Seiji Yamaguchi
Osaka University
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Urological Research | 1993
Seiji Yamaguchi; Toshiaki Yoshioka; Masato Utsunomiya; Takuo Koide; Masao Osafune; Akihiko Okuyama; Takao Sonoda
SummaryThe nature of the soluble stone matrix and its possible role in urinary stone formation was studied. For this purpose we performed two-dimensional cellulose acetate membrane electrophoresis of the glycosaminoglycans (GAGs) which were contained in the soluble stone matrix, substances adsorbed onto calcium oxalate crystals in vitro (crystal surface binding substances, CSBS) and urinary macromolecules (UMMs). The main GAG in the soluble stone matrix and CSBS was found to be heparan sulfate, whereas the UMMs contained various GAGs usually seen in urine. An inhibition assay showed the soluble stone matrix to have the strongest inhibitory activity among these macromolecular substances when inhibitory activity was expressed in terms of uronic acid concentration. It is suggested that the main GAG in the soluble stone matrix consists of heparan sulfate, which has a strong inhibitory activity on calcium oxalate crystal growth and aggregation and constitutes part of the CSBS.
The Journal of Urology | 2011
Kazutoshi Fujita; Masahiro Hosomi; Go Tanigawa; Masayoshi Okumi; Hiroaki Fushimi; Seiji Yamaguchi
PURPOSEnAsymptomatic prostatic inflammation may cause increased prostate specific antigen in some men, leading to unnecessary repeat prostate biopsy. We determined whether histological findings of inflammation in initial biopsy specimens and/or clinical indicators of inflammation could predict the outcome of subsequent biopsy in men with a negative initial biopsy.nnnMATERIALS AND METHODSnA total of 105 Japanese men with increased prostate specific antigen underwent repeat prostate biopsy after initial biopsy revealed no evidence of carcinoma. Of the cases 45 (42.8%) were positive for prostate cancer at repeat biopsy. We evaluated initial biopsy specimens for evidence of inflammation by mononuclear and polymorphonuclear leukocytes, serum and urinary white blood count, and C-reactive protein.nnnRESULTSnPolymorphonuclear leukocyte infiltrates, urinary white blood count, patient age, prostate specific antigen at repeat biopsy, prostate volume, prostate specific antigen velocity and prostate specific antigen density were associated with the repeat biopsy outcome (p <0.05). Multivariate analysis revealed that age, prostate specific antigen density and urinary white blood count were independent predictors of outcome. On subgroup analysis of 63 men with serum prostate specific antigen less than 10 ng/ml before initial biopsy polymorphonuclear and mononuclear leukocyte inflammation, age, prostate specific antigen at repeat biopsy, prostate volume, prostate specific antigen velocity and prostate specific antigen density were associated with the outcome of repeat biopsy (p <0.05). Multivariate analysis showed that polymorphonuclear leukocyte infiltrate, prostate specific antigen density and age were independent predictors.nnnCONCLUSIONSnAge, prostate specific antigen density, polymorphonuclear leukocyte inflammation in initial biopsy specimens and urinary pyuria are indicators of benign repeat biopsy. They help avoid unnecessary repeat biopsy in men with increased prostate specific antigen.
Urological Research | 1990
Takuo Koide; Toshiaki Yoshioka; Seiji Yamaguchi; S. Hosokawa; Masato Utsunomiya; Takao Sonoda
SummaryIn order to study the effect of urinary crystal surface binding substances (CSBS), we extracted the naturally existing CSBS from urine from healthy individuals by conducting homogeneous crystallization of calcium oxalate. CSBS proved not to be promoters but rather strong inhibitors of calcium oxalate crystal growth and aggregation. It is suggested that CSBS exhibited their inhibitory effect by masking the growing sites and aggregating sites on the crystal surface. As for the characteristics of CSBS, we found around 10 peaks of molecular weight, and all of them contained both peptides and saccharides. The findings suggest that CSBS are composed of various kinds of glycoproteins and proteoglycans.
Urological Research | 1997
Masahito Honda; Toshiaki Yoshioka; Seiji Yamaguchi; Kazuhiro Yoshimura; Osamu Miyake; Masato Utsunomiya; Takuo Koide; Akihiko Okuyama
We previously extracted crystal surface binding substance (CSBS) from human urine and showed that it appeared to constitute a substantial proportion of urinary macromolecular inhibitors of calcium oxalate crystallization. CSBS was isolated from human urine and fractionated by three consecutive chromatography procedures in order to characterize protein inhibitors of calcium oxalate crystallization. Sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and NH2-terminal amino acid sequencing revealed that inhibitory fractions eluted from a final, hydroxyapatite column contained prothrombin and osteopontin. Hydroxyapatite column fractions also contained other, unidentified protein inhibitors of calcium oxalate crystallization. CSBS contained also human serum albumin, α1-acid glycoprotein, α2-microglobulin, α2-HS glycoprotein, retinol-binding protein, transferrin, and Tamm-Horsfall protein, but these proteins seemed to play no direct role in inhibitory activity.
Urology | 1992
Kiyomi Matsumiya; Yoshio Kanayama; Seiji Yamaguchi; Yuya Ueyama; Masayuki Iwasaki; Masao Osafune
An extramedullary plasmacytoma (EMP) is presented with an isolated lesion in the urinary bladder accompanying an IgG-K paraproteinemia. After a short-term oral melphalan administration, the tumor soon regressed together with the paraprotein, and has never recurred during the two-year follow-up. This is the fourth case of primary EMP of the urinary bladder reported in the literature.
The Journal of Urology | 1992
Takuo Koide; Toshiaki Yoshioka; Seiji Yamaguchi; Masato Utsunomiya; Takao Sonoda
Simple mechanical disintegration of cystine calculi by extracorporeal shock wave lithotripsy and/or percutaneous nephrolithotomy is being performed widely around the world. However, it cannot be denied that the cystine calculus is one of the most difficult stones for mechanical disintegration. We previously reported the oral medical chemolysis of cystine calculi in 1982 and a third of the patients became stone-free. In another third of the patients the cystine component was replaced by apatite during the medical treatment and apatite stones formed in this manner are easily disintegrated. In view of the complications of mechanical disintegration, oral medical treatment for chemolysis should be recommended before simple destruction of cystine calculi.
Cancer Biology & Therapy | 2016
Eiji Kashiwagi; Kazutoshi Fujita; Seiji Yamaguchi; Hiroaki Fushimi; Hiroki Ide; Satoshi Inoue; Taichi Mizushima; Leonardo Oliveira Reis; Rajni Sharma; George J. Netto; Norio Nonomura; Hiroshi Miyamoto
ABSTRACT To assess the expression status of steroid hormone receptors in upper urinary tract urothelial carcinoma (UUTUC), we immunohistochemically stained for androgen receptor (AR), estrogen receptor-α (ERα), ERβ, glucocorticoid receptor (GR), and progesterone receptor (PR) in 99 UUTUC specimens and paired non-neoplastic urothelial tissues. AR/ERα/ERβ/GR/PR was positive in 20%/18%/62%/63%/16% of tumors, which was significantly lower (except PR) than in benign urothelial tissues [57% (P < 0.001)/40% (P = 0.001)/85% (P = 0.001)/84% (P = 0.002)/13% (P = 0.489)]. There were no significant associations between each receptor expression pattern and histopathological characteristic of the tumors including tumor grade/stage. Kaplan-Meier and log-rank tests revealed no significant prognostic value of each receptor expression in these 99 patients. However, patients with UUTUC positive for either ERα or PR had a significantly higher risk of disease-specific mortality (P = 0.025), compared with those with UUTUC negative for both. PR positivity alone in pT3 or pT4 tumors was also strongly associated with the risk of disease-specific mortality (P = 0.040). Multivariate analysis further identified the expression of ERα and/or PR as a strong predictor for disease-specific mortality in the entire cohort of the patients (hazard ratio, 2.434; P = 0.037). Thus, in accordance with previous observations in bladder specimens, significant decreases in the expression of AR/ERα/ERβ/GR in UUTUC, compared with that in non-neoplastic urothelium, were observed. Meanwhile, the negativity of both ERα and PR in UUTUC as well as the negativity of PR alone in deeply invasive tumor was suggested to serve as a prognosticator.
Human Pathology | 2017
Satoshi Inoue; Taichi Mizushima; Kazutoshi Fujita; Abdelrazak Meliti; Hiroki Ide; Seiji Yamaguchi; Hiroaki Fushimi; George J. Netto; Norio Nonomura; Hiroshi Miyamoto
Immunohistochemistry of a transcription factor, GATA3, has been widely used as a promising urothelial marker in diagnostic surgical pathology practice. However, the expression status of GATA3 in upper urinary tract urothelial carcinomas (UUTUCs) and its prognostic significance have not been fully investigated. We immunohistochemically stained for GATA3 in 99 UUTUC samples and paired nonneoplastic urothelial tissues. GATA3 was positive in 51 (51.5%; 32 [32.3%] weak, 11 [11.1%] moderate, 8 [8.1%] strong) of 99 UUTUCs, which was significantly lower than in benign urothelium (79 [96.3%] of 82; 33 [40.2%] weak, 35 [42.7%] moderate, 11 [13.4%] strong; P<.001). However, there were no statistically significant associations between GATA3 expression and tumor grade, pT stage, lymph node involvement, or distant metastasis. Meanwhile, the rate of GATA3 positivity was significantly higher (P=.004) in ureteral tumors (66.0%) than in renal pelvic tumors (35.6%). Kaplan-Meier and log-rank tests revealed that GATA3 negativity was significantly associated with lower recurrence-free survival (P=.037 for all cases, P=.026 for muscle-invasive tumors) and cancer-specific survival (P=.007 for all cases, P=.012 for muscle-invasive tumors, P=.035 for cases with adjuvant chemotherapy) rates. Multivariate analysis further identified strong correlations of GATA3 expression with tumor progression (all cases: hazard ratio [HR], 0.479 [95% confidence interval {CI},0.229-1.003; P=.051]; muscle-invasive tumors: HR, 0.387 [95% CI, 0.166-0.903; P=.028) or cancer-specific mortality (all cases: HR, 0.354 [95% CI, 0.135-0.925; P=.034]; muscle-invasive tumors: HR, 0.402 [95% CI, 0.149-1.086; P=.072]). Thus, compared with nonneoplastic urothelium, a significant decrease in the expression of GATA3 in UUTUC was seen. Moreover, loss of GATA3 expression was found to be an independent predictor of poor patient outcomes. Of note was that only roughly half of high-grade and/or muscle-invasive UUTUCs were immunoreactive for GATA3.
Archive | 1994
Takuo Koide; Masato Utsunomiya; Seiji Yamaguchi; Toshiaki Yoshioka
We have already demonstrated the effectiveness of tiopronin (α-mercaptopropionylglycine, Thiola®,) for cystine stone dissolution and for preventing stone formation in cystinuric patients1. Thiol compounds, such as D-penicillamine, tiopronin and captopril convert urinary cystine by a mixed disulfide exchange reaction, into a cysteine complex which is more soluble than cystine. Therefore, thiol compounds can dissolve cystine stones and effectively prevent cystine stone formation. Bucillamine (2-mercapto-2-methylpropanoyl-L-cysteine), which is a new therapeutic agent for rheumatoid arthritis, having been used for the last 5 years in Japan2, is a dithiol compound, while tiopronin and D-penicillamine are monothiol compounds (Fig. 1). Approximately 40% of bucillamine given per os is excreted into urine as various metabolites. Three major metabolites have been identified. About 10% of bucillamine appeared in urine as a non-metabolized free form and about 15% as a metabolized monothiol compound3. A small amount appeared as a metabolized non-thiol compound. Theoretically, bucillamine is a more effective medicine for cystinuria than tiopronin, because of its number of thiol groups. We studied the effect of bucillamine on urinary cystine both in vitro and in vivo clinical trials and compared the result with that of tiopronin in this study.
Translational Oncology | 2017
Takashi Kawahara; Satoshi Inoue; Kazutoshi Fujita; Taichi Mizushima; Hiroki Ide; Seiji Yamaguchi; Hiroaki Fushimi; Norio Nonomura; Hiroshi Miyamoto
We recently found that NFATc1, a member of the NFAT family and a key regulator of the immune response, could induce bladder carcinogenesis and cancer progression. In this study, we immunohistochemically stained for NFATc1 in upper urinary tract urothelial carcinoma (UUTUC) specimens and paired nonneoplastic urothelial tissues. NFATc1 was positive in 51 [52%; 40 (40%) weak (1+), 9 (9%) moderate (2+), and 2 (2%) strong (3+)] of 99 UUTUCs, which was significantly higher than in benign urothelium [30 (36%) of 83; 28 (34%) weak and 2 (2%) moderate] (0 vs 1+/2+/3+, P = .038; 0/1+ vs 2+/3+, P = .023). There were no significant associations between NFATc1 expression pattern and tumor grade or pT stage. However, the positive rates of NFATc1 expression tended to be higher in renal pelvic tumors (60%) than in ureteral tumors (42%; P = .080) as well as in pN+ tumors (75%) than in pN0 tumors (49%; P = .089). Kaplan-Meier and log-rank tests revealed that moderate (2+) to strong (3+) NFATc1 expression correlated with lower progression-free survival (P = .032) and cancer-specific survival (P = .005) rates in the 99 cases. Patients with high (2+/3+) NFATc1 muscle-invasive tumor (n = 9) also had a significantly higher risk of cancer-specific mortality (P = .021) compared to those with low (0/1+) NFATc1 muscle-invasive tumor (n = 53). Thus, compared with nonneoplastic urothelium, a significant increase in the expression of NFATc1 in UUTUC was seen, implying the involvement of NFATc1 signals in the development of UUTUC. The current results further suggest that NFATc1 overexpression serves as a predictor of poor prognosis in patients with UUTUC.