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Biomedical subjects

H Masuda

Publications and source records attributed to H Masuda.

At least 523 records · Page 29Linked to original sources
PubMed1986

Flow loaded canine carotid artery. I. A morphometric study of microfilament bundles in endothelial cells.

To estimate microfilament bundles in the endothelial cells of flow loaded arteries quantitatively, blood flow change was produced in the common carotid arteries of eleven female beagle dogs (1-2 years of age, 8-10 kg) employing the arteriovenous shunt method between the common carotid artery and external jugular vein. After 1 week, the amount of microfilament bundles was measured with a point counting method on transmission electron microscopical photographs. In the arteries loaded by highly elevated blood flow, the average thickness of microfilament bundles increased over 0.1 mu m (non-operative control: 0.01-0.02 mu m) and the average longitudinal cut area of a microfilament bundle grew over 0.7 mu m2 (non-operative control: 0.2 mu m2). The number of bundles increased over 1.0 piece (non-operative control: 0.2 pieces) per unit length (mu m) in transverse section and increased over 0.5 pieces (non-operative control: 0.2 pieces) in longitudinal section. The average thickness of the bundles significantly correlated to the blood flow increase ratio (the ratio of the blood flow rate of the final measurement to that before anastomosis). We consider that the microfilament bundles are the structure developed to combat the wall shear stress induced by the elevated blood flow.

Actin Cytoskeleton↗
PubMed1986

Pathological study of sequelae of Kawasaki disease (MCLS). With special reference to the heart and coronary arterial lesions.

Unexpected sudden cardiac death among children with a history of Kawasaki disease has come to be reported in Japan. Death occurred between 2 months and 8 years after complete recovery from Kawasaki disease according to our study material. To study the lesions of Kawasaki disease sequelae we examined 61 cases of Kawasaki disease which came to autopsy. In 17 of these the deaths apparently to be due to sequelae of this disease, were characterized by cardiac insufficiency caused by ancient coronary aneurysm with organized thrombotic occlusion and superimposed acute ischemic myocardial degeneration and/or necrosis. The age of the lesions appears to correlate with the interval period between complete recovery from this disease and death. Six cases succumbed incidentally of other causes: one traffic accident, one hemophilus meningitis, one chronic myeloid leukemia, one neuroblastoma, one meningeal hemorrhage due to rupture of basilar arterial aneurysm, and one acute lymphatic leukemia. Even in these cases, definite sequelae of arteritis were detected. A surgically resected coronary aneurysm and a ventricular aneurysm were also examined. It was disclosed by mass physical check-up of school children that 0.1% had a history of Kawasaki disease, among which 5-6% showed cardiac and/or coronary abnormality including aneurysms. The high incidence of cardiac involvement in Kawasaki disease has been proved in this study and this kind of lesion has the possibility of resulting in unexpected cardiac death of children.

Arteritis↗
PubMed1986

Comparison of spindle elongation in vivo and in vitro in Stephanopyxis turris.

The spindle in dividing cells of the diatom Stephanopyxis turris contains three distinct classes of microtubules: central spindle microtubules, which slide over each other and grow during anaphase spindle elongation; kinetochore-attached microtubules, which are located on the outer surface of the central spindle; and peripheral microtubules, which fan out from the spindle poles in astral-like arrays. The poles are multilayered structures, which remain attached to the spindle after isolation. In vitro, after addition of ATP, central spindles elongate and the two half-spindles slide completely apart with a concurrent decrease in the extent and magnitude of the zone of microtubule overlap. Spindle elongation takes place in spindles whose chromatin has been removed by enzymic digestion and the extent of elongation in vitro is increased by the addition of neurotubulin. After ATP addition the arrays of interdigitating microtubules in the zone of overlap become disordered and selectively depolymerize from the overlap zone polewards. In some reactivated spindles an unusual structure, a striated fibre, can be seen running from the pole plates part of the way towards the spindle midzone. The fibre has no precedent in mitotic ultrastructure and its function is unclear. These results demonstrate that we can duplicate the essential elements of anaphase B in vitro and that this system will be useful for further studies of the molecular basis of spindle elongation.

Anaphase↗
PubMed1986

[Anti-inflammatory effect of THS-201, a new intra-articular steroid].

The effect of THS-201, a new intra-articular steroid, on inflammations was examined using acute, subacute and chronic experimental models, and the antiinflammatory action of THS-201 was compared with those of reference steroids such as triamcinolone acetonide (TA), methylprednisolone acetate (MPA), hydrocortisone acetate (HA) and halopredone (HP). Reference steroids, which were given s.c. or locally, dose-dependently inhibited carrageenin-induced foot-pad edema, sodium carboxymethyl cellulose-induced leukocyte migration, cotton pellet granuloma and carrageenin granuloma pouch in rats. Although the inhibitory effects of reference steroids on such inflammations were unrelated to their administration routes, the inhibitory potency decreased in the following order: TA greater than MPA greater than HA = HP. THS-201 even at a dose of 100 mg/kg had no inhibitory effects on such inflammations when given s.c. By contrast, THS-201 given locally had anti-inflammatory actions: the inhibitory potency of THS-201 in chronic models was higher than that of TA, but was lower in the acute models than that of HA. In antigen-induced arthritis in rabbits, the inhibition of swelling of inflamed joints by intra-articular injection of THS-201 (2 mg/joint) persisted more than 30 days, suggesting that the elimination of THS-201 from the injected site was very slow. In contrast to the finding of reference steroids, THS-201 showed no systemic adverse reactions in all experiments. The results, which are in agreement with the findings of labeled THS-201 into arthritic joints, indicate that THS-201 can strongly inhibit recurrence of inflammation as compared with reference steroids tested.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Topical↗
PubMed1986

[Clinical effect of allylestrenol on benign prostatic hypertrophy].

Allylestrenol at the daily dose of 50 mg was administered to 45 patients with benign prostatic hypertrophy. The treatment was performed for more than 12 weeks in 40 patients, and improvements, marked and moderate, were observed in 22 patients (55%) in the overall judgement. As side effects of this drug, decrease of potency was observed in 3 cases, decrease of libido in 1 case, pigmentation on breasts in 2 cases, palpitation in 2 cases, short breath in 1 case, and gastrointestinal symptoms in 1 case. However, these side effects were not serious. Our trial suggests that the treatment of benign prostatic hypertrophy with allylestrenol can be useful in urological clinics.

Aged↗
PubMed1986

Giant to small emphysematous bullae induced by Sephadex beads and carrageenan.

The effects of disturbances of the pulmonary circulation on the formation of pulmonary emphysematous bullae in rabbits were studied with the use of changes in the parenchyma of lungs insulted by both pulmonary embolization with Sephadex beads and carrageenan-induced pneumonia. Rabbits given one of the larger doses of Sephadex and then carrageenan in solution had giant bullous lesions in the lobe treated with those agents 2 months later. More animals had bullous lesions in the groups given the larger doses of Sephadex than in groups given the smallest dose or none. In animals killed after 2 weeks, bullous lesions were found, whereas there were none in those killed after 1 week. These results suggest that the size and number of bullous lesions forming in the treated lobes are associated with the dose of Sephadex. Giant and small bullous lesions are varieties of the same disorder, and there seems to be a latent period for development.

Animals↗
PubMed1986

[Combination chemotherapy and radiotherapy in small cell carcinoma of the lung].

Thirty-nine patients with small cell carcinoma of the lung were treated sequentially with induction chemotherapy, radiotherapy and then maintenance chemotherapy. Induction chemotherapy consisted of two regimens, cyclophosphamide, vincristine, methotrexate (COM) and adriamycin, ACNU, vindecine (ANV) given by randomization. Radiotherapy was given for patients with limited disease (LD) as a rule. After radiotherapy the drugs used for maintenance chemotherapy were alternated and reduced in dose. Eighteen patients were treated with a COM-ANV sequential combination and sixteen patients were treated with an ANV-COM combination. Thirteen patients had limited disease (LD) and eleven patients had extensive disease (ED). Of 12 patients with LD treated with COM-ANV therapy, 9 patients (75%) responded with 3 (25%) complete responses. Of 11 patients with LD treated with ANV-COM therapy, 9 patients (81.8%) responded to the therapy. According to disease extent, response rate was 82.6% for LD and 54.5% for ED. The median survival times were 9 months for patients with COM-ANV therapy and 12 months for those with ANV-COM therapy. Also, the median survival time was 15 months for LD patients and 5 months for ED patients. Major toxicities in ANV therapy were anorexia, nausea, and myelosuppression, and were more frequent than with COM therapy. These results showed no clear evidence of superiority in either the COM-AMV or ANV-COM regimen.

Adult↗
PubMed1986

[Randomized study of lentinan on patients with advanced gastric and colorectal cancer. Tohoku Lentinan Study Group].

A randomized study of mitomycin C (MMC)+5-FU [control group] vs MMC+5-FU+lentinan (LNT) [LNT group] was conducted in order to evaluate the effect of LNT against advanced gastric and colorectal cancers by the envelope method in 166 patients, comprising of 115 cases of gastric cancer and 51 cases of colorectal cancer. Significant increases were observed in the survival rates for the LNT group (p less than 0.05) for both patients with gastric and colorectal cancer. No significant difference was observed in response rates between the aforesaid two groups, though the response rate in the LNT group was slightly higher than the control group. These results suggest that LNT in combination with anticancer drugs prolong the survival time of patients with advanced gastric and colorectal cancer.

Adult↗
PubMed1986

Intratumoral injection of thymidine: enhancement of the antitumor activity and incorporation of 5-fluorouracil into tumor RNA in a murine tumor system.

Intratumoral injection of thymidine (dThd) into mice bearing an Ehrlich ascites solid tumor in combination with an ip injection of 5-fluorouracil (FUra) was performed to investigate the following: (a) whether intratumoral injection of dThd would increase both the incorporation of FUra into tumor RNA and the antitumor activity of FUra as effectively as ip injection of dThd, and (b) whether intratumoral injection of dThd would have a selective advantage for increasing the incorporation of FUra into the tumor RNA, relative to normal tissue RNA. Pulse-labeling with [3H]FUra at different times after dThd injection indicated that the most effective incorporation of FUra into the tumor RNA occurred with both intratumoral and ip injection of dThd, when FUra and dThd were given simultaneously. The amount of FUra-containing RNA [(FU)RNA] was dThd dose-dependent and reached a maximum at a dThd dose of 100 mg/kg, in the case of either intratumoral or ip injection. The maximal level with intratumoral injection of dThd was twofold higher than the level with ip injection and at least fivefold higher than the level achieved with FUra alone. In a time course study, the amount of (FU)RNA formed after intratumoral injection of dThd was comparable to the level obtained with ip injection, which was fourfold to sixfold greater than that seen with FUra alone. Furthermore, in the four normal organs (bone marrow, intestine, kidneys, and lungs) the amount of (FU)RNA formed after intratumoral injection of dThd was markedly lower than the level with ip injection. Assay of FUra degradation products revealed low levels of FUra catabolism in the tumor tissue compared to liver. In addition, therapy experiments showed that the antitumor activity of FUra was increased 17-fold by coadministration of dThd by either route.

Animals↗
PubMed1986

[In vitro chemosensitivity testing evaluated by intracellular ATP level: ATP assay].

In vitro chemosensitivity was evaluated by bioluminescence ATP assay in 12 human tumors including 7 gastric cancers and 5 colo-rectal cancers. Tumor fragments minced with scissors were exposed to 6 kinds of antitumor drugs: carboquone, adriamycin, aclacinomycin A, mitomycin C, cisplatin and 5-FU at peak plasma concentration or ten times peak plasma concentration. After 3 days at 37 degrees C, each tumor fragment suspension was washed with phosphate-buffered saline, boiled for 3 min and assayed for its intracellular ATP level using the luciferin-luciferase method. The ATP level of the drug-untreated group was 6.01 +/- 4.55 X 10(-10) moles/mg tissue protein in gastric cancers and 9.77 +/- 8.46 X 10(-10) moles/mg tissue protein in colo-rectal cancers. The percentages of cases in which the ATP level was reduced to less than 50% by the antitumor drugs were 70% for carboquone, 11% for adriamycin, 30% for aclacinomycin A, 45% for mitomycin C, 13% for cisplatin and 18% for 5-FU at peak plasma concentration, and 90% for carboquone, 78% for adriamycin, 80% for aclacinomycin A, 82% for mitomycin C, 63% for cisplatin and 82% for 5-FU at ten times peak plasma concentration. The test for chemosensitivity prediction is thus available at peak plasma concentration of antitumor drugs in ATP assay.

Adenosine Triphosphate↗
PubMed1986

[Intravesical chemotherapy of (2''R)-4'-O-tetrahydropyranyladriamycin in bladder tumor].

The effect of (2"R)-4'-0-tetrahydropyranyladriamycin (THP), a derivative of adriamycin (ADM) on bladder tumors was evaluated by intravesical instillation. Twenty-one patients with bladder tumors were treated with THP instillation into the bladder. THP (20-30 mg dissolved in 20-40 ml of distilled water) was instilled into the bladder daily for 3 consecutive days as a course. The patients received 2 to 5 courses in total. Of 21 patients, 4 showed complete disappearance of the bladder tumors, while partial response (50% tumor reduction) was observed in 6 cases. Therefore, the overall response rate was 48%. However, with regard to the 16 patients with superficial bladder tumors (Ta, T1) an overall response rate of 63% was noted. The main side effect of THP instillation was temporary bladder irritability, which was seen in 57% of all the patients. No cases revealed systemic side effects. The same antitumor effect was obtained at a lower concentration of THP in the intravesical chemotherapy, compared with that of ADM. It was concluded that THP is a useful drug for the intravesical chemotherapy of bladder tumors.

Aged↗
PubMed1986

[In vitro chemosensitivity of various human tumors evaluated by the succinate dehydrogenase inhibition (SDI) test (2)].

In vitro chemosensitivity was evaluated by succinate dehydrogenase inhibition (SDI) test in 94 human tumors including 59 gastric cancers, 27 colo-rectal cancers and 8 malignant lymphomas. Tumor fragments were exposed to 12 kinds of antitumor drugs at ten times peak plasma concentration. Evaluable rates were 86/94 (91%) for all cases, 56/59 (95%) for gastric cancers, 22/27 (81%) for colo-rectal cancers and 8/8 (100%) for malignant lymphomas. The mean of SD activity was decreased to 48% of that of control cells with aclacinomycin, 49% with carboquone, 53% with actinomycin D, 54% with mitomycin C and 54% with daunomycin for gastric cancers, 59% with adriamycin for colo-rectal cancers and 33% with cyclophosphamide (40487 S), and 33% with actinomycin D, 37% with vinblastine and 39% with adriamycin for malignant lymphomas. When the SD activity was reduced to below 50% by antitumor drugs, the chemosensitivity was defined as positive. The antitumor drugs which had a higher chemosensitive-positive rate were aclacinomycin, carboquone and mitomycin C for gastric cancers, adriamycin for colo-rectal cancers and 40487 S, daunomycin and vinblastine for malignant lymphomas. Our results suggest that the origin of a tumor is a critical factor in its chemosensitivity.

Antineoplastic Agents↗
PubMed1986

The intercostal artery in Kawasaki disease. A pathologic study of 17 autopsy cases.

Two hundred twenty-seven arteries from 17 autopsy patients having a history of Kawasaki disease were studied histopathologically and immunohistologically. Forty-five arteries in four cases (duration of illness ranging from 23 to 33 days) showed an arterial lesion characterized by reactive proliferative change of the medial smooth-muscle cells and frequent aneurysmal dilation. The lesion was mostly localized to the proximal portion. The intercostal arterial lesions were similar to those in the coronary arteries except for some delay in their occurrence. It is suggested that the proliferation of medial smooth-muscle cells after their degeneration is a key feature of the arterial lesion in Kawasaki disease.

Arteries↗
PubMed1986

[Advanced thyroid carcinoma--possible induction of the host's antitumor immunological response by 131I therapy].

UNLABELLED: The patient was a 76-year-old man. When he was 31, he had undergone right lobectomy for thyroid cancer. Following this, had repeated recurrences, and finally reached total-thyroidectomized status. Consequently, he was given thyroxin and PS-K thereafter. When he was 75, 131I therapy was undertaken for lung metastases. The changes of serum anti-microsomal antibody (AMA), immunosuppressive substance (ISS) and thyroglobulin (TG) were as follows: three months after the therapy, AMA was 40(2), although it had always been negative before. Nine months later, ISS and TG markedly decreased. CONCLUSION: Under the administration of immunomodulating agents, 131I therapy might induce antitumor immunological responses by the effect of enhancement of cancer cell antigenicity.

Aged↗