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Biomedical subjects

Y Ohtsuki

Publications and source records attributed to Y Ohtsuki.

At least 343 records · Page 19Linked to original sources
PubMed1982

Detection of type C virus particles in Japanese monkeys seropositive to adult T-cell leukemia-associated antigens.

Type C virus particles which were identical to adult T-cell leukemia virus (ATLV) in morphology were detected in phytohemagglutinin-stimulated peripheral lymphocytes from four out of four Japanese monkeys seropositive to adult T-cell leukemia-associated antigens. It is possible that non-human primates may be a natural reservoir of ATLV, and vector-borne transmission of ATLV from monkeys to humans should be explored.

Animals↗
PubMed1979

Virus particles in normal prostate tissues of mice from ten strains, with special reference to type-B virus particles.

Prostate tissues of a total of 61 normal mice from 10 different strains, including high (C3H/Dm, RIII/Dm, and A/Dm) and low (BALB/c/Dm, C3Hf/Bi/Dm, and C3Hf/He/TEX) mammary cancer, and high (AKR/Dm) and low (CBA/J/Cr, SJL/J/Cr, and C57/BL/6/TEX) leukemia strains were examined by electron microscopy for the presence of virus particles. These studies demonstrated that type-B virus particles were present in normal prostate tissues of some old mice from all the three high (C3H/Dm, RIII/Dm, and A/Dm) and one low (BALB/c/Dm) mammary cancer strains. They further demonstrated that varying number of type-C virus particles were present in prostate tissues of some young and old mice, including those from all the 10 strains, especially in a larger number in older mice, and that intracisternal type-A virus particles were observed in all the mice examined. Immunological characterization of type-B virus particles by fixed immunofluorescence tests and immunoelectron microscopy revealed that type-B virus particles in normal prostate tissues of old C3H/Dm and A/Dm mice are morphologically and immunologically similar to the mouse mammary tumor virus. Thus, prostate tissues of mice can be a potential source of horizontally transmitted mammary tumor virus in mice of at least some high mammary cancer strains.

Age Factors↗
PubMed1978

Particle--lamella complexes in a case of human benign prostate hyperplasia: brief communication.

Particle--lamella complexes (PLC's), described for the first time, were found in glandular epithelial cells of the hyperplastic prostate tissues from a patient with transitional cell carcinoma of the urinary bladder. PLC's observed in this patient were similar to those seen in human hematopoietic neoplastic cells. They showed cylindroid forms and were composed of concentrically arranged lamellae and particles found in rows between these lamellae. PLC is closely related to rough endoplasmic reticulum (RER), and some PLC's were completely surrounded by RER. Particles approximately 25--30 nm in diameter were similar to ribosomes in size, shape, and electron density; lamellae approximately 10 nm thick appeared circular in cross sections and lamellar in longitudinal sections. Although the nature and function of PLC's are as yet unknown, the present observation indicated that PLC's are not a characteristic structure restricted to malignant tumors of hematopoietic origin.

Endoplasmic Reticulum↗
PubMed1978

In situ embedding method of cells grown in beem capsules for immunoelectron microscopic studies of oncornaviruses.

A technique of in situ embedding of cells grown in BEEM capsules has been devised for immunoelectron microscopic studies of oncornaviruses. As compared to other immunoelectron microscopic procedures, this technique is less time and reagent-consuming. The quality and specificity of this method were tested on well-characterized mouse mammary tumor virus (type B virus) and murine sarcoma virus (type C virus particles). This method gave good results in labeling of the virus particles with ferritin or peroxidase in the cells of mouse tissue cultures. In an application of this method, peroxidase labeling of type B virus particles was obtained in frozen sections of normal prostatic tissues of C3H/Dm and A/Dm strain mice treated with rabbit antiserum to mouse mammary tumor virus from A/Dm strain mouse milk. These results indicate that this method is useful and reliable for immunoelectron microscopy studies of oncornaviruses in tissue culture cells and also in frozen sections of tissues.

Culture Techniques↗
PubMed1978

Electron microscopic studies of intracisternal virus particles in Soehner-Dmochowski murine sarcoma virus-induced bone tumors of New Zealand Black rats.

Soehner-Dmochowski murine sarcoma virus (Moloney)-induced bone tumors of New Zealand Black rats carry two morphologically different types of virus particles, namely, extracellular type C and intracisternal virus particles, which have thus far not been reported. These two types of virus particles have also been observed in the tissue culture cells derived from normal prostate tissues of A/Dm and BALB/c/Dm mice after inoculation of cell-free extracts of these bone tumors. The intracisternal virus particles, 90 to 120 nm in diameter, have always been found in the rough endoplasmic reticulum; they have two inner concentric layers with a relatively electron-lucent center, frequently showing cylindrical, chain-like, or multipolar budding forms. Type C virus particles produced by Soehner-Dmochowski murine sarcoma virus (Moloney)-infected prostate tissue culture cells from A/Dm and BALB/c/Dm mice belong to the murine sarcoma-murine leukemia virus group, as revealed by the fixed immunofluorescence test and by immunoelectron microscopy. The morphological and immunological relationship of intracisternal virus particles and other types of virus particles (such as type C, type H, and intracisternal type A virus particles) and intracisternal virus particles in guinea pig leukemia are defined by routine electron microscopy observations and by immunoelectron microscopy studies.

Animals↗
PubMed1977

Virus-like particles in a case of human prostate carcinoma.

Two morphologically different types of intracisternal virus-like particles were observed electron microscopically in a biopsy specimen of human prostate cancer. Particles of one type were 150-200 nm in diameter and contained either an electron-dense core or two concentric inner layers. Particles of the other type were smaller, 80-100 nm in diameter, and appeared mostly in filamentous or chainlike formation. Both types of particles and budding were observed in endoplasmic cavities of epithelial tumor cells. The particles had ultrastructural characteristics that suggested a viral nature but were different from the known type B, type C, or type H (hamster type R) virus particles. This was the first election microscopic observation in prostate cancer of virus-like particles similar to those previously reported in a case of human breast carcinoma.

Adenocarcinoma↗
PubMed1977

Blood chimeric twins: an example of blood cell chimerism.

A man and his twin sister were found to have two types of circulating red cells. The man had 89% A1 cells of his own and 11% A1B cells derived from his sister. The woman had 12% A1B cells of her own and 88% A1 cells derived from her brother. The two lines of red cells also had different Duffy and Kidd groups. The lymphocyte karyotype in the brother was 68% XY and 32% XX, and that in the sister was 60% XX and 40% XY. The possible mechanisms for producing different proportions of red cells and lymphocytes are discussed.

ABO Blood-Group System↗
PubMed1976

Ultrastructural studies of human prostatic neoplasia.

Forty-two specimens of human prostatic neoplasia (32 carcinomas, eight benign hyperplasia, two bladder tumors infiltrating prostatic tissue, and 15 tissue cultures derived from prostatic neoplasia) were examined by electron microscopy. Intracisternal viruslike particles, 150-200 nm in diameter and budding, were found in epithelial cells of four carcinomas. In some of these particles, an electron-dense central core or two concentric layers were discernible. In addition, particles resembling type C virus particles, 90-130 nm in diameter, were observed in intracytoplasmic vacuoles in five cases of carcinomas and in one case of benign prostate hyperplasia. Thus, viruslike particles were found in 9 of 32 cases of prostate carcinoma and in one of eight cases of benign prostate hyperplasia. Virus particles have, so far, not been found in any of the tissue culture specimens. Further studies are required to determine the nature of these particles and their relationship to the origin of human prostatic neoplasia. Additional observations in both benign hyperplasia and carcinoma include intranuclear mitochondria, multilayered nuclear inclusions, bundles of intranuclear fibrils, intracytoplasmic tubules, extracellular tubulo-filamentous structures, and cilia.ltilayered nuclear inclusions, bundles of ilo-filamentous structures, and cilia.

Carcinoma↗
PubMedDate not supplied

Lymphocyte subsets in lung tissues of non-specific interstitial pneumonia and pulmonary fibrosis associated with collagen vascular disorders: correlation with CD4/CD8 ratio in bronchoalveolar lavage.

This study was designed to evaluate the distribution of lymphocyte subsets in lung specimens that were obtained by open-lung biopsy from 8 patients with idiopathic nonspecific interstitial pneumonia/fibrosis (NSIP) and 10 patients with pulmonary fibrosis associated with collagen vascular disorders (PF-CVD). Distributions of B lymphocytes, CD4-positive T lymphocytes, and CD8-positive T lymphocytes were evaluated immunohistochemically and compared with the cell composition in BALF. Correlation between CD4/CD8 ratios in bronchoalveolar lavage fluids (BALF) and CD4/CD8 ratios in lung tissues was also examined. B lymphocytes were mostly restricted in lymphoid follicles. CD4-positive T lymphocytes were observed inside and around lymphoid follicles and in the thick fibrotic wall of reconstructed alveoli with fibrosis. In contrast, CD8-positive T lymphocytes were diffusely distributed, especially in relatively thin alveoli. Correlation was weak between CD4/CD8 ratios in lung tissue and CD4/CD8 ratios in BALF. However, even in patients with very low CD4/CD8 ratios in BALF, many CD4 lymphocytes were observed in lung tissues, suggesting that CD8-positive lymphocytes diffusely distributed in thin alveolar architecture were more easily recovered in BALF than CD4-positive lymphocytes. Therefore, a low CD4/CD8 ratio in BALF may indicate that the alveolar structure was not severely reconstructed by fibrosis. This is the first report that compared lymphocyte subsets in lung tissues and in BALF.

Aged↗
PubMedDate not supplied

Focal enhancement of expression of c-Met/hepatocyte growth factor receptor in the myocardium in human myocardial infarction.

To determine the distribution and expression level of hepatocyte growth factor (HGF) specific receptor, c-Met, in human myocardial infarction. Autopsies of 13 patients who died without heart diseases (control) and 13 patients with a history of myocardial infarction (2 h to 10 years before death). The harvested myocardial tissues were stained with hematoxylin-eosin (H&E) and immunohistochemically stained for c-Met expression by the avidin-biotin-horseradish peroxidase complex method using an antibody to c-Met. C-Met expression was only slightly increased in control subjects and in noninfarcted myocardium of the test group. In contrast, high expression was noted in the peripheral region of the myocardial infarction and in some hypertrophic myocardial cells. C-Met was not expressed in the infarcted myocardium, but overexpression was noted in the surrounding myocardial cells of blood vessels and in the subendocardium and subepicardium in a band-like pattern. The expression level of c-Met was most enhanced at the time of appearance of coagulative necrosis and least in the myocardium of subjects with old infarcts. Our results indicate that HGF preferentially reaches the ischemic regions of the myocardium and has local and direct effects on the myocardium in patients with myocardial infarction.

Adult↗
PubMedDate not supplied

Inflammatory pseudotumor of the urinary bladder with aberrant expression of cytokeratin. Report of a case with cytologic, immunocytochemical and cytogenetic findings.

BACKGROUND: Cytologic descriptions of inflammatory pseudotumor of the urinary bladder are exceedingly rare. We describe here an additional case of this disease, including its cytologic features and aberrant expression of cytokeratin. CASE: A 35-year-old male presented with gross hematuria but no history of bladder surgery. Urine cytology revealed a few atypical spindle cells suspicious for sarcoma. Histologically, the lesion consisted of spindle cells of various sizes and shapes, proliferating in irregularly running bundles, but no severe nuclear atypia or pathologic mitosis was found. Immunocytochemically, these cells were unexpectedly positive for cytokeratin as well as for vimentin and muscle actin. All metaphase cells examined revealed a normal male karyotype. CONCLUSION: Inflammatory pseudotumor must be distinguished in particular from leiomyosarcoma and spindle cell carcinoma. To avoid an erroneous diagnosis, recognition of this entity is important, together with careful histologic examination and awareness of the possible aberrant expression of cytokeratin.

Actins↗
PubMedDate not supplied

Immunohistochemical findings of nitric oxide synthase expression in urothelial transitional cell carcinoma including dysplasia.

Several in vitro studies have shown that nitric oxide (NO) produced by NO synthase (NOS), such as inducible NOS (iNOS) play an important role in tumor biology. We immunohistochemically examined the expression of iNOS and p53 proteins in patients with transitional cell carcinoma (TCC) of the urinary tract, including adjacent dysplastic lesions to determine the significance of the tumor behavior. Of total 94 tumors, in the present study, 41 (43.6%) tumors exhibited homogeneous immunostaining (diffuse strong positivity in tumor cells, >60%) and 53 (56.4%) tumors heterogeneous staining (variable positivity in tumor cells, 20-60%). No TCCs exhibited negative iNOS immunostaining was found. Thirty (31.9%) of 94 TCCs were positive with anti-p53 antibody, including 23 of homogeneous and 7 of heterogeneous staining. Of 23 TCCs with homogeneous p53 immunostaining, 11 tumors exhibited homogeneous iNOS immunoreaction. In the present study, dysplastic lesions adjacent to carcinomas were detected in 64 cases including 36 TCCs with homogeneous iNOS expression. All dysplastic lesions adjacent to the 36 TCCs with homogeneous iNOS immunostaining exhibited homogeneous iNOS immunostaining. No significant association between iNOS immunoreactivity and any clinicopathological factors as well as p53 immuno-reactivity were found. These in vivo findings provide evidence for frequent iNOS protein expression in TCC. In addition, our observations indicate that overexpression of iNOS expression may be one of the early events in the carcinogenesis of TCC.

Aged↗