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A study of double immunofluorescence-staining of immunoglobulins and sialic acids in the glomeruli from patients with IgA nephropathy is described. Renal biopsy specimens from patients with IgA nephropathy were stained with rhodamine-labeled antihuman IgA, IgG or IgM antisera and then stained with FITC-labeled Limulus polyphemus (LPA), Tricum vulgaris (WGA) or antihuman C3 antisera. Marked positive stainings of IgA and C3 and positive binding of LPA or WGA were observed in the glomerular mesangial areas from patients with IgA nephropathy. LPA or WGA were not bound with glomerular capillary walls from patients with moderate and advanced stages of IgA nephropathy, although depositions of IgA and C3 were markedly observed in such walls. There was a significant inverse correlation between the deposition of IgA and the binding of LPA or WGA in glomerular capillary walls obtained from these patients with IgA nephropathy. The levels of proteinuria from patients with moderate and advanced stages of IgA nephropathy were significantly higher than those with minimal and slight stages of such disease. It is suggested that the decrease of sialic acids in glomerular capillary walls might be due to a deposition of IgA in some patients with IgA nephropathy. It is concluded that high levels of proteinuria might be due to the decrease of sialic acids in glomerular capillary walls from patients with moderate and advanced stages of IgA nephropathy.  相似文献   
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PURPOSE: To clarify the appropriate concentration and dose of hypertonic saline solution (HSS) for preventing delayed neuronal death in the hippocampal CA1 subfield after transient forebrain ischemia in gerbils. METHODS: Thirty gerbils were randomly assigned to five groups: physiological saline solution (PSS) group, ischemia/reperfusion treated with PSS 2 mL x kg(-1); 5% HSS group, treated with 5% HSS 2 mL x kg(-1); 7.5% HSS group, treated with 7.5% HSS 2 mL x kg(-1); 10% HSS group, treated with 10% HSS 2 mL x kg(-1); 20% HSS group, treated with 20% HSS 2 mL x kg(-1). Transient forebrain ischemia was induced by occluding the bilateral common carotid arteries for four minutes. Five days later, histopathological changes in the hippocampal area were examined, and the degenerative ratio of the pyramidal cells were measured according to the following formula: (number of degenerative pyramidal cells/total number of pyramidal cells per 1 mm of hippocampal CA1 subfield) x 100. RESULTS: In PSS and 20% groups, neuronal cell damage was observed five days after ischemia. In the other three groups, these changes were not observed. The degenerative ratios of pyramidal cells were as follows; PSS group: 91.6 +/- 5.6%, 5% HSS group: 7.2 +/- 1.6%, 7.5% group: 8.3 +/- 1.4%, 10% HSS group: 6.2 +/- 1.1%, 20% HSS group: 85.8 +/- 8.7% (P < 0.05; PSS and 20% HSS vs three other groups). CONCLUSION: This study demonstrates that 5, 7.5 or 10% HSS 2 mL x kg(-1) may prevent delayed neuronal death in the hippocampal CA1 subfield after cerebral ischemia/reperfusion in gerbils.  相似文献   
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Regarding peroral cholangioscopy (POCS) for biliary disease, due to the recent appearance of a video cholangioscope that can obtain high‐quality images, it is possible to observe subtle changes of the biliary mucosa. In addition to the conventional observation method using POCS, the biliary mucosa with also observed with narrow band imaging (NBI) in one case of chronic cholangitis and four cases of extra hepatic bile duct tumor (three surgical cases). In the conventional observation method, the vessels in the surface layer of the biliary mucosa could be observed more clearly using NBI. In one case in which a tumor was observed, the irregularity of the biliary mucosa became clear on NBI, and the vessels inside a papillary tumor could also be easily observed. In another case of bile duct tumor, the conventional observation method showed a region in the proximity of the tumor where the vessels could not be seen clearly, but they could be seen clearly on NBI. In all of the cases, the bile juice was seen as red on NBI, which disturbed the observation. With POCS using NBI, it was possible to observe the vessels and irregularities in the surface layer of the biliary mucosa more clearly than with conventional observation methods.  相似文献   
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Abstract: Prevention of hyperacute rejection is a difficult and unsolved problem in xenotransplantation. Natural antibodies and complement activation have been known to play an important role in the xenotransplantation between discordant species pairs. In the present study, total blood exchange (TBE) was performed with pyridox-alated-hemoglobin-polyoxyethylene conjugate (PHP) solution (Ajinomoto Co., Inc., Kawasaki, Japan) before cardiac xenotransplantation in order to remove the immunoglobulins and prolong xenograft survival time. Guinea pigs and rats were used as the discordant species combination for donor and recipient. Two groups were established: Group 1, untreated control (n = 8) and Group 2, TBT with PHP solution (n = 8). The exchange blood transfusion was carried out at the rate of 15–20 ml/h utilizing PHP solution using a blood pump. After the blood exchange was processed, hematocrit (Ht) levels dropped to 4 or 5%, and a cardiac xenotransplantation was performed within 24 h. The levels of serum IgA, IgM, and IgG were decreased to less than 25, 25, and 10% of the base line, respectively, after blood exchange. A mean xenograft survival time in Group 2 was prolonged to 472 ± 74 min and to 10.4 ± 1.8 min in Group 1 (p < 0.01). A titer of the anti-guinea pig lymphocytotoxic antibody in rat serum was decreased to almost nil. The data from this study suggest that total blood exchange with PHP solution may be useful in preoperative removal of xenograft antibodies in xenotransplantation.  相似文献   
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Primary bladder tumor is the most frequent malignant tumor in the field of urology, whereas the incidence of secondary bladder tumor from a distant organ is quite rare. We report here a 21-year-old female patient with metastatic bladder tumor from gastric cancer. She came to our hospital with a complaint of only bladder irritability. Cystoscopical and cytological examinations revealed rhabdomyosarcoma of the bladder. She did not respond to radiation therapy and combined chemotherapy, consisting of actinomycin D, vincristine and cyclophosphamide, and died 91 days after admission. Autopsy revealed a primary tumor of poorly differentiated scirrhus carcinoma of the stomach. Thus this was a quite rare case of metastatic bladder carcinoma characterized by bladder irritability without gastrointestinal symptoms.  相似文献   
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Ruthenium red (3-5 microM) antagonism of the inhibitory effect of capsaicin (1 microM) on the contractile response to mesenteric nerve stimulation in the presence of hexamethonium (50 microM) and guanethidine (2 microM) was reversed significantly by sialic acid (2 mM) or neuraminidase (0.1 U/ml). These results suggested that ruthenium red at low concentrations inhibits the capsaicin-induced desensitization of activated Ca2+ influx into sensory nerves at least in part by binding to sialic acid residues.  相似文献   
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