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Y Hiramoto

Publications and source records attributed to Y Hiramoto.

At least 55 records · Page 3Linked to original sources

Synergistic effect of K-18 and concomitant hyperthermia for treatment of Lewis lung carcinoma in mice.

We investigated the synergistic anti-tumor effects of K-18 (conjugate of human gamma-globulin and melphalan) and concomitantly administered hyperthermia on Lewis lung carcinoma in mice. The antitumor effect of a subeffective dose of K-18 or an equivalent dose of melphalan alone was enhanced by local hyperthermia. K-18 administration demonstrated a greater potentiation for inhibition of tumor growth than that of melphalan alone. Local hyperthermia plus K-18 reduced the dose of melphalan required for tumor growth inhibition by melphalan alone. The combined application of K-18 and hyperthermia for treating cancer warrants further study.

Animals↗

Serum CEA levels facilitate detection of recurrences of cancer in patients after gastrectomy.

In an attempt to assess the usefulness of carcinoembryonic antigen (CEA) for predicting the progression of gastric cancer, CEA productivity was evaluated according to serum CEA levels, at the time of recurrence or relapse. In cases of a recurrence, abnormal CEA levels were observed in 14 of 17 (82.4 per cent) with differentiated carcinoma and in 9 of 21 (42.9 per cent) with undifferentiated carcinoma. Preoperative abnormal CEA levels were observed in only 6 of 41 patients (14.6 per cent). A median lead time of manifestation of recurrence was 5 months. In those with relapse, 9 of 11 (81.8 per cent) patients with differentiated carcinoma and 13 of 18 (72.2 per cent) with an undifferentiated carcinoma had abnormal CEA levels. Preoperative abnormal CEA levels were observed in 24 of these 89 patients (27.0 per cent). Postoperative monitoring of CEA seems to be useful for early recognition of gastric cancer progression, irrespective of the preoperative CEA levels.

Adenocarcinoma↗

Distribution of fluorescently labeled tubulin injected into sand dollar eggs from fertilization through cleavage.

Porcine brain tubulin labeled with fluorescein isothiocyanate (FITC) was able to polymerize by itself and co-polymerize with tubulin purified from starfish sperm flagella. When we injected the FITC-labeled tubulin into unfertilized eggs of the sand dollar, Clypeaster japonicus, and the eggs were then fertilized, the labeled tubulin was incorporated into the sperm aster. When injected into fertilized eggs at streak stage, the tubulin was quickly incorporated into each central region of growing asters. It was clearly visualized that the labeled tubulin, upon reaching metaphase, accumulated in the mitotic apparatus and later disappeared over the cytoplasm during interphase. The accumulation of the fluorescence in the mitotic apparatus was observed repeatedly at successive cleavage. After lysis of the fertilized eggs with a microtubule-stabilizing solution, fluorescent fibrous structures around the nucleus and those of the sperm aster and the mitotic apparatus were preserved and coincided with the fibrous structures observed by polarization and differential interference microscopy. We found the FITC-labeled tubulin to be incorporated into the entire mitotic apparatus within 20-30 s when injected into the eggs at metaphase or anaphase. This rapid incorporation of the labeled tubulin into the mitotic apparatus suggests that the equilibrium between mitotic microtubules and tubulin is attained very rapidly in the living eggs. Axonemal tubulin purified from starfish sperm flagella and labeled with FITC was also incorporated into microtubular structures in the same fashion as the FITC-labeled brain tubulin. These results suggest that even FITC-labeled heterogeneous tubulins undergo spatial and stage-specific regulation of assembly-disassembly in the same manner as does sand dollar egg tubulin.

Animals↗

Organelle motility in rat pituitary clonal cells. I. Dynamic movements of intracellular organelles.

Intracellular organelle motion within clonal pituitary tumor cells (GH3) was observed directly with a contrast enhancement, computer-video microscope system. All particles except nuclei moved in a complex fashion. Two types of particles predominated; one large and round, the other small and elongated. We classified the movements of these particles as saltation, oscillation and slow translocation. Saltation was directional movement with velocity of the order of 1 micron/sec. Oscillation was local motion occurring within 1 micron that showed no specific direction. Its velocity was similar to that of saltation. Large particles, in particular, showed the 3rd type of movement, slow translocation. The velocity appeared to be one order slower than that of saltation. We also examined the cells with fluorescent, dark-field and electron microscopies. We concluded that the large round particles were lysosomes and the small elongated ones mitochondria. The microtubule depolymerizer, vinblastine and the microfilament depolymerizer, cytochalasin D, completely inhibited all the types of organelle movement. The mechanism and significance of these organelle movements are discussed.

Animals↗

Cleavage in a saponin model of the sea urchin egg.

A cell model, in which cleavage could be induced, was obtained from fertilized sea urchin eggs by putting eggs that were in the first cleavage into a solution containing 3 X 10(-5) g/ml saponin and suitable amounts of ATP and Ca2+. The cell membrane became freely permeable to ATP and Ca2+ within 1 minute. The respective optimal concentrations of ATP and Ca2+ that advanced the cleavage furrow in this model were 2 mM and 10(-8) M. With the optimal ATP and Ca2+ concentrations, the cleavage furrow of the model advanced at a rate that differed little from that in living eggs. The cleavage furrow soon receded, however, when the concentration of ATP was decreased to less than 1 mM or increased to more than 3 mM, as well as when the concentration of Ca2+ was increased to more than 10(-7) M.

Adenosine Triphosphate↗

[Phase II study of (2''R)-4'-0-tetrahydropyranyladriamycin (THP) in gastrointestinal cancer].

A phase II study of a new anthracycline, (2''R)-4'-0-tetrahydropyranyladriamycin (THP) was performed on 37 patients with gastrointestinal cancer in 6 co-operative study institutions. Twenty-five patients out of 37 were evaluable for response according to the Koyama-Saito's criteria. THP was administered weekly at doses of 10 to 30 mg/body or every 3 to 4 weeks at doses of 40 to 60 mg/body intravenously. Of the 14 patients with gastric cancer, we obtained one complete response and 3 partial responses (response rate 28.6%), and of the 6 patients with rectal cancer, we obtained one partial response (16.7%). Leukopenia of less than 3 X 10(3)/mm3 and erythrocytopenia of less than 300 X 10(4)/mm3 were seen in 48% and 26% of cases. Neither cardiotoxicity nor hair loss were seen. These results suggest that THP is useful in the treatment of patients with gastrointestinal cancer.

Adult↗

[The inhibitory effect of peptic ulceration on the growth of early gastric cancer].

The correlation between the growth pattern and peptic ulceration occurring in the cancer lesion was studied in early gastric cancer. Although the superficially spreading type (Super), which grows slowly, showed a high rate of being accompanied by peptic ulceration (74.0%), the deeply penetrating type (Pen), with rapid growth, had a lower such rate (Pen A- expansive type 9.7%; Pen B- infiltrative type 16.1%). Deep ulceration accompanied 32% of the Super cases, 12% of the small mucosal cases and no cases of the Pen type. The Super and small mucosal types located at the intermediate gland area had peptic ulceration more frequently than those at the other areas. The rate of the cases of peptic ulceration of undifferentiated adenocarcinoma was high in the Super and small mucosal types, and that of differentiated adenocarcinoma was 64.0% in the Super and only 33.3% in the small mucosal type. This study clarified that the growth of early gastric cancer was inhibitively influenced by peptic ulceration, which was modified by the localization and histologic type of the carcinoma.

Adenocarcinoma↗

[Evaluation of splenectomy in total gastrectomy for gastric cancer].

It has been well accepted that extensive prophylactic lymphadenectomy is certainly effective for elevating cure rate after gastric cancer surgery, however, regarding to the prophylactic splenectomy the arguments are controversial. We studied the value of splenectomy in total gastrectomy for gastric cancer by examining the late survival rates, the accuracy of intraoperative judgement of splenic hilar lymph node metastasis and postoperative changes of serum immunosuppressive factors. In curatively resected stage III cases without splenic hilar lymph node metastasis, the nonsplenectomized group showed a significant better late survival rate than the splenectomized group, 5-year survival rate being 59.9% in the former and 30.8% in the latter. In cases with splenic hilar lymph node metastases, 2 of 9 splenectomized patients survived more than 10 years. In cases of noncuratively resection, splenectomy did not enhance the survival rate. Although further clinical randomized study is needed to draw a definitive conclusion, we had better take a splenic reserve operation for the patients without splenic hilar lymph node metastasis. On the other hand, splenectomy should be performed in cases with splenic hilar lymph node metastases.

Gastrectomy↗

Bidirectional effects of splenectomy on the growth of syngeneic tumor in mice.

The effects of splenectomy on tumor growth following inoculation with a relatively large number of cells (1 X 10(7) ) and a smaller number of cells (5 X 10(5) ) of Meth I tumor were studied. When 1 X 10(7) tumor cells were inoculated, tumor growth in splenectomized mice was depressed, while tumor in sham-operated mice grew progressively. On the contrary, when 5 X 10(5) tumor cells were inoculated, the tumor take was lower in sham-operated than in splenectomized mice. The spleen cells from mice inoculated with either a large or small number of tumor cells, showed an equally potent cytotoxic activity, but no detectable suppressor cell activity. On the other hand, the activity of immunosuppressive factor was detected in sera from mice inoculated with 1 X 10(7) tumor cells, but not in those given 5 X 10(5) cells. The effect of splenectomy on tumor growth is, thus, bidirectional, depending on the dose of tumor cells inoculated.

Animals↗

Micromanipulation.

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Biomechanical Phenomena↗

[Anatomical quantification of the tibial part of the plantar aponeurosis].

The metrical analysis of the anatomical characteristics is important because of its objectiveness. As it is concerned with the organs belonging to the locomotor system, the metrical method of the bones has already been systematized by Martin (1928), whereas the same kind of method for use on other organs remains undeveloped. The author aims to establish the metrical method of the plantar aponeurosis. The method for measuring the tibial part of the aponeurosis developed in this paper is sufficiently applicable for obtaining its principal anatomical characteristics. The results show that the tibial portion of the plantar aponeurosis becomes statistically significantly wider and thinner in its anterior part, and that the thickness of the tibial portion of the aponeurosis in the anterior part is larger on the right side than on the left side.

Adult↗

[Variation of the fibular part of the plantar aponeurosis among present-day Japanese].

The plantar aponeurosis consists of the tibial and fibular parts. It is already known that the form of the fibular part markedly varies according to individuals. However, there have been few anatomical observations on this variation and none have statistically analysed it. This paper is concerned with the variation of the fibular part of the aponeurosis. Observations were carried out by dissecting thirty-nine present-day Japanese cadavers. The variations observed were classified into four types according to the Loth's method. It was clarified by means of the Chi-square test that the percentage of the medial fibre bundle is significantly higher in present-day Japanese than in Europeans, that is up to 20.5%. It was also found that the top portion of the medial fibre bundle, if it exists, is the origin of a part of the transverse head of the adductor pollicis muscle and the flexor digiti minimi brevis muscle in some cases.

Adult↗

Combination chemotherapy enhances survival of patients with unresectable gastric cancer.

Of 177 Japanese patients with a gastric cancer which could not be resected and seen at our institution during the period from 1964 to 1979, 153 were investigated with regard to the efficacy of anticancer agents, in terms of prolongation of life. The average survival time was 23 weeks in the combination chemotherapy group (57 cases), 17 weeks in the single drug chemotherapy group (42 cases) and 13 weeks in no chemotherapy group (54 cases). Three and 6 month survival rates in the overall patients were 57.1 per cent and 16.7 per cent for single drug chemotherapy group, and 37.0 per cent and 11.1 per cent for no chemotherapy group, while in the combination chemotherapy group, the rates were higher at 64.9 per cent and 29.8 per cent, respectively (combination chemotherapy vs. no chemotherapy group, p less than 0.05). In patients with peritoneal dissemination, hepatic metastasis and carcinomatous ascites, there was a significant difference in survival rates between those prescribed combination chemotherapy and those given no chemotherapy (p less than 0.05). Of 57 in the combination chemotherapy group, 6 and 9 month survival rates were 45.5 per cent and 22.7 per cent in the postoperative long-term cancer chemotherapy (PLCC) group (22 cases), such being higher than other combination chemotherapy group (35 cases), 22.9 per cent and 11.4 per cent, respectively. There was a significant difference in the survival rates between the two groups (p less than 0.05).

Adult↗

[Adjuvant chemotherapy for aged patients with gastric carcinoma].

The effectiveness of postoperative adjuvant chemotherapy on aged patients (more than 70 years old) with resectable gastric carcinoma was examined in our Department. Of the 178 patients, 75 patients received the drugs on various regimen and 103 patients had no chemotherapy a control group). No significant difference was noted in patient characteristics of age, sex and curability. In advanced gastric carcinoma such as stage III and IV, a significant increase in long-term survival after surgery was obtained with combination chemotherapy or immunochemotherapy compared with the control group (P less than 0.05). On the other hand, there was no significant difference in a survival rate of the patients with stage I and II.

Aged↗