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Biomedical subjects

W Sakamoto

Publications and source records attributed to W Sakamoto.

At least 73 records · Page 4Linked to original sources
PubMed1991

Linkage analysis of the nuclear homologues of mitochondrial plasmid-like DNAs in rice.

A genetical study on the nucleotide sequences of the nuclear DNAs which share homology with rice mitochondrial plasmid-like DNAs, B1, B2, B3 and B4 was carried out. Restriction fragments of the nuclear DNAs hybridized with these plasmid-like DNAs showed polymorphisms in their length between Indica and Japonica rice cultivars. The hybridized signals found specifically in Indica or Japonica cultivars segregated in the F2 population derived from a cross between these two subspecies. The observed ratio of the nuclear homologues in the F2 population demonstrated that they were transmitted according to the Mendelian inheritance. The co-segregation of homologues was examined and the linkage was detected between the B1-nuclear homologue of Japonica and the B4-nuclear homologue of Indica, and also between the nuclear homologues of B2 and B3 of Indica. The linkage between the B1-nuclear homologue of Japonica and the B4-nuclear homologue of Indica was conserved in the different rice cultivars.

Blotting, Southern↗
PubMed1991

[A case of renal pelvic squamous cell carcinoma accompanied with humoral hypercalcemia of malignancy].

A 74-year-old male was urgently admitted to our hospital because of consciousness disturbance. Laboratory data showed remarkable hypercalcemia (7.8 mEq/L), hypophosphatemia, low % TRP, low intact PTH level, normal nephrogenic cyclic AMP and normal 1,25 (OH)2D level. Serum bone Gla protein, which was thought to express osteoblastic activity, was low. Serum tartarate resistant acid phosphatase and urinary excretion of hydroxyproline, which were thought to express osteoclastic activity, were high. CT scan showed an enlarged mass in the left renal pelvis, which was found to be a squamous cell carcinoma (SCC) by biopsy through percutaneous nephroscopy. Bone scintigram appeared normal. Therefore, we diagnosed it as renal pelvic SCC with humoral hypercalcemia of malignancy (HHM) and performed left nephrectomy. After nephrectomy, serum calcium returned to normal. But after a few weeks, lung metastasis appeared and serum calcium was reelevated. As to PTH related protein (PTHrP) which was thought to induce HHM, PTHrP content of the resected tumor measured by RIA assay was 13 pmol/g wet weight of tissue, which suggested that this tumor might have been producing PTHrP.

Aged↗
PubMed1991

[Hyperthermic treatment in patients with benign prostatic hypertrophy].

Hyperthermic treatment was performed in 31 patients with benign prostatic hypertrophy (BPH). Eight patients of them had a urethral catheter because of urinary retention. The prostate was heated trans-rectally to 43-45 degrees C. The treatment consisted of 10 sessions of 60 min. each. To evaluate this treatment, the following parameters were determined before, during and one week after the last hyperthermia session: subjective symptoms score, and residual urine volume, uroflowmetry and transrectal ultrasound of the prostate as objective data. Symptoms score improve in all patients. Of 8 patients with a catheter, the catheter could be removed from 4 patients. There was no significant change in prostate volume, but significant decreases of residual urine volume, and increases of maximum flow rate and mean flow rate were observed. No adverse reactions were seen. Judging from the above results, this treatment is considered to be useful for patients with BPH.

Aged↗
PubMed1991

[Results of Kock pouch construction fully utilizing an auto-suture instrument].

From March 1987 to the end of February 1991, we performed Koch pouch construction as a urinary diversion on 20 patients who had undergone radical cystectomy due to bladder cancer. The operation was done according to the method of Skinner et al. We fully utilized an auto-suture instrument to ensure safe and stable suturing of the ileum and to shorten the operating time. It was of great concern that the staples placed at several portions might cause stone formation or aggravate infection. However, stone formation was observed only in one patient (5%) at the tip of a nipple valve in which a staple became the nucleus of the stone. Staples are usually not regarded as an obstacle as they are usually covered by the mucous membrane. In all patients, the maximum capacity of the pouch was more than 500 ml, intra-pouch pressure was kept low even when the pouch was inflated up to the maximum capacity, and reflux of urine into the upper urinary tract was not observed. As for complications, there was a slight degree of obstructive uropathy in 4 patients (20%), difficulty in catheter insertion was noted in 3 patients (15%), and stress incontinence-like urinary leakage was present in one patient when the capacity exceeded 500 ml. However, there were no complications which necessitated reoperation. In terms of blood chemistry, although there was a tendency towards a slight increase in BUN or hyperchloremia, no specific treatment was necessary as far as the kidney function was normal.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Inhibition of prostaglandin E2 and superoxide anion production in rat peritoneal macrophages by the calcium antagonists nifedipine and nisoldipine.

In order to clarify the possibility of an antiatherogenic action of the calcium antagonists nifedipine (CAS 21829-25-4) and nisoldipine (CAS 63675-72-9) the effect of nifedipine and nisoldipine on phorbol myristate acetate (PMA)- and calcium ionophore A23187-stimulated O2- and PGE2 production from macrophages was investigated. Nifedipine and nisoldipine inhibited dose-dependently PMA-stimulated O2- and PGE2 production, but not A23187-stimulated PGE2 production. The 50% inhibitory concentration (IC50) of nifedipine and nisoldipine for PMA-stimulated O2- production were 60 and 8 mumol/l, respectively, whereas those for A23187-stimulated O2- were 9.3 and 2.0 mumol/l. IC50 of nifedipine and nisoldipine for PMA-stimulated PGE2 production were 3.0 and 2.8 mumol/l, respectively. The release of [1-14C]-arachidonic acid from labeled macrophages stimulated with PMA was inhibited approximately by 39 to 43% in the presence of 20 mumol/l nifedipine and nisoldipine. The increase of (Ca2+)i in macrophages induced by A23187 could not be attenuated by nifedipine and nisoldipine, and (Ca2+)i level did not alter when stimulated with PMA. These results suggest that the inhibitory mechanism of nifedipine and nisoldipine for O2- production from the macrophages appears to directly inhibit the enzyme system of the NADPH-oxidase complex through the activation of protein kinase C, and that the inhibition of PMA-stimulated PGE2 production may be due to a decrease of phospholipase A2 through protein kinase C. On the basis of the inhibitory action on O2- and PGE2 production from the macrophages, a possible mechanism of antiatherogenic effect of calcium antagonists was discussed.

Animals↗
PubMed1991

[Extracorporeal shock wave lithotripsy for ureteral stones and cystine stones].

We report our experience with extracorporeal shock wave lithotripsy (ESWL) in the treatment of ureteral and cystine stones, which are known to be difficult to treat by this method. First, in order to determine the effectiveness of the ureteral catheter in the destruction of ureteral stones, we compared the clinical results of 121 patients treated without the catheter and 141 patients inserted with the catheter. There was no significant difference in the success rate between the two groups regardless of stone size, which indicates that the use of the ureteral catheter had no effect on the outcome of treatment. We then studied the clinical results of impacted ureteral stones which are especially difficult to destroy. Excretory urography was performed to non-invasively diagnose these stones, and those without visualization in the ureter below the stone were diagnosed as impacted stones and treated by ESWL without the ureteral catheter. Among the stones with a diameter of 1 to 2 cm, the success rate was significantly lower in impacted stones compared to non-impacted stone. These findings suggest that ESWL treatment without the ureteral catheter may be effective for ureteral stones with a diameter of less than 1 cm and non-impacted stones with a diameter of 1 to 2 cm, while combination therapy with other methods such as TUL may be better for other stones. We also performed ESWL on 6 patients with renal stones and 2 patients with ureteral stones which were cystine stones. Renal stones required an average 4.1 treatment with an average of 1,875 shocks per treatment, and ureteral stones required 1.5 treatment with an average of 1,833 shocks.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

[Effects of verapamil on cyclosporine. A (CsA)-induced nephropathy in ischemic kidney model in rats: changes in systemic hemodynamics and hepatic and renal microsomal cytochrome P-450].

We have examined the effect of verapamil on CsA-induced nephropathy by measurement of systemic hemodynamics including each organ blood flow using the microsphere method in ischemic kidney model of hemi-nephrectomized Wistar rats. Hepatic and renal microsomal cytochrome P-450 contents and their enzyme activities were measured to study the correlation between CsA-induced nephropathy and induction of hepatic and renal microsomal cytochrome P-450. All rats were hemi-nephrectomized (l-nephrectomy) and were classified into the following 6 groups: 1) control groups, 2) CsA at a dose of 40 mg/kg per day orally for 7 days (CsA group), 3) Oral administration of verapamil for 7 days in the CsA group (CsA + V group), 4) 20 min clamping of the remaining right kidney pedicle (Ischemic, Is group), 5) CsA was administered in the Is group (Is + CsA group), 6) Addition of verapamil to CsA in the Is + CsA group (Is + CsA + V group). Verapamil was given in the drinking water and the average dose calculated from the amount of drinking was 4.7 +/- 1.0 mg/kg per day and 5.2 +/- 0.7 mg/kg per day for the CsA + V group and the Is + CsA + V group, respectively. CsA caused significant increases in BUN and serum creatinine (sCr) with a significant decreases in renal inulin clearance (CIn) in all groups. When compared with the Is group, CsA caused significant decreases in cardiac output and all organ blood flow especially in renal blood flow with significant increases in BUN and sCr in the Is + CsA group.2+ degree of nephropathy.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

[Experience of extracorporeal shock-wave lithotripsy for the urolithiasis in horseshoe kidney].

At Osaka City University, 1,987 patients with urolithiasis have been treated by extra-corporeal shockwave lithotripsy (ESWL) during a four-year period. We treated 5 patients with horseshoe kidney and the obtained results were analyzed retrospectively. Three of these patients, who had a solitary stone could successfully be treated by ESWL as monotherapy. One who had multiple stones required transurethral lithotripsy after ESWL due to stone-street. The remaining 1 patient who had undergone heminephrectomy developed perirenal hematoma after ESWL, which spontaneously disappeared without any specific treatment. We discuss the special care related to the use of ESWL in the horseshoe kidney.

Adult↗
PubMed1990

[Instillation of a new anticancer preparation for the treatment of superficial bladder cancer: comparison of clinical efficacy between peplomycin emulsion in hydroxypropylcellulosum and peplomycin in saline solution on tumor reduction].

Clinical efficacy of a new preparation of peplomycin emulsion in hydroxypropylcellulosum (HPC-PEP) was studied in 26 patients to compared with that in 14 patients administered with 60 mg of PEP in 20 ml saline (S-PEP). The HPC-PEP was a mixture of 90 mg PEP suspended in 30 ml of 1% HPC. Both of preparations were retained in the bladder cavity over an hour after the instillation. Intravesical instillation was performed once for the patients with HPC-PEP, and 10 times repeatedly for the patients with S-PEP. A clinical evaluation was made on the basis of cytoscopic finding and cytology one week after the final instillation. According to the degree of tumor reduction, the results were classified into "disappearance", "greater than 50% reduction," and "no alteration or further growth" of primary tumor, which were referred respectively to "complete response (CR)", "partial response (PR)" and "not changed (NC)". The rates of CR and response were 27 and 73% respectively for the HPC-PEP administered patients, which were significantly higher than those of 8 and 43% respectively for the patients with S-PEP. In terms of configuration and number of tumor, intravesical HPC-PEP treatment was found to be superior to intravesical S-PEP treatment. In HPC-PEP treatment, a series of untoward symptoms such as bladder irritability and leukopenia was encountered at a frequency of 8%, which is much less than those seen in the S-PEP treatment. These clinical date suggest that HPC-PEP treatment against the superficial bladder tumors is superior to conventional S-PEP instillation in terms of administration frequency and potent doses available to tumor reduction.

Administration, Intravesical↗
PubMed1990

Effects of high energy shock wave exposure on renal function during extracorporeal shock wave lithotripsy for kidney stones.

In order to study the effects of high energy shock wave exposure on the kidney in extracorporeal shock wave lithotripsy (ESWL) using Dornier HM3, renal hemodynamics and renal function before and after ESWL were analyzed by 99mTc-DTPA renoscintigraphy. Various urinary enzyme activities (LDH, GOT, GPT, NAG, gamma-GTP) and low molecular protein concentrations (alpha 1-microglobulin, beta 2-microglobulin) before and after ESWL were also compared. In the early phase of the renoscinitgram obtained in the 1st min after injection of 99mTc-DTPA, the time required to reach maximum radioactivity was significantly prolonged after ESWL in both the affected and contralateral kidney. This indicated that renal blood flow decreased in both the affected and contralateral kidney immediately after ESWL. An analysis of the 30-min renoscintigram showed that urinary clearance was delayed in the affected kidney in spite of no overt obstruction due to stone fragments. As for urinary enzyme activities and low molecular protein concentrations, they were standardized by urinary creatinine concentration measured at the same time. Urinary LDH, GOT, GPT and NAG activities remarkably increased on the day of ESWL followed by a decrease close to pretreatment levels on the 4th day, though these levels were still significantly higher than pretreatment levels. Urinary gamma-GPT activity was significantly higher than the pretreatment level only on the day of ESWL. Urinary alpha 1-microglobulin and beta 2-microglobulin concentrations significantly increased on the day of ESWL and were still high on the 4th day.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetylglucosaminidase↗
PubMed1990

[A clinical study on urethral recurrence observed after cystectomy].

A clinical study was made on 108 male patients who underwent cystectomy. The posterior urethra and partial anterior urethra were removed in 47 cases, half of the perpendicular urethra was removed in 13 cases and the anterior urethra up to the fossa navicularis was removed in 48 cases. Out of 60 cases without urethrectomy, urethral recurrence was observed in 13 cases (21.7%), while no recurrence was observed in the cases treated with urethrectomy. The average period of time from cystectomy to urethral recurrence was 24.7 months (11-39 months). Urethral cancer of such early stages as pIa and pIb were found in 3 and 6 cases, respectively. Stage pT2 was found in 4 cases. Grade 1 cancer was found in 3 cases, grade 2, in 5 cases, and 3 in 5 cases. The proximal end of the perpendicular urethra was found to be the most frequent site for recurrence with 11 cases exhibiting recurrence at this location and 2 cases at the mid-portion of the perpendicular urethra. Many cases exhibited multiple recurrence of tumor of visually grayish, velvety and non-papillary type which was histologically all transitional cell carcinoma. Bladder tumor with higher grade tended to cause urethral cancer recurrence with higher grade. Bladder tumors at multiple locations from the trigone to the lateral and posterior walls tended to cause recurrence in the urethra (p less than 0.05). Of all the cases, 10 cases underwent urethrectomy and 2 cases penectomy. 12 cases received chemotherapy and 5 cases radiation therapy as postoperative adjuvant treatments.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1990

[Clinical study on 32 patients who underwent parathyroidectomy at Osaka City University Hospital].

We retrospectively reviewed 32 patients who underwent parathyroidectomy at our hospital for the last fourteen years. 1) Clinical appearance of primary hyperparathyroidism was in younger age in women. 2) In previous history or at the time of PTX, 9 patients had malignant tumors including 6 thyroid cancers, 36% of the patients with out bone related symptoms had a remarkable decrease in bone mineral content. 3) After PTX, none of patients had recurrent urolithiasis and bone mineral content of all patients was significantly increased in a short time. In addition, upper GI complaints were improved, or hypertension was partially normalized. However, renal insufficiency remained unchanged. 4) In preoperative localization study, Ultrasound sonography (US) demonstrated the best accuracy rate of 88% when only one gland was involved. US was able to detect multiple gland involvement only in 20% of 5 cases. 5) Hypercalciuria was recognized as one of the risk factors of stone formation in patients with primary hyperparathyroidism.

Adenoma↗
PubMed1990

[Experience with extracorporeal shock wave lithotripsy for urinary stone. Factors for requiring more than two ESWL treatments and its result].

Extracorporeal shook wave lithotripsy (ESWL) was performed for the treatment of 1277 urolithiasis patients at Osaka City University Hospital from July, 1985 to December, 1988. A total of 1788 ESWL treatments were carried out using Dornier HM3 kidney lithotripter. 964 patients (75.5%) underwent only one ESWL treatment, while 313 patients (24.5%) more than two ESWL treatments. We retrospectively examined the factors for requiring more than two ESWL treatments. Not only stone number, size and location, but fragility were considered to be the main causes for requiring more than two ESWL treatments. According to component analysis of ureteral stones, which were hard and resistant to shock wave, calcium apatite content of these stones turned out to be high (p less than 0.001). As for fragility, the residual stones created by ESWL were more difficult to be disintegrated that the nontreated stones of the same size (p less than 0.05). "Fragility" of the stones before shock wave and residual stones after ESWL are considered to be a major problem in ESWL treatment of urinary stones to be solved in the years to come.

Adolescent↗
PubMed1990

In vivo inhibition of superoxide production and protein kinase C activity in macrophages from vitamin E-treated rats.

Rat peritoneal macrophages, which were induced by intraperitoneal injection of vitamin E for 6 successive days, contained 387.6 to 569.0 ng alpha-tocopherol/10(6) cells and produced 0.9 to 1.5 nmol O2-/min/10(6) cells following stimulation by phorbol myristate acetate (PMA). On the other hand, control macrophages contained 1.7 ng alpha-tocopherol/10(6) cells and produced 3.9 to 4.5 nmol O2-/min/10(6) cells. The particulate fraction of macrophages from vitamin E-treated rats contained 285.2 to 294.4 ng alpha-tocopherol/10(6) cells and showed scarcely any protein kinase C activity, whereas the specific activity of control rats showed 323 to 357 pmol/min/mg protein. From these results, we concluded that vitamin E seems to decrease O2- production from macrophages stimulated with PMA through inhibition of protein kinase C.

Animals↗
PubMed1990

[Intravesical instillation chemotherapy of anticancer agents including cylocide: studies of prophylactic effects on the recurrence].

We studied the efficacy of intravesical instillation chemotherapy of anticancer agents including cylocide (CA) in the prevention of recurrence of bladder tumor after surgery. Totally 60 patients with superficial bladder tumor were enrolled into the study. The patients were randomly assigned to either one of three groups: CA 300 mg alone, CA 200 mg + mitomycin C (MMC) 10 mg, and CA 180 mg + adriamycin (ADM) 20 mg. These drugs were initially instilled once a day for one week, and then once a month until 2 years after surgery. Thereafter, the patients were followed up without instillation. The cumulative non-recurrence rates in the CA group was 76.5, 60.0 and 60.0% at 1, 2 and 3 years after the removal of bladder tumor, respectively, while that in the CA + MMC treated group 90.9, 75.3, and 75.3% and that in the CA + ADM treated group, 95.1, 82.9 and 82.9%, respectively. The recurrence rate in the CA, CA + MMC and CA + ADM treated group was 35.3, 27.3 and 19.0%, respectively, the recurrence indices 1.84, 1.07 and 0.74, and the mean times between recurrence 10.8, 16.5 and 18.0 months, respectively. Side effects were noted in 3 of the 17 cases (17.6%) in the CA group, in 3 of the 22 cases (13.6%) in the CA + MMC group and in 3 of the 21 cases (14.3%) in the CA + ADM treated group. These data show that intravesical CA instillation in combination with MMC or ADM is more effective for the prevention of recurrence than that of CA alone.

Actuarial Analysis↗
PubMed1990

[Evaluation of the results of extracorporeal shock-wave lithotripsy (ESWL) for solitary upper urinary tract stone].

At Osaka City University Hospital, we performed extracorporeal shock-wave lithotripsy (ESWL) for 1277 patients in a total of 1788 sessions using Dornier kidney lithotripter Model HM III from July, 1985 to the end of December, 1988. Among the patients with a solitary stone, 911 cases were available for the follow-up study and we have compared the results among these cases in respect to the stone location and size. The results obtained were as follows: the ratio of kidney stone to ureter stone was found to be 2.2:1 in male, and 3.8:1 in female patients. This indicates that ureter stones are more frequently found in male than in female patients. In addition, we compared the size of kidney stones found in the patients including 415 male and 243 female patients. Stones larger than 20 mm were more frequently found in female than in male patients. Moreover, a stone composition study of these patients showed that the contents of both phosphate calcium and magnesium ammonium phosphate were higher in female than in male patients. ESWL performed against stones at pelvis and calyces exhibited the best results. The results obtained with the stones less than 20 mm in diameter were especially favorable with a success rate of 100% for the stones less than 10 mm and 83% for the stones 10-20 mm, in diameter, while the results with the stones larger than 20 mm in diameter were rather poor with a success rate of 31%. ESWL performed against ureter stones showed poor results with a success rate of 63% for the stones smaller than 20 mm in diameter.

Calcium Phosphates↗
PubMed1989

Role of the kallikrein-kinin system in human pancreatitis.

Various factors in the kallikrein-kinin system were evaluated in acute and chronic pancreatitis. It was noted in particular that plasma trypsin and glandular kallikrein increased markedly in acute phase of pancreatitis and its correlation with amylase was observed. Plasma prekallikrein (PPK) decreased in acute pancreatitis, but increased in chronic pancreatitis. A negative correlation was noted between PPK and kallikrein like activity. Both HMW and LMW kininogen decreased in acute pancreatitis. It was presumed from these findings that the increase in kinin and its activation at the acute phase of pancreatitis might be due to kallikrein or trypsin originating from the pancreas.

Acute Disease↗