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Biomedical subjects

T Ohkawa

Publications and source records attributed to T Ohkawa.

At least 145 records · Page 8Linked to original sources
PubMed1989

[Basal studies on combination of Chinese medicine in cancer chemotherapy: protective effects on the toxic side effects of CDDP and antitumor effects with CDDP on murine bladder tumor (MBT-2)].

Effects of oral administration of Juzentaihoto, a herb drug, on the toxic side effects of cis-diammine dichloroplatinum (CDDP) and combination effects with CDDP on murine bladder tumor (MBT 2) were studied using C3H/He male mice. The following results were obtained; 1. When the mice were treated with the mixture diet of 1% or 0.5% Juzentaihoto before 2 weeks, adverse effects of high dose CDDP (15 or 17.5 mg/kg) which were included with lethal toxicity, renal and hepatic toxicity, and myelosuppression were protected significantly. The administration of 0.5% Juzentaihoto mixture diet markedly shifted the LD50 to the right. Furthermore, the effects of Juzentaihoto were clearly revealed on the histological findings of testis and kidney. 2. On murine bladder tumor, when the mice were treated with the mixture diet of 1% or 0.5% Juzentaihoto and injected CDDP (2.5 mg/kg/week) for 8 weeks, significantly greater inhibition of the tumor growth and prolongation of the survival rate were observed than those in the group of CDDP alone. These results indicates that Juzentaihoto lessens the toxic side effects of CDDP and that it enhances the effects of CDDP experimentally. Juzentaihoto, a kind of Chinese herb medicine, might come under the category of biological response modifiers.

Administration, Oral↗
PubMed1989

Nephrectomy in situ: treatment of ureteral fistula due to progressive malignancy.

The authors report 2 patients with recurrent retroperitoneal neoplasms in whom ureteral fistulas were treated successfully by percutaneous transcatheter embolization of the renal artery with absolute ethanol. Angio-occlusive nephrectomy is suggested as an alternative to surgical nephrectomy in seriously ill and high-risk patients to preserve their quality of life.

Aged↗
PubMed1989

Urethral remnant tumors following simultaneous partial urethrectomy and cystectomy for bladder carcinoma.

Partial urethrectomy (at least to the bulbous portion) was performed simultaneously in 128 consecutive male patients undergoing radical cystectomy for bladder cancer. Transitional cell carcinoma developed subsequently in the distal urethral remnant in 5 patients (4.0%) followed for 2.6 to 5.7 years (mean 4.1 years) postoperatively. These 5 patients originally had nonpapillary, multifocal and histologically high grade (5) and low stage (4) bladder cancer, 4 with associated carcinoma in situ. Our results suggest that simultaneous total urethrectomy should be considered strongly for patients with high grade nonpapillary multifocal bladder cancer associated with carcinoma in situ. Furthermore, the pattern of distal urethral recurrence in our patients may provide information regarding the appropriate management of the male urethra in potential candidates for continent urinary diversion.

Aged↗
PubMed1989

Sex-specific effects on the fetal neuroendocrine system during acute stress in late pregnancy of rat and the influence of a simultaneous treatment by tyrosine.

It is well-known that prenatal chronic intermittent stress affects the reproductive system of both sexes. Investigating the effects of an acute maternal stress on the fetal neuroendocrine system, parameters such as hypothalamic catecholamines. CRF, GRF, LH-RH, beta-endorphin, hypophysial beta-endorphin and beta-LPH as well as plasma LH, corticosterone and androstenedione were measured. Pregnant rats of Wistar strain were exposed to restraint stress at day 22 of gestation or to forced immobilization at day 20 of gestation, respectively, and were sacrificed before stress and 10, 30, 60, and 120 min after starting stress. A decrease of fetal hypothalamic catecholamines and an increase of LH-RH content of the hypothalamus as well as of plasma catecholamines were observed under stress on day 22 of gestation. On day 20 of gestation hypothalamic beta-endorphin was depleted in male and unchanged in female fetuses under stress. A depletion of hypothalamic CRF was observed in male fetuses, whereas female fetuses showed an increase of hypothalamic CRF. An increase of GRF was found in fetuses of both sexes. Pituitary opioid content increased in fetuses of both sexes initially, but was depleted secondarily in male fetuses. The LH plasma level was markedly reduced in male, the corticosterone level was elevated in fetuses of both sexes as well as the androstenedione level in female fetuses. A simultaneous treatment of mother animals with tyrosine--a catecholamine precursor--prevented the depletion of hypothalamic and pituitary beta-endorphin as well as in part the reduction of plasma LH levels in male fetuses. Hypothalamic GRF content does not increase under tyrosine treatment in male fetuses, whereas in female fetuses the stress-induced increase of GRF content was rather pronounced under tyrosine than attenuated. These results indicate that fetal hypothalamic neurotransmitters and neurohormones (such as LH-RH, CRF, GRF and opioids) are involved in changing circulating hypophysial and adrenal hormones in fetuses exposed to maternal stress in late pregnancy, whereby sex-specific different pathways might be effective in fetal stress processing. The prenatal administration of tyrosine prevented at least in part--those neurohormonal changes which are affecting the sex-specific brain differentiation.

Androstenedione↗
PubMed1989

Comparative antitumor activity of 5-fluorouracil and 5'-deoxy-5-fluorouridine in combination with radiation therapy in mice bearing colon 26 adenocarcinoma.

The present study compared the antitumor activities of chemotherapy with 5-fluorouracil (5-FU) and with its prodrug 5'-deoxy-5-fluorouridine (5'-DFUR) in combination with radiotherapy on a solid colon 26 adenocarcinoma in the mouse. A single administration of 5'-DFUR immediately after local irradiation on day 10 after tumor inoculation produced more than additive antitumor effects, while only an additive effect was observed in the combined treatment with 5-FU and radiation. This over-additive effect of 5'-DFUR was more obvious in a fractionated-dose treatment schedule, where the same combined modality treatment was given three times on days 6, 10 and 14 after inoculation of the tumor cells. 5'-DFUR enhanced the radiation effects on the tumor in terms of the delay in tumor growth as well as the increase in the survival time. 5-FU produced only a marginal additive antitumor effect. Furthermore, radiation damage to normal tissues (skin damage by local irradiation and bone marrow and spleen damage by whole-body irradiation) was not enhanced by 5'-DFUR, though radiation damage to the thymus was additive. On the other hand, 5-FU produced toxic effects that were additive for all normal tissues tested. Thus, at doses that were the most effective against tumors, relative therapeutic gain factors (the ratio of the effect on tumors to that on the bone marrow) of 5'-DFUR and 5-FU were 1.24 and 0.49, respectively. These results suggest that 5'-DFUR will have a greater potential than 5-FU in combined modality treatment of cancer patients.

Adenocarcinoma↗
PubMed1989

The inhibitory effect of synthetic steroids on proestrous gonadotropin release in the rat.

This study was performed to evaluate the inhibitory effect of synthetic steroids on the hypothalamo-pituitary axis. Six synthetic steroids, used for contraception or other gynecologic indications, were injected to female rats on diestrus 2 (2 mg/kg, sc), and the animals were sacrificed in the afternoon of proestrus. Serum levels of LH, FSH and progesterone, the pituitary contents of LH and FSH, and LH-RH in the median eminence were measured by radioimmunoassays. Among the synthetic steroids tested in this study, norethisterone, d-norgestrel, 3-keto-desogestrel and gestrinone completely blocked the gonadotropin surge on proestrus, showing stronger antigonadotropic activity than progesterone. Desogestrel did not affect proestrous gonadotropin release at this dose. The suppressive effect of danazol could be seen only in a larger dose (20 mg/kg). These findings reconfirmed previously reported results, which demonstrated that the hypothalamo-pituitary complex was a major site of action of these steroids.

Animals↗
PubMed1989

Intravesical Bacillus Calmette-Guérin treatment for superficial bladder tumours.

Intravesical instillations of Tokyo 172 strain BCG were given to 56 patients with superficial bladder cancer during the 24-month period after transurethral tumour resection as a prophylaxis against tumour recurrence. The recurrence rate of tumours was compared with that of historical controls. Results were estimated by the person-years method and there were statistically significant decreases in recurrent tumours following BCG therapy. Our results suggest that the intravesical Tokyo 172 strain BCG is effective and safe as a prophylaxis against the recurrence of superficial bladder tumours.

Administration, Intravesical↗
PubMed1989

[Urinary calculous disease--a saga of urological field in Japan].

The management of urinary calculous disease has been a treasured place also in urological history of Japan. Recently, innovatory procedures for stone removal have been introduced and the excellent advances of Endourology and ESWL (extracorporeal shock wave lithotripsy) revolutionized the surgical treatment of renal calculous disease. However, some thoughtful members of urologists have been afraid that the majority of the urological surgeons might believe if they have already completed the treatment of urolithiasis and succeeded the resolution on the patients with renal calculous disease. Now, I will write a saga of the investigations of this interesting and still important subject in the urological field of Japan, looking back my own way who have been interested in urolithiasis treatment and also its prophylaxis. The goal of the treatment for urinary calculous patients should be the prevention of recurrent stone formation because the surgical treatment is only the removal of existing stones, even recent advance of innovatory procedures could confer the less invasive benefits on urinary calculous patients. Some selective medical treatment programs have been introduced and emerged therapeutic importance to the prevention of renal stone formation and more will have elaborated in the future. Several investigations on the difficult mechanisms of stone formation have been also vigorously accomplishing by some urologists in Japan. I hope that I would anticipate what is to come on the entire solution of the precise mechanism of stone formation and ultimate control of urolithiasis by successional young urologic investigators in near future.

Humans↗
PubMed1989

[Occupational uroepithelial cancer: current status in Wakayama city and clinical study].

According to the records of Wakayama Labor Standard Office, at least 1,085 workers had been exposed to benzidine or beta-naphthylamine in the dyestuff factories in Wakayama City. By October 1988, 101 of them (9.3%) were confirmed to have urinary tract tumors. Including 2 other cases exposed in Osaka, a total of 103 cases of occupational uroepithelial cancer were studied here clinically. Site of tumors was bladder in 91 cases, renal pelvis in 2, ureter in 5 and papillomatosis type in 5. The age at the time of diagnosis ranged from 25 to 87 years with a mean of 53.8 years. The average latent period was 22.7 years, but the older the age of the worker at the start of exposure, the shorter was the latent period. In Wakayama, the proper system of healthy examination for chemical workers using urinary cytology was begun in 1970. Since then, more tumor cases have been discovered in comparison to the patients admitted with subjective symptoms of hematuria. The effectiveness of this group examination was significant in the incidence of total cystectomy in surgical treatment and in survival rate. In the comparative study between the groups of patients with occupational and spontaneous bladder cancer, the average age at diagnosis in the former was about ten years younger. Although the histological grade of tumor was not different between the two groups, the incidence of total cystectomy was lower and the survival rate was significantly higher in the occupational group.

2-Naphthylamine↗
PubMed1989

[A clinical study of the radiosensitization of aclarubicin].

Sixty six patients with an advanced or a relapsed cancer have been treated with a combination of radiation and aclarubicin (ACR). The average irradiation dose was 45 +/- 15 Gy, and the combined total dose of ACR ranged from 130 to 260 mg, depending upon the following differing schedules: 10 mg x 3 or 5/w, 20 mg x 2 or 3/w and 20 mg x 2/d x 2/w. The tumor response attained was 70%, including 30% who achieved a complete response. A high response rate also was observed in rather radioresistant cancerous tumor, such as those of the lung, stomach and esophagus. The adverse effects, such as anorexia, nausea, and so on, were found increase with an increase in the dose of ACR. It thus was concluded that for clinical usefulness, 10 mg of ACR should administered every other day in combination with a definite program of radiotherapy.

Aclarubicin↗
PubMed1989

[The history of radiotherapy of breast cancer].

Radiotherapy has come to be an important resource in the treatment of breast cancer. After the discovery of X-ray in 1985, postoperative irradiation has been important in selected patients who have undergone mastectomy and locoregional irradiation for postoperative recurrence has proved to be beneficial. Although histology of the breast cancer is adenocarcinoma, it is radiosensitive. The role of radiotherapy has shifted from surgical adjuvant therapy to definitive management in an effort to preserve esthetics and function.

Adenocarcinoma↗
PubMed1989

[Comparison of surgical therapy and combined irradiation in rectal cancer--first report, effect of irradiation on the tumor. Study Group of Surgical Therapy and Combined Irradiation in Rectal Cancer].

In order to establish the best protocol for the treatment of rectal cancers, a cooperative study on preoperative radiation therapy was conducted by 44 institutions in eastern Japan. A total of 166 cases that did not receive preoperative chemotherapy were analyzed, and the following conclusions were obtained. A comparison between two groups of patients, one that had received preoperative irradiation and the other that had not, revealed remarkable tumor regression in the former along with reduction of in rectal stenosis, condition of the border of the lesion, bleeding, constriction and central excavation. There were no significant differences between the two groups in terms of lymph node metastasis. Histological examination based on the criteria established by Oboshi and Shimosato showed radiation effects better than grade II b in 32.1% primary tumors and in 33.3% of metastatic lymph nodes within the radiation field. No significant differences in the incidence of side effects or complications were noted between the two groups.

Adult↗
PubMed1989

[Transcatheter arterial embolization in patients with renal arteriovenous malformation: a report of two cases].

We report two cases of renal arteriovenous malformation (AVM) with chief complaints of macroscopic hematuria, and treated with transcatheter arterial embolization (TAE) using Gelfoam. Although hematuria disappeared after TAE in both cases, recanalization of AVM was revealed by follow-up renal arteriography one and three months later respectively. TAE were repeatedly performed at the same time. At the follow-up, the partial infarction in the normal parenchyma of the treated kidney was demonstrated on CT scanning in one case. We suggest that if the residual or recanalization of AVM after the initial TAE is observed, careful follow-up should be preferred without repeated TAE unless some deriving symptoms have appeared.

Adult↗
PubMed1989

[Renal cell carcinoma associated with tuberous sclerosis: a case report].

Renal angiomyolipoma associated with tuberous sclerosis is well known. On the other hand, few cases of renal cell carcinoma in connection with tuberous sclerosis have been reported. We report a patient with tuberous sclerosis whose kidney was involved with renal cell carcinoma. A 18-year-old woman was first admitted in August 1987 for evaluation of left renal tumor. Diagnosis of tuberous sclerosis was made when she was 11 years old on the basis of mental retardation, papules on her face, seizures, white leaf-shaped macules and periventricular calcifications. Computerized tomographic scan demonstrated a large mass arising from the left kidney and small masses in the right kidney. Angiography confirmed bilateral hypervascular renal tumors. On these bases, a clinical diagnosis of bilateral renal angiomyolipomas was made and surgical treatment of the left kidney was recommended because of its large size. However, her parents did not permit treatment until March, 1988. Finally, left nephrectomy of 4,750 g was performed and histological examination revealed renal cell carcinoma with clusters of spindle cells. In the literature available to us, we found twelve reports of malignant renal tumors associated with tuberous sclerosis including five renal cell carcinomas in Japan.

Adolescent↗
PubMed1989

[Clinical studies on urinary tissue polypeptide antigen (TPA): problems and improvement in determination].

The reliability of measurement of urinary TPA using a Prolifigen TPA kit (Sangtec, Sweden) was investigated, and an improved method for stabilizing TPA was tested. Samples were filtrated with a cellulose nitrate membrane filter to remove impurities as a possible cause of a high false positive rate which has been a problem in urinary TPA measurement. Serum TPA and Tween 40-treated urinary TPA was not adsorbed by the filter, whereas TPA in the non-treated urine showed a marked affinity to the filter. This shows the instability of TPA in the original urine, and the impropriety of filtration as a measure of purification of urine samples. The dilution test of urine and the standard TPA, and the recovery test of the standard TPA added to 6 different urine samples showed reasonable results only when the samples were treated with Tween 40; otherwise the values were lower than expected. Thirty-four spot urine samples were tested to examine the change in TPA value during the storage for 24 hours. TPA values decreased when urine was stored at room temperature, but this change was prevented by treatment of urine with Tween 40.

Biomarkers, Tumor↗
PubMed1989

Experimental allergic encephalomyelitis. I. Oligodendroglial cell population in monkey brain at the acute stage.

Populations of oligodendroglial cells (ODC) visualized by the neuroglial impregnation technique were investigated in demyelinated (A), actively demyelinating (B) and non-demyelinating (C) zones in both the cerebral and cerebellar white matter of monkeys with active EAE lesions. A marked reduction of the ODC population (P less than 0.001) was recognized not only in zones A and B but also in zone C as compared with those of non-sensitized monkeys. This suggests that the injury seen in ODC precedes myelin sheath destruction.

Acute Disease↗
PubMed1988

Occurrence of uroepithelial tumors of the upper urinary tract after the initial diagnosis of bladder cancer.

We treated 519 patients with primary bladder cancer, of whom 12 had upper urothelial tumor during followup. Almost all patients had superficial bladder cancer at diagnosis. All but 1 of 12 patients who underwent total cystectomy with ileal conduit diversion also underwent various transurethral procedures for treatment of the primary bladder lesions. The over-all incidence of bladder cancer patients who subsequently had upper urinary tract tumors was 2.3 per cent. Among the patients with treated bladder tumors a higher incidence (13.2 per cent) was observed in dye workers than in the general population (1.1 per cent). The interval between initial treatment of the bladder cancer and diagnosis of the upper urinary tract tumor ranged from 7 to 170 months (mean 70 months). The frequency of upper urinary tract tumors increased with time. We conclude that the appearance of upper urinary tract tumor after diagnosis of primary bladder cancer may be promoted by nonspecific irritation of the urothelium, which previously was made unstable by urinary chemical carcinogens.

Aged↗