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Biomedical subjects

S Okamura

Publications and source records attributed to S Okamura.

At least 145 records · Page 8Linked to original sources

[Long-term administration of carmofur as a post-operative adjuvant chemotherapy for cervical adenocarcinoma. Cervical Adenocarcinoma Cooperative Research Association].

Cervical adenocarcinoma and adenosquamous cell carcinoma are low in radiation sensitivity, and the prognosis is said to be inferior to that of squamous cell carcinoma. Eleven facilities nationwide participated in the historical control study on the recurrence prevention effect of carmofur (HCFU) administered at 300 mg/day for more than two years postoperatively as an adjuvant chemotherapy to patients with cervical adenocarcinoma or adenosquamous cell carcinoma for which radical operation is possible. Registered for the study was a total of 252 patients: 77 patients for whom administration of carmofur was begun during the period from January 1987 and March 1989, 71 patients (control 1) who were treated for the cancer after January 1982 but did not receive adjuvant chemotherapy, and 104 patients who received adjuvant chemotherapies with other than carmofur (control 2). In analyses with the Kaplan-Meier method, the carmofur administration group demonstrated a better cumulative survival rate and disease free rate than control 1 (no adjuvant chemotherapy), suggesting carmofur was effective in preventing the recurrence of cervical adenocarcinoma and adenosquamous cell carcinoma.

Adenocarcinoma↗

[Evaluation of surgical treatment of gastric cancer in the aged].

Patients with gastric cancer aged 70 years or over were divided into 3 age groups (70-74, 75-79, 80 years or over) and were compared with patients aged 60-69 years, (which is the age group with the highest incidence of stomach cancer) with regard to the incidence of postoperative complications. In addition, factors which might be associated with increased mortality were investigated. There were no significant differences with regard to the incidence of postoperative complications (16-21%) or the mortality rate (0-3%, within 30 days after surgery) between the various age groups. However, the incidence of those complications which later proved fatal was higher in those aged 75 years or over. Factors associated with the development of complications in each age group were the type of surgical technique used, the operation time, and the severity of hemorrhage during surgery. The prognosis for gastric resection was poor in patients aged 80 years or over. Our findings indicated that curative resections should be performed for gastric cancers in the elderly if the general physical condition of the patients permits. A more conservative approach is desirable when the general condition is not favorable.

Age Factors↗

Granulocyte colony-stimulating factor treatment of antithyroid drug-induced granulocytopenia.

The primary objective of this study was to ascertain the effectiveness of granulocyte colony-stimulating factor in the treatment of antithyroid drug-induced granulocytopenia of varying degree. Sixteen patients with Graves' disease with antithyroid drug-induced granulocytopenia (granulocyte counts < 1.0 x 10(9)/L) each received a daily dose of 75 micrograms of granulocyte colony-stimulating factor administered subcutaneously. Within 24 hours of the first injection, the granulocyte count increased (0.6 to 12.3 x 10(9)/L) in all 10 patients with mild granulocytopenia (granulocyte counts between 0.5 and 1.0 x 10(9)/L) and all three with moderate granulocytopenia (granulocyte counts < 0.5 x 10(9)/L). The three remaining patients with severe granulocytopenia (agranulocytic), whose granulocyte counts were zero, did not recover from granulocytopenia until the 6th, 7th, and 14th days of treatment with granulocyte colony-stimulating factor. Examination of bone marrow taken at the onset of the disease in all three agranulocytic patients showed a prominent decrease in granulocytic series, while identical examination in six of eight patients with mild to moderate granulocytopenia showed close to normal granulocytic series. There was no elevation of serum granulocyte colony-stimulating factor concentration in four patients with mild granulocytopenia and one with moderate granulocytopenia at the onset of their disease, whereas those of the remaining three patients with severe granulocytopenia (agranulocytic) increased at onset of agranulocytosis. This information led us to conclude that: (1) granulocyte colony-stimulating factor is effective in the treatment of antithyroid drug-induced mild to moderate granulocytopenia and (2) in severe agranulocytic cases, granulocyte colony-stimulating factor is not effective. Accordingly, we were again reminded of the importance of early diagnosis and treatment of antithyroid drug-induced agranulocytosis.

Adult↗

Differentiation of the rat myelomonocytic leukemia cell line c-WRT-7 by in vitro culture with the rat bone marrow preadipocyte cell line REC A16.

Differentiation of the rat myelomonocytic leukemia cell line (c-WRT-7) was investigated, by co-culture with a rat embryonic bone marrow preadipose cell line (REC A16). Co-cultivation with REC A16, or with conditioned medium from REC A16 cultures (REC-CM), induced differentiation of c-WRT-7 cells to macrophages. A soluble factor(s) produced by REC A16 appeared to be responsible for the differentiation of c-WRT-7. Because REC-CM was associated with colony-stimulating activity on murine marrow progenitors, c-WRT-7 cells were cultured with various colony-stimulating factors (CSF) and it was found that macrophage CSF (M-CSF) significantly induced differentiation of c-WRT-7. We further demonstrated that both the colony-stimulating and differentiation-inducing activities of REC-CM were significantly blocked by anti-M-CSF antiserum. These results suggest that the differentiation of c-WRT-7 is due to M-CSF produced by REC A16. Co-culture of these two cell lines should provide a useful model to study the mechanisms of interaction between leukemia cells and marrow stroma.

Animals↗

Activation of neutrophils NADPH oxidase by PMA: cytosol activity is translocated in phorbol-primed neutrophils.

1. Translocation of cytosol activity in phorbol-primed neutrophils was studied. 2. Prior exposure of PMA or FMLP could potentiate the oxidative response by subsequent heterogeneous stimulus, FMLP or PMA. 3. In FMLP-primed neutrophils, the cytosol had almost the same activity as resting one and cytosol activity was not eluted from the membrane. 4. In PMA-primed neutrophils, however, the cytosol had less activity and cytosol activity was correspondingly eluted from the membrane. 5. These observations suggested that cytosol activity was translocated in PMA-primed cells.

Cytosol↗

Levels of serum granulocyte colony-stimulating factor in patients with cerebrovascular diseases.

The role of leukocytes in the pathogenesis of cerebrovascular disease, in particular, cerebral ischemic disease has recently become a focus of research. Several studies have reported that a positive correlation between increased functional activities of neutrophils and the risk of cerebral ischemic disease. Granulocyte colony-stimulating factor (G-CSF) is known to be not only a granulocyte proliferating factor but also a potent activator of mature neutrophils. In this study, we measured the serum G-CSF levels in 143 patients with cerebrovascular diseases and in 100 patients with other diseases, using our established enzyme-linked immunosorbent assay (ELISA) for G-CSF The minimal detection level was 20 pg/ml G-CSF. In patients with cerebral infarction, G-CSF could be detected in 18.3% and in patients with cerebral hemorrhage, it could be detected in 9.8% of analyzed samples. On the other hand, 6% of the patients with other diseases had measurable levels of G-CSF. The differences among these three groups were statistically significant according to the chi 2 test (p < 0.01). Our findings that there was a significantly high frequency of elevated levels of G-CSF among patients with cerebrovascular diseases, may indicate that the action of G-CSF as a potent activator of neutrophils plays some role in the occurrence of cerebrovascular disease, in particular, cerebral infarction.

Adult↗

Sequential expression of lymphokine genes during phytohemagglutinin-stimulated mitogenesis of normal human peripheral mononuclear cells.

Expression of lymphokine genes including interleukin 2 (IL-2), interleukin 3 (IL-3), granulocyte-macrophage colony-stimulating factor (GM-CSF), interferon gamma (IFN-g), tumor necrosis factor (TNF) and lymphotoxin (LT) were sequentially monitored in peripheral blood mononuclear cells by Northern blot analysis after stimulation with phytohemagglutinin (PHA). The pattern of the expression of lymphokine genes following PHA stimulation as categorized into two types. Type 1 was characterized by rapid appearance of mRNA and by early maximum accumulation. Type 2 was characterized by the prolonged expression and late peak time. Lymphokines including IL-2, IL-3 and GM-CSF belong to type 1 and IFN-g, TNF and LT belong to type 2. Since lymphokines in type 1 are known to act on hematopoiesis in a stimulatory manner, whereas type 2 show an inhibitory action, this sequential expression of lymphokines following mitogen stimulation may reflect some biological feedback mechanism.

Blotting, Northern↗

Augmented production of interleukin 6 by co-culture of human bone marrow adherent cells and human leukemic cells.

Human Dexter-type culture of bone marrow (BM) cells maintains long-term hematopoiesis in the presence of an adherent stromal layer. These BM adherent cells produce hematopoietic growth factors constitutively or inducively and support developing hematopoietic cells. To elucidate the ability of cytokine production by BM adherent cells, the cytokine levels of the culture supernatant of BM adherent cells were measured by enzyme-linked immunosorbent assays. Constitutive production of granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin 6 (IL-6) by the unstimulated BM adherent cells was demonstrated. Levels of granulocyte colony-stimulating factor (G-CSF) were below detectable levels (< 10 pg/ml). The IL-6 level was significantly increased in the co-culture supernatant with KG1 cells or U937 cells (P < 0.01: P < 0.05, respectively). Even when the adherent cells and cell line cells were separated by a membrane filter, the IL-6 level was significantly higher than the control culture (P < 0.01). Co-culture with these cell lines was supposed to induce the increased production of IL-6, which was mediated by some soluble cytokines. The GM-CSF level was not increased in the supernatant co-cultured with any of the cell lines, except with K562 cells. However, K562 cells alone secreted a detectable level of GM-CSF and the increased level of GM-CSF was considered to be due to the production of GM-CSF by K562 cells. G-CSF was not detectable in the supernatant co-cultured with any cell line cells. This result indicates that the cytokine production was regulated by the interaction of BM adherent cells and some leukemic cells.

Bone Marrow↗

Human macrophage colony-stimulating factor levels in cerebrospinal fluid.

Macrophage colony-stimulating factor (M-CSF) levels in the cerebrospinal fluid of 14 patients with meningitis and of 14 patients suffering from a disease other than meningitis were measured using an enzyme-linked immunosorbent assay. All four bacterial meningitis patients had M-CSF levels in the cerebrospinal fluid which exceeded 1540 U/ml, and the mean value was 3333 +/- 1481 U/ml. The mean M-CSF level in the cerebrospinal fluid of the ten aseptic meningitis patients was 393 +/- 175 U/ml, which was higher than that of patients who suffered from a disease other than meningitis (179 +/- 90 U/ml) (P < 0.01). There was no clear correlation between the M-CSF levels and the numbers of white blood cells, granulocytes, or monocytes in the cerebrospinal fluid. These elevated M-CSF levels were thought to be of a local origin, since most patients with high M-CSF levels in the cerebrospinal fluid had relatively low M-CSF levels in the serum.

Adult↗

Cytokine production by peripheral blood monocytes and T cells during haemopoietic recovery after intensive chemotherapy.

We studied the production of cytokines by peripheral blood monocytes and T cells during the period of haematological recovery following intensive chemotherapy. Twelve adults with haematological malignancies received consolidation chemotherapy of complete remission. Monocytes and T cells were collected during the phase of recovery from intensive chemotherapy, and were incubated for 24 h in a culture medium with 10% FCS. Concentrations of cytokines in the culture supernatant were measured with an enzyme-linked immunosorbent assay. During the recovery phase, concentrations of IL-6, G-CSF and IL-1 beta in the culture supernatant of the collected monocytes significantly exceeded those of the monocytes obtained from normal healthy subjects. Similarly, the concentrations of GM-CSF and IFN-gamma in the supernatant of recovery phase T cells significantly exceeded those of normal T cells. Plasma levels of these cytokines were also elevated. These data suggest that the monocytes and T cells may be activated in vivo to produce haemopoietic cytokines during haematological recovery, and that, during haematological recovery, the monocytes and T cells may be actively involved in the induction of haematopoiesis following the myelosuppression induced by chemotherapy.

Adolescent↗

Identification of a functional receptor for granulocyte colony-stimulating factor on platelets.

Since granulocyte colony-stimulating factor (G-CSF) is thought to be a granulocyte lineage-specific cytokine, G-CSF receptors on blood cells other than those of granulocyte or monocyte lineage have not been well investigated. We now report that G-CSF receptors are present on platelets. The expression of G-CSF receptors on platelets was demonstrated by flow cytometry and radioreceptor assay. The mean number of G-CSF-binding sites per cell was 41 and the binding affinity was high (Kd 300 pM), similar to the affinity observed on granulocytes. Cross-linking assay revealed that G-CSF receptors were present on a single subunit protein of approximately 150 kD on the platelets. To clarify whether or not G-CSF might produce some direct functional influence on platelet response, the effects on platelet aggregation were studied. Although G-CSF itself did not affect platelet aggregation in vitro, preincubation with G-CSF augmented a secondary aggregation of platelets induced by low concentrations of adenosine diphosphate (ADP). There was a dose-response relationship for this G-CSF activity at concentrations of up to 10 ng/ml. Furthermore, the augmented ADP-induced secondary aggregation of platelets on G-CSF receptors was completely abrogated in the presence of anti-G-CSF polyclonal antibodies. These results indicate that platelets possess functional G-CSF receptors.

Adenosine Diphosphate↗

T lymphoid/myeloid bilineal crisis in chronic myelogenous leukemia.

We describe 2 cases of "bilineal" crisis in chronic myelogenous leukemia (CML) with T cell and myeloid phenotypes. In both cases, morphocytochemically distinct myeloid and T lymphoid blast populations proliferated simultaneously in the phase of blastic crisis--myeloperoxidase (MPO)-positive, CD7+/CD33+ myeloblasts in the peripheral blood, and MPO-negative, periodic acid Schiff (PAS)-positive lymphoblasts in the lymph nodes. In each case, common karyotypes containing Ph1 translocation were demonstrated in both the peripheral blood and the lymph node samples. In Case 1, the lymph nodes were occupied by > 90% lymphoblasts, which were positive for CD2, cytoplasmic CD3 (cCD3), CD5 and CD7 and terminal deoxynucleotidyl transferase (TdT), but negative for myeloid antigens. Myeloblasts and T lymphoblasts showed an identical rearrangement of the bcr gene by Southern blotting analysis, although the clonal rearrangement of the T cell receptor (TcR)-delta gene was seen only in T lymphoblasts. In Case 2, simultaneous proliferation of myeloblasts and lymphoblasts was documented morphocytochemically in the lymph node, and a flow cytometric analysis revealed the coexistence of CD7+/CD33+ and CD7+/CD33- blast populations. Each blast population was enriched by antibody-conjugated immunomagnetic beads; the former was positive for MPO by 64% but negative for cCD3 and TdT, whereas the latter was positive for cCD3 and TdT but negative for MPO (< 1%). CD7+/CD33+ myeloblasts and CD7+/CD33- lymphoblasts showed an identical rearrangement of the bcr gene. Neither TcR-beta, TcR-gamma nor the TcR-delta gene was clonally rearranged in either population. These observations clearly indicate that T lymphoid and myeloid blasts share common Ph1-positive progenitors, and that Ph1-positive T lymphoid/myeloid progenitors are probably involved in the development of blastic transformation in some percentage of CML patients.

Adult↗

[The utility of endoscopic ultrasonography (EUS) in endoscopic mucosal resection of early gastric cancer].

The utility of EUS was evaluated in 27 patients with early gastric cancer undergoing endoscopic mucosal resection over the past 2 years. Accuracy of the assessment of depth of cancerous invasion was studied in 16 patients undergoing EUS before endoscopic mucosal resection. Patients showing no changes in the submucosal (sm) layer or below on EUS included 15 with mucosal (m) cancer and one with sm cancer showing very slight infiltration. Seven patients with m cancer, a negative stump, and no ulcer in the cancer focus at endoscopic mucosal resection, were followed up for more than 1 year after endoscopic mucosal resection. On EUS, four patients showed Ul-IIs changes resembling benign ulcers, two showed Ul-IIIs changes and two showed no changes in the sm layer or below. All patients were negative for cancer in follow up biopsies. No lymphadenopathy was observed. EUS was effective in diagnosing the depth of cancerous invasion in patients undergoing endoscopic mucosal resection and also in clarifying changes in the sm and deeper layers during follow up.

Aged↗

Prognostic differences of adenocarcinoma arising from the cardia and the upper third of the stomach.

Of 1,012 patients who underwent gastrectomy for carcinoma of the stomach from 1980 to 1990, 33 with adenocarcinoma arising from the gastroesophageal junction (group C) and 55 with adenocarcinoma of the upper third of the stomach (group U) were compared with regard to their clinicopathologic features. Twenty-five patients (76%) in group C and 49 patients (89%) in group U underwent curative resection. The 5-year survival rates following curative resection were 32 and 70 per cent, respectively (P < 0.001). The poor prognosis of group C was ascribed to a greater propensity for esophageal invasion and nodal involvement, as well as to more advanced disease at diagnosis. The rich lymphatic drainage around the cardia may account for the wide spread of such tumors. Most patients presented with an advanced disease, so earlier detection of carcinoma of the cardia is mandatory to improve the results of surgery. At operation, it is important to dissect all the involved lymph nodes from the mediastinum to the abdominal paraaortic nodes and to ensure a tumor-free esophageal margin.

Adenocarcinoma↗

[Examination of cholangiogram of obstructive jaundice using MRI--compared with PTC and ERCP].

PTC and ERCP are most often used in diagnosis of obstructive jaundice. We studied the possibility of clinical diagnosis using MRI in 33 cases of obstructive jaundice. A clinical diagnosis of malignant tumors could be given in 17 cases out of 20 (85%) using MRI if respiratory standstill was possible. An MRI cholangiogram was particularly effective in describing tearful parting bile ducts and was clearer than PTC in describing negative gallbladders. Choledochal stones could be diagnosed in 58% of cases, which was less than the rate for malignant tumors. MRI is not an invasive examination, can be used in diagnosis of obstructive jaundice, and helps in selecting treatment methods such as PTCD and ERBD.

Adult↗