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41.
To determine the role of free radical mechanisms in the pathogenesis of amyotrophic lateral sclerosis (ALS), cerebrospinal fluid concentrations of oxidized nitric oxide (NO) products (nitrite and nitrate) and reduced and oxidized forms of glutathione (GSH and GSSG, respectively) were compared between patients with the sporadic form of ALS (SALS) and controls. In the SALS patients, the nitrate levels were significantly higher (by 73%) in contrast to remarkably lower GSSG/GSH ratio, approximately 3-fold, compared to controls. These results suggest that NO production or oxidation is activated in SALS patients, leading to a decrease in superoxide radicals to oxidize GSH. The subsequent generation of a highly reactive anion, peroxynitrite, may play a causal role in the pathogenesis of SALS. 相似文献
42.
Intensified IgA mesangial deposits after administration of sheep anti-type IV collagen serum in mice
Sheep anti-type IV collagen serum was intravenously administered to male mice of the BALB/c, C3H and ddY strains, and their kidneys were morphologically studied monthly for 10 months thereafter. By immunofluorescence, the sheep IgG was seen to have immediately become conjugated to the glomeruli, mainly in a mesangial pattern. Successively, autologous mouse C3 and IgG appeared with the same type of distribution. Within 3 to 4 months after the start of the experiment, mouse IgA also appeared in the mesangium, especially in ddY mice. The intensity and frequency of mesangial IgA deposition and the serum IgA level increased with time in this strain. BALB/c and C3H mice also showed the same tendency of mesangial IgA deposition, although to a lesser degree. In summary, it was concluded that mesangial IgA deposition was due to non-immunological local trapping, on the basis of the results obtained by ELISA analysis of the sera and renal eluate. Although the ddY mouse is known to show spontaneous mesangial IgA deposition associated with a high serum IgA level with aging, these characteristics were much accelerated and intensified by this antiserum treatment. The relation of this observation to the pathogenesis of human IgA nephritis is discussed. 相似文献
43.
Masamichi Ishizaki Yukinari Masuda Yuh Fukuda Yuhichi Sugisaki Nobuaki Yamanaka Yozo Masugi 《Pathology international》1986,36(8):1191-1203
Focal glomerulonephritis was induced in rats, by a single intravenous injection of anti-Thy-1.1 antibody (ATS). One hour after the administration, the glomeruli of affected rats developed necrotic changes of the mesangial cells while after two hours, mesangiolytic changes appeared. From six days onwards, focal segmental mesangial proliferation which persisted until 30 days, occurred. This is thought to be the first report of experimental nephritis induced by pure anti-mesangial antibody. 相似文献
44.
HLA-DR Antigens in Pemphigus among Japanese 总被引:2,自引:0,他引:2
Masamichi Matsuyama Koji Hashimoto Yoshio Yamasaki Ryota Shirakura Reiko Higuchi Tetsuya Miyajima Hiroshi Amemiya 《Tissue antigens》1981,17(2):238-239
The frequency of HLA-DR4 was significantly increased at P < 0.02 in 37 unrelated pemphigus patients (62.2%), when compared with unrelated 73 healthy controls (30.1%). This antigen was more frequently found in pemphigus foliaceus (70.6%) than pemphigus vulgaris (55.8%). 相似文献
45.
Takasuka N Fujii H Takahashi Y Kasai M Morikawa S Itamura S Ishii K Sakaguchi M Ohnishi K Ohshima M Hashimoto S Odagiri T Tashiro M Yoshikura H Takemori T Tsunetsugu-Yokota Y 《International immunology》2004,16(10):1423-1430
The recent emergence of severe acute respiratory syndrome (SARS) was caused by a novel coronavirus, SARS-CoV. It spread rapidly to many countries and developing a SARS vaccine is now urgently required. In order to study the immunogenicity of UV-inactivated purified SARS-CoV virion as a vaccine candidate, we subcutaneously immunized mice with UV-inactivated SARS-CoV with or without an adjuvant. We chose aluminum hydroxide gel (alum) as an adjuvant, because of its long safety history for human use. We observed that the UV-inactivated SARS-CoV virion elicited a high level of humoral immunity, resulting in the generation of long-term antibody secreting and memory B cells. With the addition of alum to the vaccine formula, serum IgG production was augmented and reached a level similar to that found in hyper-immunized mice, though it was still insufficient to elicit serum IgA antibodies. Notably, the SARS-CoV virion itself was able to induce long-term antibody production even without an adjuvant. Anti-SARS-CoV antibodies elicited in mice recognized both the spike and nucleocapsid proteins of the virus and were able to neutralize the virus. Furthermore, the UV-inactivated virion induced regional lymph node T-cell proliferation and significant levels of cytokine production (IL-2, IL-4, IL-5, IFN-gamma and TNF-alpha) upon restimulation with inactivated SARS-CoV virion in vitro. Thus, a whole killed virion could serve as a candidate antigen for a SARS vaccine to elicit both humoral and cellular immunity. 相似文献
46.
Yozo MASUGI Yukinari MASUDA Shigeru SATO Masamichi ISHIZAKI Hiroshi SAWAGUCHI 《Pathology international》1983,33(2):219-236
Human renal biopsy specimens (472 cases) from varied kidney diseases, especially minimal glomerular change group and other idiopathic glomerular diseases having nephrotic manifestation of mainly juvenile individuals, showed morphologic evidence of paraarterial deposits of afferent arterioles at the glomerular entrances in more than 50% of examined cases. Because these deposits were often accompanied with concomitant mesangial, intraarterial and subendothelial deposits of afferent arterioles, it was felt that retarded mesangial transport which is ordinarily associated with certain glomerular diseases might be an important factor to produce these particular paraarterial deposits. The referred deposits of minimal glomerular change group cases were thought to predispose the occurrence of focal sclerotic capillary lesions at the vascular poles of glomeruli. The experimental chronic nephrotic rats produced by daily administration of aminonucleoside of puromycin revealed mesangial dysfunction with increased uptake and retarded disposal of secondarily overloaded aggregated human gamma globulin at mesangial areas in glomeruli. Besides, the increased deposits of autologous serum proteins in mesangial areas and arteriolar walls were common findings in those rats, and these deposits were observed to be always preceded to the occurrence of segmental sclerotic changes of glomeruli, which were often associated in the later stage of this experiment. ACTA PATHOL. JPN. 33: 219∼236, 1983. 相似文献
47.
48.
Miyake A Akagi T Enose Y Ueno M Kawamura M Horiuchi R Hiraishi K Adachi M Serizawa T Narayan O Akashi M Baba M Hayami M 《Journal of medical virology》2004,73(3):368-377
We have previously reported that concanavalin A-immobilized polystyrene nanospheres (Con A-NS) could efficiently capture HIV-1 particles and that intranasal immunization with inactivated HIV-1-capturing nanospheres (HIV-NS) induced vaginal anti-HIV-1 IgA antibody response in mice. In this study, to evaluate the protective effect of immunization, each three macaques was intranasally immunized with Con A-NS or inactivated simian/human immunodeficiency virus KU-2-capturing nanospheres (SHIV-NS) and then intravaginally challenged with a pathogenic virus, SHIV KU-2. After a series of six immunizations, vaginal anti-HIV-1 gp120 IgA and IgG antibodies were detected in all SHIV-NS-immunized macaques. After intravaginal challenge, one of the three macaques in each of the Con A-NS- and SHIV-NS-immunized groups was infected. Plasma viral RNA load of infected macaque in SHIV-NS-immunized macaques was substantially less than that in unimmunized control macaque and reached below the detectable level. However, it could not be determined whether intranasal immunization with SHIV-NS is effective in giving complete protection against intravaginal challenge. To explore the effect of the SHIV-NS vaccine, the remaining non-infected macaques were rechallenged intravenously with SHIV KU-2. After intravenous challenge, all macaques became infected. However, SHIV-NS-immunized macaques had lower viral RNA loads and higher CD4(+) T cell counts than unimmunized control macaques. Plasma anti-HIV-1 gp120 IgA and IgG antibodies were induced more rapidly in the SHIV-NS-immunized macaques than in the controls. The rapid antibody responses having neutralizing activity might contribute to the clearance of the challenge virus. Thus, SHIV-NS-immunized macaques exhibited partial protection to vaginal and systemic challenges with SHIV KU-2. 相似文献
49.
The relationships between increases in body mass index (BMI) and increases in hypertension were compared between non-drinkers with elevated serum gamma-glutamyl transpeptidase (gamma-GTP) levels (> or = 50 U/l) and those with normal levels, who comprised 10,952 men and 22,107 women aged 40-59 years recruited from an occupational health clinic. Hypertension was found in 16.1% and 13.5% of the men and women, and elevated serum g-GTP was found in 10.8% and 2.8% of the men and women, respectively. The prevalences of hypertension and elevated serum gamma-GTP levels were both increased with increased BMI. Hypertension was, however, shown to be 1.5 times more prevalent in the persons with elevated serum gamma-GTP levels than in those with normal levels in both sexes, even after adjusting for BMI by a multiple logistic analysis. It can be concluded that elevations of serum gamma-GTP, which are probably a reflection of fatty liver in the non-drinkers, are closely related to the development of hypertension associated with increased obesity. 相似文献
50.