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Biomedical subjects

K Tabuchi

Publications and source records attributed to K Tabuchi.

At least 199 records · Page 11Linked to original sources
PubMed1981

Immunohistochemical demonstration of IgG in meningioma.

Twenty human meningiomas were examined for IgG and IgM by the direct immunofluorescence of immunoperoxidase methods, or both. IgG was conspicuously found in and around the blood vessels, whorls, and psammoma bodies. It was also clearly present on the cytoplasmic membranes of the tumour cells. On the other hand, IgM was seen only within the blood vessels. Significance of these findings is briefly discussed including possible humoral immune reactions in regard to whorl and psammoma body formation in meningioma.

Adult↗
PubMed1981

Evaluation of the drug-induced morphological differentiation of rat glioma cells (C-6) from the aspects of S-100 protein level and con A binding pattern.

The intracellular content of the nervous system specific protein S-100 began to increase with 4 days latency following the morphological differentiation of cultured rat glioma cells (C-6) with 1 mM dibutyryl cyclic AMP (dbcAMP), rising to approximately 10-fold over the control level at 15 days after the treatment. The concanavalin A (Con A) binding pattern on the external cell surface of C-6 cells exposed to dbcAMP appeared as a smooth layer of 40-60 nm thickness whereas that of control cells was irregularly thick and patchy. The correlation between morphological and biochemical changes of C-6 cells after dbcAMP treatment is discussed in relation to the mechanism controlling the differentiation of glioma cells.

Animals↗
PubMed1981

Occurrence of bovine dermatophilosis in the southernmost islands of Japan.

Such cutaneous symptoms as characteristic incrustation and alopecia were noticed in 25 calves of the indigenous Japanese Black breed grazing on subtropical islands in Japan over a period of April, 1978 to February, 1980. These islands were Ishigaki, Kuro, Yonaguni and Tarama belonging to the Sakishima Islands. Microbiological and pathological examination on three of these calves revealed that the calves were affected with dermatophilosis caused by Dermatophilus congolensis. The disease in these calves seemed to be the same as that reported previously in other countries, since it attacked young calves in a humid district with an abundant rainfall. It broke out first on Ishigaki Island and subsequently on the other islands in 3 years. Discussion was made on factors inducing these outbreaks.

Actinomycetales↗
PubMed1980

Chromosome analysis of a brain malignant lymphoma cell line.

Chromosome studies of a malignant lymphoma cell line derived from the brain were made by Q- and G-banding techniques. The modal number of chromosomes was 45. Complex structural rearrangements were present, but the 14q+ marker chromosome frequently seen in malignant lymphomas was not identified in the cell line. The main karyotype in cells analyzed was 45, X, -Y, del (2) (q21q23), t (3;?) (p25;?), t (p12;?), -8, 11q+, 18q+, +mar. Absence of the 14q+ may be explained by: firstly, clones which possessed 14q+ marker chromosome in brain tumor cells may have been selected out with increasing culture time and repeated passages; or secondly, the presence of the 14q+ marker chromosome depends on the type of lymphoma.

Adult↗
PubMed1980

Primary intracranial choriocarcinoma.

The authors report four cases of primary intracranial choriocarcinoma, all in young males. There tumors occurred in the pineal region and one in the lateral ventricle. Besides the signs of increased intracranial pressure and ophthalmological disorders, skin pigmentation or eruption was observed in three cases and precocious puberty in two cases. Angiography revealed tumor stain with irregular vessels in all cases. Enhanced computerized tomography scans in the last two cases demonstrated a round, lobulated lesion of high density, with relatively low density in the central portion. Hormonal study was carried out in three cases. In addition to high levels of human chorionic gonadotropin (HCG) in the urine and cerebrospinal fluid and/or of plasma luteinizing hormone (LH), LH in tumor tissue or medium obtained via cell cultures was also high in all three cases, suggesting inherent activity of HCG secretion by the tumor cells. The tumors were relatively demarcated from the surrounding brain. They were very hemorrhagic, and fresh hematoma was identified in the tumor in case. Good results were obtained in two cases treated with surgical removal followed by simultaneous chemotherapy and 60Co irradiation.

Adolescent↗
PubMed1979

Carcinoma arising in the wall of congenital bile duct cysts.

The incidence of carcinoma arising in the wall of the congenital bile duct cysts is much higher than previously assumed. The authors report 4 such cases of primary and secondary carcinomas and review their clinical features through the similar 59 cases in the literature. Of the 63 cases, the average age was much younger, at least several decades, compared with cases of extra-hepatic carcinoma without bile duct cysts. The female-male ratio was 2.5:1. Racial preponderance was also observed, namely, the majority were Japanese. Additionally, many patients previously received various internal drainage procedures, especially choledochocystoduodenostomy. As the treatment, primary excision of the extrahepatic bile duct cyst seems to give the best results because it can avoid ascending cholangitis and prevent development of carcinoma. However, carcinoma still can arise in the intrahepatic bile duct cyst, which cannot be removed at the present time.

Adenocarcinoma↗
PubMed1979

Chromosomal banding patterns produced by methyl green-pyronin staining after trypsin treatment.

A method is described for producing banding patterns with methyl green-pyronin (MGP) stain in chromosomes of fibrosarcoma cells. 1) The stain was made by mixing equal volumes of 2% aqueous pyronin G, 2% aqueous methyl green, distilled water, and 0.1 M acetate buffer (pH 5.7). 2) Treatment with colcemide and hypotonic KCl (0.075 M) was performed as usual. 3) Metaphase chromosomes were prepared using the flame-drying technique and treated with 0.25% trypsin at 37 C for 45 to 90 seconds. Before staining, the slides were rinsed in PBS, in distilled water, and then were dipped in 0.05 M acetate buffer. 4) Chromosomes were stained for more than 20 minutes, rinsed in distilled water, and hot-air dried. Satisfactory results were obtained in uncontracted metaphase chromosomes. MGP stain has the advantage of permitting much longer trypsin treatment and staining time than the trypsin-Giemsa method while providing satisfactory banding patterns.

Animals↗
PubMed1979

Electron microscopic features of a brain tumor induced in hamster by BK virus, a human papova virus.

In order to locate the target cells for malignant transformation by BK virus (a human papova virus) in hamster brain, electron microscopic observation of tumor originally induced in hamster brain by BK virus was performed. With light microscopy, the BK virus-induced tumor (Vn 17) bore a close resemblance to human malignant ependymoma. Under the electron microscope, numerous microvilli and few cilia were visible on the surface of the tumor cells. These tumor cells were joined to each other by desmosomes. Gap junctions were not observed. Multilayered cuboidal cells were observed around the lumen and blood vessels in the tumor. With regard to fine structure, three types of Vn 17 cells were recognized; ependymal like cells, tanycytes with prominent cell processes, and undifferentiated cells with few cytoplasmic organelles. There was no basal lamina between the ependymal cells and the connective tissue stroma. The Vn 17 cells showed some similarity to the ultrastructural features of the epemdymal cells of newborn rabbits, suggesting that the target cells for Vn 17 may be cells related to ependyma. Malignant transformation of the cells would be initiated in the early stages after BK virus inoculation into the brain of newborn hamsters.

Animals↗
PubMed1979

[Histopathological study on experimental cerebral infarction in rat (author's transl)].

An experimental model of cerebral infarction in rat brain was successfully established by means of the unilateral internal carotid injection of carbon microspheres. A histopathological investigation of the infarcted brain was performed. The results were as follow: 1. No cerebral infarction was made by the unilateral internal carotid ligation alone. 2. Focal cerebral edema was most marked at the white matter of the embolized hemisphere. 3. The edema was also conspicuous in the deep cerebral gray matter, especially in hippocampus. Degeneration and pyknosis of the neurons were observed at the same area. 4. Transudative hemorrhage in the focal cerebral edema was usually observed in the thalamus. 5. Edematous change in the cortical gray matter was not so marked as compared with the hippocampus and thalamus. 6. Carbon microsphere was not found in the capillaries of ipsilateral choroid plexus. The present experimental model of cerebral infarction will be useful in elucidating the pathological mechanisms of the cerebral infarction.

Animals↗
PubMed1978

Immunoelectron microscopic localization of s-100 protein in cultured rat glioma cells.

Immunoelectron microscopic localization of the nervous system specific protein S-100 in the cultured rat glioma cells was successfully conducted by an unique immunocytochemical technique using peroxidase-labeled antigen binding Fab' fragments. The intensely electron dense reaction product for S-100 protein was localized mainly at ribosome granules associated with endoplasmic reticulum membranes and at free ribosome granules. S-100 protein was also associated to some extent with the cytoplasmic and nuclear membranes. A positive reaction was localized at the nuclear pores as if it were being prevented from entering into the nucleus. No activity was found in the nucleoplasm except for a slightly positive reaction product associated with nucleolus. The possible role for S-100 protein in neural cells was discussed in relation to the nuclear acidic proteins involved in genomic regulation.

Animals↗
PubMed1978

Screening of human brain tumors for SV40-related T antigen.

A series of 39 human brain tumors has been screened for the presence or absence of SV40-related T antigen by the direct and indirect immunoperoxidase methods. Two tumors of ependymal origin (malignant ependymoma, choroid plexus papilloma) revealed markedly positive nuclear staining for T antigen both in vivo and in vitro. The relationship of these tumors to their experimental counterparts inducible by recent human papovavirus isolates is discussed.

Antigens, Viral↗
PubMed1978

Immunocytochemical evidence of SV 40-related T antigen in two human brain tumours of ependymal origin.

A series of thirty-time human brain tumours has been screened for the presence or absence of SV 40-related T antigen by the direct and indirect immunoperoxidase techniques. Two tumours (an ependymoma and a choroid plexus papilloma) of ependymal origin revealed markedly positive nuclear staining for T antigen both in in vivo and in vitro. The possible viral etiology of these human brain tumours is discussed in relation to recent human papovavirus isolates.

Animals↗