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51.
Nobuo Tsuda Paritosh Roy Chowdhury Tomayoshi Hayashi Masanobu Anami Masachika Iseki Shigehiko Koga Fukuzo Matsuya Hiroshi Kanetake Yutaka Saito Yoshio Horita 《Pathology international》1997,47(11):778-783
Primary renal angiosarcoma is very rare. To our knowledge, only 15 cases have been reported to date. A 77-year-old Japanese man with a unilateral kidney presented with massive hematuria followed by renal failure. A renal tumor was suspected and a left nephrectomy was performed. The histopathological diagnosis was angiosarcoma of the kidney. A hemorrhagic tumor measuring 10 × 5 cm and clotted blood was found in the modularly area. The atypical tumor cells had a sinusoidal and solid appearance, and showed Immunohistochemically positive reactions for some of the endothelial markers. The patient died about 21 months after the nephrectomy and the autopsy revealed massive metastases to the liver and retroperitoneum. One of the differential diagnoses of the case was anglomyolipoma, because the tumor cells were relatively bland in their histological appearance with entrapped fat cells in the pelvic area. Fifteen case reports with titles that included the term 'hemangiosarcoma/anglosarcoma', 'hemangioendothelloma/endothelloma' or 'vascular sarcoma' of the kidney were reviewed and compared to the present case. 相似文献
52.
Biochemical and immunobiological properties of lipopolysaccharide (LPS) from Bacteroides gingivalis and comparison with LPS from Escherichia coli. 总被引:3,自引:14,他引:3
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T Koga T Nishihara T Fujiwara T Nisizawa N Okahashi T Noguchi S Hamada 《Infection and immunity》1985,47(3):638-647
Lipopolysaccharides (LPSs) were isolated from Bacteroides gingivalis and Escherichia coli by the phenol-water and butanol-water procedures. The phenol-water-extracted LPS from B. gingivalis 381 was composed of 46% carbohydrate, 23% hexosamine, 18% fatty acid, and 5% protein. The major component sugars of this preparation were glucose, glucosamine, rhamnose, galactose, galactosamine, and mannose, and their molecular ratio was 1:0.9:0.7:0.6:0.6:0.4, respectively. Neither heptose nor 2-keto-3-deoxyoctonate was detected. The butanol-water-extracted LPS from this strain was composed of 76% glucose, 7% fatty acid, and 13% protein, and it was associated with a number of polypeptides (13 to 56 kilodaltons). The main fatty acid of both LPS preparations was palmitic acid. It was found that biological activities of LPS from B. gingivalis were comparable to those of LPS from E. coli in terms of activation of the clotting enzyme of Limulus amebocyte lysate, mitogenicity, polyclonal B cell activation, and stimulation of interleukin 1 production in BALB/c mice. Furthermore, LPS-nonresponsive C3H/HeJ spleen cells were found to yield good mitogenic responses to both phenol-water-extracted LPS and butanol-water-extracted LPS from B. gingivalis or butanol-water-extracted LPS from E. coli. On the other hand, spleen cells from LPS-responsive C3H/HeN mice responded well to all these LPS preparations. 相似文献
53.
Koga K Osuga Y Tsutsumi O Okagaki R Momoeda M Yano T Fujiwara T Takai Y Kugu K Morita Y Taketani Y 《Molecular human reproduction》2000,6(10):929-933
Tumour necrosis factor alpha (TNFalpha), a proapoptotic cytokine, is known to be present in peritoneal fluid from women with endometriosis. An emerging view is that soluble TNF receptors (sTNFR) can modulate the effects of TNFalpha by acting as TNFalpha antagonists. To assess the relevance of sTNFRs in the pathophysiology of endometriosis, concentrations of sTNFR I, sTNFR II and TNFalpha in peritoneal fluid from women with endometriosis (n = 53) and without endometriosis (n = 40) were measured. Concentrations of both sTNFR I and sTNFR II in peritoneal fluid from women with endometriosis were significantly higher than in peritoneal fluid from women without endometriosis, both in the follicular and the luteal phases. TNFalpha concentrations did not differ in patients with and without endometriosis in both phases. When stratified by the stage of the disease, women with both stages I/II and stages III/IV exhibited significantly higher concentrations of sTNFR I and sTNFR II in peritoneal fluid, compared with women without endometriosis, whereas no appreciable difference in the concentrations was detected between stages I/II and stages III/IV. A significant correlation was found between the concentrations of sTNFR I and sTNFR II; while the correlations between TNFalpha and sTNFR I or sTNFR II, were either not significant or were very weak. Furthermore, mRNA for the membrane-associated TNF receptor type 1 and TNF receptor type 2, both of which convey the effects of TNFalpha, were shown to be expressed in endometriotic tissues as well as eutopic endometrium. Together, these findings suggest a possible involvement of sTNFRs in the pathophysiology of endometriosis. 相似文献
54.
Utsugi M Dobashi K Koga Y Shimizu Y Ishizuka T Iizuka K Hamuro J Nakazawa T Mori M 《Journal of leukocyte biology》2002,71(2):339-347
We examined whether changes in intracellular reduced (GSH) or oxidized (GSSG) glutathione of human monocytes regulate lipopolysaccharide (LPS)-induced IL-12 production and defined the molecular mechanism that underlies glutathione redox regulation. Monocytes exposed to glutathione reduced form ethyl ester (GSH-OEt) or maleic acid diethyl ester (DEM) increased or decreased the intracellular GSH/GSSG ratio, respectively. LPS-induced IL-12 production and p38 mitogen-activated protein (MAP) kinase activation were enhanced by GSH-OEt but suppressed by DEM. Selective p38 inhibitors showed that p38 promoted GSH-OEt-enhanced IL-12 production. Furthermore, IFN-gamma priming increased the GSH/GSSG ratio and enhanced IL-12 production through p38, and DEM negated the priming effect of IFN-gamma on p38 activation and IL-12 production as well as on the GSH/GSSG ratio. These findings reveal that glutathione redox regulates LPS-induced IL-12 production from monocytes through p38 MAP kinase activation and that the priming effect of IFN-gamma on IL-12 production is partly a result of the glutathione redox balance. 相似文献
55.
Koga H Sakisaka S Yoshitake M Harada M Kumemura H Hanada S Taniguchi E Kawaguchi T Kumashiro R Sata M 《International journal of molecular medicine》2002,9(6):621-626
Primary sclerosing cholangitis (PSC) is known to be frequently associated with inflammatory bowel diseases. In a rat with self-filling blind loop (SFBL), a proposed animal model for PSC, hepatobiliary inflammation has previously been demonstrated. In this study, we assessed the involvement of lipopolysaccharide (LPS), a bacterial endotoxin, in the pathogenesis of hepatobiliary inflammation of the SFBL model. The hepatic localization of LPS was examined by immunohistochemistry using an anti-lipid A antibody. The portal blood concentration of LPS was measured by an endotoxin-specific chromogenic Limulus test (Endospecy test). LPS was localized in the biliary epithelial cells (BECs) of rats with SFBL, and the portal blood concentration of LPS was significantly higher than that of sham-operated rats. Development of hepatobiliary inflammation, peribiliary fibrosis, and injury to the intestinal mucosa were histologically confirmed. Constriction in the biliary trees was radiologically demonstrated. These findings suggested that abnormal accumulation of LPS, which may be derived from portal blood, in BECs was involved in the pathogenesis of hepatobiliary inflammation with intestinal injury. 相似文献
56.
Sakaguchi M Kubota S Nishikido M Taniguchi K Inuzuka S Saito Y Kanetake H Koga S 《International journal of molecular medicine》2002,10(3):317-320
The nature of effectors of interferon (IFN)-alpha or IFN-gamma-induced killer cell activity remains unclear. The aim of this study was to examine killer cell activity induced by IFN-alpha alone, IFN-gamma alone or a combination of both in patients with renal cell carcinoma (RCC) and to determine the phenotypic patterns of these effectors. The study group included 14 patients (12 men and 2 women, median age 64 years, range 36-77) with confirmed RCC. Peripheral blood mononuclear cells (PBMC) from RCC patients or normal volunteers were cultured with IFN-alpha alone, IFN-gamma alone or a combination of both. Cytotoxic activity was assayed against ACHN cells. Subpopulations of effector cells in IFN-induced killer cell activity were characterized by cell sorting. The most effective type of IFN and the optimal concentration of IFN necessary to induce the maximal killer cell activity varied among RCC patients. The killer activity induced by a combination of IFN-alpha and IFN-gamma was significantly greater than that induced by IFN-alpha or IFN-gamma alone. The greatly increased killer activity induced by IFN-alpha and IFN-gamma was seen in the subpopulations CD3(-) CD16(+), CD3(-) CD56(+) and subpopulation CD3(+)CD4(-), CD3(-)CD16(+), CD3(-)CD56(+), CD57(+)CD16(-), respectively. An optimal type of IFN and optimal concentration of IFN seem to increase the effective rate of treatment of RCC. In addition, the role of IFN-alpha seems to be different from that of IFN-gamma in host defense against RCC. A combination treatment with IFN-alpha and IFN-gamma seems to be suitable to increase the effective rate if we could reduce the side effects of IFNs. 相似文献
57.
Sudo N Aiba Y Oyama N Yu XN Matsunaga M Koga Y Kubo C 《International archives of allergy and immunology》2004,135(2):132-135
BACKGROUND: Intestinal microbiota are known to play an important role in the establishment of oral tolerance, thereby protecting the organism from food allergies. Dietary intake of nucleic acid (NA) is also reported to have such an anti-allergic effect; however, one unsolved question is whether or not dietary NA would act through a process of toll-like receptor 9 signaling activated by DNA containing a CpG motif, a well-known sequence leading to immunostimulatory activity. In this study, we focused on the question of whether the addition of dietary NA lacking CpG motifs would allow continued modulation of the Th1/Th2 balance. METHODS: Germ free (GF) and Bifidobacterium-infantis-monoassociated BALB/c mice were maintained on either an NA-free casein diet or on an NA-supplemented casein diet for 4 weeks. Thereafter, both the in vivo anti-casein antibody levels and in vitro splenocyte cytokine secretion pattern were evaluated. RESULTS: Feeding with a casein diet elicited a substantial increase in the serum anti-casein-specific IgG1, IgG2a, and IgE levels of GF mice fed the NA free-diet. The in vitro cytokine production profile showed that enhanced IL-4 production in the GF mice fed the NA free-diet was markedly reduced by the supplementation with dietary NA in both the GF and B.-infantis-monoassociated mice. In addition, IFN-gamma secretion increased in the B.-infantis-reconstituted mice fed the diet containing NA. CONCLUSIONS: These results suggest that dietary intake of NA devoid of CpG motifs may prevent the development of allergies via acceleration of Th1-dominant immunity. 相似文献
58.
Changes in the number of activated sweat glands (ASGs) and sweat output per gland (SGO) with increased exercise intensity during sustained static exercise were investigated. Fourteen male subjects performed 20, 35, and 50% maximal voluntary contraction (MVC) for 60 s with the right hand (exercised arm) at an ambient temperature of 35 degrees C and 50% relative humidity. Although sublingual, local skin, and mean skin temperatures remained essentially constant throughout the exercise at each intensity, the sweating rate (SR) of nonglabrous skin on the nonexercised left forearm increased significantly with a rise in exercise intensity (p<0.05). Changes in the number of ASGs with rising exercise intensity paralleled changes in the SR, but the SGO did not change markedly with altered exercise intensity. These results suggest that in mildly heated humans, at less than 50% MVC, the increase in the SR from nonglabrous skin with rising exercise intensity during sustained static exercise is dependent on changes in the number of ASGs and not on SGO. 相似文献
59.
Gender-specific haplotype association of collagen α2 (XI) gene in ossification of the posterior longitudinal ligament of the spine 总被引:5,自引:0,他引:5
Maeda S Koga H Matsunaga S Numasawa T Ikari K Furushima K Harata S Takeda J Sakou T Komiya S Inoue I 《Journal of human genetics》2001,46(1):1-4
Among Japanese, ossification of the posterior longitudinal ligament of the spine (OPLL) is a leading cause of myelopathy,
showing ectopic bone formation in the paravertebral ligament. We have provided genetic evidence that the collagen α2 (XI)
(COL11A2) locus of chromosome 6 constitutes susceptibility for OPLL. Five distinct single nucleotide polymorphisms (SNPs), identified
in COL11A2, were combined to construct possible haplotypes by the use of a maximum likelihood program. Estimated haplotype frequency
was compared in OPLL patients and non-OPLL controls. We report a gender-specific association of the COL11A2 haplotype with OPLL. The frequency of the most commonly observed haplotype was significantly higher in male patients (P = 0.0003) compared with controls, but not in female patients (P = 0.21). OPLL is predominantly observed in males, with a prevalence ratio of 2 : 1, and our gender-specific associations
indicate that genetic factors involving COL11A2 play a specific role in the etiology of OPLL exclusively in males.
Received: September 5, 2000 / Accepted: October 2, 2000 相似文献
60.
N Koga J Kuroki H Nakashima Y Hokama-Kuroki H Yoshimura H Kuroki Y Masuda 《Fukuoka igaku zasshi》1991,82(5):197-206
Acute toxicity, inductive effects of liver enzymes and liver persistency of 1,2,3,7,8-pentachlorodibenzo-p-dioxin (PenCDD) were compared with those of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) using male Wistar rats. 1,2,3,7,8-PenCDD treatment at a dose of 0.1 mumol/kg resulted in significant depression of growth of rats from a day to 28 days after treatment. However, the effect was relatively less than that of 2,3,7,8-TCDD. On 5 days, similarly to 2,3,7,8-TCDD-treated group, liver hypertrophy and thymic atrophy were observed in 1,2,3,7,8-PenCDD-treated groups. In addition, 1,2,3,7,8-PenCDD showed potent 3-methylcholanthrene-type inducing ability. For example, the activities of benzo(a)pyrene 3-hydroxylase and DT-diaphorase were 25-fold and 10-fold of control, respectively. On 30 days, about 50% of the inductive effects on 5 days were maintained in both 1,2,3,7,8-PenCDD- and 2,3,7,8-TCDD-treated groups. Amount of 1,2,3,7,8-PenCDD distributed to the liver on 5 days was about 80-90% of dose and was about 1.5 times greater than that of 2,3,7,8-TCDD. About 50% of dose of 1,2,3,7,8-PenCDD remained even on 30 days after treatment. From these results, it is suggested that 1,2,3,7,8-PenCDD possessing the potent acute toxicity comparable to 2,3,7,8-TCDD and higher persistency in the liver might be more important than 2,3,7,8-TCDD in terms of the chronic toxicity. 相似文献