Biomedical subjects

O Maeda

Publications and source records attributed to O Maeda.

At least 73 records · Page 4Linked to original sources

PubMed1992

Comparative studies on heat stability and autolysis of scallop (Patinopecten yessoensis) calpain II-like proteinase and rabbit calpain II.

1. The scallop calpain-like proteinase is about five times more labile than the rabbit calpain II upon heat treatment at 35 degrees C. 2. By autolysis of the scallop proteinase of two 100 kDa subunits, 90, 45 and 30 kDa fragments were formed. Thereby the activity decreased monophasically in the presence of millimolar order of Ca2+, but did not increase in the presence of micromolar order of Ca2+ unlike the rabbit calpain II.

Animals↗

PubMed1992

Accumulation of cis-diamminedichloroplatinum (II) and its analogues in sensitive and resistant human ovarian carcinoma cells.

Human ovarian carcinoma cell line (NOS2), established from a patient with serous cystadenocarcinoma of the ovary, has been exposed to a stepwise increase in cis-diamminedichloroplatinum (II) (CDDP) concentration to produce a CDDP-resistant cell line NOS2CR) as an experimental model for resistance to CDDP. NOS2CR cells showed a 7-fold resistance to CDDP and a lesser degree of cross-resistance to diammine (1,1-cyclobutanedicarboxylato)-platinum (II) (CBDCA) and (-)-(R)-2-aminomethylpyrrolidine (1,1-cyclobutanedicarboxylato) platinum (II) (DWA2114R). In the absence of CDDP, cross-resistance to DWA2114R was reduced to the original level by 2 months, although 83% resistance to CDDP remained up to 6 months. To investigate CDDP-resistant mechanisms, alterations in the intracellular accumulation of CDDP and analogues were assayed by atomic absorption. In both NOS2 and NOS2CR cells, accumulation of CDDP increased linearly with time and was concentration-dependent. NOS2CR cells demonstrated 71, 52 and 12% reduction in accumulation of CDDP, CBDCA, and DWA2114R, respectively. These reductions did not seem to be due to P-glycoprotein, because expression of multidrug-resistant 1 gene was not detected in either NOS2 or NOS2CR cells. These studies indicate that the mechanisms of resistance to CDDP and analogues in NOS2CR cells are related in the main to reduced intracellular accumulation of drugs. DWA2114R might be helpful to treat CDDP-resistant and recurrent tumors which were treated by CDDP.

Antineoplastic Agents↗

PubMed1992

[Surveillance after orchiectomy for stage I testicular seminoma].

The results of treatment by orchiectomy and radiotherapy for stage I testicular seminoma are excellent with cure rates exceeding 95% and relapse rates less than 5%. However, after the development of successful surveillance programs for stage I nonseminomatous testicular cancers, the role of radiotherapy has been questioned by some authors and they proposed a "surveillance policy" for these patients. The purpose of this study was to determine the percentage of patients cured by orchiectomy alone, percentage who ultimately required therapy for occult metastases, site of recurrence, and over-all cure rate and treatment morbidity. And these data were compared with those of adjuvant radiotherapy group retrospectively. Twenty seven patients were treated with adjuvant radiotherapy (RT group). Since 1986, 23 patients with stage I testicular seminoma entered the "surveillance only" protocol at our institution (S group) with a follow-up between 14 and 70 months (median 43 months). Informed consent for the policy of surveillance was obtained. Follow up consisted of physical examination, determination of serum tumor markers and chest X-ray bimonthly for 2 years, every 3 months for 1 year, every 6 months for 2 years and annually thereafter to 10 years. CT scans were performed every 4 months for 3 years, every 6 months for 2 years. Two patients in S group (8.7%) relapsed at 4 and 7 months after orchiectomy with nonbulky retroperitoneal disease (less than 5 cm in diameter), whereas only 1 (3.7%) irradiated patients did so after 4 months.

Adult↗

PubMed1992

[Surgical treatment under extracorporeal circulation for renal cell carcinoma with tumor thrombus in inferior vena cava].

Three cases of renal cell carcinoma with tumor thrombus extending into the inferior vena cava are reported. Radical nephrectomy and thrombectomy were performed under extracorporeal circulation in all the cases. The level of tumor thrombus was preoperatively determined by computed tomography, magnetic resonance imaging or venacavography. The tumor thrombus extended into the right atrium in one, and above the hepatic vein in two cases. One patient whose thrombus reached the right atrium died of multiple metastasis of renal cell carcinoma 5 months after operation. Another patient with lung metastasis was given interferon-alpha and is alive 5 months after operation. The other patient is clinically free of disease and in good health 7 years after operation. We believe that extracorporeal circulation allows an opportunity to resect the tumor thrombus in a controlled situation, and makes the operation safer.

Aged↗

PubMed1992

[Spontaneous peripelvic extravasation associated with primary ureteral tumor: a case report].

A case of spontaneous peripelvic extravasation associated with primary ureteral tumor is reported. A 56-year-old woman presented with left flank pain. Excretory urogram and abdominal computed tomographic (CT) scan demonstrated left hydronephrosis with extravasation of contrast materials around the renal pelvis. Retrograde pyelogram showed the filling defect in the left upper ureter. Under diagnosis of ureteral tumor, total nephroureterectomy was performed. Histological findings revealed transitional cell carcinoma. 80 cases of spontaneous peripelvic extravasation in Japan were reviewed and discussed briefly.

Carcinoma, Transitional Cell↗

PubMed1992

[Diagnosis of ovarian tumors by transvaginal Doppler ultrasound with color flow imaging].

Ovarian carcinoma is a silent disease with few symptoms. Early detection of ovarian cancer is difficult. Transvaginal Doppler ultrasound with color flow imaging is a new technique in the evaluation of gynecological diseases. This method was used in the diagnosis of ovarian tumors in 39 women who were treated in the Department of Obstetrics and Gynecology, Nagoya University Hospital. Wave forms of the parenchymal tumor arteries or tumor surface arteries were compared by according to the pulsatility index (PI). 1/PI was 0.69 +/- 0.04 in benign tumor and 2.33 +/- 1.36 in malignant tumors (p less than 0.01). When the cutoff value of 1/PI was set at 0.8 (cutoff value of PI: 1.25), the accuracy of diagnosis was 84.6% (33/39). The accuracy of ultrasonographic pattern classification and CA125 were 74.4% (29/39) and 53.8% (21/39), respectively. In 18 tumors with low CA125 (less than 35 U/ml), 5 of 7 malignant tumors (71.4%) had high 1/PI (greater than 0.8), and benign tumor, low 1/PI (less than 0.8) or non-detectable wave forms. This procedure should prove to be useful in the diagnosis of ovarian cancer.

Adult↗

PubMed1992

Transvaginal Doppler ultrasound with color flow imaging in the diagnosis of ovarian cancer.

Transvaginal Doppler ultrasound with color flow imaging is a new technique for the evaluation of gynecologic diseases. This method was used for the diagnosis of ovarian tumors in 24 women treated in the Department of Obstetrics and Gynecology, Nagoya University Hospital, Japan. Waveforms of the parenchymal tumor arteries or tumor surface arteries were compared using values of the pulsatility index (PI). The value for 1/PI was 0.69 +/- 0.05 in benign tumors and 1.87 +/- 0.65 in malignant tumors (P less than .01). When the cutoff value of 1/PI was set at 0.8 (cutoff value of PI was 1.25), the accuracy of diagnosis was 95.8% (23 of 24). Among 11 tumors with low CA 125 (less than 35 U/mL), all five malignant tumors had high 1/PI (above 0.8), and all benign tumors had low 1/PI (less than 0.8) or nondetectable waveforms. Based on the findings of this study, color flow Doppler proved to be useful for diagnosis of ovarian cancer.

Adult↗

PubMed1991

[Combination chemotherapy with ifosfamide (or cyclophosphamide), adriamycin, cis-platinum and peplomycin (IAPP) for hormonally resistant metastatic prostatic cancer].

From January, 1986 to April, 1990, combination chemotherapy with ifosfamide (or cyclophosphamide), adriamycin, cis-platinum and peplomycin was performed in 15 patients with hormonally resistant metastatic adenocarcinoma. Three patients had partial response (PR) and 9 remained objectively stable (ST). The median response duration of PR + ST (12) was 5.7 months (range 2.8 to 18.0+). Three patients progressed while on this therapy. Of 8 patients with prior treatment of chemotherapy or chemo-hormonal therapy, 6 achieved an objective response (2 PR, 4 ST). Severe toxicities occurred in 2 patients. One died of lung fibrosis induced by peplomycin and the other received urinary diversion for persistent hemorrhagic cystitis. These results compare favorably with previous reports of chemotherapy treatment of metastatic prostatic cancer patients who failed on hormonal manipulation. However, careful treatment is needed for lung fibrosis and hemorrhagic cystitis.

Aged↗

PubMed1991

[Incontinent urinary diversion].

We analyzed 237 patients who underwent total cystectomy with ileal conduit urinary diversion or cutaneous ureterostomy at the Center for Adult Diseases, Osaka. One-hundred and eighty-eight patients underwent ileal conduit diversion and 49 patients underwent cutaneous ureterostomy. No patient died within 30 days after the operation, but two patients who underwent ileal conduit diversion died of postoperative complications within 2 months. Early complications occurred in 94 patients (50%) in the ileal conduit group and in 18 patients (37%) in the ureterostomy group. Late complications occurred in 85 patients (45%) in the ileal conduit group and in 23 patients (47%) in the ureterostomy group. Frequent early complications in the ileal conduit group were wound infection (29%), and intestinal complications (13%) which included ileus and upper urinary tract complications (12%). The most frequent late complications were stomal complications (26%) which included peristomal dermatitis stomal stenosis, parastomal hernia, and stomal prolapse, and upper urinary tract complications which were noted in 27 patients (14%).

Aged↗

PubMed1991

[Clinical results of total prostatectomy].

Radical surgery was administered to 63 patients with prostatic carcinoma, of whom 48 were put under total prostatectomy, 13 under cystoprostatectomy and 2 under pelvic exenteration. Adjuvant therapy was given in three forms: pretreatment to 31 patients, castration to 44 patients and pelvic lymphadenectomy to 39 patients. The 7 patients in stage A survived without carcinoma. Of the 25 patients in stage B, recurrence was seen in 7 patients but there were no deaths and the 5- and 10-year cumulative survival rates were both 86%. Of the 24 stage C patients, 8 developed recurrence, 4 died with the disease, and the 5 and 10 year cumulative survival rates were 82% and 55% respectively. There were 7 stage D patients, of whom 3 developed recurrence and 2 died, and these patients had a 5 year cumulative survival rate of 86%. The results demonstrated that total prostatectomy with suitable adjuvant therapy is useful for advanced carcinoma as well as clinically early stage carcinoma.

Aged↗

PubMed1991

[Clinical study of incidental prostatic carcinoma].

At the Center for Adult Diseases, Osaka, between 1961 and 1987, 28 cases (1.8%) of incidental prostatic adenocarcinoma were detected by transurethral or subcapsular prostatectomy for clinically benign prostatic hypertrophy (1388 cases) and cysto-prostatectomy for urinary bladder carcinoma (156). Nine (32%) and 19 (68%) cases were in stages A1 and A2, respectively. Of the 19 A2 cases, 9 were well, 9 were moderately and 1 was poorly differentiated adenocarcinoma. Five of the A2 and 1 of the A1 progressed into clinical carcinoma, but none of these patients died of the cancer. Four of these 5 A2 patients had received no treatment postoperatively and one received castration. The intervals from diagnosis to progression ranged from 11 to 78 months. The survival rates at 5 and 10 years with A1 were 75% and 75%, and those with A2 were 80% and 37%. We conclude that the patients in stage A2 should be treated because stage A2 tumors, especially those with no treatment, progress at a higher frequency than stage A1 tumors.

Adenocarcinoma↗

PubMed1991

[Rectal metastasis of prostatic cancer causing annular stricture: a case report].

A 61-year-old man diagnosed with poorly differentiated adenocarcinoma of the prostate (T4 NxM0, stage C) underwent endocrine therapy. The reduction of the tumor was recognized but soon annular rectal stricture appeared. In spite of the subsequent chemotherapy, symptoms aggravated. Then total pelvic exenteration and colostomy were performed. Prostate was easily separated from the rectal wall and the tumor continuity was not proved. Immunohistochemical inspection indicated that the origin of the tumor cells of the rectum was the prostate. Histopathological examination of the rectum using the step section method showed no trace of cancer invasion but many cancer cells in the intramural lymphatic duct. We concluded that adenocarcinoma of the prostate metastasized to the rectum by way of lymphatic flow and caused the annular stricture of the rectum.

Adenocarcinoma↗

PubMed1990

Mitomycin C cross-resistance induced by adriamycin in human ovarian cancer cells in vitro.

We prepared Adriamycin-resistant cancer cells by exposing an ovarian serous cystadenocarcinoma cell line to the drug. The resistant cells also showed cross-resistance to a wide variety of other compounds, including vincristine, vinblastine, actinomycin D, daunorubicin, mitomycin C and carboquone. Against vincristine, the cells showed a greater than 5,000-fold increase in resistance, far surpassing their resistance to the selection drug. The resistant cells displayed a decrease in intracellular Adriamycin content and an increase in the mRNA of the mdr-1 gene coding for P-glycoprotein, with no amplification of the DNA. In revertant cells, resistance to Adriamycin was lost, but that to mitomycin C was maintained. Adriamycin resistance was partially overcome by the addition of verapamil or cyclosporin A, but cross-resistance to mitomycin C was not influenced at all. These results strongly suggest that the resistance to mitomycin C observed in our Adriamycin-resistant cells was due to some other mechanism than that causing multidrug resistance.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed1990

Solitary neurofibroma of scrotum.

We report a case of solitary neurofibroma of the scrotum. These tumors, which arise from perineural and Schwann cells, commonly occur throughout the body but they rarely have been reported to originate in the scrotum. No stigmata of von Recklinghausen's disease were identified.

Adult↗

PubMed1990

[Upper urinary tract tumors following bladder cancer].

We treated in total 795 patients with primary transitional cell carcinoma of the urinary bladder between April, 1964 and December, 1988. Eighteen patients of them had upper urothelial cancer during the follow-up period. Thirteen of the 18 patients had received transurethral resection for the initial bladder cancer, while 3 total cystectomy and 2 segmental resection. The over-all incidence of bladder cancer patients who subsequently developed upper urinary tract tumors was 2.3 per cent. The interval between initial treatment of the bladder cancer and treatment for the upper urinary tract tumor ranged from 2 to 74 months (median 20 months). The five-year survival rate after treatment for the upper urinary tract tumor was 31.7 per cent. We conclude that the following are high risk patients for development of upper urinary tract recurrences: 1) patients with bladder cancer near orifices, 2) patients with recurrent bladder cancer under bladder preserving treatment for a long time, 3) patients with G2 multifocal bladder cancer.

Aged↗

PubMed1990

[Production of monoclonal antibodies against human bladder cancer cells and application to immunohistochemical analysis of bladder cancer].

Two hybridomas secreting two monoclonal antibodies IgG1 B1.4 and IgG2a B1.6 were obtained by immunizing BALB/c mice with human bladder cancer cell line EJ-1. In immunohistochemical staining of cryopreserved tissues, B1.4 reacted with 0 of 9 grade 1 TCC, 6 of 11 grade 2, all of 6 grade 3 and five metastatic specimens. The antigen recognized by B1.4 was not expressed by normal urothelial cells but were expressed by vascular endothelial cells and muscle of tunica media. The target antigen of B1.6 was expressed by normal urothelial cells and all grade of TCC. In this study, it was demonstrated that poorly differentiated bladder cancer and metastatic specimens of bladder cancer express a vascular carbohydrate antigen. Taking the escape mechanism of immune surveillance, into consideration, it is possible that the antigen recognized by B1.4 is an indicator of metastatic potential of bladder cancer.

Animals↗

PubMed1990

[A case of retroperitoneal Hodgkin's disease with dysuria].

A case of retroperitoneal Hodgkin's disease with dysuria is reported. A 56-year-old man visited our hospital with the complaints of dysuria and lower abdominal mass. On physical examination, an unmovable hard smooth mass of fist size was palpable in the lower abdomen and prostate was slightly swelling by rectal digital examination. Excretory urography demonstrated medial deviation of left lower ureter and bladder deformity. Retrograde urethrocystography showed deviation and compression of prostatic urethra. On CT, tumors were composed of several round masses, which surrounded the left common iliac artery on angiography. Surgical extirpation was carried out and histological examination revealed Hodgkin's disease. As postoperative treatment, chemotherapy with cyclophosphamide, adriamycin, vincristine and prednisolone was performed, and 30 months after the operation the patient was asymptomatic.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1989

Effect of aging on presynaptic alpha 2-adrenoceptor mechanisms in guinea pig ileum.

1. Presynaptic alpha 2-adrenoceptor mechanisms in electrically stimulated longitudinal muscles of ilea isolated from 3, 10, 20 and 47 week-old guinea pigs were studied by analysis of the concentration-response curves of noradrenaline, a full agonist, and clonidine, a partial agonist, and the Scatchard plot of specific binding of [3H]-p-aminoclonidine to synaptosomal fractions from the longitudinal muscle of guinea pig ileum. 2. The pD2 value of noradrenaline and the maximum contraction induced by clonidine increased with age from 3 to 20 weeks and there after decreased to 47 weeks, while the pA2 value of yohimbine against noradrenaline did not alter with age. 3. The capacity of the maximum binding sites of [3H]-p-aminoclonidine increased with increasing age (3-20 weeks), while the dissociation constant (Kd) of [3H]-p-aminoclonidine did not change during the same period. 4. The changes in the presynaptic alpha 2-adrenoceptor mechanisms with age are considered to be due to the change in the total concentration of presynaptic of alpha 2-adrenoceptors.

Aging↗