Search PubMed⌕ Search

Biomedical subjects

S Hosaka

Publications and source records attributed to S Hosaka.

120 records · Page 7Linked to original sources
PubMed1978

Motility of rat ascites hepatoma cells, with reference to malignant characteristics in cancer metastasis.

The motility of four strains of rat ascites tumor cells in an agar medium was studied quantitatively by means of time lapse cinematography. The motility of these cells differed characteristically with each strain. Yoshida sarcoma and AH-66F cells showed active locomotion and partial movement markedly, while AH-130 and AH-100B cells made no locomotion and only a slight movement.

Animals↗
PubMed1977

Growth behavior of ascites tumor cells in three-dimensional agar culture.

Growth behavior in vitro of ascites tumor cells was examined for a model study on the invasion in cancer. For this purpose three-dimensional agar culture was used. Seventeen strains of tumor cells were used. These tumor cells grow floating in ascites as single isolated cells (single cell strain) or forming different per cent of cell aggregates (island type strain). Plating efficiencies of tumor cells were variable, depending on the kinds of tumor stain. It was noted that FM3A cells of the cultured cell line showed almost 100% plating efficiency irrespective of the number of cells inoculated. Tumor cells formed 3 types of colony; that is solid type, mushroom-shaped and disk-shaped colony. These three types of colony were observed in all the tumor strains tested, depending on the position in agar layer. The cells of single cell strains showed the tendency to form loose colonies in which cell contact was loose and cells were easy to liberate from the periphery of the colony. The cells of island type strains showed the tendency to form packed colonies in which cell contact was tight. Growth behavior of cells of ascites tumor in agar medium showed good correlation with that in susceptible animals.

Animals↗
PubMed1977

Altered growth behavior of virus-transformed cells after treatment with dextran sulfate.

Growth behavior in vitro of 3T3 cells and the cells transformed by polyoma or SV40 virus was studied after their treatment with dextran sulfate. The transformed cells treated with dextran sulfated showed decreased saturation density compared with untreated cells, whereas saturation density of 3T3 cells was hardly affected by treatment with dextran sulfate. The ratio of saturation density of untreated SV3T3 cells to that of the treated cells was 64.1% at 5 microng/ml and was 43.4% at 10 microng/ml of dextran sulfate. In Py3T3 cells the ratio was 45.0% at both concentrations of 10 and 20 microng/ml. Plating efficiency was not affected in 3 cell lines tested after treatment with dextran sulfate. The treated cells showed a tendency to form thin and not piled-up colonies in the central area. The treated SV3T3 and Py3T3 cells were flattened in shape compared with the untreated cells. In agar medium the treated SU 3T3 and Py 3T3 cells showed the tendency to stop growing after forming small colonies, whereas the untreated cells kept growing anf formed large colonies. These results suggested that dextran sulfate altered temporarily the growth of the transformed cells to that of untransformed cells.

Agar↗
PubMedDate not supplied

Selectivity and sensitivity in the measurement of reactive oxygen species (ROS) using chemiluminescent microspheres prepared by the binding of acridinium ester or ABEI to polymer microspheres.

Two kinds of chemiluminescent microspheres were prepared as tools for measuring reactive oxygen species (ROS) released into phagosomes in phagocytizing cells, by chemically binding acridinium ester or ABEI (isoluminol derivative) to polymer microspheres, and were examined from the viewpoint of specificity and sensitivity to ROS. Acridinium ester-bound microspheres (AE-ms) were found to be a sensitive probe to superoxide anion and hydrogen peroxide under a neutral condition (pH 7.2). AE-ms emitted strong chemiluminescence (CL) by hypoxanthine (HPX)/xanthine oxidase (XOD) or hydrogen peroxide. The CL by HPX/XOD was initially inhibited by superoxide dismutase. At pH 5.6, the CL intensity from AE-ms in the presence of HPX/XOD was reduced to about one-eighth of that at pH 7.2. ABEI-bound microspheres (ABEI-ms) were found to be a selective probe for singlet oxygen although not highly sensitive. ABEI-ms emitted CL of moderate intensity with hydrogen peroxide/myeloperoxidase (MPO), but not with hydrogen peroxide alone or with hypochlorite/MPO at pH 5.6. The CL from ABEI-ms with hydrogen peroxide/MPO was completely inhibited by azide. ABEI-ms did not emit CL in the presence of HPX/XOD or by potassium superoxide at pH 5.6. The result of supplemental experiments using dissolved chemiluminescent probes and non-enzymatically generated ROS supported the above-described selectivity and sensitivity of chemiluminescent microspheres.

Acridines↗
PubMedDate not supplied

Comparative study of antioxidants as quenchers or scavengers of reactive oxygen species based on quenching of MCLA-dependent chemiluminescence.

The quenching or scavenging effect of non-enzymatic antioxidants against reactive oxygen species (ROS) was studied by comparing the degree of suppression of chemiluminescence (CL) caused by the oxidation of MCLA (methoxylated Cypridina luciferin analogue) by ROS. MCLA-dependent CL caused by O2- was effectively quenched by ascorbic acid, beta-carotene, lycopene and astaxanthin, while it was enhanced by alpha-tocopherol. The CL by 1O2 was quenched effectively by beta-carotene, lycopene and astaxanthin, moderately by ascorbic acid, and slightly by alpha-tocopherol. beta-Carotene and alpha-tocopherol remarkably suppressed the CL when ROS was HO*. The present study revealed that MCLA-dependent CL assay provides a simple and rapid method for the evaluation of antioxidants as a quencher or scavenger against any kind of ROS.

Antioxidants↗
PubMedDate not supplied

Carcinogenicity examination of inflorescence of Zingiber mioga Roscoe.

The carcinogenicity of mioga was examined in ACI and Fischer 344 rats. In Experiment I, a test group of ACI rats received diet containing mioga for 365 days, and the control group received normal basal diet. The experiment was terminated 480 days after the start of feeding. In Experiment II, a test group of Fischer 344 rats received diet containing mioga throughout the experiment of 639 days and the control group received normal diet. Female ACI rats in Experiment I developed significantly more urinary bladder tumors than the control group. No carcinogenic activity was observed in males in Experiment I or males or females in Experiment II.

Animals↗
PubMedDate not supplied

Evaluation of nano-optical probe from scanning near-field optical microscope images.

We studied a nanometre-sized optical probe in a scanning near-field optical microscope. The probe profile is determined by using a knife-edge method and a modulated transfer function evaluation method which uses nanometre-sized line-and-space tungsten patterns (with spaces 1 microm to 50 nm apart) on SiO2 substrates. The aluminium-covered, pipette-pulled fibre probe used here has two optical probes: one with a large diameter (350 nm) and the other with a small diameter (10 nm). The small-diameter probe has an optical intensity approximately 63 times larger than that of the large-diameter probe, but the power is about 1/25 of that of the large probe.

Journal Article↗
PubMedDate not supplied

Repair of coarctation with persistent fifth arterial arch and atresia of the fourth aortic arch.

Coarctation of the aorta with persistent fifth arterial arch and atresia of the fourth aortic arch between the left common carotid and left subclavian arteries was treated surgically in a two-month-old boy with transposition of the great arteries and double-outlet right ventricle. The aortic arch was repaired using side-to-side anastomosis of the left common carotid and left subclavian arteries, patch repair of the coarctated segment at the origin of the left subclavian artery, and ligation of the patent ductus arteriosus. Pulmonary arterial banding and balloon atrioseptostomy were performed for associated anomalies.

Anastomosis, Surgical↗