George R. Nagamatsu

Ureteral Replacement Using Collagen Sponge Tube Grafts

The use of a collagen sponge tube graft as a material for segmental ureteral replacement was investigated. The structural design of the collagen sponge graft was achieved by cell culture on the matrix. MGH-U1 cells, derived from bladder cell carcinoma, were grown in vitro on the collagen sponge matrix with excellent biocompatibility and without evidence of cytotoxicity. The collagen sponge demonstrated biodegradability when implanted subcutaneously in dogs. However, a urine exposure test of collagen sponge in rat bladders revealed extensive salt deposits on its surface in some rats, as observed by crystallographic examination. Segmental ureteral replacements by collagen sponge tube grafts, accompanied by ureteral splint catheters, were performed in dogs. There was extensive uro-epithelial cell regeneration on the inner surface of the collagen grafts, without evidence of severe hydronephrosis, 5 to 12 weeks following the procedure. The results indicate the potential for ureteral replacement by collagen sponge tube grafts, which would act as non-toxic, biodegradable scaffolds inducing the regenerative activity of the ureter.

Establishment of new human prostatic cancer cell line (JCA-I)

The establishment of a new human prostatic cancer cell line is described. This cell line was derived from a poorly to moderately differentiated prostatic adenocarcinoma. It has been maintained in tissue culture for fourteen months and has been passed fifty-two times. This cell line has an ability to form colonies in soft agar suspension cultures, and also is transplantable to nude mice. Tumors grown in nude mice revealed a poorly differentiated adenocarcinoma with positive PSA staining. Acid phosphatase activity was detected in freeze-thawed cells by enzymatic assay. A karyotype analysis demonstrated aneuploidy with a model chromosomal number of 69 and six marker chromosomes.

Application of microwave tissuecoagulation in partial nephrectomy

Abstract Microwave tissue coagulation was used during partial nephrectomy in 10 mongreldogs, without clamping the renal artery. There were no major complications, such as retroperitoneal hematoma, abscess formation, or macroscopic infarction of the kidney tissue related to this new procedure. The advantages of microwave coagulation are reduced blood loss, shorter operative time, and minimal risk of vascular injury.

Retroperitoneal leiomyomapresenting as prostatic mass

Abstract A case of retrovesical retroperitoneal leiomyoma presenting as a prostatic mass isreported. This tumor is rarely found in the retroperitoneum and is even rarer in the retrovesical space.

Heterogeneity index score (HIS): New computerized method for classification of human bladder carcinomas using flowcytometry

The rationale for studying nuclear DNA may be its direct relationship to the aggressiveness of cancer. Recent flow cytometric studies (FCM) of cancer cells show the limitation of the current methods for the accurate determination of the degree of aneuploidy or proliferative characteristics of a tumor cell. Here we report a new methodology for a computerized determination which is well correlated with relative mean DNA content in cell populations analyzed by FCM (heterogeneity index, HI). A total of seventy-six tissue samples were examined. Twenty-two specimens were benign tissue while fifty-four were histologically malignant bladder tumors. Forty tumors were grade (G)I-II, ten G-III, and four carcinoma in situ. The samples were mechanically minced into a single cell suspension and stained with propidium iodide. An Ortho system 50-H multiparameter flow cytometer equipped with an Ortho 2150 computer was used to determine DNA content and cell number. HI was calculated using the following formulas: (formula; see text) The mean HIS of twenty-two normal and benign tissues was 9.805 +/- 5.6. The forty G-II tumors had a mean HIS of 23.576 +/- 26.519. Statistical differences were observed between benign tissue and G-I-II tumors (P = 0.0196). G-III tumors had a marked increase in HIS of 160.965 +/- 63.404. The limited study of four carcinoma in situ tumors showed a mean HIS of 45.4 +/- 9.5. Our computer extrapolation of flow cytometric DNA analysis quantifies an objective description of FCM characteristics and histochemical index which may distinguish the degree of tumor malignancy.

Scientific articleHeterogeneity index score (HIS): New computerized method for classification of human bladder carcinomas using flowcytometry☆

The rationale for studying nuclear DNA may be its direct relationship to the aggressiveness of cancer. Recent flow cytometric studies (FCM) of cancer cells show the limitation of the current methods for the accurate determination of the degree of aneuploidy or proliferative characteristics of a tumor cell. Here we report a new methodology for a computerized determination which is well correlated with relative mean DNA content in cell populations analyzed by FCM (heterogeneity index, HI). A total of seventy-six tissue samples were examined. Twenty-two specimens were benign tissue while fifty-four were histologically malignant bladder tumors. Forty tumors were grade (G)I-II, ten G-III, and four carcinoma in situ. The samples were mechanically minced into a single cell suspension and stained with propidium iodide. An Ortho system 50-H multiparameter flow cytometer equipped with an Ortho 2150 computer was used to determine DNA content and cell number. HI was calculated using the following formulas: (formula; see text) The mean HIS of twenty-two normal and benign tissues was 9.805 +/- 5.6. The forty G-II tumors had a mean HIS of 23.576 +/- 26.519. Statistical differences were observed between benign tissue and G-I-II tumors (P = 0.0196). G-III tumors had a marked increase in HIS of 160.965 +/- 63.404. The limited study of four carcinoma in situ tumors showed a mean HIS of 45.4 +/- 9.5. Our computer extrapolation of flow cytometric DNA analysis quantifies an objective description of FCM characteristics and histochemical index which may distinguish the degree of tumor malignancy.

Monocyte cytolytic factor in promoting monocyte-mediated lysis of bladder cancer cells by bacillus Calmette-Guerin.

The role of monocytes in cell-mediated cytolysis of bladder cancer cells was investigated. Human peripheral monocytes released a cytolytic factor which lysed T24 bladder cancer cells and a number of human tumor cells, but not normal lymphocytes or fibroblasts. After incubation of monocytes with bacillus Calmette-Guerin for 48 hr. in vitro, cytolysis of T24 cells was increased up to 56.7 +/- 4.1%. Treatment of monocytes with actinomycin D (an inhibitor of RNA transcription) reduced release of cytolytic factor from 27.3 +/- 5.7% cytolysis to 4.5 +/- 1.4% (p less than 0.05). The response to mitomycin C was different between lymphokines and monocyte cytolytic factor. The mouse monoclonal antibody against human recombinant tumor necrosis factor did not neutralize monocyte cytolytic factor. These results show that this monocyte cytolytic factor is distinct from lymphokines and tumor necrosis factor. The evidence that bacillus Calmette-Guerin increases release of monocyte cytolytic factor may be associated with anti-tumor activity of bacillus Calmette-Guerin in intravesical therapy for treatment of bladder cancer.

Depressed myocardial function after transurethral resection of prostate.

Cardiovascular physiologic monitoring was undertaken in 12 patients undergoing transurethral resection of the prostate with the aid of flow-directed Swan-Ganz catheter and the Automated Physiologic Profile. Cardiac and pulmonary pressures and physiologic parameters were derived pre- and postoperatively. Resecting time, body temperature, intravenous fluid administered, serum hemoglobin, and sodium also were recorded. Of the 12 patients studied, 66 per cent experienced a drop in their cardiac index as well as their left ventricular function after surgery. Myocardial function curves revealed that 7 patients (58 per cent) had decreased cardiac function, 2 had no change, and 3 had increased function. Four patients with preoperative pulmonary wedge pressures (PAW) over 9 mm. Hg experienced depressed cardiac function. Three patients were resected for over sixty minutes, and all experienced depressed cardiac function. Vital signs, serum hemoglobin, or serum sodium did not reflect this change. We believe that relative hypervolemia, undetected elevation of pulmonary wedge pressure. We believe that relative hypervolemia, undetected elevation of pulmonary wedge pressure, and prolonged resection are factors that depress cardiac function and increase the risk of cardiovascular complication in transurethral surgery.

Immunosuppressive factor derived from renal cancer cells

An immunosuppressive factor derived from conditioned medium of a human renal cancer cell line, KU2, was analyzed, using mitogen-activated normal peripheral blood lymphocytes. Addition of conditioned medium to lymphocyte cultures resulted in suppression of [3H]-thymidine incorporation to DNA of lymphocytes in a dose-dependent manner. This effect was cytostatic and reversible. This factor inhibited lymphocyte activation stimulated by mitogen at an early stage, and it also suppressed Interleukin-2 production by activated lymphocytes. This factor was non-dialyzable and heat sensitive at 56 degrees C. DNA replication of the cells was necessary for the production of this factor.

Flow cytometric analysis of relative mean DNA content of urogenital cancer cells in fresh and paraffin-embedded materials

The relative mean DNA content calculation was performed by flow cytometry on single cell suspensions prepared from fresh and paraffin-embedded specimens of 10 patients with surgically resected urogenital cancer. Samples were processed by a modified method of Hedley et al. including two hours of pepsinizing time, ribonuclease digestion, and propidium iodide staining. The mean DNA content which is a quantitative description of flow cytometric characteristics was significantly correlated between the fresh and paraffin-embedded materials (n = 10, r = 0.869, p less than 0.01). This method allows for the objective, retrospective analysis of DNA content in relation to diagnosis and prognosis of urogenital cancer.