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Shiro Takahara

Publications and source records attributed to Shiro Takahara.

At least 37 records · Page 2Linked to original sources
PubMed2005

[A rare case of transitional cell carcinoma of the ileum segment arising 43 years after ureteroileocystoplasty due to tuberculous bladder atrophy].

A 60-year-old woman visited our hospital complaining of fever up. She had undergone augmentation ileoplasty for tuberculous bladder atrophy 43 years age. Cystoscopy revealed a broadbased tumor on the ileal segment. Histopathological findings of the biopsy specimen demonstrated grade 3 transitional cell carcinoma. She was given 2 courses of chemotherapy (methotrexate, vincristine, adriamicin, cisplatin), but died of metastasis of carcinoma 4 months after diagnosis.

Anastomosis, Surgical↗
PubMed2004

Mycophenolate mofetil prevents autoimmune glomerulonephritis and alterations of intrarenal adrenomedullin in rats.

We studied the effects of mycophenolate mofetil, a specific inhibitor of inosine monophosphate dehydrogenase, on the mercuric chloride induced autoimmune glomerulonephritis in Brown Norway rats and also on the renal contents of adrenomedullin. In the rats with autoimmune glomerulonephritis, plasma and renal tissue adrenomedullin levels were increased significantly. Coadministration of mycophenolate mofetil resulted in prevention of autoimmune glomerulonephritis and also in maintaining of plasma and renal tissue adrenomedullin levels at control levels. Adrenomedullin mRNA expressions in the renal cortex were also higher in the rats with autoimmune glomerulonephritis. Significant positive correlations were found between renal cortical adrenomedullin levels and urinary Na+ and N-acetyl-beta-D-glucosaminidase excretion. A significant negative correlation between renal cortical adrenomedullin levels and creatinine clearance was also found. These results suggest that mycophenolate mofetil suppresses the renal damage in rats with autoimmune glomerulonephritis and renal adrenomedullin may participate in the pathophysiology of autoimmune glomerulonephritis.

Adrenomedullin↗
PubMed2004

Susceptibility gene for non-obstructive azoospermia in the HLA class II region: correlations with Y chromosome microdeletion and spermatogenesis.

We previously reported an association between the human leukocyte antigen (HLA) haplotype DRB1*1302-DQB1*0604 in the HLA class II region and non-obstructive azoospermia in Japanese men. To identify possible associations between the HLA-DRB1*1302-DQB1*0604 allele in the HLA class II region and azoospermia factor (AZF) deletion in the Y chromosome, we performed genomic polymerase chain reaction (PCR) analysis of the AZF region. We then determined spermatogenic impairment (Johnsen score) in testicular biopsy specimens from patients with or without the DRB1*1302-DQB1*0604 haplotype. The AZF microdeletion rate in patients with this haplotype was 3.85%, compared with 11.8% in others (no correlation). However, Johnsen scores in patients with the DRB1*1302-DQB1*0604 haplotype were 3.13 +/- 1.34 (mean +/- SD), compared with 3.70 +/- 1.51 in others (p < 0.05). While the DRB1*1302-DQB1*0604 haplotype acts independently from Y chromosome deletion, the haplotype might either act directly, or be functionally related to an unknown autosomal gene. In either case, this haplotype showed association with severe spermatogenic impairment.

Chromosome Deletion↗
PubMed2004

Direct transfer of hepatocyte growth factor gene into kidney suppresses cyclosporin A nephrotoxicity in rats.

BACKGROUND: The clinical utility of cyclosporin A (CsA) has been limited by its nephrotoxicity, which is characterized by tubular atrophy, interstitial fibrosis and progressive renal impairment. Hepatocyte growth factor (HGF), which plays diverse roles in the regeneration of the kidney following acute renal failure, has been reported to protect against and salvage renal injury by acting as a renotropic and anti-fibrotic factor. Here, we investigated protective effects of HGF gene therapy on CsA-induced nephrotoxicity by using an electroporation-mediated gene transfer method. METHODS: CsA was orally administered as a daily dose of 30 mg/kg in male Sprague-Dawley rats receiving a low sodium diet (0.03% sodium). Plasmid vector encoding HGF (200 micro g) was transferred into the kidney by electroporation. RESULTS: HGF gene transfer resulted in significant increases in plasma HGF levels. Morphological assessment revealed that HGF gene transfer reduced CsA-induced initial tubular injury and inhibited interstitial infiltration of ED-1-positive macrophages. In addition, northern blot analysis demonstrated that cortical mRNA levels of TGF-beta and type I collagen were suppressed in the HGF group. Finally, HGF gene transfer significantly reduced striped interstitial phenotypic alterations and fibrosis in CsA-treated rats, as assessed by alpha-smooth muscle actin expression and Masson's trichrome staining. CONCLUSIONS: These results suggest that HGF may prevent CsA-induced tubulointerstitial fibrosis, indicating that HGF gene transfer may provide a potential strategy for preventing renal fibrosis.

Animals↗
PubMed2004

Comprehensive examination of gene expression associated with long-term stable graft acceptance by renal transplant recipients.

Expression levels of mRNA in peripheral blood mononuclear cells from five renal transplant recipients and five non-transplanted controls were analyzed with GeneChips (GeneChip Instrument system, Affymetrix, Santa Clara, CA, USA). All recipients had retained a well-functioning kidney graft for more than 15 yr on low-dose maintenance immunosuppression. Among a total of 12630 transcripts examined, significant differential expression was observed for 599 genes, whereby 470 genes were up-regulated and 129 down-regulated in the transplant recipients compared with controls. Of these, 192 up-regulated and 46 down-regulated genes showing a change greater than twofold were divided into eight functional categories as follows (numbers of genes, up/down): immune system (12/14), cell proliferation (17/3), oncology (15/3), transporter/receptor/binding protein (16/5), transcription factors (8/2), enzymes (17/4), expressed sequence tags (91/9), and others (16/6). Predictably, expression of immune-associated genes was decreased in the recipients. Significant reduction of expression levels of CD3, ICAM-1, and B7.2, which are critical molecules for interactions between antigen presenting cells and T cells, were observed. In T cell signal transduction, the Ras pathway was likely to be suppressed by activation of hVH-5. The present data help to elucidate the immunological status in long-term kidney graft recipients and may provide insights for future regimens to establish donor-specific hyporesponsiveness.

Adult↗
PubMed2004

Excellent long-term outcome of ABO-incompatible living donor kidney transplantation in Japan.

Owing to the severe shortage of cadaveric grafts in Japan, we have performed ABO-incompatible living donor kidney transplantation since 1989. This study assessed short- and long-term outcomes in 441 patients who received ABO-incompatible living donor kidney transplants between January 1989 and December 2001. We compared our results with historical data from 1055 recipients of living kidney transplantation. Overall patient survival rates 1, 3, 5, 7, and 9 years after ABO-incompatible transplantation were 93%, 89%, 87%, 85%, and 84%, respectively. Corresponding overall graft survival rates were 84%, 80%, 71%, 65%, and 59%. After ABO-incompatible transplantation, graft survival rates were significantly higher in patients 29 years or younger than in those 30 years or older and in patients who received anticoagulation therapy than in those who did not receive such therapy. There were no significant differences between A-incompatible and B-incompatible recipients with respect to clinical outcomes. The graft survival rate at 1 year in the historical controls was slightly but not significantly higher than that in our recipients of ABO-incompatible transplants. We conclude that long-term outcome in recipients of ABO-incompatible living kidneys is excellent. Transplantation of ABO-incompatible kidneys from living donors is a radical, but effective treatment for end-stage renal disease.

ABO Blood-Group System↗
PubMed2004

Relation between erectile dysfunction and urinary incontinence after nerve-sparing and non-nerve-sparing radical prostatectomy.

INTRODUCTION: We investigated the status of erectile function and urinary continence after radical prostatectomy to investigate a possible relation between them and then determined whether the status of postoperative urinary continence affected erectile function. PATIENTS AND METHODS: Seventy-six patients who had no symptoms of erectile dysfunction or urinary incontinence preoperatively were included in this study. The postoperative status of erectile function and urinary continence was investigated using a self-reported patient questionnaire. RESULTS: Thirteen of 27 patients (48.1%) who underwent nerve-sparing procedures maintained erectile function, while 7 of 49 patients (14.2%) who underwent non-nerve-sparing procedures maintained it postoperatively. None of the 27 patients in the nerve-sparing procedure group reported incontinence, whereas 3 of the 49 patients (6.1%) who underwent non-nerve-sparing procedures reported moderate incontinence. However, no significant correlation between the International Index of Erectile Function-5 score and the Incontinence Impact Questionnaire score was seen. CONCLUSION: No relation between the status of urinary continence and erectile function was shown, regardless of the nerve-sparing nature of the prostatectomy.

Aged↗
PubMed2003

Significant prolongation of animal survival by combined therapy of FR167653 and cyclosporine A in rat renal allografts.

BACKGROUND: Cyclosporine A (CsA) has improved short-term results in renal transplantation. However, its toxicities have been serious problems in clinical patients undergoing long-term administration. It is necessary to develop a nonnephrotoxic immunosuppressant that allows reducing doses of CsA. The authors tested the effect of a new pyrazolotriazin compound, FR167653 (FR), that inhibits the production of proinflammatory cytokines, using a rat renal acute-rejection model (Wistar-Lewis). METHODS: The authors first examined the adverse reactions of FR in naive rats. The effect of FR monotherapy was evaluated by treating allograft recipients at a dosage of 32 or 64 mg/kg/day intraperitoneally. The synergistic effect of FR and CsA at a minimum dose was examined by treating the recipients daily with 64 mg/kg of FR and 0.1, 0.5, or 1.0 mg/kg of CsA. RESULTS: Long-term administration of FR caused no severe adverse reactions in naive rats at less than 96 mg/kg/day, and FR is a nonnephrotoxic but liver-toxic agent at higher doses. Monotherapy of FR (8.7+/-1.3 days) or CsA (8.7+/-1.7 days) did not influence graft survival (vs. 8.2+/-0.8 in controls, n=10). However, the combined treatment of FR and CsA significantly prolonged animal survival (>50% of animals survived a 42-day follow-up period; P<0.01 vs. all other groups, n=15/group). Immunologic analysis demonstrated the significantly decreased production of major inflammatory mediators and adhesion molecules in the allografts as compared with those of all other groups. CONCLUSIONS: A nonnephrotoxic agent, FR may be a promising candidate for a new combined immunosuppressive regimen that potentially reduces the amount of CsA.

Animals↗
PubMed2003

Correlation between the Banff 97 classification of renal allograft biopsies and clinical outcome.

The 1997 fourth Banff meeting revised the consensus for describing transplant biopsies. We have conducted a retrospective analysis of biopsies correlated between the Banff 97 classification and clinical outcome. The patients ( n=149), who had a total of 404 biopsy-proven rejections, were assessed and the biopsies taken from these patients were re-examined and classified according to the Banff 97 classification. Morphological changes in the glomeruli (g), interstitium (i), tubules(t), and arterial vessels (v) were scored. Severity of acute rejection was statistically associated with unresponsiveness to anti-rejection treatment ( P<0.0001) and predicted an increased risk of graft failure ( P<0.05). Each quantitative criterion (g, i, t, and v) was also statistically associated with unresponsiveness to anti-rejection treatment. Mean serum creatinine levels were significantly higher in the groups graded Banff 97 type I-III after 1 and 2 years of follow-up. The Banff 97 classification correlated with reversibility of rejection episodes and long-term graft survival.

Biopsy↗
PubMed2003

Outcome of 3 years of immunosuppression with tacrolimus in more than 1,000 renal transplant recipients in japan.

BACKGROUND: In Japan, the new macrolide immunosuppressant, tacrolimus, was approved for the prevention and treatment of allograft rejection in renal transplant recipients in April 1996. This article summarizes efficacy and safety data for tacrolimus gathered since its approval. METHOD: Data from 1,007 patients who received tacrolimus-based treatment after kidney transplantation at 35 leading Japanese transplant centers between April 1996 and December 2000 were retrospectively analyzed. RESULTS: The renal transplants consisted of 856 living (756 ABO compatible, 100 ABO incompatible) and 151 cadaveric (146 non-heart-beating, 5 brain dead) donor grafts. Mean follow-up duration was 24.4 months. Overall patient and graft survival rates were 98.4% and 94.8% at 1 year, 98.0% and 92.6% at 2 years, and 97.6% and 90.4% at 3 years, respectively. Graft survival rates in living and non-heart-beating donor graft transplantations were 95.9% and 88.8% at 1 year, 94.0% and 85.0% at 2 years, and 92.2% and 80.0% at 3 years, respectively. Graft survival rates in living ABO-compatible donor graft transplantation ranged from 93.4% to 97.5%, and in ABO-incompatible cases, rates were stable at 83.2% throughout the 3-year assessment period. Median serum creatinine levels ranged from 1.30 to 1.37 mg/dL during this time. Percentages of patients receiving antihyperlipidemics, antihypertensives, and insulin were 12.6%, 41.1%, and 6.5% at 1 year, respectively, and remained low at 3 years after transplantation. CONCLUSION: Three years of tacrolimus therapy demonstrated excellent efficacy and safety in more than 1,000 renal transplant recipients, including recipients of living ABO-incompatible and non-heart-beating donor grafts, with favorable graft function maintained.

ABO Blood-Group System↗
PubMed2003

Gene transfer into the liver by plasmid injection into the portal vein combined with electroporation.

BACKGROUND: We investigated the optimum conditions for gene transfer into the liver by injection of plasmid via the portal vein combined with electroporation. METHODS: In anesthetized 7-week-old male Shionogi Wistar rats, a tapered 3Fr. catheter was inserted through a branch of the colonic vein and its tip was secured into the portal vein. After clamping the vessels around the right and caudal lobes of the liver, FITC-oligodeoxynucleotide (ODN), green fluorescence protein (GFP) plasmid, or pCAGGS-luciferase was injected into the right and caudal lobes during electroporation using electric pulses applied to the caudal lobe only. RESULTS: Transfected cells were identified by FITC-ODN and GFP fluorescence, and transfection efficacy was estimated by measurement of luciferase activity. FITC-ODN and GFP were detected in the caudal lobes of the liver. FITC-ODN was particularly present in hepatocytes surrounding the Glisson capsule and central veins, while GFP was detected in only hepatocytes surrounding the Glisson capsule. Luciferase activity in the liver was dependent on the plasmid concentration and voltage of the electric pulse, but independent of the volume of plasmid solution. Luciferase activity was limited in the right lobe, in which plasmid solution was injected but no electroporation was applied. CONCLUSIONS: Our results showed local expression of the induced gene at the electroporation site, suggesting it is potentially useful for liver function support during recovery after extensive liver surgery and for the treatment of chronic and/or diffuse liver diseases.

Animals↗
PubMed2003

Electroporation-mediated ex vivo gene transfer into graft not requiring injection pressure in orthotopic liver transplantation.

BACKGROUND: We investigated optimum conditions for ex vivo gene transfer into liver grafts by plasmid injection via the portal vein combined with electroporation in rat liver transplantation. METHODS: Anesthetized 9-week-old male Shionogi-Wistar rats were used as donors and recipients. After harvest of the liver graft from the donor rat, a tapered 3Fr. catheter was inserted into the portal vein of the liver graft ex vivo. After clamping the afferent vessels around the right and caudal liver lobes, pCAGGS-luciferase, which was diluted with one of several osmotic pressure solutions, or pCAGGS-green fluorescence protein (GFP) plasmid was injected into these lobes to keep the efferent vessels patent. Electrical pulses were applied to the liver graft during cold preservation in lactated Ringer's solution, University of Wisconsin solution, and histidine-tryptophan-ketoglutarate solution. RESULTS: Transfection efficacy was estimated by measurement of luciferase activity. Luciferase activity in the liver was dependent on both the voltage and electric current of the electrical pulse, and also on the type of preservation solution and plasmid osmotic pressure. Luciferase activity was noted only in plasmid-injected lobes of the liver graft. GFP-transfected cells were identified by GFP fluorescence. GFP was observed predominantly in perivascular cells, including hepatocytes. CONCLUSIONS: We have demonstrated successful ex vivo gene transfection into liver grafts without injection pressure by using a non-viral method.

Animals↗
PubMed2003

Experience with laparoscopic splenectomy for ABO-incompatible living related renal transplantation.

PURPOSE: To determine whether laparoscopic splenectomy for ABO-incompatible living related renal transplantation is safe and effective. PATIENTS AND METHODS: From July 2000 to May 2002, laparoscopic splenectomy was performed on the day of transplantation in 10 patients undergoing ABO-incompatible living related renal transplantation. Perioperative and postoperative data, including operative time, blood loss, and complications, were evaluated. RESULTS: The mean operative time was 79 minutes. Intraoperative blood loss ranged from 25 mL to 600 mL (mean 130 mL). Transfusion was not required in any case. One patient required open conversion because of bleeding from the splenic hilum. The serum amylase value was slightly elevated postoperatively in four patients but normalized with conservative treatment. One patient had bleeding from a trocar port wound, which was likewise treated conservatively. No complications, including postoperative renal dysfunction or fatal infections, that were considered attributable to the laparoscopic procedure were noted. CONCLUSIONS: Laparoscopic splenectomy performed simultaneously with renal transplantation is a safe and efficacious procedure for ABO-incompatible living related renal transplantation.

ABO Blood-Group System↗
PubMed2003

[A case report of BK virus nephropathy after an ABO-incompatible living kidney transplantation].

We present a case of 29-year-old female who underwent an ABO-incompatible living kidney transplantation from her father. The serum creatinine (s-Cr) level of this patient was stabilized about 1.1-1.2 mg/dl during the first 3 months after the transplantation. Thereafter, the function of allograft was deteriorated gradually. A biopsy performed on post-transplant day (PTD) 520 to evaluate a rise in creatinine revealed an interstitial nephritis and chronic renal allograft nephropathy. The renal function worsened persistently, although we increased the dosage of immunosuppressant subsequently. The following biopsy performed on PTD 630 showed a suspicion of BK virus nephropathy, with a mass of tubular epithelial nuclear inclusions and an interstitial nephritis. The diagnosis of BK virus nephropathy was confirmed on the immunohistochemistry staining using anti-SV40 antibody and PCR analysis. Despite reducing the immunosuppressants, the function of the allograft worsened progressively and was lost on PTD 912.

ABO Blood-Group System↗
PubMed2002

A novel immunosuppressive drug, FTY720, prevents the cancer progression induced by cyclosporine.

Cyclosporine A (CsA), the most frequently used immunosuppressive drug, has been reported to induce cancer by a cell-autonomous mechanism. Herein, we report that FTY720, a novel immunosuppressant, prevents CsA-induced alterations in both morphology and cell motility at a low concentration (0.1 microM) and induces the CsA-treated cancer cells to undergo apoptosis at a higher concentration (more than 5 microM). The inhibitory activity of FTY720 is unrelated to the decrease of TGF-beta. We believe that a combination treatment with FTY720 and CsA not only results in a synergistic effect on allografts, but also, reduces the incidence of cancer in transplant patients.

Apoptosis↗
PubMed2002

Anticarcinogenic effect of FTY720 in human prostate carcinoma DU145 cells: modulation of mitogenic signaling, FAK, cell-cycle entry and apoptosis.

Despite the high frequency of prostate cancer, therapeutic options for advanced disease are limited to chemotherapy, radiation or hormonal therapy and eventually fail in all patients. Therefore, alternative approaches need to be developed. We previously reported that FTY720, a metabolite from Isaria sinclarii, is a unique antitumor agent for an androgen-independent prostate cancer cell line and requires caspase-3 activation in apoptosis. In our study, we have evaluated the effect of FTY720 on a family of mitogen-activated protein kinases (MAPKs), focal adhesion kinase (FAK), mitochondrial transmembrane potential, caspase-9 and caspase-8 and analyzed the expression of some cell-cycle regulator proteins in DU145 cells in order to understand the various antitumor effects of FTY720. Apoptosis was quantified by phosphatidylserine exposure. Activation of MAPKs, cleavage of caspase-9 and caspase-8, status of cyclin-dependent kinases (CDKs) and Cip1/p21, a cyclin-dependent kinase inhibitor, were evaluated by Western blot analysis, in addition to FAK and phospho-FAK immunoprecipitation and cell-cycle analysis by FACScan. We found that in DU145 cells, 40 microM FTY720 caused activation of p38 MAPK and the upstream kinase MKK3/MKK6 but not SAPK/JNK. Mitochondrial transmembrane potential, FAK and ERK1/2 were reduced while caspase-9 and caspase-8 were cleaved. The p38-specific inhibitor had no effect on apoptosis induced by FTY720, whereas z-VAD.FMK, a broad-spectrum caspase inhibitor, did not inhibit the p38 MAPK activation. An amount of 20 microM FTY720 resulted in G(1) arrest and a decrease of CDK2 as well as CDK4, whereas it induced Cip1/p21. FTY720 may exert anticarcinogenic effects against prostate cancer cells possibly involving modulation of mitogenic signaling, cell-cycle regulators, induction of G(1) arrest and apoptotic death in DU145 cells.

Adenocarcinoma↗
PubMed2002

Marked prevention of tumor growth and metastasis by a novel immunosuppressive agent, FTY720, in mouse breast cancer models.

FTY720 is a unique immunosuppressive agent that exerts its activity by inducing apoptosis in lymphocytes. We conducted the present study to investigate the effects of FTY720 on cancer growth and metastasis, as well as its mechanism of action. In vitro treatment with FTY720 induced dramatic cancer cell apoptosis in a mouse breast cancer cell line, JygMC(A). Electron microscopy revealed distinct changes on the cell surface with decreased filopodias and microvilli in cancer cells treated with FTY720 at 2 microM and clear evidence of apoptosis at 10 microM. Interestingly, the effect of FTY720 was significantly less in the normal fibroblasts than in the cancer cells, indicating greater susceptibility of cancer cells to the agent. We then tested the in vivo effect of FTY720 in a mouse breast cancer model created by inoculating JygMC(A) cells (s.c.) in the flank region of BALB/c-nu/nu mice at three different dosages (2, 5, and 10 mg/kg/day; n = 30/group). Tumor growth was markedly suppressed at a dosage of 5 mg/kg or more without notable side effects. In addition, tumor metastasis, which was dramatically evident in control mice, was significantly prevented even at a low dose (2 mg/kg/day), resulting in a significant prolongation of animal survival. These data led us to additionally investigate the mechanism of action, especially the prevention of metastasis at a low dose. FTY720 treatment at 2 microM caused a remarkable cytoskeletal change with deformed and decreased filopodias in cancer cells. In addition, it significantly decreased the ability of cancer cells to adhere and migrate to extracellular matrix components, and markedly reduced the expression of integrins on the cancer cell surface. These results indicate that FTY720 is a potent anticancer agent that induces cancer cell apoptosis and is markedly effective for prevention of metastasis. The changes of cellular structure with reduction of integrin expression may be one of its underlying mechanisms of action.

Actins↗