Biomedical subjects

S Tokunaka

Publications and source records attributed to S Tokunaka.

At least 19 recordsLinked to original sources

PubMed1995

[Effects of chronic low-frequency electrical stimulation on the external urethral sphincter of male rabbits--electrophoretic analyses of myosin light and heavy chain isoforms].

The present study investigates the effects of chronic low-frequency electrical stimulation on the external urethral sphincter (EUS) of rabbits through the biochemical analysis of the isoforms of myosin light and heavy chains. Twenty-eight adult male rabbits were used in the test. Of these, the EUS of 14 rabbits were continuously stimulated directly at 1.8 Hz, 0.8 msec, 5.0 V with an implantable electrical cardiac pacemaker for more than 10 weeks. The other 14 rabbits were used as the control group and were nurtured under the same conditions as the stimulated group but without the electrical stimulation. Upon conclusion of the stimulation program, the urethra was removed from all 28 rabbits. The portion of the urethra containing the EUS (from the middle of the prostate to the pelvic diaphragm) was cut transversely into thin serial sections and glycerinated. The glycerinated muscle fibers were then isolated under a stereomicroscope and samples for electrophoretic analysis were prepared. Two-dimensional electrophoresis according to the procedure of O'Farrell for myosin light chains and SDS-PAGE containing 40% glycerol for myosin heavy chains were carried out. The molar ratio of myosin subunits was determined by quantification through the dye elution process. The average percentages of slow myosin light chain molecules in 8 unstimulated and 8 stimulated EUS were 33.4 +/- 8.9% (mean +/- SD) and 70.1 +/- 12.8%, respectively. The average percentages of slow myosin heavy chain molecules in 6 unstimulated and 6 stimulated EUS were 17.6 +/- 5.7% and 40.2 +/- 7.1%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1994

[Biochemical analysis of the external striated urethral sphincter of male rabbits. Difference in the proportions of muscle fiber types in the male rabbit external urethral sphincter by axial subdivisional study].

We studied the difference in the proportion of fast and slow myosin subunits in axially subdivided external urethral sphincter of male rabbit using myosin light chain and heavy chain analyses. The whole urethras from 6 adult male Japanese White rabbits were sagittally bisected and one halves from all animals were processed for myosin light chain analysis and another halves from all animals for myosin heavy chain analysis. Each half urethra containing the external urethral sphincter was subdivided into 4 parts, namely prostatic (P), prostatic apical (PA), infraprostatic (IP) and bullbourethral glandular (BUG) portions, from cranial to caudal direction. The electrophoretic samples from 4 different parts were separately processed. The external urethral sphincter muscle in each part from all animals were processed together for a sample because of the minute amount of the muscle. Two-dimensional electrophoresis according to the procedure of O'Farrell for myosin light chains and SDS-polyacrylamide gel electrophoresis containing 40% glycerol for myosin heavy chains were carried out. Molar ratio of myosin subunits were estimated by the dye elution procedure. The relative proportions of slow myosin molecules in respective parts were 33.4% (P), 26.3% (PA), 18.5% (IP) and 11.0% (BUG) from myosin light chain analysis and 20.3% (P), 16.1% (PA), 7.2% (IP) and 5.0% (BUG) from myosin heavy chain analysis. The urethral striated musculature in male rabbit was predominantly composed of fast myosin subunits as a whole. But the proportion of slow myosin subunits occupied a relatively high percentage in the proximal region and tended to decrease toward the distal end.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1993

Proportions of fiber types in the external urethral sphincter of young nulliparous and old multiparous rabbits.

The proportions of fast and slow myosin molecules in specimen's of the external urethral sphincter (EUS) from 6 young nulliparous (6-month-old) and 6 old multiparous (2-year-old) rabbits were studied using myosin heavy chain electrophoresis. The percentages of fast and slow myosin molecules were 80.4 +/- 4.5% and 19.6 +/- 4.5% in the EUS from nulliparas, and 68.7 +/- 6.3% and 31.3 +/- 6.3% in the EUS from multiparas. The difference between the two groups was significant (P < 0.01). We suggest that a selective decrease in the volume of type 2 (fast) muscle fibers and/or conversion of type 2 to type 1 (slow) muscle fibers had taken place in the EUS of old multiparas. The proportional change in the constituent muscle fibers of the EUS with aging may play a role in human genuine stress incontinence.

Aging↗

PubMed1993

Secondary mucinous adenocarcinoma of the prostate in a patient with ulcerative colitis.

Herein we report a rare case of prostatic invasion of rectal carcinoma in a patient with ulcerative colitis. Malignant transformation is a well-known complication of long-standing ulcerative colitis. Mucinous adenocarcinoma, with positive carcinoembryonic antigen and negative prostate-specific antigen, strongly suggested the rectal origin of the tumor.

Adenocarcinoma, Mucinous↗

PubMed1993

[Pelvic fibromatosis simulating urachal tumor--a case report].

We report a case of pelvic fibromatosis, which has been rarely found. A 36-year-old man referred to our hospital complaining of right abdominal pain and a swelling mass. Abdominal CT and transabdominal echogram revealed a tumor contacted to the bladder. A nonpapillary tumor (little finger sized) at the bladder dome was observed by cystoscopy, and the tumor was clinically considered as urachal tumor. Wide radical excision including the bladder and prostate was performed. Pathological diagnosis was pelvic fibromatosis arising from musculoaponeurotic structures in the pelvis: The fibromatosis is benign nonmetastatic tumor but the recurrence rate is considerably high. However, in the present case, 14 months after operation there is no recurrence yet.

Abdomen↗

PubMed1993

[A case of malignant paraganglioma].

Herein we report a case of paraganglioma. The metastatic lesion was incidentally found in a 64-year-old man by chest roentgenography. The primary tumor was extra-adrenal and was revealed to be malignant. The patient was normotensive without clinical symptoms despite extreme high serum and urinary dopamine levels. A venous injection of 5 mg metoclopramide elicited a significant increase of the blood pressure. This phenomenon disappeared after surgical excisions of the primary and metastatic lesions. The metoclopramide test is considered to be useful to diagnose asymptomatic paraganglioma.

Humans↗

PubMed1993

[Dementia, daily activities and micturition of the elderly living in a nursing home].

This report shows the relation between daily activities, dementia and urinary disturbance. The subjects consisted of 44 males and 110 females with an average age of 80 years (ranged from 57 to 102). We evaluated the daily activities, underlying diseases, state of urination and the intelligence by the scale of Hasegawa. The persons with diapers had a higher degree of dementia than those who could go to the lavatory. As the degree of dementia aggravated, the incidence of urinary incontinence significantly increased. Urodynamic studies were performed on 49 persons who had urinary disturbance. There were 25 persons with normal vesical function, 16 with overactive vesical function, and 8 with underactive vesical function. Since all of the incontinent persons without dementia had abnormal vesical function, pharmacologic therapy was expected to be effective for them to improve incontinence. Half of the incontinent persons with dementia had normal vesical function. Mental and physical disabilities seemed to be the main factors causing incontinence in these persons. The multidisciplinary approach including medication, behavior treatment and awareness of the nursing staff is important and effective to reduce urinary incontinence.

Activities of Daily Living↗

PubMed1993

[Two cases of male infertility with pathological dilatation of ejaculatory duct].

Two cases of male infertility with pathological dilatation of ejaculatory duct are reported. In both cases, the dilatated wall of the ejaculatory duct was incised at the vermontanum with a cold knife endoscopically. After the incision, the findings of semen analysis of one case improved markedly and his wife became pregnant. In another case, semen analysis was not improved. Transurethral incision seemed to be a useful modality for the treatment of pathological dilatation of ejaculatory duct.

Adult↗

PubMed1992

Dimethylsulfoxide enhances the absorption of chemotherapeutic drug instilled into the bladder.

We examined the effect of dimethylsulfoxide (DMSO) on the absorption of a chemotherapeutic drug instilled into the bladder. Female Wistar rats with bladder tumors underwent intravesical instillation of normal saline (S group) or 50% DMSO (D group) prior to the administration of pirarubicin (tetrahydropyranyl-Adriamycin). The absorption of pirarubicin was estimated histologically by observing its fluorescence. In the S group, fluorescence of pirarubicin was observed only in the epithelial layer of normal or hyperplastic regions and in the cells of superficial layers of the tumor. In the D group fluorescence was observed in the entire bladder wall of normal or hyperplastic regions and extended to deeper regions of the tumors than in the S group. These findings indicate enhancement of the absorption of pirarubicin by pretreatment with DMSO.

Absorption↗

PubMed1992

[Biochemical analysis of the external urethral sphincter of female rabbits].

The proportion of fast and slow myosin molecules in external urethral sphincter (EUS) was studied. The contents of fast and slow myosin light chains in EUS from 6 female rabbits (Japanese White, 6-month-old) were estimated using two-dimensional electrophoresis. The percentages of fast and slow myosin molecules were 54.5 +/- 14.9 and 46.0 +/- 14.9, respectively. It was thus shown that female rabbits EUS is composed of both fast and slow muscle fibers. The ratio of fast to slow myosins in female EUS was different from that in male EUS (fast myosin 90%). These results implicate that female and male EUS would be functionally distinct.

Animals↗

PubMed1992

[A case of multilocular renal cell carcinoma].

Herein we report case of multilocular cyst of the right kidney complicated with clear cell type renal cell carcinoma. The chief complaint of the 51-year-old male patient was macroscopic hematuria. He underwent radical nephrectomy and was administered postoperative adjuvant chemotherapy with alpha-interferon. No recurrence was found 18 months after operation. Pathogenesis of multilocular cyst of the kidney and the mechanism of malignant transformation are discussed.

Carcinoma, Renal Cell↗

PubMed1991

Localization of small renal tumor by dynamic computerized tomography.

Herein we report on 4 cases of renal tumor whose diameter was less than 3 cm. A mass lesion was suggested by renal echography in mass screening program. Renal dynamic computerized tomography (CT) with bolus injection can delineate a mass lesion clearer than ordinary plain and enhanced CT, and renal angiography. In renal dynamic CT, tumor lesion is well depicted because of the difference between the time density curve in the tumor lesion and that in the surrounding renal parenchyma. Renal dynamic CT is considered to be an especially versatile modality to diagnose small tumors which are hardly delineated by ordinary enhanced CT.

Aged↗

PubMed1991

[Histochemical study of human external urethral sphincter].

Human external urethral sphincters (n = 13) were studied histochemically, using ATP-ase staining. The proportions of constituent muscle fiber types (slow twitch type 1 fibers: 35.6-97.7%, mean 65.7%, SD 16.6) were different among the individuals. There were no significant relationships between the percentage of type 1 fibers and the sex or the age. As for the mean muscle fiber diameter of 13 cases, the sizes of type 2 fibers (19.2-42.4 um, mean 27.8 um) were significantly (p less than 0.05, t-test) larger than those of type 1 fibers (15.7-30.3 um, mean 22.3 um). In analyses of individual cases, 10 male cases had significantly larger type 2 fibers than type 1. Two of 3 female cases had no significant difference in diameter between the two fiber types and the remaining 1 female case, in contrast with male cases, had significantly larger type 1 fibers than type 2. There was no significant relationship between the proportions and the diameters of constituent muscle fiber types. Our study thus showed extreme interindividual variation and implicated the presence of sexual difference in human external urethral sphincter muscle.

Adenosine Triphosphatases↗

PubMed1991

[Percutaneous management of benign ureteroileal anastomotic strictures after ileal conduit urinary diversion].

We report our experience with the endourological treatment of 4 patients with 5 benign ureteroileal anastomotic strictures after ileal conduit urinary diversion. The treatment was successful in 4 of the 5 renal units without restenosis with a mean follow up of 10 months. The strictures were dilated by ureteral dilators and/or balloon dilation catheters using guide wires through percutaneous nephrostomies in an antegrade fashion. A 9 or 12 Fr. percutaneous splint catheter or a 12 Fr. double pig tail catheter was placed for 3-8 weeks after a successful dilation. Two renal units underwent repeated dilations. In 1 renal unit, a guide wire was hardly passed through the stricture and the treatment was unsuccessful. No serious complications were encountered. Percutaneous endourological managements of ureteroileal anastomotic strictures seemed to be quite versatile techniques which should be tried as the initial approach in many cases.

Anastomosis, Surgical↗

PubMed1991

[A case of Menkes' kinky hair disease with a renal calculus and diverticula of the bladder].

Menkes' kinky hair disease is a poor prognostic congenital disease with X-linked recessive inheritance. This disease is clinically characterized by seizures, friable hair, growth failure, mental retardation and others. Recently it has been known that this disease is also characterized by multiple diverticula of the bladder and other urological abnormalities. A 6-year-old boy was diagnosed as having Menkes' kinky hair disease at another hospital several weeks after birth because of seizures, friable hair and low serum copper level. He voided by Credé's maneuver by the nurse because he could not void for himself. He was referred to our hospital for macrohematuria and micturition pain on October 8, 1989. Right renal staghorn calculus and multiple diverticula of the bladder were found by roentgenographic examination. He has been treated conservatively after discharge because of his poor condition.

Child↗

PubMed1990

The proportions of fiber types in human external urethral sphincter: electrophoretic analysis of myosin.

The proportions of fast and slow myosin molecules in external urethral sphincter specimens from ten urodynamically normal male bladder carcinoma patients were estimated from the contents of fast and slow myosin light chains in two-dimensional electrophoretic gels. The percentages of fast and slow myosin molecules ranged from 5.0% to 61.4% with a mean of 35.5% and from 38.6% to 95.0% with a mean of 65.5% respectively. It is therefore concluded that the human external urethral sphincter is composed of both fast and slow muscle fibers as well as other voluntary muscles. The human external urethral sphincter is considered to be a highly fatigue-resistant muscle with a very high proportion of slow muscle fibers. In the cases studied so far, there is a great diversity in the proportions of fast and slow myosin molecules; the reason for this remains unknown.

Electrophoresis, Gel, Two-Dimensional↗

PubMed1990

Leiomyoblastoma of the epididymis in a child.

A case of leiomyoblastoma of the epididymis in a 3-year-old boy is presented. Left high inguinal orchiectomy was performed. Light and electron microscopic examinations revealed a 3.5 X 2.3 X 1.5 cm. tumor continuous with the tail of the epididymis. The lesion proved to be a leiomyoblastoma of the epididymis. Leiomyoblastoma is a form of leiomyoma mainly composed of immature smooth muscle cells. The absence of keratin, epithelial membrane antigen and negative results by alcian blue stain indicated that there were no adenomatoid elements in the tumor.

Child, Preschool↗

PubMed1990

[The changes of population and distribution of S-phase cells in precancerous lesions of rat bladder revealed by the method of bromodeoxyuridine labeling].

We studied whether bromodeoxyuridine (BrdU)-labeling method showing the population and/or distribution of S-phase cells in tumor tissues is useful to detect the precancerous lesions of bladder. The bladder lesions were induced by 0.05% N-butyl-N (4-hydroxybutyl) nitrosamine (BBN) in drinking water for ten weeks in five male rats (Wistar-Imamichi). BrdU (50 mg/kg) was injected to intraperitoneal space two hours before the resection of the bladder. The detection of positive cells (S-phase cells taking BrdU) was performed by peroxidase-antiperoxidase method. From five bladder specimens 144 lesions (simple hyperplasia (S)-73, papillary or nodular hyperplasia (PN)-57, papilloma (Pa)-14) were analysed. The labeling index (the ratio of positive cells to all epithelial cells in one lesion) showed no significant difference among the lesions (S, PN, and Pa). For analyses of the distribution patterns of S-phase cells, we investigated whether positive cells aside from basal layers and/or the serial positive cells in basal layers were seen or not in each lesion. The ratios of lesions containing positive cells aside from basal layers were 11% (8/73), 60% (34/57) and 100% (14/14) in S, PN and Pa lesions. The serial positive cells in basal layers were observed in 6% (4/73), 25% (14/57) and 50% (7/14) of S, PN and Pa lesions. Those differences were statistically significant. Above mentioned results suggest that the appearance of S-phase cells aside from basal layers and/or the serial S-phase cells in basal layers is characteristic change in precancerous lesions, which is useful for sooner detection of bladder carcinogenesis.

Animals↗