Yoji Katsuoka

Bactericidal activity of electrolyzed acid water from solution containing sodium chloride at low concentration, in comparison with that at high concentration.

Electrolyzed strong acid water (ESW) containing free chlorine at various concentrations is becoming to be available in clinical settings as a disinfectant. ESW is prepared by electrolysis of a NaCl solution, and has a corrosive activity against medical instruments. Although lower concentrations of NaCl and free chlorine are desired to eliminate corrosion, the germicidal effect of ESW with low NaCl and free-chlorine concentrations (ESW-L) has not been fully clarified. In this study, we demonstrated that ESW-L possesses bactericidal activity against Mycobacteria and spores of Bacillus subtilis. The effect was slightly weaker than that of ESW containing higher NaCl and free-chlorine concentrations (ESW-H), but acceptable as a disinfectant. To clarify the mechanism of the bactericidal activity, we investigated ESW-L-treated Pseudomonas aeruginosa by transmission electron microscopy, a bacterial enzyme assay and restriction fragment length polymorphism pattern (RFLP) assay. Since the bacterium, whose growth was completely inhibited by ESW-L, revealed the inactivation of cytoplasmic enzyme, blebs and breaks in its outer membrane and remained complete RFLP of DNA, damage of the outer membrane and inactivation of cytoplasmic enzyme are the important determinants of the bactericidal activity.

EXPRESSION OF ENDOTHELIN RECEPTOR A ASSOCIATED WITH PROSTATE CANCER PROGRESSION

PURPOSE We determined the role of endothelin receptors in prostate cancer progression. MATERIALS AND METHODS We examined 51 prostate cancer specimens obtained at surgery or biopsy for the relationship of endothelin receptor expression determined by immunohistochemical staining with malignant potential. RESULTS The positive staining rate of endothelin receptor A in the 51 specimens was significantly higher than of endothelin B (71% versus 24%, p <0.0001). The staining rate of receptor A in Gleason score 5 to 10 disease was significantly higher than in Gleason 2 to 4 disease (91% versus 29%, p <0.0001). The overall staining rate of endothelin receptor A in nonorgan confined disease without bone metastasis but with extraprostatic disease was 87% in 23 cases, including 16 of 19 stage T3 (84%) and all 4 stage T4 (100%) cases. This rate was significantly higher than that of organ confined cancer (29%, p = 0.0003). All patients with bone metastasis had positive staining for endothelin receptor A. An especially high rate of intensely positive staining was observed for endothelin receptor A in biopsy specimens with bone metastasis or Gleason sum 8 to 10. Moreover, positive staining was stronger in cancer cells penetrating the prostatic capsule than in those at the primary foci. However, the positive staining rate of endothelin receptor B was not significantly different in organ and nonorgan confined cancer without bone metastasis (12% versus 26%, p = 0.4284), bone metastatic and nonmetastatic cancer (20% versus 36%, p = 0.2619) or the Gleason sum groups (p = 0.0874). CONCLUSIONS Our results indicate that endothelin receptor A expression may serve as a marker for and have an important role in prostate cancer progression.

Expression of three extracellular matrix degradative enzymes in bladder cancer

The relationship between expression of extracellular matrix degradative enzymes, angiogenesis and survival of multistage bladder cancer was determined. Expression of 3 extracellular matrix degradative enzymes (metalloproteinase‐2, ‐9 and heparanase) and microvessel formation were examined in 40 resected bladder cancer specimens by immunohistostochemic staining, and then the association of the enzyme expression with angiogenesis and various stages of cancer was investigated. Heparanase protein expression in muscular invasive or lymph‐node metastatic cancer was significantly higher than in superficial or nonmetastatic cancer, respectively (69% vs. 8%, p < 0.001, and 80% vs. 40%, p = 0.028, respectively). Interestingly, heparanase was expressed at much higher levels than matrix metalloproteinase‐2 and ‐9. The mean microvessel count in cancers with heparanase expression was significantly higher than that in cancers without heparanase expression (32.3 ± 18.2 vs. 5.5 ± 6.1, p = 0.0008). The microvessel formation was not associated with the expression of matrix metalloproteinase‐2 and ‐9. The cancer‐specific and overall survival rates of patients with heparanase expression were significantly lower than those of patients without it (p = 0.0001 and p = 0.0008, respectively). Multivariate analysis showed that heparanase expression was a significantly independent prognostic factor for both cancer‐specific (p = 0.0047) and overall survival (p = 0.0200). Our study suggested that heparanase plays important roles in invasion, angiogenesis and metastasis of bladder cancer, and thus, this molecule could be a new molecule to inhibit invasion, angiogenesis and metastasis of bladder cancer. Moreover, our results indicate that expression of heparanase could be a new prognostic factor of this disease.

HEPARANASE PROTEIN AND GENE EXPRESSION IN BLADDER CANCER

PURPOSE We determined the association of heparanase protein and messenger (m)RNA expression with bladder cancer invasion and metastasis. MATERIALS AND METHODS The expression of heparanase protein and mRNA was assessed by immunohistochemical staining and in situ hybridization, respectively, in 67 bladder cancer specimens resected at various stages of disease. To our knowledge this is the first systematic study of heparanase protein and mRNA expression in human bladder cancer. RESULTS The expression of heparanase protein in muscular invasive bladder cancer was significantly higher than in superficial cancer (68% versus 19%, p = 0.0001). It was higher in the primary tumor of patients with lymph node metastatic cancer than those with nonmetastatic cancer (80% versus 37%, p = 0.0006). In high grade disease it was significantly higher than in low grade disease (79% versus 29%, p = 0.0001). The expression of heparanase mRNA was also significantly higher in stage pT3 or greater than in stage pT2 or less bladder cancer (96% versus 33%, p = 0.0003). In metastatic N+ cases it was significantly higher than in nonmetastatic bladder cancer (93% versus 46%, p = 0.0037). The heparanase gene and protein showed similar patterns of expression in bladder cancer. CONCLUSIONS Our study implies that the expression of heparanase protein and mRNA is associated with bladder cancer invasion and metastasis, and heparanase may have a role in disease progression.

Prognostic significance of neuroendocrine differentiation, proliferation activity and androgen receptor expression in prostate cancer

Androgen, acting via the androgen receptor (AR), is associated with the development and progression of prostate cancer. Anti‐androgen therapy is widely used to manage prostate cancer. However, the conversion of the tumor from a hormone‐sensitive to a hormone‐insensitive status causes such therapy to fail. Several mechanisms have now been put forward for this conversion, including neuroendocrine (NE) differentiation of the tumor cells. In this study, we evaluated the prognostic significance of tumor‐cell proliferation activity, NE differentiation and AR expression. Formalin‐fixed, paraffin‐embedded sections were prepared from 42 patients with adenocarcinoma of the prostate. Using antibodies to AR, the Ki‐67 antigen (MIB‐1), chromogranin A and synaptophysin, immunohistochemical expression of AR, tumor proliferation activity and NE differentiation were analyzed. Our study revealed that AR expression was significantly lower in adenocarcinoma (52.2 ± 27.1%) than in non‐tumorous prostate tissue (68.3 ± 18.3%; P < 0.001). NE differentiation was found in 50% of the tumors, which was correlated with the Gleason score (P < 0.05). An univariate analysis revealed a significant correlation between progression‐free survival with both AR expression (P < 0.01) and proliferation activity (P < 0.001). NE differentiation was not a prognostic factor in this study.

Disinfection potential of electrolyzed solutions containing sodium chloride at low concentrations

Electrolyzed products of sodium chloride solution were examined for their disinfection potential against hepatitis B virus (HBV) and human immunodeficiency virus (HIV) in vitro. Electrolysis of 0.05% NaCl in tap water was carried out for 45 min at room temperature using a 3 A electric current in separate wells installed with positive and negative electrodes. The electrolyzed products were obtained from the positive well. The oxidation reduction potential (ORP), pH and free chlorine content of the product were 1053 mV, pH 2.34 and 4.20 ppm, respectively. The products modified the antigenicity of the surface protein of HBV as well as the infectivity of HIV in time- and concentration-dependent manner. Although the inactivating potential was decreased by the addition of contaminating protein, recycling of the product or continuous addition of fresh product may restore the complete disinfection against bloodborne pathogens.

AST-120 Treatment in Pre-Dialysis Period Affects the Prognosis in Patients on Hemodialysis

Background/Aims. An oral adsorbent, AST-120, has been shown to retard the deterioration of renal function in patients with chronic kidney disease (CKD) by decreasing serum nephrotoxic substances such as indoxyl sulfate. Recent studies have suggested that a high level of serum indoxyl sulfate may be one of the mechanisms underlying the progression of atherosclerotic lesion, which is the leading cause of cardiovascular event or death in dialysis patients. In this study, we examined retrospectively whether AST-120 given to patients in the pre-dialysis period influences the prognosis after the initiation of dialysis. Methods. One hundred and ninety-two CKD patients on dialysis were studied. The survival and causes of death after the initiation of dialysis were compared between patients who were administrated AST-120 (AST-120 group, n = 101) and those not administrated AST-120 (non-AST-120 group, n = 91) prior to the initiation of dialysis. Results. The five-year survival rate was 72.6% in the AST-120 group and 52.6% in the non-AST-120 group, and was significantly higher in the AST-120 group (p = 0.018). The risk of death was increased 1.91-fold in the non-AST-120 group. However, no difference in the causes of death was observed between two groups. Conclusion. This study suggests that AST-120 given prior to the initiation of dialysis improves the prognosis of CKD patients under dialysis, although there is no association between AST-120 treatment and death caused by cardiovascular diseases such as heart failure, myocardial infarction, and cerebral hemorrhage. Further studies are needed to elucidate the effect of AST-120 on cardiovascular events and the prognosis in dialysis patients.

AST-120, an oral adsorbent, delays the initiation of dialysis in patients with chronic kidney diseases.

Abstract:  The effects of an oral adsorbent, AST‐120, in chronic kidney disease (CKD) patients was evaluated by the 24‐month dialysis‐free rate and 50% dialysis‐free period. This study retrospectively analyzed 193 patients admitted to the Osaka Medical College Hospital between January 1994 and December 2001 because of CKD and who later started dialysis. The propensity score on multiple factors was used to match two groups of patients (AST‐120 group, n = 78; non‐AST‐120 group, n = 78). Then, the proportion of patients remaining dialysis‐free and the 50% dialysis‐free period during the 24 months after starting treatment with or without AST‐120 were analyzed. The impact of AST‐120 on the risk of dialysis initiation was also determined by multivariate analysis. There were no significant differences in the clinical background and laboratory values after matching the two groups using the propensity score. The 50% dialysis‐free period was significantly prolonged in the AST‐120 group compared to the non‐AST‐120 group for all patients analyzed, as well as for the subgroup with diabetic or non‐diabetic renal disease. When AST‐120 treatment was started at a serum creatinine level below 3 mg/dL, the dialysis‐free period was longer than 24 months in the AST‐120 group, compared with 16.2 months in the non‐AST‐120 group. The 24‐month dialysis‐free rate was higher in the AST‐120 group in every patient category. The risk of dialysis initiation was increased 3.48‐fold in patients who were not administered AST‐120. These results show that AST‐120 delays the initiation of dialysis in CKD patients. Thus, AST‐120 is an effective supplementary therapy to prevent the initiation of dialysis in CKD patients.

Independent Prognostic Value of Serum Hepatocyte Growth Factor in Bladder Cancer

PURPOSE We retrospectively investigated whether the level of serum hepatocyte growth factor could predict the prognosis and extent of transitional-cell carcinoma of the urinary bladder. PATIENTS AND METHODS Serum samples were collected from 113 patients with bladder cancer and from 200 healthy controls. Of the 113 patients, 59 had superficial bladder cancer and 54 had muscle-invasive cancer. Thirteen bladder cancer tissues (eight superficial and five muscle-invasive) were also collected. The levels of hepatocyte growth factor in the serum and tissues of these individuals were measured by enzyme-linked immunoadsorbent assay using hepatocyte growth factor antibodies. RESULTS The levels of hepatocyte growth factor in the serum and tissues of patients with muscle-invasive cancer were significantly higher than those of patients with superficial bladder cancer (P <.0001 and P =.0054, respectively). The degree of elevation above the normal level of serum hepatocyte growth factor of the former (61.1%) was significantly higher than that of the latter (8.4%; P <.0001). The elevation was highest in patients with visceral metastasis (93.3%). Among patients with superficial bladder cancer, the overall survival rate of those with low levels of serum hepatocyte growth factor was significantly greater than that of those with high levels (P =.005). Among patients with minimally invasive bladder cancer, the disease-free and overall survival rates of those with high levels of serum hepatocyte growth factor were significantly lower than the same rates of those with low levels (P <.001 and P =.0028, respectively). CONCLUSION Our study suggests that the level of hepatocyte growth factor in serum could be a predictor of patient survival and extent of bladder cancer.

Expandable metallic stent placement for nutcracker phenomenon

A 40-year-old woman presented with asymptomatic gross hematuria caused by the nutcracker phenomenon. Despite treatment with hemostatic agents and injection of silver nitrate into the renal pelvis, the hematuria had continued, and severe anemia (hematocrit 17%) had developed. We performed expandable metallic stent (EMS) placement across the left renal vein. Although mild hematuria continued, the anemia resolved after this interventional radiotherapy. EMS placement is a minimally invasive therapy for the nutcracker phenomenon.