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791.
Bloom syndrome (BS) involves the clinical features of telangiectatic erythema, immunodeficiency, and an increased risk for cancer. In order to clarify the pathogenetic significance of the responsible gene, BLM, which encodes a protein possessing homology to Escherichia coli RecQ helicase, the immunohistochemistry of BLM was examined in human brains and visceral organs from fetuses to adults and an adult with BS, using anti‐BLM antibodies. Purkinje cells exhibited positive BLM immunoreactivity from 21 gestational weeks (GW), which transiently increased at approximately 40 GW. Neurons of the pontine tegmentum were immunolabeled from the early fetal period. In visceral organs, positive BLM immunoreactivity was observed in the Hassal corpuscles in the thymus from 24 GW, in beta‐cells in the Langerhans islets of the pancreas from 36 GW, and in sperm cells and sperms of the testes from 11 years of age. But in a patient with BS, it was negative in the pancreas and testis tissues examined. The characteristic effect of BLM on specific cells in different periods suggests that the BLM gene product is closely related to neuronal development as well as immune, insulin secretory and sperm functions, which appear in different periods, and disorders of which are major symptoms of BS.  相似文献   
792.
We present the developmental changes of peroxisomal enzymes, catalase, -bifunctional protein ( -BF) and -bifunctional protein ( -BF), in the normal brains, and patients with -BF deficiency, a new peroxisomal disease. -BF immunoreactivity was observed in controls as early as 13 gestational weeks (GW) and increased with maturation. The adult pattern with fine granule staining of somata and dendrites became apparent in adolescence. -BF appeared at 20 GW in the cerebral cortex and Purkinje cells and positive glia appeared early in the white matter at 17 GW, and then increased with age. Catalase-positive neurons were identified in the same manner as -BF, -BF deficiency in both fetus and infant showed markedly diminished enzyme immunoreactivity. Patients demonstrate reduced -BF expression. Zellweger syndrome shows decreased expression for the three proteins. This study shows that the peroxisomal enzymes may be closely related to neuronal maturation and gliogenesis in human brain and to disturbance of neuronal migration as seen in Zellweger syndrome significant. -BF deficiency may exhibit a range of symptoms during the neonatal and early infantile periods some of which may be similar to Zellweger syndrome.  相似文献   
793.
Periventricular leukomalacia: relation to gestational age and axonal injury   总被引:5,自引:0,他引:5  
Eighty-five infants ranging from 22 to 41 weeks gestation were diagnosed as having periventricular leukomalacia (PVL) using traditional neuropathologic methods. The lesions were also studied by immunocytochemistry for β-amyloid precursor protein (β-APP), a glycoprotein that has been observed in PVL. Using this technique, the distribution of white matter tissue necrosis was defined as focal, widespread, and diffuse. The type of PVL correlated with the gestational age at birth. The youngest infants tended to demonstrate widespread necrosis, and the oldest infants exhibited more focal necrosis. β-APP immunopositivity was present in the axons around the foci of white matter necrosis in 76% of the patients and in the neurons of the adjacent cortex in 66% of the patients. In age-matched control patients, there was no β-APP reactivity in the cerebral white matter or the cortex. In most patients the distribution of β-APP–positive axons proved to be a useful marker for demonstrating the type of PVL; however, the relationship of β-APP to the pathogenesis of PVL requires further study.  相似文献   
794.
A total of 25 patients with severe peritoneal dissemination underwent chemohyperthermic peritoneal perfusion (CHPP). The primary tumors in these patients comprised colorectal cancer (n = 14), ovarian cancer (n = 6), cervical cancer, (n = 1), small bowel cancer (n = 1), pseudomyxoma retroperitonei (n = 1), cystoadenocarcinoma of liver (n = 1), and pancreas cancer (n = 1). The intraperitoneal perfusion was carried out with a magnet pump for 60 min. The heated perfusate contained anticancer drugs to act synergistically with the hyperthermia. The intraperitoneal temperature was maintained at 42.0-42.5 degrees C. Eight of 25 patients showed CR, four PR, ten NC, and three PD, and the percentage (CR+PR) representing the overall efficacy rate was 48.0%. The morbidity rate was 8% (2/25) and there was no treatment-associated mortality. The percentage (CR+PR) of the patients with colorectal cancer was 57%; ovarian cancer, 50%; and other malignancies, 20%. The 1 year-and 3 year-survival rates of all the patients were 55% and 26%, respectively. The median survival periods of the CR, PR, NC, and PD groups were 4.0, 1.0, 1.0, and 0.7 years, respectively. The survival curve of the CR group was the best of all the groups (P = 0.02). These results indicated that CHPP was a feasible therapy and exerted a direct anticancer effect on peritoneal dissemination especially in the case of ovarian cancer, and the prognosis of complete responders was improved.  相似文献   
795.
796.
The mechanism of weight loss induced by the growth of malignant tumors is still unknown. We investigated it by focusing on apoptosis of skeletal muscle. VX2-tumor was implanted into rabbits and the apoptotic index (AI) of skeletal muscle was measured by in situ end-labeling assay. Plasma of the tumor-bearing rabbits was perfused repeatedly through non-coated charcoal resin. The AI reached 54.6% early after tumor implantation, when weight loss amounted to an 18% decrease in lean body mass (LBM) without change in muscle DNA synthesis or urinary 3-methylhistidine/ creatinine ratio (3-MH/Cr). When the decrease of LBM reached 30%, DNA synthesis was decreased by 48% and 3-MH/Cr was increased by 104%, whereas AI was only 4.7%. The plasma perfusion did not prevent apoptosis in muscle, but unproved LBM, DNA synthesis, and 3-MH/Cr. There may be two mechanisms of muscle depletion during the tumor growth: apoptosis in the early stage and metabolic abnormalities in muscle in the late stage.  相似文献   
797.
The mechanisms of the lymph node metastasis remain unclear. We demonstrate the role of MT1-MMP on the lymph node metastasis using in vivo experimental model of lymph node metastasis by orthotopic implantation of MT1-MMP transfected gastric cancer cell line in the stomach of nude rats. TMK-1 cell line without expression of MT1-MMP was transfected with the pcDNA3 plasmid containing a 3.4-kb MT1-MMP cDNA fragment by calcium phosphate method, and the transfected cell line was designated as TMK-MT. Western blot and RT-PCR analyses showed the specific bands corresponding to MT1-MMP in the TMK-MT cells. By gelatin zymography, the activated form (62-kDa) of MMP-2 was identified in the medium of TMK-MT cell line, but was not detected in TMK-1 cells. Six weeks after orthotopic implantation of TMK-1 and TMK-MT xenografts of nude mouse-subcutaneus tumor into the stomach of nude rats, gastric tumors were found in all the animals. Histologically, the lymphatic invasion was found in the submucosa of the TMK-MT gastric tumors. Lymph node metastasis was not detected in nude rats bearing TMK-1 gastric tumor (0/8). In contrast, lymph node metastasis was detected in five out of 8 rats, bearing TMK-MT gastric tumor. MT1-MMP immunoreactivity was found on the cell membrane and cytoplasm of TMK-MT cells not only in the lymph node metastasis but also in the stomach tumor. These results suggest that MT1-MMP overexpression induced by transfection of its gene may promote lymph node metastasis of transformed cells. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
798.
Laser surgery has been used to successfully treat patients with perennial allergic rhinitis. We examined whether the numbers and types of sensitized allergens influence the effects of surgery. Two different groups (those allergic to house dust mites only, and those allergic to house dust mites and Japanese cedar pollen) prospectively underwent the same course of laser turbinectomy during the pollen dispersion season. The symptom scores for nasal obstruction significantly decreased in both groups, but the improvement of sneezing and rhinorrhea was less pronounced in the pollen group. We used acoustic rhinometry to measure postoperative changes in the nasal dimensions. Four months after treatment, the minimum cross-sectional area and nasal cavity volume had increased, respectively, by 61.7% and 30.7% in the house dust group, and by 30.7% and 16.2% in the pollen group. We conclude that laser surgery can be successfully applied to patients whose allergies show seasonal exacerbation by airborne pollen.  相似文献   
799.
800.
Open in a separate window OBJECTIVESWe performed a comparative analysis of the performance of video-assisted thoracic surgery (VATS) lobectomy simulation using three-dimensional-printed Biotexture lung models by surgeons classified according to their level of expertise. The aim of this study was to investigate the association between surgeons’ experience and time to complete the VATS lobectomy simulation. METHODSParticipants were divided into 3 groups: group A included those who had no experience of actual VATS lobectomy (n = 11), group B included those who had performed 5–10 VATS lobectomies (n = 12) and group C included those who had performed >100 VATS lobectomies (n = 6). Their performances were assessed based on total procedure time, duration to the exposure of the vessels, ligation of the arteries and stapling of the fissures. After the simulation, a questionnaire survey was performed.RESULTSThe median total procedure time was significantly shorter in the group of surgeons with more experience (A vs B, P <0.001; B vs C, P =0.034; A vs C, P <0.001). Regarding ‘the exposure of all the vessels to be resected’ and ‘ligation of the arteries’, group B completed these steps in less time than group A (P =0.024 and P =0.012, respectively). In the questionnaire, all groups answered that this simulation was useful for novices to improve their skills.CONCLUSIONSAlthough time to complete the VATS lobectomy simulation is only a part of evaluation points for real skills, this model can facilitate basic skill acquisitions for novices.  相似文献   
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