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M Ishigooka

Publications and source records attributed to M Ishigooka.

15 recordsLinked to original sources
PubMed1992

Role of Glu318 at the putative distal site in the catalytic function of cytochrome P450d.

Most microsomal P450s have a conserved "threonine cluster" composed of three Thrs (Thr319, Thr321, Thr322 for P450d) at a putative distal site. An ionic amino acid at 318 is also well conserved as Glu or Asp for most P450s. To understand the role of these conserved polar amino acids at the putative distal site in the catalytic function of microsomal P450, we studied how mutations at this site of P450d influence the activation of molecular oxygen in the reconstituted system. Catalytic activity (0.02 min-1) toward 7-ethoxycoumarin of the Glu318Ala mutant of P450d was just 6% of that (0.33 min-1) of the wild type, while those of Glu318Asp, Thr319Ala, and Thr322Ala were comparable to or even higher than that of the wild type. Consumption rates of O2 and formation rates of H2O2 of those mutants varied in accord with the catalytic activities. Especially, the efficiency (0.5%) of incorporated oxygen atom to the substrate versus produced H2O2 for the Glu318Ala mutant was much lower than that (3.7%) of the wild type, while that (58.8%) for the mutant Glu318Asp was 16-fold higher than that of the wild type. In addition, the autoxidation [Fe(II)---- Fe(III)] rate (0.074 s-1) of the Glu318Ala mutant was much lower than those (0.374-0.803 s-1) of the wild type and other mutants. Thus, we strongly suggest that Glu318 plays an important role in the catalytic function toward 7-ethoxycoumarin of microsomal P450d.

Amino Acid Sequence↗
PubMed1992

Role of Glu318 and Thr319 in the catalytic function of cytochrome P450d (P4501A2): effects of mutations on the methanol hydroxylation.

Polar amino acids in the (putative) distal site are well conserved in P450s. For example, Glu318 for P450d is well conserved as either Glu or Asp for P450s, and Thr319 for P450d is also conserved for P450s. We have studied how mutations at Glu318 and Thr319 of P450d influence the catalytic activity toward methanol associated with the activation of O2. Catalytic activities of Glu318Asp, Glu318Ala, and Thr319Ala mutants toward methanol were 60, 25, and 38%, respectively, compared with that of the wild type. O2 consumption and NADPH oxidation rates of each mutants varied corresponding to the catalytic activities. However, surprisingly, efficiency (16-40%) of incorporated O to the substrate vs. consumed O2 for the Glu318Ala and Thr319Ala mutants were higher than that (9%) of the wild type. In addition, H2O2, which is produced from uncoupling for the wild-type P450d, was not observed for reaction of the Glu318Ala and Thr319Ala mutants. It seemed that consumed O2 was partially reduced to 2 mol of H2O by 4-electron transfer from NADPH for the wild-type and Thr319Ala mutant. However, for the two Glu318 mutants, it appeared that the consumed O2 was not reduced in the same way. It was thus suggested that the conserved Glu318 and Thr319 of P450d are not essential for the activation of O2 in the methanol oxidation. Role of the water molecule or the methanol molecule in the catalytic function was implied.

Amino Acid Sequence↗
PubMed1992

Electrical stimulation of pelvic floor musculature by percutaneous implantable electrodes: a case report.

A forty-year-old man with reflex urinary incontinence due to spinal cord injury was treated with electrical stimulation of the pelvic floor musculature. In this case we employed percutaneous implantable electrodes and an external pulse regulator. After 4 weeks of stimulation incontinence was improved and urodynamically maximum cystometric capacity increased from 220 ml to 350 ml. Our method is easy and not invasive. This technique can be an alternative for the electrical stimulation for urinary incontinence.

Adult↗
PubMed1992

Terodiline in the treatment of nocturnal enuresis in children.

The effect of terodiline was investigated in 17 children with nocturnal enuresis. Twelve of them were evaluated urodynamically before treatment and 6 of these were proved to have detrusor instability with or without provocation. Terodiline in a daily dose of 12.5 mg was administered for 4 weeks. After treatment the number of wet nights per week has significantly decreased. Urodynamically, maximum cystometric capacity has statistically increased and in 2 patients involuntary contraction has disappeared. During these periods no serious side effects were encountered. Terodiline could improve urodynamic parameters in nocturnal enuresis. These changes appear to be favourable in clinical improvement.

Butylamines↗
PubMed1992

Serum prostatic acid phosphatase, gamma-seminoprotein and prostatic specific antigen in hemodialysis patients.

Serum concentrations of prostatic acid phosphatase (PAP), gamma-seminoprotein (gamma-Sm) and prostatic specific antigen (PSA) were measured in 31 hemodialysis patients without clinical signs of malignant disease. PAP, gamma-Sm and PSA levels in serum were not significantly different between control and hemodialysis groups. A significant reduction in these tumor markers was not found after dialysis treatment. This indicates that the measurement of PAP, gamma-Sm and PSA in serum is useful for the detection of prostatic cancer in patients undergoing hemodialysis.

Acid Phosphatase↗
PubMed1992

Human penile hemodynamics by Xenon-133 clearance method in physiological erection.

We measured penile blood flow during physiological erection using the Xenon-133 clearance method in order to diagnose the exact cause of impotence. In 16 patients, in whom complete erection was obtained after visual sexual stimulation, the mean penile blood flow during erection was apparently higher than that in the flaccid state. On the contrary, in 6 patients whose reaction to visual stimulation was poor, penile blood flow did not change before and after stimulation. We considered that increased arterial flow was indispensable, but complete venous outlet obstruction was not necessary to produce a rigid erection. In addition, in the flaccid state the mean penile blood flow in the poor response group was apparently higher than that in the response group. This means that some patients who fail to obtain sufficient erection after visual sexual stimulation have increased venous outflow from the corpus cavernosum in the flaccid state. Based on these findings, the main cause of erectile dysfunction in such cases is probably attributed to disorders of the venous outlet system in the cavernous body.

Adult↗
PubMed1991

Absorption spectral study of cytochrome P450d-phenyl isocyanide complexes: effects of mutations at the putative distal site on the conformational stability.

Interactions of phenyl isocyanide (PheNC) with purified engineered cytochrome P450d wild type and putative distal mutants, Glu318Asp and Glu318Ala, were studied with optical absorption spectra. The wild type and the mutant Glu318Asp were purified as the high-spin state, while the mutant Glu318Ala was purified as the oxygen-bound low-spin form. Thus, it is suggested that Glu318 is important to make the appropriate heme environment of P450d. Spectral dissociation constants (0.19-0.39 mM) of the ligand for the ferric mutants were lower than that (0.74 mM) of the wild type. These dissociation constants were changed by adding a substrate, 7-ethoxycoumarin. The reduced wild type-PheNC complex showed a Soret peak at 451 nm, while the reduced mutant-PheNC complexes showed two peaks at 451 and 423 nm. The 451-nm peak of the complexes decreased with the concomitant increase of a new peak at 433 nm at room temperature. Thus, it was suggested that P450d can take two conformationally different forms from the characteristic spectral features. The Soret spectral conversions which followed the first-order kinetics were analyzed by changing the temperature. The activation energy (69 kcal/mol) for the conversion for the wild type was higher than those (37-50 kcal/mol) for the mutants. The activation energy for the wild type further increased (by 55%) by adding the substrate, while those for the mutants were essentially unchanged by adding the substrate. We discuss the important role of Glu318 at the putative distal site of P450d in the packing or the conformational stability of the putative distal site of the P450d molecule.

Amino Acid Sequence↗
PubMed1991

Successful repair of huge bladder diverticulum with a transurethral fulguration. Report of a case.

We present a 68-year-old man with a huge bladder diverticulum associated with benign prostate hypertrophy treated with transurethral fulguration of the diverticular mucosa in combination with transurethral resection of the prostate. The procedure was well tolerated by the patient and unfavorable symptoms faded after this procedure. Follow-up cystogram demonstrated remarkable reduction of the diverticulum.

Aged↗
PubMed1991

Intracavernous injection of prostaglandin E1: the application to cavernosography and penile blood flow measurement for the diagnosis of venogenic impotence.

We injected 20 micrograms of prostaglandin E1 (PGE1) intracavernously in 32 patients with impotence, we then examined penile blood flow using a Xe-133 washout technique. In addition, we also performed a cavernosography. After PGE1 injection, 18 patients (56%) showed complete erection, 10 (31%) tumescence, and 4 (13%) no response. Fourteen patients who presented either an inadequate or no response to PGE1 injection were suspected to have vasculogenic impotence. Cavernosography of patients who showed good response after PGE1 injection demonstrated no obvious venous leakage. In this group penile blood flow decreased after full erection. However, 7 patients (50%) suspected to have vascular problems showed venous leakage. Subsequently, these 7 patients appeared to be cases of venous incompetence. The penile blood flow of these 7 patients before or after PGE1 injection was not statistically different from that of other groups. Based on these findings, cavernosography after PGE1 injection appears to be useful for differentiating the venous factor of impotence.

Adult↗
PubMed1991

[Silicate urolithiasis: a case report].

A 62-year-old male visited our department complaining of left flank pain and urinary retention on November 6, 1989. Intravenous pyelography showed small stone shadows in bilateral ureters and lower calyx of kidney and the left kidney was not visualized. Endoscopically, calculi were seen in bilateral ureteral orifice. An ureteral catheter could not be passed up from there bilaterally. On November 13, 1989, January 24 and 26, 1990, calculi were passed out spontaneously. Analysis of the stones revealed silica calculus. The patient had a past history of duodenal ulcers. He was administered magnesium silicate and magnesium alminometasilicate as an anti-acid drug for ten years. Sixteen cases of silica calculus in Japan are reviewed.

Cystoscopy↗
PubMed1991

[Ureteral endometriosis: a case report].

A 32-year-old female visited our clinic with the chief complaints of macroscopic hematuria and pollakisuria in February 18, 1987. Cystoscopic examination revealed findings of cystitis but bleeding from the ureteral orifice was not observed. IVP showed right non visualized kidney and retrograde pyelography demonstrated right ureteral stenosis on the lower ureter and right hydronephrosis. Total hysterectomy, right oophorectomy and right ureterolysis were carried out in March 5. Right lower ureter was buried in the fibrous tissue approximately over 2 cm above the crossing with iliac vessels. Dark reddish colored small tumor was noticed in the stenosed ureter and resected. The histological diagnosis confirmed endometriosis. A total of 37 cases of ureteral endometriosis in the Japanese literature was reviewed.

Adult↗
PubMed1991

[Localized amyloidosis of the ureter: a case report].

A 58-year-old woman was introduced to our department complaining of lower abdominal pain and macrohematuria in March, 1978. Intravenous pyelography revealed stenosis and a ureteral stone on the right distal ureter. In May, 1983, she visited our department again. Endoscopically, bleeding from the right ureteral orifice was observed. Retrograde pyelography demonstrated the right hydronephrosis and irregular margin of the right lower ureter. However, the urine cytology was negative, and CT scan and ureteroscopy showed no tumorous lesion on the portion. On 7 August, 1989, partial ureterectomy and end to end anastomosis was performed. Histopathological examination by H-E and Congo red stain proved amyloid deposition. Postoperative course was uneventful. A total of 40 cases of amyloidosis of the ureter in the world are reviewed.

Amyloidosis↗
PubMed1990

[Intracavernous indurations after injuries to the external genital parts caused by a motorcycle tank].

We have experienced 2 cases of intracavernous induration after injuries to the external genital parts caused by a motorcycle tank. Case 1. A 28-year-old male was admitted to our department complaining of painless indurations of the penile radix. Cavernosography showed segmental filling defect in left corpus cavernosum. Because erectile disturbance was noted, resection of the induration was carried out. Microscopic section of the excised tissue showed only fibrosis. Case 2. A 20-year-old male visited our clinic with chief complaints of induration of the penile radix and erectile disturbance. Corpus cavernosography demonstrated filling defect in bilateral corpus cavernosum. We recommended the resection of the indurations, but the patient refused. A brief review on etiology and therapy of intracavernous fibrosis was made.

Accidents, Traffic↗