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Biomedical subjects

K Isono

Publications and source records attributed to K Isono.

At least 325 records · Page 18Linked to original sources
PubMed1990

Etoposide protects mice from radiation-induced bone marrow death.

Etoposide is known to inhibit the activity of topoisomerase II, and to possess radiosensitizing effects. In this paper we show that pretreatment of mice with etoposide one day before whole-body irradiation had a protective effect against radiation-induced bone marrow death. The LD50/30 of mice given radiation alone was 8.26 Gy while that of mice given etoposide one day before whole-body irradiation was 10.35 Gy. The number of endogenous colony-forming units surviving in whole body-irradiated mice was significantly increased by pretreatment with etoposide.

Animals↗
PubMed1990

Hepatocellular carcinoma presenting well differentiated, normotrabecular patterns in peripheral or metastatic loci. Analysis of 103 resected cases.

In a series of 103 surgically resected hepatocellular carcinomas (HCCs), the tumor boundaries were rather clearly defined in 85 cases (82.5%). Twelve tumors had an ill-defined margin because adjacent pseudolobules were replaced by HCC with a well differentiated growth pattern (group A1). This peripheral pattern was unrelated to the predominant histologic type of the major tumor nodules. Despite its close resemblance to normal hepatic parenchyma, we were able to determine the area of the normotrabecular HCC on the basis of, differences in stain-ability, variable nuclear crowding and frequent microacinar formation. Moreover, scattered occurrence of nuclear atypia and midtrabecular conversion were also observed within the normotrabecular HCC. In an additional 6 cases, a band-like zone of normotrabecular HCC was evident peripherally around the primary lesion (group A2). Fourteen other cases (13.6%) had intrahepatic metastatic lesions formed either within the portal vein or in pseudolobules. Of these, 5 cases showed intrapseudolobular metastases with a normotrabecular pattern (group B). For precise evaluation of surgical HCC specimens, it seems to be particularly important to realize that HCCs sometimes have a highly differentiated appearance in a locus of peripheral invasion as well as intrahepatic metastasis.

Carcinoma, Hepatocellular↗
PubMed1990

Effect of unilateral pulmonary vagotomy on respiratory control in man.

We studied the breathing pattern and pulmonary function at rest, and ventilatory responses to progressive hypoxia and hypercapnia in 7 awake patients who had undergone esophageal-carcinoma resection with sectioning of the right pulmonary vagal branch by lymphadenectomy. Twelve control patients, who had received the same surgery without vagotomy, were also studied by the same protocol. Two months after the operation, both patient groups demonstrated substantial depressions in FVC and FEV1.0, and slight augmentations in breathing frequency, minute ventilation, and occlusion pressure at 0.2s (P0.2) at rest. In the vagotomized group, the occlusion pressure responses to hypercapnia (delta P0.2/delta PaCO2) and hypoxia (delta P0.2/delta SaO2) in terms of response curve slope increased from 1.3 +/- 1.2 to 1.9 +/- 1.1 cm H2O/Torr and from 0.29 +/- 0.19 to 0.88 +/- 0.53 cm H2O/% (p less than 0.05), respectively. Contrary to the vagotomized patients, the nonvagotomized control group exhibited no significant changes in ventilatory chemosensitivities. Furthermore, when comparing the control and vagotomized groups, postoperative ventilatory chemosensitivity responses in terms of both hypercapnic and hypoxic occlusion pressure responses were significantly higher in the latter. We suggest that (1) due to the development of the substantial mechanical limitation in pulmonary functions, the Hering-Breuer inflation reflex became activated after surgery, and (2) a diminished Hering-Breuer reflex effect to inhibit the respiratory centers by unilateral vagotomy may have resulted in augmented ventilatory chemosensitivities.

Carbon Dioxide↗
PubMed1990

[Manometric study of vertical banded gastroplasty for morbid obesity].

Morbidly obese patients undergoing vertical banded gastroplasty were studied preoperatively and/or postoperatively to characterize its manometric pattern. The esophageal manometry using station pull through technique involved 14 preoperative patients with a mean age of 28 +/- 7 years who were a obesity index of 220 +/- 32% and 14 postoperative patients with a mean age of 30 +/- 7 years who were a obesity index of 158 +/- 23%. Preoperative lower esophageal sphincter (LES) pressure using gastric base line as O was 16.1 +/- 8.5 cmH2O and a LES length of 3.4 +/- 0.9 cm. Postoperatively, the vertical banded gastroplasty channel had a pressure of 17.7 +/- 7.1 cmH2O and a length of 8.2 +/- 1.7 cm which was higher than gastric base line. No difference was seen between preoperative LES pressure and postoperative channel pressure, however postoperative channel length was significantly (p less than 0.01) larger than preoperative LES length. We concluded that vertical banded gastroplasty for morbid obesity created a longer high pressure zone in accordance with channel which would inhibit reflux of gastric juice.

Adult↗
PubMed1990

A new inhibitor of protein kinase C, RK-286C (4'-demethylamino-4'-hydroxystaurosporine). I. Screening, taxonomy, fermentation and biological activity.

In the course of our screening program using a bleb-forming assay, a new inhibitor of protein kinase C (PKC) was found in the fermentation of a streptomycete. The inhibitor, RK-286C (4'-demethylamino-4'-hydroxystaurosporine), inhibited the morphological change of K562 cells, a human chronic erythroleukemia cell, induced by phorbol 12,13-dibutylate at the concentration of 3 microM. The same concentration of the compound inhibited the activity of PKC in vitro and the aggregation of rabbit platelets induced by collagen and arachidonic acid.

Alkaloids↗
PubMed1990

The structure of tautomycin, a dialkylmaleic anhydride antibiotic.

The chemical structure of tautomycin (C41H66O13) was determined by chemical degradation, spectroscopic analysis and 2D INADEQUATE of tautomycin labeled with [1,2-13C]acetate. Tautomycin exists in methanol-buffer solution (1% diethylamine-formic acid, pH 7.3) as an equilibrium mixture of a 2,3-dialkylmaleic anhydride and its dicarboxylic acid in a ratio of approximately 5:4.

Acetylation↗
PubMed1990

The structure of tautomycetin, a dialkylmaleic anhydride antibiotic.

The chemical structure of tautomycetin (C33H50O10) was determined by chemical degradation and spectroscopic evidence. Tautomycetin exists in methanol-buffer solution (1% diethylamine-formic acid, pH 7.3) as an equilibrium mixture of a 2,3-dialkylmaleic anhydride and its dicarboxylic acid. The structure of tautomycetin is similar to tautomycin in many respects.

Acetylation↗
PubMed1990

New pyrrolobenzodiazepine antibiotics, RK-1441A and B. II. Isolation and structure.

Antibacteriophage antibiotics, RK-1441A and B, related to neothramycin were isolated from the culture broth of Streptomyces sp. and their structures were deduced from spectroscopic analyses. The structure of RK-1441A was 8,11-dihydroxy-3,7-dimethoxy-5-oxo-1H-pyrrolo[2,1-c:1,4]benzodiazepine. RK-1441B is a tautomeric mixture at C-3 of the structure, 3,8,11-trihydroxy-7-methoxy-5-oxo-1H-pyrrolo[2,1-c:1,4]benzodiazepine.

Anti-Bacterial Agents↗
PubMed1990

New pyrrolobenzodiazepine antibiotics, RK-1441A and B. I. Biological properties.

Streptomyces griseus and bacteriophage B were used for an assay system detecting anti-bacteriophage antibiotics. Streptomyces sp. RK-1441 was found to produce antibacteriophage antibiotics, RK-1441A and B, which are pyrrolo[1,4]benzodiazepine group antibiotics related to neothramycin. Both RK-1441A and B had antibacteriophage activity. The former showed antimicrobial activity on a hypersensitive strain of E. coli for antitumor antibiotics, but the later did not show the activity. Restriction enzyme assay suggested that RK-1441A formed adducts with guanine residues in DNA strands. RK-1441B was not active in vitro, but it might be converted to the active form in host organisms.

Anti-Bacterial Agents↗
PubMed1990

[Frequency of psychiatric patients visiting non-psychiatrist's outpatient clinic and its correlates].

To examine the frequency of psychiatric patients who visit outpatient clinic of non-psychiatrists in Japan, a mailed questionnaire survey was conducted of 200 non-psychiatrists randomly selected from the 703 registered members of the Kawasaki-city Medical Association, Kanagawa prefecture. Responses from 124 or 62% were received and data for 112 male respondents were analyzed. 1) The median number of psychiatric patients treated per month by respondents was 4, and the median proportion of the total outpatients that were psychiatric patients was 0.7%. 2) Sixty-one internists saw significantly greater numbers and proportions of psychiatric patients than the other 51 doctors. 3) The internists saw a higher proportion of mild anxiety, depression, alcohol-drug dependency and psychosomatic problems among all psychiatric patients than did other doctors. 4) For the internists a significant inverse correlation was observed between the total number of outpatients and the proportion of psychiatric patients. This was the result of a group of physicians who saw a relatively small number of outpatients but had a higher proportion of psychiatric patients among outpatients.

Adult↗
PubMed1990

[A case of fatal graft-versus-host disease following blood transfusion in esophageal cancer documented by homozygous changes of HLA typing].

A 72 year-old Japanese male with esophageal cancer underwent esophagectomy. After seemingly uneventful recovery, he developed high fever on 11 post-operative day (POD), rashes over the whole body on 13 POD and leukopenia on 15 POD. On 22 POD, thrombopenia and parenchymal bleeding of lungs were noted. He died on 26 POD after progressive hypoxia and hypotension. HLA type of peripheral lymphocytes on him changed homozygously to that of the transfused fresh blood. Skin biopsy showed mild leukocyte infiltration in the epidermis and the dyskeratotic keratinocytes were associated with a contiguous lymphocyte, the so-called satellite cell necrosis. In the findings of autopsy, aplastic bone marrow and atrophied spleen, whose weight was 14g, were noted. Based on the clinical picture, skin biopsy and HLA study findings, we diagnosed this case as post-transfusion GVHD. We think that high age, operative injury and preoperative irradiation might be inducement to reveal post-transfusion GVHD in this case.

Aged↗
PubMed1990

[A comparison of gastric bypass and vertical banded gastroplasty for morbid obesity].

We evaluated the effects of gastric bypass (GB) and vertical banded gastroplasty (VBG) for morbid obesity. Among 44 cases of obesity, 10 cases were treated with GB and 34 cases were treated with VBG. The obesity index in GB group was 199 +/- 20% preoperatively, and decreased to 136 +/- 15% at six months, 130 +/- 13% at one year, 131 +/- 14% at three years and 136 +/- 19% at five years postoperatively. On the other hand, the preoperative obesity index 212 +/- 26% in VBG group decreased to 149 +/- 17% at six months, 143 +/- 19% at one year and 144 +/- 18% at three years postoperatively. Obesity index was significantly smaller in GB group within 2 years following surgery, however no difference was seen in weight reduction. Obesity-related complications were markedly relieved postoperatively in both groups in accordance with weight reduction. The results demonstrate that GB and VBG are equally effective to reduce excess weight as well as complications of morbid obesity.

Adult↗
PubMed1990

[Effect of high dose etoposide, adriamycin, cisplatin (EAP) therapy with autologous bone marrow transplantation in gastric cancer].

A clinical usefulness of high dose EAP therapy with autologous bone marrow transplantation for gastric cancer was investigated. Three patients with advanced gastric cancer (one recurrent and 2 inoperable) with measurable lesions were treated with high dose EAP therapy consisting of VP-16 1200 mg/m2, ADM 80 mg/m2 and CDDP 80-120 mg/m2, and then 1 x 10(7)/kg of cryopreserved autologous bone marrow cells were transfused intravenously. All patients were recovered from aplastic period without any severe complications. Measurable lesions, namely, stenosis of prepyloris lesion, lymph node metastasis and invasion into pancreas in 3 patients with gastric cancer were reduced or diminished. It seemed that high dose EAP therapy with autologous bone marrow transplantation was safe and an useful strategy, especially for advanced gastric cancer.

Adult↗