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Shigeru Satoh

Publications and source records attributed to Shigeru Satoh.

At least 19 recordsLinked to original sources

Determination of rabeprazole enantiomers and their metabolites by high-performance liquid chromatography with solid-phase extraction.

Here, we describe the development of a rapid, simple and sensitive high-performance liquid chromatography (HPLC) method for the simultaneous quantitative determination of rabeprazole enantiomers (1a,b) and their metabolites, rabeprazole-thioether (2) and rabeprazole sulfone (3), in human plasma. Analytes and the internal standard (omeprazole-thioether) were separated using a mobile phase of 0.5 M NaClO4-acetonitrile (6:4, v/v) over a Chiral CD-Ph column. Analysis required only 100 microl of plasma and involved solid-phase extraction with an Oasis HLB cartridge, which gave high recovery (>91.8%) with good selectivity for all analytes. The lower limit of quantification was 5 ng/ml for analytes 1a, 1b and 3 and 10 ng/ml for 2. Linearity of this assay was determined to lie between 5 and 1000 ng/ml for 1a, 1b and 3 and 10 and 1000 ng/ml for 2 (r2>0.982 of the regression line). Inter- and intra-day coefficients of variation were less than 7.8% and accuracies were within 8.4% over the linear range for all analytes. Our results indicate that this method is applicable to the simultaneous monitoring of plasma levels of rabeprazole enantiomers and associated metabolites in human plasma.

2-Pyridinylmethylsulfinylbenzimidazoles↗

Outcome of right hand-assisted retroperitoneoscopic living donor nephrectomy.

OBJECTIVES: To compare the results of right and left hand-assisted retroperitoneoscopic living donor nephrectomy (HARDN) and assess the usefulness and feasibility of right HARDN. METHODS: A total of 68 HARDNs performed from July 2001 to February 2005 in Akita University Medical Center were entered into this study. Of these, 12 cases were right-sided HARDN. The reasons for selecting right HARDN were wandering right kidney in 4, multiple left renal arteries in 3, lower glomerular function presenting in the right kidney in 2 patients, and left renal stone, right renal cyst, and right renal aneurysm in 1 patient each. We compared the perioperative and postoperative results of the 12 right-sided HARDNs with those of the 56 left HARDNs. RESULTS: No significant differences were found between the two groups in the demographic data (ie, age, sex, number of renal arteries), except for the body mass index. None of the right HARDNs resulted in major complications or open conversion, but two left HARDNs required conversion to open surgery. No difference was found between the two groups regarding estimated blood loss, warm ischemia time, or time to oral intake, although the right HARDN group had a longer mean operative time. No significant differences were found in the recipient's postoperative graft function or in the frequency of delayed graft function. CONCLUSIONS: Right HARDN provided almost similar perioperative and postoperative outcomes compared with those of left HARDN. Our results indicate that right HARDN is a choice for living donor nephrectomy because of its technical feasibility, safety, and minimal invasiveness, which are comparable to those of left HARDN.

Adult↗

Hand assisted retroperitoneoscopic living donor nephrectomy in elderly donors.

PURPOSE: We assessed the influence of HARDN on residual donor kidney and allograft function, invasiveness and morbidity in elderly living donors. MATERIALS AND METHODS: A total of 89 living donors underwent nephrectomy before September 2004 at our institution. The 18 donors who were 65 years or older included 4 of 27 with ODN and 14 of 62 with HARDN. RESULTS: In older (65 years or older) donors mean operative time, mean blood loss and warm ischemia time in the HARDN group did not differ from those in the ODN group. None of the donors had major complications. Older donors with HARDN had a tendency toward a shorter hospital stay than those with ODN. Postoperative serum creatinine in older donors with HARDN was higher than that in younger donors with HARDN, while there was no difference in postoperative serum creatinine between older donors with HARDN and those with ODN. The frequency of allograft losses tended to be higher in older than in younger kidneys (4 of 18 vs 5 of 71, p = 0.054). However, most allograft losses did not seem to be related to surgical technique. CONCLUSIONS: Although further studies, especially with long-term followup, are necessary, HARDN is suggested to be safe and minimally invasive surgery even in elderly donors and to be comparable to open surgery in terms of morbidity, the residual donor kidney and allograft function.

Adult↗

Association of XRCC1 gene polymorphisms with the susceptibility and chromosomal aberration of testicular germ cell tumors.

It is known that many genomic and genetic alterations caused by aging or environmental factors are responsible for cancer development and progression. XRCC1 is involved in the repair of DNA single-strand breaks formed by exposure to ionizing radiation and alkylating agents. The objective of this study was to investigate the association of genomic alterations and the susceptibility of testicular germ cell tumors with XRCC1 polymorphisms. Two polymorphisms of XRCC1, Arg194Trp and Arg399Gln, were genotyped in 83 patients with testicular germ cell tumors (TGCT) and 87 male controls. Allelic imbalances (AI) were evaluated using 4 microsatellite markers in a subgroup of 50 patients. Patients with at least one Gln allele of the Arg399Gln polymorphism had an increased risk of TGCT than those with the Arg/Arg genotype (aOR=1.775, 95% CI=1.045-3.016, P=0.034). Furthermore, the increased risk associated with the Gln allele against the Arg homozygote was more strongly observed in patients with pure seminoma (aOR=2.242, 95% CI=1.149-4.374, P=0.018) or with metastasis (aOR=2.481, 95% CI=1.267-4.862, P=0.008). In the Arg194Trp polymorphism, there was no significant difference in the genotype distribution between TGCT patients and the controls. In AI analysis, the frequency of AI was significantly higher in tumors with at least one Gln allele than those with the Arg/Arg genotype in D13S317 (P=0.010) and in a combination of 4 markers (0.51+/-0.32 vs 0.32+/-28, P=0.028). Our results suggest that the Gln allele of the XRCC1 Arg399Gln polymorphism may genetically modify the development and progression of TGCT through genomic instability.

Chromosome Aberrations↗

[The research of the pathogen responsible for Pleurocybella porrigens related encephalopathy: investigation of 3-nitropropionic acid hypothesis].

Pleurocybella porrigens related encephalopathy exhibits consciousness disturbance and convulsion in the patients after taking and patients show bilateral basal ganglia lesion resulted in high mortality rate. This encephalopathy is a very similar to the moldy sugarcane encephalopathy epidemic in China in the past. We investigated the relationship between Pleurocybella porrigens related encephalopathy and 3-nitropropionic acid which had caused the moldy sugarcane encephalopathy. We have tried to detect 3-NPA in the various specimens from patients and Pleurocybella porrigens, but failed. Further examinations for elucidating the causation of Pleurocybella porrigens related encephalopathy are needed.

Aged↗

Stereoselective metabolism of rabeprazole-thioether to rabeprazole by human liver microsomes.

OBJECTIVE: Rabeprazole is metabolized mainly non-enzymatically to rabeprazole-thioether. This in vitro study was designed to clarify the stereoselective oxidation mechanism and to identify the enzyme(s) involved in the metabolic breakdown of rabeprazole-thioether to rabeprazole. METHODS: Rabeprazole-thioether was incubated with human liver microsomes and several recombinant cytochrome P450 (CYP) enzymes (CYPs 1A2, 2A6, 2B6, 2C9, 2C19, 2D6, 2E1, and 3A4). High-performance liquid chromatography was used for identification and quantification of each rabeprazole enantiomer. RESULTS: The K(m ) and V(max ) values for the formation of (R)-rabeprazole from rabeprazole-thioether in human liver microsomes were 6.6 microM and 92 pmol/min/mg protein, respectively, whereas those for the formation of (S)-rabeprazole were 5.1 microM and 21 pmol/min/mg protein, respectively. CYP3A4 was found to be the major enzyme responsible for(R)- and (S)-rabeprazole formation from rabeprazole-thioether. The intrinsic clearance (V(max ) /K(m )) for the oxidation by CYP3A4 of (R)-rabeprazole was 3.5-fold higher than that for the (S)-enantiomer (81 nl/min/pmol of P450 vs. 23 nl/min/pmol of P450). On the other hand, CYP2C19 and CYP2D6 were the main enzymes catalyzing the formation of desmethylrabeprazole-thioether from rabeprazole-thioether. The mean K(m ) and V(max ) values of desmethylrabeprazole-thioether formation for CYP2C19 were 5.1 microM and 600 pmol/min/nmol of P450, respectively, whereas those for CYP2D6 were 15.1 microM and 736 pmol/min/nmol of P450, respectively. DISCUSSION: Rabeprazole is reduced mainly non-enzymatically to rabeprazole-thioether, which is further stereoselectively re-oxidized by CYP3A4 mainly to (R)-rabeprazole. The difference in the enantioselective disposition of rabeprazole is determined by stereoselectivity in CYP3A4-mediated metabolic conversion from rabeprazole-thioether to rabeprazole.

2-Pyridinylmethylsulfinylbenzimidazoles↗

Clinical and genetic risk factors for posttransplant diabetes mellitus in adult renal transplant recipients treated with tacrolimus.

BACKGROUND: The present study investigated the incidence of posttransplant diabetes mellitus (PTDM) and calculated the risk of developing PTDM under a tacrolimus-based immunosuppression based on clinical characteristics, tacrolimus pharmacokinetics, and genetic polymorphisms related to tacrolimus pharmacokinetics or diabetes mellitus. METHODS: Seventy nondiabetic adult kidney recipients were studied. Patients with continuous high plasma glucose levels, over 6.5 mg/dl of hemoglobin A1c, or requiring insulin and/or oral antidiabetic agents for more than 3 months after transplantation 6 months postoperatively were diagnosed as having PTDM. Twelve genomic polymorphisms were assessed. RESULTS: Six months after transplantation, 10 recipients (14.3%) developed PTDM. Positive risk factors were age (P=0.019) and body mass index (P=0.038). There were no significant differences in acute rejection rate, total steroid doses, tacrolimus pharmacokinetics or its related to genetic polymorphisms between the two groups. The frequency of PTDM was significantly higher in patients with the vitamin D receptor (VDR) TaqI t allele than in those with the TT genotype (P=0.013). On multivariate analysis, age over 50 years (odds ratio 9.28, P=0.003) and the presence of the VDR TaqI t allele (odds ratio 7.05, P=0.048) were correlated with the development of PTDM. CONCLUSION: The incidence of PTDM was 14.3% in our cohort. Age over 50 years was a risk factor. The presence of the VDR TaqI t allele may also be a risk factor for PTDM, suggesting that genotyping of diabetes-related polymorphisms is a possible method of predicting a patient's risk for developing PTDM and would be a valuable asset in selecting appropriate immunosuppressive regimens for individuals.

Adiponectin↗

Expression of alpha-expansin and xyloglucan endotransglucosylase/hydrolase genes associated with shoot elongation enhanced by anoxia, ethylene and carbon dioxide in arrowhead (Sagittaria pygmaea Miq.) tubers.

BACKGROUND AND AIMS: Shoot elongation of arrowhead tubers (Sagittaria pygmaea Miq.) is stimulated by anoxia, ethylene and CO2. The aim of this study was to characterize anoxic elongation by comparison with elongation stimulated by ethylene and CO2. METHODS: The effects of the inhibitors aminoethoxyvinylglycine (AVG) as an ethylene biosynthesis inhibitor, 1-methylcyclopropene (1-MCP) as a potent inhibitor of ethylene action, and pyrazol, an inhibitor of alcohol dehydrogenase, on shoot elongation were examined. Moreover, the effects of these gaseous factors on expression of genes possibly involved in modification of cell wall architecture were examined by polymerase chain reaction (PCR) methods. KEY RESULTS AND CONCLUSIONS: In air, promotion by 5% CO2 and 5 microL L-1 ethylene of shoot elongation occurred. At 1% O2, ethylene also stimulated shoot elongation but CO2 did not. Pyrazol inhibited shoot elongation in hypoxia but not in normoxia, suggesting that alcohol fermentation contributes to elongation enhanced by hypoxia. AVG and 1-MCP partially prevented shoot elongation both in normoxia and in hypoxia, but they did not have significant effects in anoxia, suggesting that endogenous ethylene acts as a stimulator of shoot elongation in normoxia and in hypoxia but not in anoxia. Ethylene is not involved in anoxia-enhanced elongation. We cloned four cDNAs (SpEXPA1, 2, 3 and 4) encoding alpha-expansin (EXPA) and five cDNAs (SpXTH1, 2, 3, 4 and 5) encoding xyloglucan endotransglucosylase/hydrolase (XTH) from shoots of arrowhead tubers. The transcript levels of SpEXPA1 and 2 were increased by anoxia and those of SpEXPA2 were increased by 5% CO2. Ethylene slightly elevated the level of SpEXPA4 transcripts. Anoxia enhanced the transcript levels of SpXTH1 and 4; neither ethylene nor CO2 had any effect. CO2 enhanced transcript levels of SpXTH3 and depressed those of SpXTH5. Ethylene decreased transcript levels of SpXTH5. These results suggest that four SpEXPA genes and five SpXTH genes are differently responsive to anoxia, CO2 and ethylene. Enhancement of SpEXPA1 and 2, and SpXTH1 and 4 transcript levels suggests that these gene products are involved in anoxic shoot elongation through modification of cell wall architecture.

Amino Acid Sequence↗

Expression of sucrose synthase genes involved in enhanced elongation of pondweed (Potamogeton distinctus) turions under anoxia.

BACKGROUND AND AIMS: Overwintering buds (turions) of the monocot aquatic pondweed species (Potamogeton distinctus) are highly tolerant to anoxic stress. Sucrose metabolism accompanied by enhanced activity of sucrose synthase (SuSy) operates actively during anaerobic elongation of pondweed turions. The aim of this study is to isolate SuSy genes from the turions and to investigate their transcriptional changes in response to anoxia and other stimuli. METHODS: SuSy genes were isolated from pondweed turions by PCR methods and transcript levels of SuSy genes were examined in response to anoxia, sugars and plant hormones. In addition, the effects of anoxia on SuSy activity were examined both in the soluble fraction and in the microsomal fraction. KEY RESULTS: cDNAs of two SuSy genes (PdSUS1 and PdSUS2) were cloned from pondweed turions. The levels of PdSUS1 transcripts increased under anoxia but did not with sugar treatments. Anoxia-stimulated elongation of turions was further enhanced by 2,4-dichlorophenoxyacetic acid (2,4-D) and suppressed by treatments with sorbitol, 2-deoxyglucose (2-dGlc) and abscisic acid (ABA). The levels of PdSUS1 transcripts were increased by 2,4-D and decreased by sorbitol under anoxia. The levels of PdSUS2 transcripts were not significantly affected by anoxia and any other treatments. SuSy activity of turions under anoxia was enhanced in the soluble fraction, but not in the microsomal fraction. CONCLUSIONS: Up-regulation of PdSUS1 transcription under anoxia may not be attributed to sugar starvation under anoxia. A positive correlation between stem elongation and the level of PdSUS1 transcripts was observed in turions treated with anoxic conditions, 2,4-D and sorbitol. The increase in SuSy activity in the cytosol may contribute to sugar metabolism and sustain stem elongation under anoxia.

Amino Acid Sequence↗

Renal cell and transitional cell carcinoma in a Japanese population undergoing maintenance dialysis.

PURPOSE: We verified differences in the incidence, clinical characteristics and outcomes between patients on chronic dialysis for end stage renal disease with renal cell carcinoma (RCC) and those with transitional cell carcinoma (TCC). MATERIALS AND METHODS: Data regarding RCC and TCC were reviewed in the medical records of 6,201 patients with end stage renal disease who underwent chronic dialysis between January 1990 and June 2003 in our 38 affiliated dialysis centers, and data were compared with those reported in Australia and New Zealand. RESULTS: Among the patients RCC developed in 38 (0.61%) and TCC developed in 16 (0.26%) during maintenance dialysis. The primary renal disease was chronic glomerulonephritis in patients with RCC (68.4%) and diabetic nephropathy in patients with TCC (43.8%, p = 0.002). Mean patient age at initiation of dialysis was 45 years for those with RCC and 63 for those with TCC (p < 0.001). Mean interval from dialysis induction to tumor diagnosis was 143 months for patients with RCC and 54 months for patients with TCC (p < 0.001). Of 38 RCCs 23 (60.5%) were incidentally detected by regular abdominal imaging examinations while painless gross hematuria was the cardinal symptom in 13 (81.2%) of 16 TCCs. Overall and cancer specific survivals after tumor diagnosis were significantly superior in patients with RCC compared to those with TCC (p = 0.0001 and p = 0.0003, respectively), and the cancer specific 5-year survival was 88.9% for RCC and 29.5% for TCC. In both cancers tumor stage significantly increased the risk of cancer specific death. Compared with patients from Australia and New Zealand, the incidence of RCC was higher and that of TCC was lower in our patients (p <0.001). CONCLUSIONS: In the Japanese population on dialysis RCC is more common than TCC. Since long-term dialysis is a risk factor for RCC, regular imaging examinations may have contributed to the favorable outcome of our patients on dialysis with RCC. In contrast, the unfavorable outcome of TCC suggests the need for effective diagnostic measures for early detection of TCC in patients on dialysis.

Adolescent↗

Successful renal transplantation in the right iliac fossa 2 years after serious deep venous thrombosis in a patient with systemic lupus erythematosus.

Deep venous thrombosis (DVT) possibly occurs in the perioperative period, and induces serious complications such as a pulmonary embolism. On the other hand, allograft renal vein thrombosis leads to a high incidence of graft loss. We experienced a case in which a serious DVT occurred prior to renal transplantation; however, a successful renal transplantation in the right iliac fossa was performed after 2 years of anticoagulant therapy. It is suggested that the external iliac vein even after suffering from DVT can be anastomosed to an allograft vein successfully, when enough blood fl ow or a lower venous pressure is confirmed. However, one should be aware of the risk factors and the adequate management of thrombosis in renal transplantation because of the serious complications of DVT and the poor prognosis of allograft vein thrombosis.

Adult↗

Effects of a phenolic compound, resveratrol, on the renal function and costimulatory adhesion molecule CD86 expression in rat kidneys with ischemia/reperfusion injury.

Recent studies have suggested that an ischemia/reperfusion (I/R) injury enhances the expression of costimulatory adhesion molecules on the vascular endothelium. In the present study, we investigated the protective effects of resveratrol, a phenolic product, on the renal function and expression of CD86 in rat kidneys with I/R injury. Wistar rats were divided into four groups; 1) an I/R group with right nephrectomy and 1-hour clamping of the left renal pedicle; 2) a vehicle group, I/R plus 10% ethanol (0.1 ml/kg/day) administered by intra-peritoneal injection from day -1 through to 7; 3) a resveratrol group, I/R plus 4 mg/kg/day of resveratrol; and 4) a sham group. Blood samples were obtained via the tail vein at 1 day before, and 1, 3, and 7 days after the operation (day 0) for the measurement of serum creatinine (Scr) levels. The expression of CD86 protein was analyzed by immunofluorescence staining, and the level of CD86 messenger RNA (mRNA) was evaluated quantitatively by a real-time reverse transcription-polymerase chain reaction (RT-PCR) in the renal cortex at day 3. Scr levels of the resveratrol group were significantly lower than those of the I/R and vehicle groups on days 1 and 3 after the operation. From the immunohistochemical study, the expression of CD86 in the glomerular endothelium and peritubular vessels was found to be attenuated in the resveratrol group compared with the I/R or vehicle group. In the resveratrol group, the CD86 mRNA level was significantly lower than that in the I/R or vehicle group, and it was significantly decreased by about one fifth of that in the sham group. Our results suggest that resveratrol markedly reduces renal dysfunction and attenuates the mRNA and protein expression of CD86 following I/R injury.

Animals↗

[Two cases of urothelial cancer responsive to high-dose-intensity methotrexate vinblastine doxorubicin and cisplatin (M-VAC) therapy].

We report two cases of metastatic urothelial cancer treated with high-dose-intensity (HD) methotrexate vinblastine, doxorubicin and cisplatin (MVAC). After HD-MVAC, the size of primary and lymph node tumors decreased by 57-67% as compared with the standard M-VAC therapy. By shortening the dose interval, HD-MVAC may increase the anti-tumor effect without increasing side effects.

Aged↗

[Active combination immunochemotherapy with interferon-alpha, interleukin-2 and gemcitabine for four patients with metastatic renal cell carcinoma].

Immunochemotherapy consisting of interferon-alpha (IFN-alpha), interleukin-2 (IL-2), and gemcitabine (GEM) for metastatic renal cell carcinoma. A partial response maintained for 15 months, was obtained in one case resistant to IFN-alpha and IL-2 of para-aortic lymph node metastases (case 1). A minor response with 30% reduction of lung metastasis was obtained in one IFN-alpha resistant case, and the duration was 6 months (case 2). In one case, in contra-lateral renal metastasis, no disease progression was obtained for 6 months (case 3). One case with resistance to IFN-alpha and IL-2, and who had preoperative abnormalities of corrected serum calcium, serum c-reactive protein and hemoglobin, had progressive disease and died of cancer after 6 months (case 4). Grade 3 toxicity was noted in leucopenia (4/4), anemia (1/4), and nausea/ vomiting (1/4). Although the response duration was short, the combination immunochemotherapy consisting of IFN-alpha, IL-2 and GEM may be a promising salvage regimen for the patients with metastatic renal cell carcinoma.

Adult↗

[A case of fibroepithelial polyp of the ureter resected ureteroscopically].

A case of a giant fibroepithelial polyp of the ureter is presented. A 76-year-old woman was pointed out to have a tumorus lesion in the urinary bladder by ultrasonography. Intravenous pyelography showed a filling defect in the lower portion of the left ureter and bladder. Cystoscopy revealed a tumor with a smooth surface sticking out of the left ureteral orifice. After demonstration of benign ureteral polyp without malignancy by biopsy, ureteroscopic resection was performed. The stalk of the polyp was coagulated and removed with biopsy forceps under ureteroscopy. Pathological diagnosis was a fibroepithelial polyp. There were no findings of polyp recurrence or ureteral stenosis at 9 months after the operation. The diagnosis and management of fibroepithelial polyp are discussed.

Aged↗

[A case of giant epidermoid cyst occupying the testis].

A case of a giant epidermoid cyst of the testis is presented. A 65-year-old man was incidentally pointed out to have left scrotal painless swelling. Physical examination revealed an over hen-egg sized enlargement of the left scrotal contents. Ultrasonography revealed a 7.5 X 5.5 X 4.0 cm solid tumor with heterogeneous echogenicity. No other abnormal findings were observed including tumor markers. Since preoperative examination did not rule out malignancy, we performed left high orchiectomy. Pathological diagnosis was a epidermoid cyst of the testis with a small portion of atrophic testis. Although the preoperative diagnosis of testicular epidermoid cyst is possible, it may be considerably difficult when a giant epidermoid cyst is occupying the testis.

Aged↗

Association of lipoprotein lipase gene polymorphism with risk of prostate cancer in a Japanese population.

A high fat intake has been associated with prostate cancer risk, and gene polymorphisms of lipoprotein lipase (LPL) play an important role in plasma lipoprotein metabolism. We herein analyzed the association of LPL gene polymorphisms with the risk of prostate cancer in a Japanese population. Three single nucleotide polymorphisms (SNPs) of LPL designated as Ser447stop, HindIII and PvuII were genotyped by the polymerase chain reaction-restriction fragment length polymorphism method in 273 prostate cancer patients, 205 benign prostatic hyperplasia (BPH) patients and 230 male controls. The men with the CG + GG genotypes of the Ser447stop polymorphism had an increased risk of prostate cancer compared to those with the CC genotype [age-adjusted odds ratio (aOR) = 1.625; 95% CI = 1.068-2.471; p = 0.023]. Furthermore, the increased risk associated with the CG + GG genotypes was more strongly observed in patients with high-grade cancers (aOR = 2.843; 95% CI = 1.252-6.458; p = 0.039) or metastatic diseases (aOR = 2.300; 95% CI = 1.042-5.074; p = 0.013), whereas the risk was not significant in those with low- to intermediate-grade cancers or nonmetastatic diseases. In the HindIII and PvuII polymorphisms, there was no significant difference between the prostate cancer patients and the controls, and no significant results as for tumor grade and stage. None of the 3 polymorphisms showed any association with the risk of BPH. Our results suggest that the LPL Ser447stop polymorphism is a common genetic modifier for the development of prostate cancer, particularly that of high-grade and/or high-stage, in a Japanese population.

Aged↗