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Y Shiraiwa

Publications and source records attributed to Y Shiraiwa.

At least 19 recordsLinked to original sources
PubMed1992

Prototype of a reflux-preventing ureteral stent and its clinical use.

We have experimentally produced a ureteral stent which prevents vesicorenal reflux. This stent has a thin silicon sleeve at its distal end (intravesical portion). In a model experiment the sleeve demonstrated an excellent capability to prevent reflux. The sleeve allowed flow of fluid with minimal pressure rise. A patient with bilateral ureteral obstruction was managed with endoscopic insertion of a sleeved stent in the right ureter and a usual pigtail stent in left ureter. During cystography vesicorenal reflux was not observed on the right side while reflux occurred on the left side. Excretory urography forty days after stent placement demonstrated recovery of renal function and maintenance of drainage in both renal units. Thus, the drainage characteristic of this stent appears to be approximately the same as that of usual stent.

Drainage↗
PubMed1992

[Clinical results of prophylactic intravesical chemotherapy on superficial bladder cancer using the dye exclusion assay].

A chemosensitivity test was carried out on superficial bladder cancer using the dye exclusion assay for the purpose of screening chemosensitive drugs for prophylactic intravesical chemotherapy. Bladder cancer cells of each patients were incubated, in vitro, in the presence of adriamycin, (2"R)-4'-0-tetrahydropyranyladriamycin, mitomycin C, pepleomycin and 4'-epi-adriamycin (500 micrograms/ml) at 5%, CO2, 37 degrees C for 2 hours. The cytotoxic effect of the drugs was evaluated by the ratio of stained cells by trypan-blue. The most effective drug was instilled postoperatively into the bladder 3 times for the first week, and every 2 weeks during the following 14 weeks. In 18 patients followed more than 4 months the prophylactic effect was evaluated. Fifteen of the 18 patients completed the protocol, but the remaining 3 patients failed to complete to the instillation because of severe irritability of the bladder. Tumor recurrence was demonstrated in two patients. Non-recurrence rates of tumors at 12 and 24 months were 93.8% and 82.0%, respectively. These results suggested that this rapid and handy assay was useful for the purpose of screening chemosensitive drugs for the intravesical chemotherapy.

Administration, Intravesical↗
PubMed1992

Recording the bladder electromyogram for bladder activity evaluation during post-operative urinary urgency.

When the intravesical pressure cannot be measured because of continuous drainage, bladder electromyography is an alternative means of evaluating the functional condition of the urinary bladder. However, many problems that accompany this procedure have not been solved. In the present study we tried bladder electromyography with a newly-developed carbon fiber electrode in a patient who underwent an open prostatectomy. It was helpful in recognizing the relationship between urinary urgency and the spasmic activity of the vesicular detrusor muscle.

Aged↗
PubMed1992

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from urinary tract infections (1988). I. Susceptibility distribution].

Isolation frequencies and sensitivities to antibacterial and antibiotic agents were investigated on 801 bacterial strains isolated from patients with urinary tract infections in 9 hospitals during the period of June to November 1988. Of the above total bacterial population, Gram-positive bacteria accounted for 29.3% and a majority of them were Enterococcus spp. Gram-negative bacteria accounted for 70.7% and most of them were Escherichia coli. 1. Enterococcus faecalis: Vancomycin was most active with its MIC90 < or = 0.78 microgram/ml. Ampicillin, piperacillin, ofloxacin (OFLX), ciprofloxacin (CPFX) and imipenem (IPM) were also active. 2. Staphylococcus aureus: Arbekacin and minocycline were most active with their MIC90s 0.39 microgram/ml and 1.56 micrograms/ml, respectively. Among penicillins, dicloxacillin was the most active. Activities of cephems were considerably lower. 3. E. coli: Most of the agents were tested active. Particularly the second and third generation cephems were active in a range of < or = 0.10-0.20 microgram/ml. Carumonam (CRMN), IPM, OFLX and CPFX were also active with MIC90s < or = 0.10 microgram/ml. 4. Klebsiella pneumoniae CRMN and IPM were highly active. Penicillins generally showed lower activities. Cephems and new quinolones had high activities with their MIC90s in a range of 0.39-0.78 microgram/ml. 5. Proteus mirabilis: The third generation cephems were active with their MIC90s in a range of < or = 0.10-0.20 microgram/ml. CRMN, OFLX and CPFX were also active with their MIC90s < or = 0.10 microgram/ml, 0.39 microgram/ml and 0.20 microgram/ml, respectively. 6. Pseudomonas aeruginosa: IPM and tobramycin were active with their MIC90s 1.56 micrograms/ml and 3.13 micrograms/ml, respectively. CRMN and new quinolones showed MIC80s of 25-100 micrograms/ml. Most of penicillins and cephems were not active. 7. Other Gram-negative rods: Against Citrobacter freundii, Enterobacter cloacae and Serratia marcescens, IPM, CPFX and OFLX were active. Penicillins and cephems were not so active. CRMN was active against S. marcescens with its MIC80 at 6.25 micrograms/ml.

Anti-Bacterial Agents↗
PubMed1992

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from urinary tract infections (1988). II. Background of patients].

Clinical background was investigated on 916 bacterial strains isolated from patients with urinary tract infections (UTIs) in 9 hospitals during the period from June to November, 1988. 1. Distribution of sexes, ages and infections: Among males, fifties and older were most frequent and most of them had complicated UTIs. Among females, most cases among twenties or thirties were uncomplicated UTIs. Forties and older cases were most frequent and complicated UTIs were more frequent among them than among patients in twenties and thirties. 2. Distribution of sexes, ages and pathogens isolated from UTIs: In males, Pseudomonas spp. and Enterococcus spp. were frequently isolated. In contrast, in females, Escherichia coli was the most frequent. In thirties, E. coli was not the most frequently isolated bacterium. Frequency of Pseudomonas spp., other non-fermented Gram-negative rods and Enterococcus spp. were greater among patients with higher ages. 3. Administration of antibiotics and pathogens isolated from UTIs: (1) Before administration: In uncomplicated UTIs, E. coli accounted for the majority of causative organisms. In complicated UTIs, particularly in those cases with indwelling catheter, Enterococcus spp. and Pseudomonas spp. were rather frequently isolated. (2) After administration: In complicated UTIs, higher number of pathogens were isolated. Pseudomonas spp. and Enterococcus spp. were the most frequent. Distribution of pathogens isolated from complicated UTIs without indwelling catheter was similar to that before antibiotic administration.

Adult↗
PubMed1992

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from urinary tract infections (1988). III. Secular changes in susceptibility].

Sensitivities to various antibacterial and antibiotic agents of strains of Escherichia coli, Klebsiella spp., Proteus spp., Citrobacter spp., Enterobacter spp., Serratia marcescens and Pseudomonas aeruginosa isolated from patients with urinary tract infections (UTIs) in 9 hospitals during June to November 1988 were compared with those in the same period of previous year according to a classification, uncomplicated UTIs, complicated UTIs without indwelling catheter, and complicated UTIs with indwelling catheter. No remarkable changes were found in sensitivities of E. coli, Proteus spp., Citrobacter spp. and S. marcescens. The sensitivity of Klebsiella spp. to cephems decreased in complicated UTI without indwelling catheter and increased in complicated UTI with indwelling catheter. The sensitivity of Enterobacter spp. to third generation cephems decreased in complicated UTI with indwelling catheter. Sensitivities of P. aeruginosa to aspoxicillin and cefsulodin increased. The number of resistant strains to new quinolones increased slightly.

Anti-Bacterial Agents↗
PubMed1992

[Postoperative intravesical instillation of THP for superficial bladder tumor: clinical results of prophylactic effects on the recurrence. Fukushima THP Research Group].

Intravesical instillation of pirarubicin (THP) was performed on 66 patients with superficial bladder cancer after transurethral resection to evaluate the prophylactic effect against tumor recurrence. Intravesical chemotherapy was carried out at the concentration of 20mg/40ml. THP was initially instilled three times for one week, following instillation of every two weeks for ten times, and then every one month for seven times. Bladder irritability was demonstrated 21 of 66 cases (31.8%). Although there was a case of contracted bladder, generalized side effect was no case. Eligible cases for evaluation of efficacy were 43 out of 66 patients. The non-recurrence rate (by Kaplan-Meier's method) at one and two years were 90.4% and 77.8%, respectively. Intravesical THP instillation seems to be effective for the purpose of prophylaxis against the recurrence of superficial bladder tumor.

Administration, Intravesical↗
PubMed1992

[Visualization of the intravesical urine stream].

Although many urodynamic techniques have been used to evaluate the function of the lower urinary tract, the principles of these measurements are only based on a relationship between flow rate and pressure. In addition to these measurements, the intravesical urine stream would provide useful information on urodynamics. We have experimentally attempted to visualize the urine stream in a bladder using transrectal ultrasound examination. Since an air-particle is a good target for ultrasound visualization, we instillated a 10% glycerine solution into the bladder for the maintenance of air-particles. Before instillation, this glycerine solution was strongly shaken so that air-particles were kept in the solution. The urine stream was successfully observed throughout the whole process of voiding. In video-recording analysis, the velocity of urine stream was measured by tracing some air-particles. The velocity of urine stream was approximately 28.4 cm/sec in the body and increased to 116.6 cm/sec at the bladder neck. Thus, the urine stream was accelerated toward the urethra during voiding. Therefore, it seems that visualization of the urine stream offers a new parameter for evaluation of urodynamic studies.

Humans↗
PubMed1991

Cefminox sodium penetration into prostatic tissue with and without inflammation.

The concentrations of cefminox sodium (CMNX) in serum and prostatic tissue were determined in 36 cases of prostatic hyperplasia with and without inflammation. Mean ratios of CMNX in tissue over concentration in serum were 0.11 +/- 0.07 for patients with inflammation and 0.09 +/- 0.06 for those without inflammation. There was no significant difference between the two groups. These data suggest that CMNX penetration into prostatic tissue is not influenced by the presence of inflammation.

Aged↗
PubMed1991

[Cytologic atypical grade of exfoliative cytology versus histologic differentiation degree in prostatic carcinoma].

Our method of exfoliative cytology using a prostatic fluid collecting catheter is effective in detecting prostatic carcinoma. To presume histological diagnosis by means of the cytology we analyzed cytological findings of 62 cases of prostatic carcinoma in relation with their biopsy findings, clinical stages and clinical courses. In cases in which cellular atypism was low in the cytology the carcinoma was mostly well or moderately differentiated. Conversely, in cases in which the carcinoma was well differentiated atypism was mostly low in the cytology. In cases in which the cellular atypism was high the carcinoma was poorly differentiated, and vice versa. The poorer histological differentiation and the higher cytological atypism, the more advanced carcinoma and the higher death rate from the carcinoma. The tendency seemed to be more related with the cellular atypism than with the histological differentiation. Thus the cytological findings reflect the histology well and the degree of the histological differentiation can be presumed by the cytological atypism. The cellular atypism is not a less important factor than the histologic differentiation degree for determining the clinical stage and the prognosis.

Adenocarcinoma↗
PubMed1991

[Chemosensitivity test on superficial urinary bladder cancer using the dye exclusion assay--model of intravesical chemotherapy].

A chemosensitivity test was carried out on superficial bladder cancers using the trypan blue dye exclusion assay for the purpose of screening chemosensitive drugs for intravesical chemotherapy. Transplantable murine bladder tumor cells (MBT-2) were incubated, in vitro, in the presence of adriamycin (4, 40, 400, 1000 micrograms/ml) as well as verapamil (3, 30, 100, 500 micrograms/ml) at 5% CO2, 37 degrees C for two hours. After cellular viabilities were calculated, MBT-2 cells were inoculated into the hind limbs of mice. The cellular viability was correlated well with the ratio of tumor appearance, tumor growth inhibition and prolongation of survival, and was dose dependent in the adriamycin treated groups. On the other hand, a reduction of cellular viability, tumor growth inhibition and prolongation of survival were seen in the high dose verapamil (100, 500 micrograms/ml) treated groups. Human superficial bladder cancer cells were incubated in the presence of adriamycin, 4'-0-tetrahydropyranyladriamycin, mitomycin C and pepleomycin (1000 micrograms/ml) and/or verapamil (500 micrograms/ml). The reduction rates of cellular viability markedly varied with the kind of anticancer drugs. A reduction of cellular viability of human tumor cells as well as MBT-2 cells was seen in the verapamil treated groups. This rapid and handy assay seems to be useful for the purpose of screening chemosensitive drugs for intravesical chemotherapy.

Administration, Intravesical↗
PubMed1991

[Effect of KT-611 (Naftopidil) on the contraction of human prostatic tissue and its use in benign prostatic obstruction].

A new alpha 1-adrenergic receptor antagonist, KT-611 (naftopidil) antagonized dose dependently the contraction induced by agonists, noradrenaline and phenylephrine in the human prostatic tissue. KT-611 at a dosage of once or twice a day was evaluated for its effects on 49 patients with benign prostatic hypertrophy. The drug improved subjective and objective symptoms significantly. The residual urine was reduced in volume and percentage significantly. The average and maximum flow rates increased significantly. The optimal dosage was presumed to be in the range of 25 to 75 mg once a day or 25 to 100 mg twice a day. Adverse reactions and abnormal laboratory findings were all slight. KT-611 was concluded to be useful in the treatment of patients with benign prostatic hypertrophy.

Adrenergic alpha-Antagonists↗