PubMed Health⌕ Search

Biomedical subjects

Y Kitajima

Publications and source records attributed to Y Kitajima.

At least 199 records · Page 11Linked to original sources
PubMed1983

The distribution of keratin type intermediate-sized filaments in so-called mixed tumour of the skin.

Epithelial cells can be distinguished from various non-epithelial cells by the presence of keratin-type intermediate-sized filaments, which can be detected by immunofluorescence microscopy, using antibodies to alpha-keratin. In the present study, two types of antibodies were obtained. One of them was specific for alpha-keratin (mol. wt. 49,000 to 69,000 daltons) in whole epidermis, and the other for alpha-keratin (mol. wt. 62,000 and 69,000 daltons) in prickle and granular cells but not in basal cells. Four cases of so-called mixed tumour of the skin were studied by immunofluorescence microscopy using these antibodies. Tumour cells nests of cuboidal and polygonal cells, tubular structures and keratinous cysts reacted with these antibodies, as did individually-dispersed tumour cells within the myxoid and chondroid matrix. These results indicate that all the tumour cells of the so-called mixed tumour of the skin are of epithelial origin. Differences in staining intensity between these tumor cells and their specificity for these two antibodies are discussed with reference to keratin differentiation in tumour cells.

Adult↗
PubMed1982

A simplified method for studying fibrous proteins in psoriatic scales obtained by tape stripping.

Polyacrylamide gel electrophoretic investigations were carried out on solubilized proteins from psoriatic and normal stratum corneum obtained by adhesive tape stripping. The proteins in the scales adhering to the tape were solubilized by incubating the tape in 1% sodium dodecyl sulphate (SDS) solution. The electrophoretic behaviour of these solubilized proteins on SDS-polyacrylamide gel was compared with the alpha-fibrous proteins (keratin) of callus. The proteins isolated from callus of normal human heel showed six main bands which were similar to those of the keratin isolated by the 8 M urea-mercaptoethanol method. The lesional skin of forty-five psoriatic patients consistently showed nine main bands on polyacrylamide gels, but only two main bands were observed in the non-lesional, non-heel skin. Six of these nine bands had mobilities and relative intensities almost identical with those of alpha-keratin extracted by the mercaptoethanol method, but the other three bands had greater mobilities on the gels. These results suggest that this technique may have considerable potential for studying changes in alpha-keratin in patients with psoriasis and other disorders of keratinization.

Callosities↗
PubMed1980

Ultrastructural characterization of the extramammary Paget cell plasma membrane: a freeze-fracture study.

The plasma membrane ultrastructure of the extramammary Paget cells was characterized by freeze-fracture electron microscopy, which was first employed for the study of Paget cells. The Paget cell plasma membrane revealed a flat fractured plane with much fewer and smaller desmosome-particle aggregations than those of the keratinocyte. No gap junctions were detected. Many intramembranous particle-free vesicles were seen in the intercellular spaces. Particle-free blebs projecting from the plasma membranes were seen on some cell surfaces. These features greatly differed from those of keratinocytes. On the other hand, an increase of gap junctions was noticed o the keratinocytes around or in the Paget's disease lesions.

Aged↗
PubMed1980

[Safety evaluation of DE-020 eye drops--eye irritation test and subacute toxicity test in rabbits (author's transl)].

Basic experiments on safety evaluation of 0.3%, 1% and 3% solution of KW-1062 (DE-020 eye drops) were carried out. These eye drops applied topically to rabbits eyes had no undesirable local or systemic effects as follows: 1. Repeated instillations of DE-020 eye drops (One drop every 1 hr for 4 hrs) showed no significant irritation except only a temporary and slight congestion localized at the conjunctivae. 2. Daily instillation of DE-020 eye drops (3 times daily for 28 days) showed no abnormal findings in the eye mucosa, clinical signs, body weight, hematological examination, biochemical examination, autopsy, organ weight and histopathological examination.

Aminoglycosides↗
PubMed1979

Effects of lipid-phase separation on the filipin action on membranes of ergosterol-replaced Tetrahymena cells, as studied by freeze-fracture electron microscopy.

The effects of lipid-phase separation on the filipin action on pellicle membranes of ergosterol-replaced Tetrahymena pyriformis cells were studied by freeze-fracture electron microscopy. The pellicle membranes with phase separations induced by chilling from 34 degrees C (growth temperature) to lower temperatures (30, 22 and 15 degrees C) were treated with filipin. This produced filipin-induced lesions ("pits") only in the particulated (liquid) regions along the margin between solid and liquid domains, while they were produced in the particle-free (solid) areas when membranes were chilled to 15 degrees C. The pellicle membranes with lesions induced by filipin at 34 degrees C were chilled to 22 degrees C. This chilling raised larger particle-free areas and more condensed particle-aggregations on the membranes than on the membranes without the filipin treatment. These results suggest that the membrane fluidity affects induction and development of the ergosterol-filipin complex in the membrane.

Animals↗