role of serum eosinophil cationic protein levels in allergic rhinitis is controversial. It is also unclear whether with immunotherapy it is possible to reduce these serum levels in allergic diseases. We studied serum eosinophil cationic protein levels in patients with cedar-induced allergic rhinitis and compared them with non-atopic controls. The second aim of this study was to elucidate whether immunotherapy is capable of decreasing the seasonal elevation in serum eosinophil cationic protein levels in seasonal allergic rhinitis. The serum eosinophil cationic protein levels of the untreated patient group were significantly higher than those of the non-atopic controls. The levels in patients who received immunotherapy for 2 yr were also significantly higher than those of the non-atopic controls. However, the levels were not different between the patients undergoing immunotherapy for over 3 yr and the non-atopic controls. The serum levels of the 31 patients treated with immunotherapy correlated with the duration of immunotherapy. In conclusion, the serum eosinophil cationic protein levels are higher in untreated patients with seasonal allergic rhinitis and this seasonal activation in circulating eosinophils decreases gradually during immunotherapy, but this inhibitory effect becomes apparent only after a number of years of immunotherapy. This prevention of seasonal eosinophil activation is one of the mechanisms responsible for the clinical effect of immunotherapy.  相似文献   
7.
Cystic lymphangioma of the gall-bladder: A case report   总被引:4,自引:0,他引:4  
Intra-abdominal cystic lymphangiomas are rare lesions that can be difficult to diagnose. We present a report of a patient with a giant multilocular cystic lesion in the abdomen. Ultrasonography and computed tomography scans of the abdomen revealed that the cyst had originated in the gallbladder fossa. There was some calcification and thickening of the cyst wall. Endoscopic retrograde cholangiopancreatography demonstrated a medially deviated common bile duct, an elongated cystic duct and an inferior compressed gallbladder. There was no apparent communication between the cyst and the biliary tract; however, an abdominal angiogram revealed that the lesion was supplied by a branch of the cystic artery. Histological findings obtained intra-operatively were consistent with a cystic lymphangioma. Its characteristic histology was observed in the subserous layer of the gall-bladder. This case is a rare instance of a cystic lymphangioma originating in the gall-bladder.  相似文献   
8.
Ruptured intracranial aneurysms are rare in the pediatric population compared to adults. This has incited considerable discussion on how to treat children with this condition. Here, we report a child with a ruptured saccular basilar artery aneurysm that was successfully treated with coil embolization. A 12-year-old boy with acute lymphoblastic leukemia and accompanying abdominal candidiasis after chemotherapy suddenly complained of a severe headache and suffered consciousness disturbance moments later. Computed tomography scans and cerebral angiography demonstrated acute hydrocephalus and subarachnoid hemorrhage caused by saccular basilar artery aneurysm rupture. External ventricular drainage was performed immediately. Because the patient was in severe condition and did not show remarkable signs of central nervous system infection in cerebrospinal fluid studies, we applied endovascular treatment for the ruptured saccular basilar artery aneurysm, which was successfully occluded with coils. The patient recovered without new neurological deficits after ventriculoperitoneal shunting. Recent reports indicate that both endovascular and microsurgical techniques can be used to effectively treat ruptured cerebral aneurysms in pediatric patients. A minimally invasive endovascular treatment was effective in the present case, but long-term follow-up will be necessary to confirm the efficiency of endovascular treatment for children with ruptured saccular basilar artery aneurysms.  相似文献   
9.
为了筛选出适宜于平原荒漠区种植的高产燕麦新品种,在呼图壁旱生牧草种子基地采用随机区组试验设计,对10份饲用燕麦品种的生产性能进行分析和比较。结果表明,各燕麦品种6月下旬进入抽穗期;收获时,太阳神、美达和牧乐思的株高均在106 cm以上,它们的鲜草产量也均达到3 000 kg/666.67 m^2以上,显著高于其他品种,但由于受干鲜比影响,大汉的干草产量最高为781.90 kg/666.67 m^2,其次是太阳神。经综合评价,太阳神的株高、鲜干草产量均较高,且其干鲜比低,适口性好,生育期居中,表现优良,适宜在北疆平原荒漠区推广种植。  相似文献   
10.
天山花楸醋酸乙酯部位化学成分研究   总被引:3,自引:1,他引:2  
目的:研究天山花楸的化学成分,为进一步拓展天山花楸的药理功效,开发利用天山花楸奠定基础.方法:利用硅胶、树脂柱色谱等手段进行分离,结合现代波谱技术(~1H-NMR,~(13)C-NMR,IR等)及现代分析方法鉴定化合物的结构.结果:从天山花楸乙醇提取浸膏中分离得到6个化合物,鉴定为苯甲酸(bcnzoic acid, 1),苄基-O-β-D-吡喃葡萄糖苷(bcnzvl-O-β-D-glucopyranoside,2),乌苏酸(ursolic acid,3),2α-羟基乌苏酸(26α-hydfoxyursolic acid,4),金丝桃苷(hyperoside,5),槲皮素-3-D-葡萄糖苷(quercetin-3-D-glucoside,6).结论:化合物1~5为首次从天山花楸中得到.  相似文献   
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