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Soichiro Miura

Publications and source records attributed to Soichiro Miura.

At least 19 recordsLinked to original sources
PubMed2007

Involvement of transglutaminase-2 in pathological changes in renal disease.

BACKGROUND: Transglutaminase (Tg)-2 is shown to be related to renal fibrosis. However, its roles in human kidney disease have not been fully studied. METHODS: Using immunohistochemistry, we examined Tg-2 expression in renal biopsy specimens from 22 patients with IgA nephropathy (IgAN) and correlated the intensity of Tg-2 staining with clinical and histopathological parameters. We compared the distribution and intensity of Tg-2 staining with those of transforming growth factor (TGF)-beta staining. RESULTS: In normal human kidneys, Tg-2 staining was not significant. In IgAN kidneys, glomerular Tg-2 staining correlated with serum creatinine (S-Cr), creatinine clearance (Ccr), urinary protein excretion, glomerular sclerosis, and mesangial cell proliferation. Tubulointerstitial Tg-2 correlated with S-Cr, Ccr, N-acetyl-beta-glucosaminidase, urinary beta(2)-microglobulin, and tubulointerstitial injuries. Tg-2 staining in the vicinity of vascular poles of glomeruli preceded the development of mesangial lesions, and was more remarkable in cases with renal impairment. The distribution and intensity of Tg-2 staining were not consistent with those of TGF-beta staining. In glomerular crescents, Tg-2 staining was remarkable. CONCLUSION: The present study showed a correlation between Tg-2 expression and renal function and pathological changes. Tg-2 expression in the vicinity of vascular poles was notable because that may be an initial marker of glomerular injury.

Adult↗
PubMed2007

Significance of glomerular cell apoptosis in the resolution of acute post-streptococcal glomerulonephritis.

BACKGROUND: Glomerular hypercellularity due to resident glomerular cell proliferation and leucocyte infiltration has been described in acute post-streptococcal glomerulonephritis (APSGN). APSGN usually resolves without progression. However, the mechanism of resolution remains to be determined. METHODS: Renal biopsy tissues from 15 patients with APSGN (obtained 1-31 days after disease onset) and five control patients with minor glomerular abnormality were evaluated with respect to glomerular resolution. Apoptotic cells were assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labelling (TUNEL) as well as by immunostaining of single-stranded DNA (ssDNA). RESULTS: The number of glomerular cells was high in the early-phase of APSGN and decreased over time. No TUNEL+ glomerular cells were found in control subjects, whereas prominent glomerular TUNEL+ cells were observed in APSGN patients, particularly in the early phase of the disease. The number of glomerular TUNEL+ cells decreased exponentially but was still prominent in renal tissue biopsied at 31 days after disease onset. Double staining for ssDNA and glomerular cell markers showed that glomerular apoptotic cells were predominantly mesangium and endothelial cells, with some neutrophils and macrophages. CONCLUSIONS: These results suggest that apoptosis exists in the glomerulus in patients with APSGN from the early to the late stages of the disease and contributes to the resolution of glomerular hypercellularity.

Acute Disease↗
PubMed2006

Effect of risedronate on high-dose corticosteroid-induced bone loss in patients with glomerular disease.

BACKGROUND: Corticosteroids are often used for the treatment of glomerular diseases. We examined whether bisphosphonate or vitamin D3 has beneficial effects on bone mineral density (BMD) in patients with glomerular diseases being treated with high-dose corticosteroids, including pulse therapy. METHODS: Thirty-eight patients (19 men and 19 women, aged 42 +/- 16 years) were randomized into three groups: bisphosphonate alone (risedronate 2.5 mg/day, group R, n = 12), vitamin D3 alone (alfacalcidol 0.5 mug/day, group A, n = 15) and the combination of both agents (group R+A, n = 11). BMD at the lumbar spine was measured before and 12 months after treatment. The biochemical parameters of bone metabolism were assessed before and 3, 6 and 12 months after treatment. RESULTS: In group R+A, BMD was significantly increased (+2.0%), whereas BMD was significantly decreased in group A (-5.6%). The BMD in group R did not show a significant change. In patients treated with steroid-pulse, BMD was decreased in groups R and A. In group R+A, BMD was significantly increased (+2.1%). Serum osteocalcin and alkaline phosphatase levels, markers of bone formation, were significantly decreased in all groups. Urinary crosslinked N-telopeptide of type I collagen (NTx) levels, a marker of bone resorption, were decreased in groups R and R+A. In patients with decreased BMD, the urinary NTx levels at baseline were significantly higher than the patients with increased BMD. CONCLUSIONS: Bisphosphonate might be beneficial for the prevention of steroid-induced bone loss in patients with glomerular diseases compared with vitamin D3. The combined therapy may be more effective, especially in patients treated with high-dose corticosteroids, including pulse therapy. A high urinary NTx level before receiving corticosteroids might be a predictive marker of the loss of BMD.

Adolescent↗
PubMed2006

Activation of mouse natural killer T cells accelerates liver regeneration after partial hepatectomy.

BACKGROUND & AIMS: Activation of natural killer T cells with the synthetic ligand alpha-galactosylceramide (alpha-GalCer) induced hepatotoxicity through the tumor necrosis factor (TNF) and Fas-ligand-mediated pathway in aged mice. The aim of this study was to elucidate how alpha-GalCer-activated natural killer T cells function in hepatocyte proliferation and liver regeneration in partially hepatectomized (PHx) mice. METHODS: Mice were injected with alpha-GalCer at 36 hours after 70% PHx. Hepatocyte mitosis was evaluated by either mitotic figures or proliferating cell nuclear antigen staining. The role of TNF and Fas-ligand in hepatocyte mitosis also was assessed. RESULTS: In PHx mice injected with alpha-GalCer, hepatocyte mitosis was greatly enhanced at 44 hours after surgery and the increase was more obvious in aged mice than in young mice. The expression of both TNF receptor 1 and Fas-ligand in liver natural killer T cells tended to increase after alpha-GalCer injection in PHx mice. Treatment of mice with anti-NK1.1 Ab 3 days before and just after hepatectomy greatly inhibited the effect of alpha-GalCer on hepatocyte mitosis and liver regeneration. Furthermore, pretreatment of PHx mice with either anti-TNF Ab or anti-FasL Ab 1 hour before alpha-GalCer injection mostly abrogated the increase in hepatocyte proliferation. alpha-GalCer injection did not accelerate hepatocyte proliferation in Fas-mutated lpr mice after PHx. CD1d-/- mice without alpha-GalCer injection showed decreased hepatocyte mitosis after PHx. CONCLUSIONS: Activated natural killer T cells help hepatocyte proliferation and liver regeneration after PHx via the TNF and Fas/Fas-ligand-mediated pathway.

Animals↗
PubMed2006

Clinical response is associated with elevated plasma interleukin-1 receptor antagonist during selective granulocyte and monocyte apheresis in patients with ulcerative colitis.

Depletion of granulocytes and monocytes (GM) by selective apheresis (GMA) with an Adacolumn exerts an anti-inflammatory effect in patients with ulcerative colitis (UC) or rheumatoid arthritis. However, the mechanism of the anti-inflammatory effect of GMA is not fully understood yet. We investigated the effect of GMA on the plasma concentration of interleukin-1 receptor antagonist (IL-1ra), a potent anti-inflammatory cytokine. Twenty-six patients with active UC received GMA at one session per week for 5 consecutive weeks. Clinical response was defined as Deltaclinical activity index (DeltaCAI=CAI at entry - CAI at post)>or=4, while clinical remission was defined as CAI<or=4. Twenty-one of twenty-six patients (80.8%) responded to GMA. In the first session, plasma from responder patients showed a significant (P < 0.01) increase in IL-1ra in the Adacolumn outflow. In contrast, there was no change in IL-1ra in nonresponders. In conclusion, release of IL-1ra during GMA might be one mechanism of clinical efficacy associated with this therapy.

Adolescent↗
PubMed2006

BRAF mutation, CpG island methylator phenotype and microsatellite instability occur more frequently and concordantly in mucinous than non-mucinous colorectal cancer.

Mucinous colorectal cancer (CRC) has been reported to have distinct clinicopathological and genetic characteristics. However, the incidence and the relationship among microsatellite instability (MSI), CpG island methylator phenotype (CIMP) and BRAF and KRAS mutations in mucinous and non-mucinous CRC are not known. Activating mutations of BRAF and KRAS and their relationship with MSI and CIMP were examined in 83 sporadic CRC specimens (26 mucinous and 57 non-mucinous CRC). MSI, CIMP, BRAF and KRAS mutation were observed in 17, 24, 25 and 36% of the tumors, respectively. BRAF mutation was highly correlated with MSI (p < 0.001) and CIMP (p < 0.001). A higher incidence of MSI (27% vs. 12%), CIMP (38% vs. 18%, p < 0.05) and BRAF mutation (46% vs. 16%, p < 0.01) was observed in mucinous CRC. KRAS mutation (27% vs. 40%) was observed more frequently in non-mucinous CRC. Significantly higher percentages of mucinous CRC (54%, p < 0.05) had MSI or CIMP or BRAF mutations. Concordant occurrence of 2 or more of these alterations was observed in 39% of mucinous CRC and only 11% of non-mucinous CRC (p < 0.01). The more frequent occurrence and closer association among MSI, CIMP and BRAF mutation in mucinous CRC observed in our study further supports the idea that its pathogenesis may involve distinct genetic and epigenetic changes.

Adenocarcinoma, Mucinous↗
PubMed2006

Jumbo biopsy is useful for the diagnosis of colonic prolapsing mucosal polyps with diverticulosis.

We report here a case of multiple prolapsing mucosal polyps with diverticulosis in the sigmoid colon. A 52-year-old man was admitted to our hospital because of bloody diarrhea. Colonoscopy and barium enema showed multiple diverticula, markedly thickened mucosal folds and polypoid lesions with mucus on the top of them in the sigmoid colon. Endoscopic ultrasonography showed thickening of the mucosal and submucosal layers. Several endoscopic biopsy specimens were taken from the polypoid lesions. Histological examination revealed only chronic inflammatory cell infiltration. In order to obtain a definite diagnosis, we performed endoscopic jumbo biopsy for the polypoid lesions after obtaining informed consent. Histological examination revealed marked lymphocyte infiltration, hemosiderin deposits and fibromuscular obliteration in the lamina propria, features similar to those of mucosal prolapsing syndrome. After anti-diarrhetic treatment, clinical findings were improved. Thus, jumbo biopsy is useful for diagnosis and treatment of prolapsing mucosal polyps.

Biopsy↗
PubMed2006

Erythropoietin-induced proliferation of gastric mucosal cells.

AIM: To analyze the localization of erythropoietin receptor on gastric specimens and characterize the effects of erythropoietin on the normal gastric epithelial proliferation using a porcine gastric epithelial cell culture model. METHODS: Erythropoietin receptor was detected by RT-PCR, Western blotting and immunohistochermistry. Growth stimulation effects of erythropoietin on cultured gastric mucosal cells were determined by ELISA using bromodeoxyuridine (BrdU). RESULTS: Erythropoietin receptor was detected on cultured porcine gastric mucosal epithelial cells. Erythropoietin receptor was also detected histochemically at the base of gastric mucosal epithelium. BrdU assay demonstrated a dose-dependent increase in growth potential of cultured porcine gastric mucosal epithelial cells by administration of erythropoietin, as well as these effects were inhibited by administration of anti- erythropoietin antibody (P<0.01). CONCLUSION: These findings indicate that erythropoietin has a potential to proliferate gastric mucosal epithelium via erythropoietin receptor.

Animals↗
PubMed2006

Differential modulation in the functions of intestinal dendritic cells by long- and medium-chain fatty acids.

BACKGROUND: Although dendritic cells (DCs) play significant roles in intestinal immune responses, little is known regarding the direct effects of luminal foods on DC functions in the intestinal mucosa. In this study, we examined the effects of fatty acids (FAs) with various chain length on the phagocytic function, antigen presentation, and chemotaxis of intestinal DCs. METHODS: DCs obtained from the thoracic duct lymph of mesenteric lymphadenectomized rats were cultured with long [arachidonic acid (AA) or oleic acid] or medium (octanoic acid) chain FAs with interleukin-4 and granulocyte macrophage-colony stimulating factor. Tumor necrosis factor-alpha was added in the maturation group. Phagocytic function was examined by the intake of fluorescent microbeads. The expression of cell surface molecules was determined by immunocytochemistry or fluorescence-activated cell sorting (FACS). Antigen presentation ability was evaluated by coincubating keyhole limpet hemocyanin (KLH)-sensitized spleen lymphocytes and KLH-pulsed DCs. Migratory ability of DCs toward the chemokines CC chemokine ligand (CCL) 20 and CCL21 was also assessed. RESULTS: There was a maturation-induced decrease in phagocytic function, and an increased expression of major histocompatibility complex (MHC) class II molecules. Exposure of DCs to both long- and medium-chain FAs maintained phagocytic ability. The expression of MHC class II molecules was significantly suppressed only by long-chain FAs. The expression of costimulatory factors was suppressed only by AA. Long- but not medium-chain FAs suppressed the antigen presentation ability of DCs induced by maturation. Chemotactic ability of mature DCs toward CCL21 was abrogated only by long-chain FAs. CONCLUSIONS: The data suggest that intraluminal exposure to long- and medium-chain FAs may differentially modulate the immune functions of intestinal DCs.

Animals↗
PubMed2006

Impact of hypertension and hypertension-related vascular lesions in IgA nephropathy.

It remains poorly understood whether vascular pathology plays an important role in the progression of renal parenchymal disease in humans. Moreover, in the case of hypertensive patients with mild proteinuria, nephrologists tend to make a diagnosis of benign nephrosclerosis without renal biopsy. Among 172 patients who were treated at our hospital for biopsy-proven IgA nephropathy, we performed quantitative histopathological analysis in 38 patients with mild proteinuria of less than 0.5 g/day. We related these histopathological parameters with clinical data at biopsy and also with follow-up data. The percentage of glomeruli showing global sclerosis exceeded 10% of total glomeruli in 15 of the patients (39.5%) and exceeded 20% in 9 (23.7%). Arteriosclerosis and tubulointerstitial changes significantly correlated with glomerular sclerosis, but mesangial cell proliferation did not. Among the 38 patients, the 12 with hypertension showed more severe glomerular sclerosis, tubulointerstitial changes and arteriosclerosis compared with the 26 without hypertension, but the mesangial cell proliferation was identical between the two groups. Stepwise multiple regression analysis revealed that hypertension and urinary protein excretion (UPE) were independent risk factors for arteriosclerosis. The follow-up data of a mean period of 27.6 months showed that 9 of the 38 patients (23.7%) had an increase in UPE. Hypertension, arteriosclerosis, age, and UPE at biopsy were selected as the important risk factors for an increase in UPE in the follow-up. Our results provide not only clinical but histopathological evidence that hypertension affects the prognosis of mild proteinuric nephropathy through vascular lesions.

Adolescent↗
PubMed2006

Attenuating effect of Myakuryu on mesenteric microcirculatory disorders induced by ischemia and reperfusion.

Myakuryu (MR) is a newly developed herbal medicine composing Crataegue oinnatifida bge (COB), Panax notoginseng (PN) and Ginkyo biloba (GB). To examine the effectiveness of MR, we investigated its effects on rat mesenteric microcirculatory injury induced by ischemia/reperfusion (I/R). The mesenteric microcirculation of ileocecal portion of a male Wistar rat was observed through an inverted-type intravital microscope assisted with a charge-coupled devise (CCD) camera. Mesenteric I/R was conducted by a ligation of the mesenteric artery and vein (10 min) and subsequent release of the occlusion. We measured venular diameter, the number of adherent leukocytes, dihydrorhodamine 123 (DHR) fluorescence as an indicator of oxidative stress and mast cell degranulation, with or without MR extract (0.4 g/kg b.w.) via an orogastric tube 1 hr before I/R. The diameters of the observed mesenteric venules were not changed after the mesenteric I/R. MR had no effect on venular diameter. The leukocytes adhering to the post-capillary venular walls started just after reperfusion, and increased thereafter. The increased number of adherent leukocytes was significantly reduced by treatment with MR. DHR fluorescence ratio was significantly increased along the venular wall. MR attenuated the increased oxidation. The mesenteric I/R induced mast cell degranulation. The increase in mast cell degranulation was inhibited by MR. In conclusion, oral administration of MR attenuates I/R-induced microvascular damages in rat mesentery. MR has a therapeutic potential for prevention of I/R-related microvascular injury.

Animals↗
PubMed2006

MUC5AC mucin gene regulation in pancreatic cancer cells.

MUC5AC is a secretory mucin normally expressed by the surface mucous cells of the human stomach and in the bronchial tract. It is absent from normal pancreas, but de novo expression of this mucin occurs in early-stage pancreatic intraepithelial neoplasias and in the invasive ductal adenocarcinoma of the pancreas, prompting this study of MUC5AC gene regulation in pancreatic cancer cells. Promoter deletion constructs and EMSA studies revealed that transcription factors Sp1 and AP-1 are both involved in basal transcription of the MUC5AC gene. Phorbol 12-myrisate 13-acetate (PMA) increased MUC5AC mRNA expression and transcriptional activities of MUC5AC promoter-reporter deletion constructs containing AP-1 consensus sites. EMSA studies showed that Fos/Jun binding to putative AP-1 sites is increased by PMA treatment. Western blot analysis showed that ERK, JNK and p38 are all activated by PMA treatment in SW1990 cells. Inhibitors of mitogen-activated protein/extracellular signal regulated kinase (MEK), such as ERK inhibitor PD98059 and JNK inhibitors dicumarol and SP60015, but not p38 inhibitor SB203580, inhibited PMA-induced MUC5AC reporter activity. Our studies indicate that Sp1 is involved in basal MUC5AC promoter activity while AP-1 is involved in basal and PMA-induced MUC5AC promoter activation in pancreatic cancer cells. Furthermore, PMA-induced MUC5AC gene transcription appears to be mediated by activating Sp1, PKC/ERK/AP-1 and PKC/JNK/AP-1 pathways.

Carcinoma, Pancreatic Ductal↗
PubMed2006

[Antagonists of the type 3 serotonin receptor (5 -HT3) in IBS].

Irritable bowel syndrome (IBS) is a common chronic gastrointestinal (GI) disorder, but its pathophysiology remains unknown. 5-hydroxytryptamine (5-HT, serotonin) is an important neurotransmitter involved in the brain-gut connection. Alosetron, a 5-HT3 receptor antagonist, has been demonstrated in randomized, placebo-controlled trials (RCT) to be effective in diarrhea-predominant IBS(IBS-D). Constipation is the most common adverse event. Alosetron improved abdominal pain and discomfort and stool consistency in both female and male patients, but it did not improve other symptoms (sense of urgency, stool frequency and bloating) in male patients. Although less is known about the gender differences in therapeutic benefit, a new 5-HT3 antagonist, cilansetron, has demonstrated effectiveness in male and female IBS-D patients and is currently under clinical trials.

Carbazoles↗
PubMed2006

[A case of Churg-Strauss syndrome discovered with hematemesis].

A 68-years-old Japanese woman was hospitalized emergently because of hemorrhagic gastric ulcer. For the hospitalization period, elevated levels of white blood cell count, eosinophilic leucocyte count, serum IgE and positive MPO-ANCA were recognized. With considering clinical course and these laboratory findings, we diagnosed Churg-Strauss syndrome (CSS). Steroid therapy in combination with cyclophosphamide was effective. CSS is a rare disease, but we should discriminate this disease when we encounter gastrointestinal bleeding of unknown etiology, especially PPI-resistant gastric ulcer.

Aged↗