Biomedical subjects

A Kurose

Publications and source records attributed to A Kurose.

28 records · Page 2Linked to original sources

PubMed1994

Three cases of extrapulmonary small cell carcinoma occurring in the prostate, stomach, and pancreas.

Small cell carcinomas are fairly common neoplasms in the lung, but tumors featuring similar histological profiles may occur in extrapulmonary organs. Three cases of small cell carcinomas occurring in the prostate (case 1), stomach (case 2), and pancreas (case 3) are presented. Production of hormones was demonstrated immunohistochemically in all cases. In case 2 alpha-fetoprotein (AFP) was elevated in the serum and observed immunohistochemically in tumor cells. Production of AFP is a distinctive feature, which has not been reported in the pulmonary and extrapulmonary cases of small cell carcinoma. Amplification and/or expression of myc gene family have been suggested to be related to the prognosis of pulmonary small cell carcinoma. Amplification of myc genes was not detected in any of our cases, but c-myc protein was demonstrated immunohistochemically in tumor cells of case 1.

Adult↗

PubMed1993

Flow cytometric analysis of the expression of PCNA during the cell cycle in HeLa cells and effects of the inhibition of DNA synthesis on it.

Flow cytometric bivariate DNA/PCNA analysis was performed to investigate the expression of PCNA during the cell cycle and the implication in DNA replication in HeLa cells, using a monoclonal antibody (PC10) to PCNA. The expression of PCNA was evident in almost all cells growing exponentially, when cells were fixed in methanol. The total amount of PCNA altered a little during the cell cycle. However, the treatment with Triton X-100 extracted 80-89% of total PCNA from the cells, resulting in the dramatic change of bivariate DNA/PCNA distribution pattern. PCNA was completely removed from nuclei in both G1 and G2 phases by the detergent treatment, whereas a certain amount of PCNA remained in S phase nuclei. After the treatment of cells with Triton X-100, PCNA was detected exclusively in S phase cells. The bivariate DNA/PCNA distribution pattern in cells treated with Triton X-100 was strikingly so similar to the DNA/BrdUrd distribution pattern that it was unable to differentiate one from the other. It is concluded that the detergent treatment of cells allows the rapid analysis of the cell cycle. The inhibition of DNA synthesis with 10 mM hydroxyurea elevated cellular PCNA content mainly due to the increase in the fraction of the detergent extractable PCNA. It was apparent, however, that in cells incubated with Triton X-100, the pattern of the bivariate DNA/PCNA distribution was not basically different from that in cells without HU treatment. The level of PCNA bound to nuclear structures (PCNA not extracted with detergent) increased in cells arrested at the G1/S boundary with the time of hydroxyurea treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Monoclonal↗

PubMed1992

Brain lesions of the Leigh-type distribution associated with a mitochondriopathy of Pearson's syndrome: light and electron microscopic study.

Pearson's syndrome is a disease of refractory sideroblastic anemia and exocrine pancreatic dysfunction due to abnormal mitochondrial DNA (mtDNA). A male infant with Pearson's syndrome developed necrosis of both thalami and basal ganglia when he suffered from gastroenteritis at 1 year and 11 months of age. He died of sepsis at the age of 2 years and 4 months. Analysis of mtDNA from various organs revealed abnormal mtDNA with deletion by 5 kbp, confirming the diagnosis. At autopsy, the brain had symmetrical cavities in putamen, caudate nuclei and medial nuclei of the thalami. Ferruginous granules in nerve cells in medial thalamic nuclei, and scattered round bodies with neuronophagia in lateral nuclei were found at light microscopic observation. Electron microscopy showed that these granules were composed of radiating spicules and a dense layer containing packed cytoplasmic organelles, respectively. The macroscopic distribution of brain lesions was very similar to and characteristic of Leigh's disease. This similarity leads to the supposition that defective intracellular energy utilization common to Leigh's disease could be responsible for brain lesions in this case. Although the histological appearance was somewhat atypical for Leigh's disease, very acute formation of brain lesions in this case was thought to have caused the histological difference.

Anemia, Sideroblastic↗

PubMed1992

[Cell staining for flow cytometry].

The innovation of biotechnology and computer technology makes it possible to give a quantitative analysis of cellular constituents and to evaluate cellular function accurately. Flow cytometry, which is one of such a new technology, coupled with successive developments of new fluorescence dyes greatly contributes to not only biological research fields but clinical medicine. This article reviews fluorochromes and cell staining with them for flow cytometry, focusing on the measurements of nuclear DNA content. Many of fluorescence dyes binds specifically to nucleic acid. Some of them intercalate double stoichiometrically stranded DNA and the illumination of an appropriate wavelength light excites the dyes, resulting in bright fluorescence proportional to the amount of DNA. However, it is necessary for flow cytometry to realize an optimal condition of nuclear staining with fluorochromes.

Calcium↗

PubMed1990

[An epithelial myoepithelial carcinoma of the parotid gland].

A case of epithelial myoepithelial carcinoma is reported. Histologically, this tumor shows tubular and solid growth pattern. The inner layer of the tubules is composed of cells with an eosinophilic cytoplasm that is surrounded by cells with clear cytoplasms. Clear cells also manifest a solid growth pattern. Immunohistochemical and electron microscopic examinations has revealed that the cells with an eosinophilic cytoplasm have the characteristics of the ductal epithelium and that the clear cells have the characteristics of the myoepithelium. Immunohistochemically, keratin positive clear cells and S-100 protein positive ductal cells were found in our case. This suggests the existence of cells having both ductal and myoepithelial characteristics and this inspected tumor had derived from multipotential cells of intercalated ducts.

Actin Cytoskeleton↗

PubMed1990

[An autopsy case of lethal midline granuloma that terminated in an intracranial hemorrhage].

Reported is an autopsy case of a lethal midline granuloma (LMG) that originally had been manifested as chronic sinusitis and that terminated in intracranial hemorrhage. A 30-year-old woman developed a necrosis of the nasal cavity while being treated for chronic sinusitis for approximately four months. She subsequently died of an intracranial hemorrhage, and an autopsy revealed a necrosis that had progressed from the nasal cavity to the frontal base of the brain, and an infiltration of atypical cells that had an immunoreactivity to the T-cell antigens was observed. Recent studies have strongly suggested the possibility that some cases of an LMG, if not all, may be identical to a T-cell lymphoma. Our case is described and this disease is discussed.

Adult↗

PubMedDate not supplied

Amplification of the c-erbB-2 gene detected by FISH in gastric cancers.

The amplification and overexpression of the c-erbB-2 gene are considered to be implicated in the process of carcinogenesis of a variety of human tumors. The amplification and overexpression of c-erbB-2 were investigated in 48 surgically resected human gastric cancers by means of fluorescence in situ hybridization and immunohistochemistry. DNA ploidy was determined by flow cytometry. The c-erbB-2 amplification was demonstrated as a cluster of signals, suggesting homogeneously staining region (HSR), in three tumors (6.3%) accompanied by the overexpression of its protein. Such overexpression was detected in another tumor without amplification of the c-erbB-2 gene. All tumors with amplification and overexpression of c-erbB-2 were differentiated adenocarcinoma histologically, but only 10.3 and 13.8% of differentiated carcinomas showed amplification and over-expression of the c-erbB-2 gene, respectively. There was no relationship between the amplification and overexpression of c-erbB-2 and the depth of tumor invasion and lymph node involvement. Three of four cases with overexpression of c-erbB-2 were classified into DNA aneuploid tumor.

Adenocarcinoma↗

PubMedDate not supplied

Flow cytometric analysis of p53 expression during the cell cycle.

Mutant p53 expressed in many types of carcinoma lacks an inhibitory function on cell growth, but its role has been unclear. We performed two-parameter flow cytometry (FCM) to elucidate the relationship between the expression of p53 and the cell cycle in A431 cells. Fluorescence in situ hybridization proved that an A431 cell had two p53 genes whereas chromosome 17 was tetraploid. FCM showed that A431 cells expressed constantly high levels of p53 during the cell cycle. Under conditions of both serum deprivation and presence of hydroxyurea, p53 expression was decreased throughout the cell cycle, and the bivariate DNA/p53 distribution pattern during the cell cycle did not change. The expression of p53 was reduced to 60% for the first 4 h after the addition of cycloheximide, and showed no significant changes at least for 20 h. Treatment with Triton X-100 increased p53 immunoreactivity throughout the cell cycle. These results indicate that mutant p53 differs from proliferative markers such as PCNA, Ki-67 and DNA polymerase-alpha, and that there are no links between the expression of p53 and the cell cycle in A431 cells.

Cell Cycle↗

PubMedDate not supplied

Effects of cycloheximide on chromatin-bound and -unbound PCNA in HeLa cells.

We examined the effects of cycloheximide on the amount of chromatin-bound and -unbound PCNA subpopulations in HeLa cells. The chromatin-bound PCNA content decreased rapidly in the presence of cycloheximide, whereas the reduction of the total amount of PCNA was minimal even 24 h after the treatment with cycloheximide. From these data, the half-life of PCNA was estimated to be 31.0 h for chromatin-bound PCNA and 276.8 h for the total.

Chromatin↗

PubMedDate not supplied

Laser scanning cytometry (LCS) allows detailed analysis of the cell cycle in PI stained human fibroblasts (TIG-7).

We have demonstrated a method for the in situ determination of the cell cycle phases of TIG-7 fibroblasts using a laser scanning cytometer (LSC) which has not only a function equivalent to flow cytometry (FCM) but also has a capability unique in itself. LSC allows a more detailed analysis of the cell cycle in cells stained with propidium iodide (PI) than FCM. With LSC it is possible to discriminate between mitotic cells and G2 cells, between post-mitotic cells and G1 cells, and between quiescent cells and cycling cells in a PI fluorescence peak (chromatin condensation) vs. fluorescence value (DNA content) cytogram for cells stained with PI. These were amply confirmed by experiments using colcemid and adriamycin. We were able to identify at least six cell subpopulations for PI stained cells using LSC; namely G1, S, G2, M, postmitotic and quiescent cell populations. LSC analysis facilitates the monitoring of effects of drugs on the cell cycle.

Cell Cycle↗