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Biomedical subjects

T Ogata

Publications and source records attributed to T Ogata.

At least 415 records · Page 23Linked to original sources

Ventriculo-coronary micro-communications in pulmonary atresia and sequential changes of coronary arteries.

In the present paper, numerous micro-communications between myocardial sinusoids and small branches of coronary arteries are studied which existed in a rudimentary right ventricle of a female neonate with pulmonary atresia and an intact ventricular septum, who was born on the 40th week of gestation. Cardioangiography revealed a large fistulous subepicardial communication. At autopsy, myocardium of the right ventricle appeared spongy with extensive sinusoid slits. In addition to the large communication which was connecting a deeply extending sinusoid of the right ventricle to the main trunk of the anterior descending artery, numerous micro-communications were found between myocardial sinusoids in the rudimentary right ventricle and intramural small branches of the coronary artery. Furthermore, morphometrical analysis demonstrated that the medias of the intramural arteries in both ventricles of the present case were significantly hypertrophic, as compared with those in the control cases without communications (p less than 0.05). These facts indicate the significance of hemodynamic factors on the persistence of embryonic sinusoid-coronary communication.

Angiocardiography↗

Effects of combined treatment with nimustine hydrochloride and radiation on solid FM3A tumor in mice.

Female C3H/HeN mice bearing solid FM3A tumors were treated with a combination of ACNU (or Nimustine hydrochloride) and radiation in order to investigate the antitumor effects and also to determine the optimal treatment schedule of ACNU in such combined therapy. ACNU was intravenously injected either twice with an interval of 2 weeks and a dose of 30 mg/kg (intermittent large-dose treatment), or as 4 weekly doses of 15 mg/kg (fractionated small-dose treatment). Local irradiation (5 Gy) at the tumor site was performed twice with an interval of 2 weeks between the doses. Synergistic effects were obtained by the combination of ACNU and radiotherapy in terms of tumor growth inhibition and prolongation of survival. Histology also revealed much greater reduction of viable tumor cells in the case of combination treatment. With either treatment with ACNU alone or in combination with irradiation, the intermittent large-dose injections resulted in better inhibition of tumor growth than did the fractionated small-dose injections, but the survival times with the intermittent treatments were not as prolonged as would be expected from the direct effects. Loss of body weight and depression of WBC number were also much more severe in the intermittent treatment group. Thus, it may be concluded that when ACNU is combined with radiotherapy, the intermittent large-dose regimen is not necessarily superior to the fractionated small-dose one.

Animals↗

Protective effect of nimustine hydrochloride against radiation-induced pulmonary injury in mice.

Female C3H/HeN mice were irradiated in the thorax at a dose ranging from 10 to 25 Gy with or without ACNU (nimustine hydrochloride) treatment in order to determine whether the chemotherapeutic agent would lead to an enhancement of radiation-induced lung damage. ACNU given intravenously at 15 mg/kg immediately prior to irradiation reduced the mortality of mice irradiated with a low dose; mortality with either radiation alone or radiation plus ACNU was 4/10 (40%) or 0/10 (0%) at 13.1 Gy, and 9/10 (90%) or 6/10 (60%) at 15 Gy, respectively. The presence of ACNU during thoracic irradiation also prolonged the survival time of mice approximately 2-fold over that of animals given radiation alone. Histological examination of mice sacrificed 80 days after treatments revealed that the combination of drug and irradiation produced no radiation pneumonitis, which was predominant in mice given radiation alone. It is unexpectedly concluded that ACNU may have a protective effect against radiation-induced lung injury.

Animals↗

Esophageal electrochemical burn by button-type alkaline batteries in dogs.

In this study, electrochemical burns of the esophagus from button-type alkaline batteries were demonstrated. A charged mercurial button-type battery was fixed in the esophagus of 11 dogs. After 2, 4, 8, 24, 48, or 72 hr, batteries and esophagus were removed and examined micro and macroscopically. In 3 dogs, a charged battery with double capsule and dummy battery were placed for 24 hr. At 8 hr after placement, the esophagus mucosa showed abrasion. The charged batteries produced superficial abrasion or necrosis under the muscular layer of the esophagus without any evidence of leakage of the battery content during 48 hr. Dummy batteries did not produce any pathological findings. This indicates that the corrosion was caused by flow of a direct 1.5 v current and not by outflow of the content or compression.

Animals↗

Tetrodotoxin secreting glands in the skin of puffer fishes.

Unique exocrine glands or gland-like structures were found in the skin of several species of puffer fishes of the genus Takifugu. The glands of T. pardalis and T. vermiculare porphyreum consisted only of secretory cells with a large vacuole. These cells were completely enclosed by epithelial cells with developed microfilaments, except at their opening to the lumen. The contents of the large vacuole in the peculiar secretory cell were forced out when the puffer was stimulated. Exocrine glands or gland-like structures with peculiar secretory cells were also found in the skin of T. poecilonotus, T. niphobles and T. vermiculare radiatum. A high concentration of TTX was detected in the gland contents collected directly from live specimens of T. pardalis. We therefore conclude that these glands are TTX secreting glands.

Animals↗

The toxic effect of diquat on the rat lung after intratracheal administration.

Diquat toxicity to the lung was evaluated in rats. Diquat was administered intratracheally (i.t.) and its toxic potential was compared with that of paraquat. Diquat showed toxic effects in the lung when administered i.t. In previous research, diquat administered by the intravenous (i.v.) or oral (p.o.) route had little effect on the lung. a sufficient dose of diquat administered i.t. would be potentially toxic to the lung, but diquat is much less toxic to the lung than paraquat, which is actively taken up by lung tissue. This suggests that diquat is not actively taken up by lung tissue when administered i.t., but may be passively taken up by the lung tissue and induce lung damage.

Animals↗

Two murine monoclonal antibodies against human lung cancer-associated antigens.

Two murine monoclonal antibodies, MAb 8 (immunoglobulin G3 kappa) and MAb 15 (immunoglobulin G1 kappa), were produced after immunization with TKB-2, a variant cell line of human small cell carcinoma of the lung. In enzyme-linked immunosorbent assay, these antibodies reacted with four major types of lung cancer cell lines and various extrapulmonary tumor cell lines. Immunohistological study, however, showed highly specific binding to lung cancers; MAb 8 bound to 68% of 65 lung cancers, and MAb 15 bound to 72% of them. Interestingly, both antibodies were more reactive with non-small cell than small cell lung cancers and bound most frequently to large cell carcinoma. Most extrapulmonary tumor tissues were negative in staining with a few exceptions; endodermal sinus tumor (two of two) was positive to both antibodies, breast carcinoma (one of five) to MAb 8, gastric carcinoma (one of three), and malignant melanoma (one of one) to MAb 15. Cross-reactions with normal tissues were limited; MAb 8 reacted with adult and fetal lung, and MAb 15 with esophagus and renal tubules. MAb 8 recognized a Mr 48,000 glycoprotein antigen (carbohydrates as its epitope), and MAb 15 recognized two proteins (Mr 85,000 and 45,000) (peptides as their epitopes). These two antibodies, detecting novel antigens extensively associated with and highly specific to lung cancers, are potentially useful for the study of lung cancer.

Animals↗

[Postoperative chemotherapy of pathological stage I non-small cell carcinoma of the lung].

Between August 1982 and February 1985, 13 patients with pathological stage I non-small cell lung cancer received postoperative chemotherapy with ACNU, ADM and 5-FU. Nine patients had squamous cell carcinoma, two adenocarcinoma, and two large cell carcinoma. All patients were alive in August, 1985, but four of them had recurrent disease. The site of recurrence was the brain in three and the contralateral lung in one. Of these four patients, three had t2n0(-) p0 squamous cell carcinoma and one t1n0(-) p1 large cell carcinoma. In a control group consisting of six squamous cell carcinoma and six adenocarcinoma, recurrence occurred in one patient with t1n0(-) p0 squamous cell carcinoma. Although the treated group had unfavorable conditions of cell type and tumor size, there was no evidence that this combination chemotherapy could control recurrence of the tumor under these conditions.

Adenocarcinoma↗

[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↗

[Systemic hyperdynamic circulation and serum hormone concentrations in portal hypertension].

In order to evaluate the pathogenesis of the systemic hyperdynamic circulation in portal hypertension, serum concentration of eight kinds of hormones including glucagon (Glu), aldosterone (Ald), renin (Ren), and epinephrine (Adr), and the hemodynamic parameters were measured in a series of 30 patients, of whom 23 were patients with liver cirrhosis, 3 were with Banti's disease, 2 with chronic active hepatitis, and 2 with pre-cirrhotic change. The average cardiac index was 4.6l/min, m2, with normal PCWP of 6.7 mmHg. CI. and SVR. showed significant inverse correlation of r = -0.767 (p less than 0.01), however, PCWP and CI did not have any significant correlation. Average serum concentrations of Glu, Ald, and Ren were 160 pg/ml, 139 pg/ml, and 5.4 ng/ml, respectively, all of which were increased up to 2.5 times above the normal values. Adr, norepinephrine, cortisol, estrone and estradiol were within normal limits. Of the eight hormones being measured, only Glu had significant correlation with both liver function tests and the cardiac index (r = 0.479, p less than 0.05). Neither Ald nor Adr had significant correlation with hemodynamic parameters.

Adult↗