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Biomedical subjects

M Fukui

Publications and source records attributed to M Fukui.

At least 685 records · Page 38Linked to original sources
PubMed1982

Collateral sensitivity of 6-mercaptopurine-resistant sublines of P388 and L1210 leukemia to the new purine antagonists, 5-carbamoyl-1H-imidazol-4-yl piperonylate and 4-carbamoylimidazolium 5-olate.

Two new purine antagonists, 5-carbamoyl-1H-imidazol-4-yl piperonylate (SL-1250) and 4-carbamoylimidazolium 5-olate (SM-108), were investigated for their antitumor activities against 6-mercaptopurine (6-MP)-resistant sublines of P388 and L1210 leukemia. It was found that both resistant sublines exhibited collateral sensitivity instead of cross-resistance to these new antipurine drugs. Since more potent cytotoxic activities of these drugs against 6-MP-resistant cells were observed even in vivo cell culture systems, this collateral sensitivity was proved on a cellular basis. Biochemical studies revealed that 6-MP-resistant sublines of both P388 and L1210 leukemia are deficient in hypoxanthine-guanine phosphoribosyltransferase activity. In these cells, not only the activation of 6-MP to its nucleotide but also the synthesis of guanosine 5'-monophosphate via the salvage pathway seems to be severely restricted. However, SL-1250 and SM-108 can be activated to their nucleotide even in these 6-MP-resistant cells because the activation of these compounds is proceeded by adenine phosphoribosyltransferase. In conclusion, suppression of de novo purine synthesis with SL-1250 and SM-108 seems to be a very efficient means of killing these 6-MP-resistant cells, which lack a salvage pathway for guanosine 5'-monophosphate.

Animals↗
PubMed1982

Studies on viral respiratory disease in laboratory cats. I. Isolation of feline herpesvirus and choice of proper disinfectant.

In the laboratory cat colony consisted of 14 Korats and 8 Japanese native cats, the disease characterized by upper respiratory signs occurred. Seven cytopathogenic agents were isolated from the oropharyngeal swabs and necropsy materials of affected cats by means of inoculation to primary feline kidney cell cultures. One of the isolates (KS-1 strain) was identical with feline herpesvirus (FHV), and appeared to be a causal agent of the trouble. Properties of the KS-1 strain were in general agreement with the known strains of FHV. Serologic examination and clinical analysis suggested that Japanese native cats became carriers, re-excreted the virus and spread it to susceptible cats. Virucidal activities of several disinfectants against FHV, comparing with a feline calicivirus (FCV), were studied and the following conclusions reached: 1) Sodium hypochlorite, iodine complex, benzethonium chloride and chlorhexidine were effective against FHV at commonly used concentrations. 2) Among chemicals tested sodium hypochlorite was most effective against FCV and followed by iodine complex. 3) Benzethonium chloride and chlorhexidine had little efficacy against FCV at commonly used doses.

Animals↗
PubMed1982

Ventricular and subarachnoid seeding of intracranial tumors of neuroectodermal origin--a study of 26 consecutive autopsy cases with reference to focal ependymal defect.

In a series of 26 consecutive autopsy cases of intracranial tumors of neuroectodermal origin, tumor seeding on the ventricular surface and in the subarachnoid space was studied. Five cases of glioblastoma multiforme, six of malignant astrocytoma, six of medulloblastoma, one mixed glioblastoma-fibrosarcoma, one unclassified glioma, and one ependymoma showed ventricular and/or subarachnoid seeding of tumor. The incidence of tumor seeding in our series (76.9%) is much higher than in other series. This discrepancy is probably due to the inclusion of a large number of very small tumor metastases that may have been overlooked in other series. In all cases where metastases were observed the primary tumor extended into the cerebrospinal fluid (CSF). Tumor seeding via the cerebrospinal pathway was more frequently associated with malignant tumors. The distribution of tumor metastases correlated with CSF flow and with the site of focal ependymal defects, which were present in normal brains but occurred more frequently and widely in hydrocephalus.

Adolescent↗
PubMed1981

Neuroradiological manifestations of suprasellar pituitary adenomas, meningiomas and craniopharyngiomas.

The radiological manifestations of 16 pituitary adenomas, six meningiomas and 14 craniopharyngiomas were reviewed. The differential diagnosis of these tumors is possible with a few exceptions when skull radiography, CT, angiography and metrizamide cisternography are carefully evaluated. Prolonged injection angiography (PIA) is particularly important for demonstrating the contours of pituitary adenomas and meningiomas. Metrizamide cisternography is indicated when the tumor contours are obscure using PIA, or when the differential diagnosis is uncertain.

Adenoma↗
PubMed1981

Huge cystic craniopharyngioma with unusual extensions: a case report.

The findings on computed tomography (CT) of a huge cystic craniopharyngioma in a 3-year-old girl are described. The cyst occupied both anterior cranial fossae and a part of it extended to the region of the third ventricle which was displaced posteriorly. The tumor showed no contrast enhancement after the intravenous administration of contrast medium.

Carotid Arteries↗
PubMed1981

Primary intracranial sarcomas: radiological diagnosis with emphasis on arteriography.

The radiological manifestations of primary intracranial sarcomas may be non-specific and they vary widely according to their histological variations. Reticulum cell sarcomas, however, can be included in the differential diagnosis with a high degree of reliability when one observes a hypovascular mass with arterial encasement and deep medullary veins. Tumor vessels and tumor stains supplied by dilated feeding arteries suggest the possibility of a sarcoma of the brain or of the meninges in infants. Nine reticulum cell sarcomas, four undifferentiated sarcomas, and one fibrosarcoma are presented here with their radiological manifestations, especially on angiography.

Adolescent↗
PubMed1981

Glial fibrillary acidic protein in medulloblastoma.

Twenty-four cases of classical medulloblastoma and one case of desmoplastic medulloblastoma were examined for glial fibrillary acidic protein (GFAP) using the immunoperoxidase method to assess astrocytic differentiation. In 16 cases of classical medulloblastoma GFAP-positive cells were present in variable numbers. These cells were classified as three different types according to size and shape. The type 1 cell was morphologically identical to the ordinary tumor cell, with a hyperchromatic nucleus and a scanty cytoplasm. The type 2 cell had a fairly rich cytoplasm with short cytoplasmic processes. The type 3 cell was characterized by a relatively large nucleus with sparse chromatin and well-developed cytoplasmic processes, and was considered a reactive astrocyte. The type 1 and some of the type 2 cells seemed to be neoplastic, displaying astrocytic differentiation. The remaining type 2 cells may have been reactive astrocytes. In one case of desmoplastic medulloblastoma, the majority of GFAP-positive cells were arranged in "islands", and had delicate fibrillated processes. GFAP-positive cells were also observed outside these "islands", though they were less numerous. Most of them were regarded as type 3 cells, but some were type 2. This may be interpreted as meaning that the glial character of the tumor was expressed more within than outside these "islands".

Adolescent↗
PubMed1980

Angiographic diagnosis of acoustic neurinomas and meningiomas in the cerebellopontine angle--a reappraisal.

Forty-two acoustic neurinomas and seven meningiomas in the cerebellopontine angle were reviewed, and the radiological differential diagnosis of these tumors is discussed. Though enlarged internal auditory meati and characteristic CT findings were reasonably reliable indicators for the diagnosis of acoustic neurinomas, it was angiography which substantiated their correct diagnosis. An arcuate vein was frequently demonstrated with acoustic neurinomas, but never with meningiomas. Visualization of tangled veins seems to favor a diagnosis of acoustic neurinomas. Contrary to earlier reports, tumor stains were most frequently visualized using selective external carotid arteriography. The degree of tumor stains did not aid in differentiating acoustic neurinomas from meningiomas. The importance of using angiotomography, especially in the anteroposterior projection, and external carotid angiography during prolonged injections of large amounts of contrast media, is emphasized.

Basilar Artery↗