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Biomedical subjects

M Sakurai

Publications and source records attributed to M Sakurai.

At least 703 records · Page 39Linked to original sources
PubMed1988

Thymoma: results with complete resection and adjuvant postoperative irradiation in 141 consecutive patients.

A series of 141 patients with thymoma was studied with regard to the way in which complete resection followed by postoperative radiation therapy influenced prognosis according to the stage and histologic type of thymoma. Postoperative radiation therapy (30 Gy in 3 weeks to 50 Gy in 6 weeks) was performed in 73.1% of the patients. Thirty-five of 48 patients with thymoma invading the surrounding tissues (stage III) underwent complete resection, with survival rates of 100% at 5 years and 94.7% at 10 and 15 years. The prognosis in these patients was comparable with those in 45 patients with no invasion (stage I) and in 33 patients with capsular invasion (stage III), all of whom underwent complete resection. Complete resection was done in 18 of 26 patients with epithelial cell thymoma, and there were no deaths by tumor until 15 years after the operation. There were no statistically significant differences in the survival rates of patients undergoing complete resection according to cell type (33 of 36 patients with lymphocyte predominant type and 61 of 77 patients with mixed cell type). The survival rate in six patients with epithelial cell type who underwent subtotal resection was not significantly different from that of 12 patients who underwent biopsy alone. Our findings indicate that complete resection of thymoma followed by postoperative radiation therapy results in a "benign" postoperative course, regardless of the stage and histologic type. Therefore, an aggressive surgical approach, such as resection of the superior vena caval system followed by reconstruction with a ringed polytetrafluoroethylene graft and/or complete pleuropneumonectomy, is justified for advanced thymoma, although the long-term results of such extended operations are still unclear.

Adolescent↗
PubMed1988

Soft tissue sarcomas in Osaka, Japan (1962-1985): review of 290 cases.

Two hundred and ninety patients with soft tissue sarcomas (STS) in Osaka, Japan, were reviewed. The patients' ages ranged from one month to 84 years (mean 51 years) with a male to female ratio of 1.23:1. The tumors were located in the extremities (120 cases), the trunk (76 cases), the abdominal cavity (40 cases), and the head and neck (43 cases). Histologically the tumors were classified as malignant fibrous histiocytoma (101 cases, 34.8%), liposarcoma (28 cases, 9.7%), synovial sarcoma (24 cases, 8.3%), rhabdomyosarcoma (23 cases, 7.9%), neurogenic sarcoma (20 cases, 6.9%), fibrosarcoma (16 cases, 5.5%), leiomyosarcoma (16 cases, 5.5%) and others. From the present study, it appears that there are no significant differences between STS in Japan and Western countries with regard to the distributions of histological type and primary site.

Adolescent↗
PubMed1987

Chromosome abnormalities in malignant lymphoma in patients from Saitama.

Clonal chromosome abnormalities were found in 89 (97%) of 92 patients with non-Hodgkin's malignant lymphoma including immunologically determined 34 B- and 25 T-lymphomas; only 3 of 19 T-lymphoma patients examined had serum adult T-cell leukemia/lymphoma-associated antigen antibody. Association of 8q24 translocations with small non-cleaved cell (P less than 0.01) and that of t(14;18) (q32;q21) with follicular histology (P = 0.03) were significant. Several other abnormalities were also found to be correlated with histological or immunological phenotypes: trisomy 5 with diffuse, mixed cell lymphoma (P = 0.03); a break at 3q21 with diffuse, large cell lymphoma (P = 0.04); gain of chromosome 18 or X and rearrangements of 13q with immunoblastic lymphoma (P = 0.02, 0.03, and 0.03, respectively); and rearrangements of 7q with diffuse large cell histology (P = 0.02) and T-cell phenotype (P = 0.02). Multiple clones were more frequently seen in T-cell lymphoma than in B-cell lymphoma (P = 0.01). Structural changes of the long arm of chromosome 4 or 15 and a break in 6p21 were also associated with T-lymphoma (P = 0.03, respectively). Since the frequency of T-lymphoma is significantly higher and that of t(14;18) is significantly lower in the adult T-cell leukemia/lymphoma nonendemic area of Saitama in Japan than in Minnesota in the United States (P less than 0.01), factors affecting the lymphoma-genesis may be different or operating in different intensities in different areas.

Adolescent↗
PubMed1987

Decreased phorbol ester receptor and protein kinase C in P388 murine leukemic cells resistant to etoposide.

A variant P388 murine leukemic cell resistant to 4'-demethylepipodophyllotoxin-9-(4,6-O-ethylidene)-beta-D-glucopyr anoside (etoposide) (VP-16-213) was cloned. The variant P388/VP-16 cell line was 159-fold resistant to 4'-demethylepipodophyllotoxin-9-(4,6-O-ethylidene)-beta-D- glucopyranoside and showed cross-resistance to vincristine (18.9-fold) and Adriamycin (522.9-fold), determined by comparing the 50% inhibitory concentrations in a 48-h growth inhibition assay. To identify the possible role of Ca2+-phospholipid-dependent protein kinase (protein kinase C) in this drug resistance, we studied the specific phorbol ester binding component and protein kinase C in the parent and drug-resistant sublines of P388 cells. The phorbol ester receptor, as expressed by the numbers of sites per cell, significantly decreased in P388/VP-16 (57.6% of control). Scatchard analysis revealed that the variant contained a single class of binding sites. However, no difference was observed in the dissociation constants (Kd), thereby suggesting much the same affinity of receptors between the two lines. Phorbol diester analogues inhibited [20-3H]phorbol-12,13-dibutyrate binding of both the variant and control cell lines, in a stereospecific manner and consistent with their binding potency. The activity of protein kinase C, which is related to the phorbol ester receptor, significantly decreased in the variant cell. The enzyme activity, particularly in the membrane fraction of P388/VP-16 cells, was remarkably decreased. These data suggest that the decrease in the specific phorbol diester receptor and protein kinase C in the variant cells might correlate with the pleiotropic drug resistance.

Animals↗
PubMed1987

Induction of ornithine decarboxylase activity in mouse tissues by phorbol ester is effectively blocked by methylglyoxal bis(butylamidinohydrazone).

Ornithine decarboxylase (ODC) was induced in the liver, lung and brain of the mouse injected intraperitoneally with 12-O-tetradecanoylphorbol 13-acetate (TPA), showing maximal enzyme activity four hours after the injection. The increase of ODC activity was due to the enhanced syntheses of mRNA and protein. The induction of ODC activity by TPA was specifically blocked by methylglyoxal bis(butylamidinohydrazone) (MGBB), a competitive inhibitor of ODC and S-adenosylmethionine decarboxylase, but not by the analog methylglyoxal bis(guanylhydrazone) (MGBG).

Animals↗
PubMed1987

Agreement rates and American-Japanese pathologists' comparability of a modified Working Formulation for non-Hodgkin's lymphomas. An analysis of the cases collected for the Fifth International Workshop on Chromosomes in Leukemia-Lymphoma.

Histopathologic slides of 368 cases collected from 16 institutions around the world for the Fifth International Chromosome Workshop were independently reviewed by a group of five hematopathologists consisting of two Americans and three Japanese. Agreement rates of their diagnoses using the Working Formulation (WF) for non-Hodgkin's lymphomas were studied. A modified classification scheme of the WF was used in order to define cytologic subtypes more specifically, enabling 65 possible diagnostic choices. Data analyses by computer revealed that at least four out of five diagnostic agreements were observed in 290 cases (78.9%). Similar agreements were observed in more than 80% of the cases for most of the categories of the WF, excepting diffuse small cleaved (73.3%), diffuse mixed (64.2%), diffuse large cell (76.5%), and immunoblastic lymphoma (70.2%). Agreement rates between American and Japanese pathologists did not demonstrate statistically significant differences against expected values. It was concluded that the WF was a reliable and useful classification system for multi-institutional as well as international projects, although refinements may be necessary in some categories for better diagnostic agreement.

Humans↗
PubMed1987

Hemophagocytic syndrome complicating T-cell acute lymphoblastic leukemia with a novel t(11;14)(p15;q11) chromosome translocation.

A case of hemophagocytic syndrome that developed in a patient with T-cell acute lymphoblastic leukemia (ALL) with a novel chromosome translocation involving 14q11 is reported. A 15-year-old boy with T-cell ALL in relapse showed leukemic cells with an abnormal karyotype of 46,XY,-15,t(11;14)(p15;q11), +der(15)t(15;?)(p11;?). Pancytopenia and extensive hemophagocytosis by macrophages in the bone marrow were observed after reinduction chemotherapy and again at the terminal stage. At autopsy, infiltration of such cells was also found in other organs. The findings suggested occurrence of hemophagocytic syndrome probably associated with cytomegalovirus (CMV) infection. The t(11;14)(p15;q11) may be a novel translocation specific for T-cell ALL, and conceivably, the association of T-cell ALL with the histiocytosis in this patient may not have been coincidental.

Adolescent↗
PubMed1987

Different karyotypic patterns in early and advanced stage neuroblastomas.

Of 23 untreated and 7 treated (relapsed) neuroblastomas, 14 (11 untreated, 3 treated) had modal chromosome numbers in the diploid (45 to 51), 9 (8 untreated, 1 treated) in the triploid (60 to 77), and 6 (3 untreated, 3 treated) in the hypotetraploid (81 to 88) range, and one (untreated) had hypertetraploidy (100). The near-or-pseudodiploid and hypotetraploid tumors were characterized by numerous structural abnormalities, most frequently of 1p, and frequent presence of double minutes or homogeneously staining regions. The near-triploid tumors were characterized by three almost complete haploid sets of chromosomes, and few structural abnormalities. N-myc amplification was found in five of the near-or-pseudodiploid or hypotetraploid tumors but in none of the near-triploid tumors. Most near-triploid tumors were found in infants at stage I or II, and the near-or-pseudodiploid or hypotetraploid tumors in children at stage II or IV mostly 1 year old or older. Among the untreated patients, all 8 with a near-triploid tumor were alive with no evidence of the disease, and the 11 with a near-or-pseudodiploid tumor had a median survival of only 376 days (P less than 0.05), 7 of the 11 being dead. Thus, the near-triploid patients had well recognized favorable prognostic factors and an excellent prognosis, and the near-or-pseudodiploid patients had unfavorable prognostic factors and a dismal prognosis. The hypotetraploid tumors seemed to have karyotypic and clinical features in common with the near-or-pseudodiploid tumors. We presume that the near-triploid tumors and the near-or-pseudodiploid or hypotepraploid tumors may constitute distinctly different subcategories within neuroblastomas.

Age Factors↗
PubMed1987

The colony inhibition of a new chemotherapeutic agent (KW2152) against human lung cancer cell lines.

The human tumor colony assay was used to evaluate the effect of a new chemotherapeutic agent (KW2152) on colony inhibition of four non-small cell lung cancer cell lines and a mouse cell line. With continuous exposure experiments, KW2152 induced greater than or equal to 70% colony inhibition of PC-7 (human adenocarcinoma), PC-10 (human squamous cell) and PC-13 (human large cell) at a drug concentration of 10 mcg/ml. In one hour exposure experiments, KW2152 caused a significant reduction in colony formation (less than or equal to 30% of control) only at the highest concentration tested (100 mcg/ml). KW2152 showed significant in vitro activity against human non-small cell lung cancer cell lines. Due to these promising results, it was suggested that KW2152 should be evaluated in clinical trials.

Antineoplastic Agents↗
PubMed1987

The different effects of recombinant human tumor necrosis factor on rat fibrosarcoma sublines.

The antitumor effect of recombinant human tumor necrosis factor (rH-TNF) on two clones of rat fibrosarcoma with different metastatic potential to lymph nodes was examined. The colony formation of clone A, which has high metastatic potential, was completely inhibited by continuous exposure to rH-TNF at 50 U/ml. In contrast, colony formation of clone G, which has low metastatic potential, was not inhibited by high concentrations of rH-TNF (10,000 U/ml). The inhibitory effect of rH-TNF on colony formation by clone A was also observed with a 1-h exposure to rH-TNF. This effect was time and concentration dependent, as determined by the colony assay, 3H-thymidine uptake assay, and 51Cr-release assay. 3H-thymidine and 3H-uridine uptake per cell of clone A exposed to rH-TNF was not decreased. This suggests that the mechanisms of the antitumor effect of rH-TNF were not due to inhibition of DNA and RNA synthesis of tumor cells. In vivo growth and lymph node metastases of clone A inoculated i.p. to Donryu strain rats were completely suppressed by 14 consecutive i.p. injections of 10(5) or 10(6) U/kg per day of rH-TNF. On the other hand the growth of clone G was not influenced by rH-TNF administration.

Animals↗