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Dive into the research topics where Hiroki Shirakawa is active.

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Featured researches published by Hiroki Shirakawa.


Cancer | 1996

Immunohistochemical analysis of proliferating cell nuclear antigen, p53 protein and nm23 protein, and nuclear DNA content in transitional cell carcinoma of the bladder

Hiroaki Shiina; Mikio Igawa; Haruhiko Nagami; Hiroshi Yagi; Shinji Urakami; Tatsuaki Yoneda; Hiroki Shirakawa; Tomoyuki Ishibe; Masahiro Kawanishi

Transitional cell carcinoma (TCC) of the bladder displays an unpredictable biologic behavior and the morphologic methods of grading tumor malignancy are often insufficient to predict the clinical outcome of patients with TCC of the bladder. Thus, the new indicator should reliably reflect prognosis. In this study, the authors determined the prognostic significance of proliferating cell nuclear antigen (PCNA), p53 protein, and nm23 protein, as well as nuclear DNA content in specimens with TCC of the bladder.


Contributions To Nephrology | 2009

Evaluation of Two Different Preconditioning Regimens for ABO-Incompatible Living Kidney Donor Transplantation

Kazunari Tanabe; Hideki Ishida; Tomokazu Shimizu; Kazuya Omoto; Hiroki Shirakawa; Tadahiko Tokumoto

INTRODUCTIONnAlthough splenectomy has been employed in most documented protocols for ABO-incompatible kidney transplantation (ABO-ILKT), its utility is not yet determined. The aim of this study was to evaluate the long-term results of ABO-ILKT with splenectomy, and also compare the outcome of ABO-ILKT with splenectomy versus non-splenectomy.nnnMETHODSnWe did a retrospective study of ABO-incompatible living donor kidney transplants at our institution and affiliated hospital between January 2001 and December 2006 (n = 70). All patients were treated with a combination of immunosuppressive drugs, including tacrolimus (FK), mycophenolate mofetil (MMF) and methylprednisolone (MP). Between January 2001 and December 2004, all patients underwent pretransplant double filtration plasmapheresis (DFPP) and splenectomy at the time of transplant (n = 46) (ABO-I-SPX group). Between January 2005 and December 2006, splenectomy was not performed and a protocol that involved pretransplant low-dose injection of rituximab was employed (ABO-I-RIT group). ABO-compatible living kidney transplants (n = 55) performed between January 2001 and December 2004 were employed as a control group (ABO-C group).nnnRESULTSnPatient survival was 100% in all groups. Three-year graft survival was 98.2, 93.5 and 95.8% in the ABO-C, ABO-I-SPX and ABO-I-RIT groups, respectively. Five-year graft survival was 93 and 91.3% in the ABO-C and ABO-I-SPX groups, respectively. Renal allograft function was comparable among the three groups. However, compared to the ABO-I-RIT group, the incidence of acute antibody-mediated rejection (acute AMR) or chronic AMR was significantly higher in the ABO-C and ABO-I-SPX groups.nnnCONCLUSIONSnAlthough long-term outcome of the ABO-I-SPX group was excellent and showed no significant difference compared to the ABO-C group, splenectomy is not essential for successful ABO-ILKT. The rituximab-treated patients showed excellent short-term graft survival and renal function, and the incidence of AMR in the ABO-I-RIT group was significantly reduced compared to the ABO-I-SPX group.


Transplantation | 2010

Evaluation of Low-Dose Rituximab Induction Therapy in Living Related Kidney Transplantation

Toshio Takagi; Hideki Ishida; Hiroki Shirakawa; Tomokazu Shimizu; Kazunari Tanabe

Background. Rrituximab has been used for desensitization of anti-blood type antibody and anti-human leukocyte antigen (HLA) antibody as an induction immunosuppressant in our hospital. After having used rituximab for more than 2 years, we performed a retrospective study to clarify the effectiveness and safety of rituximab. Materials and Methods. We performed 144 kidney transplants between January 2005 and December 2007 at our hospital. Low-dose rituximab was administered to 78 of these transplant recipients as an induction immunosuppressant. A comparison of viral infection, leucopenia, and rejection incidence between patients administered (Rit group) and not administered (Non-Rit group) rituximab before kidney transplantation was performed. Result. A comparison of Rit group and Non-Rit group revealed no significant difference in the incidence of cytomegalovirus infections (Rit: 26%, Non-Rit: 29%; P=1.00), BK virus infections (Rit: 2.6%, Non-Rit: 0%; P=0.53), or leukopenia (Rit:23%, Non-Rit: 14%; P=0.25) between the two groups of patients. The incidence of acute antibody-mediated rejection was also not significantly different between the two groups (Rit: 6.8%, Non-Rit: 8.3%; P=0.75). On the other hand, the incidence of acute T-cell-mediated rejection was significantly lower in the Rit group (Rit: 8.2%, Non-Rit: 23.3%; P<0.05). Anti-HLA antibodies belonging to HLA class 1 and class 2 were depleted by 70% and 83%, respectively, for more than 2 years after rituximab administration. Conclusions. We could confirm the effectiveness and safety of rituximab more than 2-year follow-up period.


European Urology | 1997

Clinical significance of immunohistochemically detectable p53 protein in renal cell carcinoma

Hiroaki Shiina; Mikio Igawa; Shinji Urakami; Hiroki Shirakawa; Tomoyuki Ishibe; Masahiro Kawanishi

OBJECTIVEnTo elucidate the clinical significance of p53 protein in renal cell carcinoma (RCC).nnnMATERIALS AND METHODSnThe p53 protein in the paraffin-embedded materials taken from 72 patients with RCCs was evaluated immunohistochemically and was compared with the histological findings, expression of proliferating cell nuclear antigen (PCNA), genetic instability as assessed by 2c deviation index (2cDI) and 5c exceeding rate (5cER) as well as clinical outcome.nnnRESULTSnThe p53 positivity was demonstrated only in a localized and/or focal area of the cancerous tissue. The positive rate of p53 protein was 40.3% in this study. The p53 protein significantly correlated with nuclear grade as well as PCNA expression (p < 0.001 and p < 0.01, respectively). Although there was a wide scatter of 2cDI and 5cER values between p53 positive and negative RCCs, the RCC with positive p53 exhibited significantly higher values in 2cDI as well as 5cER, as compared to that with negative p53 (p < 0.02 and p < 0.005, respectively). However, some of the RCCs with negative p53 showed relatively higher values in 2cDI and 5cER. Using univariate analysis, the prognostic relevance was noted in T, N, M categories, age and p53 positivity, while it was not in 2cDI, 5cER and PCNA expression. Multivariate analysis demonstrated that N category and p53 positivity were independently significant indicators in predicting survival.nnnCONCLUSIONSnThe presence of p53 protein might reflect the genetic instability already occurred. The p53 positivity reflecting a high cellular proliferation could afford an additional but useful information when predicting survival in patients with RCC.


Journal of Endourology | 2010

Retroperitoneoscopic Living Donor Nephrectomy: Experience of 425 Cases at a Single Center

Naoki Kohei; Omoto Kazuya; Toshihito Hirai; Yuki Miyauchi; Shoichi Iida; Hiroki Shirakawa; Tomokazu Shimizu; Hideki Ishida; Kazunari Tanabe

BACKGROUND AND PURPOSEnLaparoscopic living donor nephrectomy (LLDN) is a standard method of donor nephrectomy. Most cases of LLDN are transperitoneal. Retroperitoneal access, however, implies a direct approach to the retroperitoneal organs without interfering with any of them. Since 2001, we have been trying to establish the technique of retroperitoneoscopic live donor nephrectomy (RPLDN). To assess the safety, feasibility, and usefulness of RPLDN, we reviewed the experience with this technique at our institution.nnnPATIENTS AND METHODSnFrom July 2001 to March 2009, 425 patients underwent live donor renal transplantation at our institution with allografts procured by RPLDN. Study variables included operative time, time to retrieval of the kidney, blood loss, warm ischemia time, length of hospital stay, number and length of renal vessels, graft function, and complications.nnnRESULTSnMean follow-up was 53 months. Donor nephrectomy was performed successfully in all patients. The complication rate was 4.9%. In one case, the procedure was changed to open donor nephrectomy because of severe adhesion in the renal hilum from previous surgery. Ureteral complications occurred in four patients, who were successfully treated with retrograde ureteral stent placement. None of the donors needed readmission. Mean warm ischemia time was 4.8 minutes. Creatinine levels returned to normal in all patients, and long-term allograft function was good. Serum creatinine levels at postoperative days 1, 7, and 14 were 3.7 mg/dL, 1.4 mg/dL, and 1.4 mg/dL on average, respectively. Slow graft function was noted in four (1.1%) cases but returned to the normal level within 2 weeks after surgery. One-year donor survival was 99%, and 1-year graft survival was 98.2%.nnnCONCLUSIONSnExcellent donor safety and allograft function were obtained with RPLDN. These results suggest that RPLDN could be an option for LLDN.


International Urology and Nephrology | 2010

New-onset diabetes after transplantation in tacrolimus-treated, living kidney transplantation: long-term impact and utility of the pre-transplant OGTT

Shoichi Iida; Hideki Ishida; Tadahiko Tokumoto; Kazuya Omoto; Hiroki Shirakawa; Tomokazu Shimizu; Hiroyuki Amano; Kiyoshi Setoguchi; Taiji Nozaki; Daisuke Toki; Daisuke Tokita; Kazunari Tanabe

BackgroundTo evaluate the role of the oral glucose tolerance test (OGTT) before transplantation and to examine the risk factors for new-onset diabetes after transplantation (NODAT) during long-term follow-up of renal transplant recipients receiving FK-based therapy.MethodsThe study evaluated 378 patients pre-transplantation using the OGTT and assigned them to one of three groups: Group 1, normal pattern; Group 2, impaired fasting glucose (IFG)/impaired glucose tolerance (IGT) pattern (IFG/IGT); and Group 3, DM pattern.ResultsAlthough the incidence of NODAT was higher in Group 3 than in groups 1 and 2, no significant difference was found between the three groups with regard to graft survival during long-term follow-up. Multivariate analysis showed that only a family history of diabetes was a significant factor determining NODAT progression.ConclusionsImpaired glucose tolerance appears to be a threshold influencing NODAT; however, it was not a significant factor in graft survival. Careful monitoring and management based on the result of the pre-transplantation OGTT appear to prevent the deterioration of impaired glucose tolerance in renal transplant recipients receiving FK-based therapy, even when a pre-operative OGTT shows impaired glycemic control.


Transplant International | 2009

Cytomegalovirus infection following renal transplantation in patients administered low‐dose rituximab induction therapy

Hayato Nishida; Hideki Ishida; Toshiaki Tanaka; Hiroyuki Amano; Kazuya Omoto; Hiroki Shirakawa; Tomokazu Shimizu; Shoichi Iida; Daisuke Toki; Yutaka Yamaguchi; Kazunari Tanabe

Anti‐CD20 antibody (rituximab) is recently being used as a B cell‐depleting agent in renal transplantation (RTx). However, the incidence of infectious complications associated with rituximab therapy remains uncertain. We evaluated the incidence of cytomegalovirus (CMV) infection associated with rituximab therapy in RTx. A total of 83 patients were enrolled. The immunosuppressive regimen consisted of tacrolimus or cyclosporin, mycophenolate mofetil, methylprednisolone and basiliximab. In 54 patients, only one dose of rituximab (200 or 500u2003mg/kg body weight) was given before RTx. A total of 25 of 43 (58.1%) recipients who were CMV seropositive prior to RTx and who received rituximab induction therapy developed CMV infection, compared to 18 of 24 (75%) CMV seropositive recipients who did not receive rituximab therapy (Pu2003=u20030.1676). A total of 8 of 11 patients who were CMV seronegative prior to RTx and who received rituximab developed CMV infection. However, CMV seroconversion was seen in all 8 of these infected patients. Low‐dose rituximab induction therapy in renal transplant recipients appears to have no influence on the incidence of CMV infection and CMV seroconversion. However, we have to consider anti‐CMV prophylaxis therapy, because of high incidents of CMV infection, especially for CMV seronegative recipients who received rituximab.


Transplant Immunology | 2010

Changes in anti-HLA antibody titers more than 1 year after desensitization therapy with rituximab in living-donor kidney transplantation

Toshio Takagi; Hideki Ishida; Hiroki Shirakawa; Tomokazu Shimizu; Kazunari Tanabe

One hundred sixty-five kidney transplantations were performed from January 2005 to December 2007 at our hospital. Low-dose rituximab was administered to 78 patients as an induction immunosuppressant. Of the 78, 48 were donor-specific anti-HLA antibodies (DSA)-positive, and the changes in the anti-HLA antibody titers could be followed up postoperatively in 35 of these patients. Anti-HLA antibodies belonging to HLA class 1 and HLA class 2 were depleted by 74% and 86%, respectively, and remained depleted for more than 2 years. Although there were no cases of graft loss, one patient suffered from chronic AMR. Thus, we could control DSA for at least a few years after kidney transplantation using rituximab as desensitization therapy.


International Journal of Urology | 2010

Bladder function of end‐stage renal disease patients

Kuniko Tsunoyama; Hideki Ishida; Kazuya Omoto; Tomokazu Shimizu; Hiroki Shirakawa; Kazunari Tanabe

Objectives:u2003 To evaluate the bladder function of end‐stage renal disease (ESRD) patients by using video H2O cystometry (CM) before renal transplantation (RTx).


Oncology | 1996

Immunohistochemistry of p53 Protein in Transitional-Cell Carcinoma of the Bladder Using an Image Analyzer

Hiroaki Shiina; Mikio lgawa; Hiroshi Yagi; Shinji Urakami; Tatsuaki Yoneda; Hiroki Shirakawa; Tomoyuki Ishibe

The p53 protein is known to be the product of the tumor suppressor gene p53. To elucidate the biological characteristics of p53 protein in transitional-cell carcinoma (TCC) of the bladder, the positive rate (PR) and positive intensity (PI) of p53 immunostaining in 72 TCCs of the bladder were quantified and compared with clinicopathological findings, prognosis and expression of proliferating-cell nuclear antigen (PCNA). The immunoreactivity for p53 and PCNA was evaluated using the CAS 200 Image Analyzer (Cell Analysis System, Elmhurst, Ill., USA). Intense immunoreactivity for p53 protein was observed not only near the basal cell layer but also at the invasive border. Both PR and PI of p53 were significantly correlated with histological grade (p < 0.05 and P < 0.02, respectively), histological stage (p < 0.02 and p < 0.02, respectively). Both PR and PI of p53 were significantly higher in patients who died of bladder cancer and in patients who developed metastatic progression. Using a univariate analysis, the survival was significantly short in subjects with high PR (> 40%) or high PI (> 70%) of p53 (p < 0.01 in both cases). However, using a multivariate analysis, the prognostic value of p53 immunoreactivity was not superior to histological stage. These findings suggested that, although p53 immunoreactivity appears to be related to proliferative activity in TCCs of the bladder, the prognostic relevance of p53 immunoreactivity was rather limited when evaluating the biological attitude of individual TCC of the bladder.

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Shinji Urakami

Japanese Foundation for Cancer Research

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