Akihiko Aoki

Urinary tract infections following renal transplantation.

The incidence of urinary tract infections (UTIs) in 363 adult renal transplant recipients transplanted during the period 1990-96 has been analysed. UTI occurred in 96 patients (26%), most frequently during the first year after transplantation. Female recipients had significantly more UTI than male recipients (49% vs. 14%, p < 0.0001). There was no difference in the incidence of UTI between recipients receiving pig-tail catheters as ureteral stents or not, the figures being 21% vs. 28%, respectively. Age had no influence on the incidence of UTI. In 341 patients treated with cyclosporine the incidence of UTI was 28%, while in 15 patients treated with FK-506 only 1 patient (7%) had a UTI (ns). The majority of organisms cultured were gram-negative (76%), with approximately 1/3 being Escherichia coli and 1/5 being Enterococcus and Klebsiella/Enterobacter. The bacterial spectrum was not influenced by the recipients age. UTI had no effect on the number of rejections, or on graft and patient survival in living donor transplant recipients. No significant difference was found in graft and patient survival rates at 3 yr between patients who had UTI or no UTI.

Risk group stratification to predict recurrence after transurethral resection in Japanese patients with stage Ta and T1 bladder tumours: validation study on the European Association of Urology guidelines

Study Type – Therapy (case series) 
Level of Evidence 4

Collecting duct carcinoma with long survival treated by partial nephrectomy

Abstract A case is reported of collecting duct carcinoma of the left kidney treated with partial nephrectomy. A 57‐year‐old woman presented for evaluation of the left renal mass, which was detected by screening ultrasonography. A computed tomography scan and magnetic resonance imaging showed a solid mass at the upper pole of the left kidney. The renal tumor biopsy revealed a low‐grade renal cell carcinoma or a tubulopapillary adenoma. Subsequently, left partial nephrectomy was performed. Microscopically, the tumor showed tubulopapillary proliferation with a fibrous capsule. Histochemically, the tumor cells reacted with lectins or antibodies against the collecting duct. Twenty‐four months after partial nephrectomy, the patient is alive and has no distant metastatic lesions. We review the literature on collecting duct carcinoma, in addition to the case of partial nephrectomy.

Expression of thymidine phosphorylase in human superficial bladder cancer

Abstract Background:  The purpose of the present paper was to investigate the expression level of thymidine phosphorylase (TPase) in superficial bladder cancer tissues obtained by transurethral resection, and determine whether its expression correlates with tumor recurrence.

Effects of tacrolimus on rat thymic epithelial cells.

FK506 is an immunosuppressive agent that was discovered in Japan. Many experiments on organ transplantation have shown the prolongation of allograft survival in animals by treatment with FK506. Previous studies have also shown that FK506 has a remarkable immunosuppressive effect and improves the outcome of liver transplantation. We recently analyzed the effect of FK506 on thymocyte differentiation by the immunoperoxidase technique and flow cytometry using monoclonal antibodies (MoAbs) for thymus and T-cell surface antigens, and we found a reduction of major histocompatibility complex (MHC) class II antigen expression on thymic epithelial cells. Our results have suggested that FK506 inhibited thymocyte differentiation in rats by not only directly but also by indirectly acting on thymic epithelial cells. In the present study, we investigated the effect of FK506 on rat thymic epithelial cells by immunohistochemistry using various MoAbs.

Novel prophylactic effect of doxifluridine in superficial bladder cancer

Objectives: The prophylactic effect of 5′-deoxy-5-fluorouridine (5′-DFUR) has not been fully studied in superficial bladder cancer. The aims of this work were to investigate the prophylactic effects of 5′-DFUR in terms of tumor recurrence after transurethral resection of bladder tumor (TURBT) and to study whether thymidine phosphorylase (TdRPase) immunostaining predicts tumor recurrence. Material and Methods: A total of 112 patients with pTa or pT1 bladder cancer were eligible for the analysis and were allocated to either an adjuvant group (TURBT+5′-DFUR; n=47; initial 23 months) or a control group (TURBT alone; n=65, final 23 months). Tumor specimens were studied immunohistochemically using anti-TdRPase antibody. Results: Tumor recurrence was observed in 54 of the patients (48%) after a median follow-up period of 26.8 months. No significant clinico-pathologic bias was observed between the two groups. Although patients in the adjuvant group had a significantly higher recurrence-free survival rate than those in the control group when considering 78 patients with pathological T1 tumors (p=0.0272) and 65 patients who did not recur within 12 months (p=0.001), overall there was no significant difference between the two groups. Multivariate analysis revealed that 5′-DFUR administration was the strongest predictor of late tumor recurrence, which was defined as development of recurrence 12 months after TURBT (hazard ratio 5.744; 95% CI 1.495-30.45; p=0.0094). Immunostaining did not predict prophylactic effects of 5′-DFUR. Mild, reversible toxicity was found in 9/58 (15.5%) of the cases evaluated. Conclusions: Oral administration of 5′-DFUR after TURBT did not prevent tumor recurrence in the overall cohort, although this novel drug may have a prophylactic effect in patients belonging to several subgroups.