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S Oyama

Publications and source records attributed to S Oyama.

At least 37 records · Page 2Linked to original sources
PubMed1994

[The treatment and clinical issue of gastric cancer with infiltrating the adjacent organs].

We discussed the advances and clinical issue including complications in the treatment of gastric cancer infiltrating the adjacent organs. Recent years, the proportion of the patients with gastric cancer infiltrating the adjacent organs are decreasing, but there isn't remarkable advances in the treatment result of them. That is due to the fact that about one half of them has distant metastasis, such as peritoneal dissemination or liver metastasis. Whatever the survival rate of the patients who was performed combined resection is better than unresected cases. The postoperative complications of the combined resection cases is two times as much as the uncombined resected cases. Therefore we should perform combined radical resection for the patients without distant metastasis, and for the patients with distant metastasis, we should perform palliative surgery for the purpose of improving QOL.

Adult↗
PubMed1994

[Meta-analysis of 10 postoperative adjuvant chemotherapies for gastric cancer in CIH].

Six adjuvant chemotherapy protocols with 10 chemotherapy regimens were subjected to meta-analysis with an aim to clarify the survival benefits of adjuvant chemotherapy in gastric cancer. All adjuvant chemotherapies were compared with surgery alone, in cases from 1959 to 1982 in the Cancer Institute Hospital, Tokyo in the setting of controlled randomized study; and 1,177 gastric cancer patients with curative surgery were entered the studies. Pooled odds ratio and its 95% confidence interval was 0.63(0.51-0.78). The results suggested the survival benefits of adjuvant chemotherapy with mitomycin C and/or 5-fluorouracil in gastric cancer.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1994

[Treatment of recurrent gastric cancer].

The recurrence rate of resected gastric cancer was 31.9%. The rate was in creasingly higher in proportion to the lack of radicality. The most common type of recurrence was peritoneal dissemination, followed by hematogeneous metastasis, local recurrence, and distant lymph node metastasis. The treatments for recurrence were surgery (9.3%) and chemotherapy (16.1%). Systemic chemotherapy (intravenous iv) was common, and local chemotherapy (intraarterial ia, intraperitoneal ip) was rate. The efficacy of systemic chemotherapy (iv) for recurrent gastric cancer without local recurrence was suggested. The efficacy of local chemotherapy (ia) was suggested for peritoneal dissemination and local recurrence.

Adult↗
PubMed1992

[Cell cycle analysis of endometrial cancer cells in vitro treated with growth factor and steroid hormone].

The aim of this study was to overtake the mechanism of the control system in endometrial cancer cell line in vitro. Ishikawa cell (IK cell) and HEC-1 cell (HEC cell) derived from endometrial cancers were cultured with serum free medium (SFM-101). IK cell possessed Estrogen receptor (ER), Progesterone receptor (PR), Epidermal growth factor (EGF) and its receptor (EGFR). HEC cell had PR, EGF, and EGFR, however HEC cell did not keep ER. EGF stimulated the growth of IK cell, but the growth of HEC cell was not stimulated by EGF. S phase cells were increased by EGF in IK cell, but were not increased by EGF in HEC cell. The growth of IK cell was stimulated significantly by EGF and Estradiol-17 beta (E2) +EGF than control. However, E2+EGF did not stimulate the growth of IK cell than EGF significantly. Danazol (D) and D+EGF inhibited the growth of IK cell significantly than control. S phase cells were decreased by the treatment of D and D+EGF. From our results, EGF stimulated the growth of ER positive endometrial cancer cell, but EGF did not stimulate ER negative endometrial cancer cell. E2+EGF and EGF stimulated the growth of IK cell as a same. However, D inhibited the growth of IK cell that was stimulated by EGF.

Cell Division↗
PubMed1991

Epitope changes on the haemagglutinin molecule of recently isolated H1N1 influenza viruses.

We have studied changes of epitopes on the haemagglutinin molecule (HA) of H1N1 influenza viruses isolated between 1977 and 1986. For this purpose monoclonal antibodies (MAbs) were raised against the HA of the influenza A/England/333/80 and A/Yamagata/120/86 strain viruses. In order to define the amino acid residues responsible for the change of epitopes, we prepared several HA cDNAs modified by site-directed mutagenesis and cloned them into a simian virus 40 expression vector (SVHA). The substitution of glycine with serine at position 125c (suffix indicates presence in H1 but not in H3 subtype HAs) on the HA of the influenza A/USSR/90/77 strain virus resulted in the loss of epitope 110 (epitopes were named after MAbs) and created new epitopes 139 and 15, which were observed on the HA of A/England/333/80 and a few isolates from 1983. These new epitopes disappeared from the HA in some of the isolates in 1983 and most of the isolates in 1984 and 1986. The disappearance of epitopes 139 and 15 seems to be associated with the loss of epitope W18, which was identified on the HA of A/USSR/90/77. We suggested previously that amino acid residue 189 was involved in epitope W18. We therefore expressed an HA protein with two amino acid substitutions at positions 189 and 125c and found that the conversion of glutamine to lysine at position 189 in SVHA-67 prevented the expression of epitopes 139 and 15.

Animals↗
PubMed1991

[Correlation of p105 expression and malignancy in gastric cancers].

The expression of proliferation-associated nuclear antigen p105 of gastric carcinomas was studied by multiparameter flow cytometry and immunohistochemical technique. Content of p105-antigen in cancer cells increased with cell cycle progression, and increased more rapidly in cells in late-S phase than in cells in G0 and early S-phases. Cells in M-phase exhibited a dramatic increase in the amount of the antigen, and the amount of IF intensity of mitotic cells were approximately 5-10-fold greater than that of cells in G1- and S-phases. Immunohistochemical technique demonstrated that patients with lymph node metastasis are more likely to have high p105 positive rates than node-negative patients. The mean p105 positive rates of aneuploid tumors were significantly higher than those of diploid tumors. These results indicate that the measurement of p105 positive rates may be a powerful prognostic indicator of gastric carcinoma.

Aneuploidy↗
PubMed1991

[Expression of proliferation associated nuclear antigen P-105 in human gastric cancers: as a new marker for metastasis].

Expression of proliferation associated nuclear antigen P-105 was examined with flow cytometry in forty-three patients with advanced gastric cancer. Expression of P-105 was observed abundantly in cancer, about four times than normal mucosa, but little in normal gastric mucosa. We evaluated the expression of P-105 in cancer as P-105 intensity: mean FITC levels of G0G1 of the cancer cells/those of normal cells. The P-105 intensity did not correlate with DNA index or S-phase fraction. Furthermore, it did not correlate with histologic type, stromal type, infiltrating type, and gross appearance. However, P-105 intensity was significantly higher in the patients with hepatic metastasis, and lower in those with peritoneal dissemination than those without metastasis, respectively. From the results, it was supposed that P-105 intensity might be a useful indicator for metastatic type different from those previously reported in human gastric cancers.

Antigens, Neoplasm↗
PubMed1991

Antigenic analysis of recent H1N1 influenza viruses with monoclonal antibodies.

Antigenic analysis of recently isolated H1 influenza viruses was performed using haemagglutination inhibition (HI) assay with monoclonal antibodies to the haemagglutinin (HA) subunit. Tests using monoclonal antibodies against the HA of the A/England/333/80 (H1N1) and A/Yamagata/120/86 (H1N1) viruses revealed that the major antigenic drift occurred in 1985 or 1986 and A/Dunedin/6/83-like virus became a major strain after 1986.

Antibodies, Monoclonal↗
PubMed1991

[In vitro chemosensitivity test using collagen gel matrix for human gastric carcinomas].

The usefulness of an in vitro human tumor culture system using a specialized collagen gel matrix derived from pig skin was retrospectively evaluated as a chemosensitivity test for human gastric carcinomas. Seven xenograft tumors derived from human gastric cancers were examined by this system (CGM assay) and compared with the data obtained by a nude mice assay (NM assay) and a succinic dehydrogenase inhibition test (SDI test). Xenograft tumors had three-dimensional growth on the collagen gel matrix like that in vivo. There was increasing cell kill with rising cytotoxic drug concentration. When drug sensitivity was evaluated as effective based on an inhibition rate of 40% or more in the CGM assay, drug sensitivity as measured by the CGM assay corresponded with that measured by the NM assay for all xenograft tumors but not the SDI test. This system could be applied for chemosensitivity test of scirrhous gastric carcinomas. It was suggested that the CGM assay may be more like an in vivo like chemosensitivity test and clinically useful testing for the patients with gastric cancer, including scirrhous one.

Animals↗
PubMed1990

[Malignancy in gastric cancer, with special reference to the distribution of BrdU-labelled cells].

Analysis of the distribution of BrdU-labelled cells was performed on 50 gastric cancers and the results correlated with histologic findings and DNA ploidy patterns. Patients were administered a intravenous infusion of 1g BrdU 1 hour before laparotomy. The resected specimen was fixed in 70% ethanol, embedded in paraffin, and cut into thin sections. The sections were stained by ABC method. The BrdU labelling index (LI) was calculated by counting 1000 tumor cells in superficial, internal and deep layers, respectively. DNA ploidy was analyzed using flow cytometry. The mean of BrdU LI of superficial layer was 19.6%, which was significantly higher than that of internal layer and deep layer. The distribution patterns were classified into three types (labelling types) as follows: Superficial type, BrdU LI of superficial or internal layer was higher than that of deep layer; deep type, BrdU LI of deep layer was higher than that of superficial or internal layer; diffuse type, BrdU LI of each layer was equal. Thirty of 50 cases were superficial type. But in diffuse type (13 cases), incidence of lymph node metastasis, vessel invasion, larger than 4 cm in tumor size, differentiated type and aneuploid were significantly higher than those in superficial type.

Bromodeoxyuridine↗
PubMed1989

[Effect of UFT on nuclear DNA distribution of gastric and colorectal carcinomas].

To evaluate the effect of UFT on nuclear DNA distribution of carcinoma, we measured the DNA content of biopsy specimens and resected specimens obtained from 18 patients by microfluorometry. The tumors consisted of 7 gastric and 11 colorectal carcinomas. Five patients who received administration of 400mg of UFT (400mg of tegafur) were classified as the chemotherapy group and another 13 patients were classified as the control group. 1) DNA indices of biopsy specimens and resected specimens of the same patients showed almost the same values both in the control group (r = 0.81) and in the chemotherapy group (r = 0.89) (p less than 0.05). 2) S and S + G2M fractions of resected specimens showed almost the same values as compared with those of corresponding biopsy specimen in the control group. However, in the chemotherapy group S and S + G2M fractions of resected specimens showed a tendency to be higher than those of corresponding biopsy specimen (0.05 less than p less than 0.1). This study indicates that the biopsy specimens are sufficient for DNA analysis and that UFT-induced DNA change may be increase of S and S + G2M fraction.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1989

[A clinicopathological studies on gastrointestinal leiomyosarcomas, with special reference to prognosis].

Twenty-five cases of gastrointestinal leiomyosarcomas were subjected to clinico-pathological studies in an attempt to correlate the prognosis with tumor size, mitosis, cellularity and DNA ploidy pattern. Leiomyosarcomas greater than 5cm in diameter had poorer prognosis. Those with mitotic index larger than 3.0/mm2, cellularity larger than 3.0/0.0004mm2, DNA aneuploidy had poorer prognosis. By multiple regression analysis, mitotic index was useful for the prediction of tumor recurrence in earlier postoperative period, but cellularity, tumor size were useful for the prediction of recurrence in later postoperative period. As for the type of tumor recurrence, hematogenous metastasis was observed in 7 cases, peritoneal dissemination in 2 and local recurrence in 4. Four cases with local recurrence had all hematogenous metastasis. Two cases of gastric leiomyosarcomas developing local recurrence were greater than 10cm in diameter and gastric local resection was done for them. One case was diagnosed benign leiomyoma in the rectum histologically, but after trans-anal tumor resection local recurrence and metastasis to the lung occurred. We must pay attention to the surgical margin and the surface of tumor dissection during of the tumor, especially in larger tumors. Aggressive surgical resection is efficient for the treatment of recurrent tumors.

Cell Count↗