Search PubMed⌕ Search

Biomedical subjects

S Kurihara

Publications and source records attributed to S Kurihara.

264 records · Page 15Linked to original sources
PubMedDate not supplied

Radioimmunoassay for dexamethasone 17,21-dipropionate and its metabolites in plasma and urine after topical application.

A sensitive radioimmunoassay for dexamethasone 17,21-dipropionate and its four metabolites in human plasma and urine has been developed using single anti-dexamethasone antiserum. The antiserum was obtained by immunizing rabbits with dexamethasone-3-oxime-bovine serum albumin conjugate. All of the endogenous steroids tested cross-reacted less than 0.07%. Before radioimmunoassay, dexamethasone 17,21-dipropionate and dexamethasone 17-propionate were hydrolyzed to dexamethasone, and 6 beta-OH-dexamethasone 17-propionate was hydrolyzed to 6 beta-OH-dexamethasone in 3% ammonia/methanol at 5 C for 16 h. A standard curve was established with a useful range between 0.005 and 2 ng in the case of dexamethasone, between 0.05 and 5 ng in the case of 6 beta-OH-dexamethasone. Measurement of plasma concentrations and percent urinary excretion of the metabolites in healthy men was performed following occlusive dressing of dexamethasone 17,21-dipropionate cream and ointment. The main metabolites in plasma were dexamethasone 17-propionate and dexamethasone, which increased gradually and reached maximum levels (160-200 pg/mL) at 24-32 h after application. The major metabolites observed in urine were 6 beta-OH-dexamethasone 17-propionate and 6 beta-OH-dexamethasone. Total percentage of their urinary excretions within 72 h after application amounted to 0.28-0.50% of the dose administered.

Administration, Topical↗
PubMedDate not supplied

Histopathological safety evaluation of polyethylene glycol applied subcutaneously in mice.

Polyethylene glycol is used as a non-aqueous solvent for a variety of medical agents. We believe it could also be used as a base component in root canal filling material and aimed to test the histological safety of subcutaneously injected polyethylene glycol. We injected polyethylene glycol subcutaneously into the dorsal area of 30 6-week-old anaesthetized male ddY mice. An equal number of mice were injected with propylene glycol as controls. One week, 3 weeks and 9 weeks after injection, the tissue surrounding the injection site was removed from 10 mice in each group and examined. We found no histopathological changes, degeneration, necrosis, foreign body reactions or granulation tissue proliferation in either group. Some inflammatory cell infiltration was observed in both groups. Based on these results, we believe that polyethylene glycol could be used safely as a base component of biomaterials for internal medical use, such as in root canal filling material.

Animals↗
PubMedDate not supplied

Histopathological evaluation of subcutaneous tissue reaction in mice to a calcium hydroxide paste developed for root canal fillings.

We aimed to evaluate the subcutaneous tissue reaction to a new calcium hydroxide paste for root canal fillings developed by Neo Dental Chemical Products Co., Tokyo, Japan. We injected calcium hydroxide paste and a water-based control subcutaneously into the dorsal area of 6-week-old anaesthetized male ddY mice. The tissue surrounding the injection sites was removed from mice in each group, 2 days, 1 week, 3 weeks and 12 weeks after the injection, and histopathologically examined. We found necrotic and degenerative changes, as well as foreign body reaction or proliferation of granulation tissue in specimens from both groups until 3 weeks after the injection. Some lymphocyte infiltration was observed in the 12-week specimens of the control group only. We conclude that calcium hydroxide paste is safe to use as a root canal filling material.

Animals↗
PubMedDate not supplied

Cytomorphologic study on the atypical cells following cryosurgery for the treatment of chronic cervicitis.

One hundred and twenty-nine patients of chronic cervicitis were treated by cryosurgery and periodically followed up by Pap smears and biopsies. Cytomorphologic studies were carried out on atypical cells following cryosurgery. Atypical cells were detected within four weeks. These were divided into two categories. The first group consisted of cells with abundant cytoplasm and occurred in sheets, aggregates and/or as isolated forms. Irregular nuclear borders were observed in 5.1 per cent and fine granular chromation pattern was found in 99.4 per cent. Irregular nucleolar borders were observed in 7.5 per cent and macronucleoli, over 2.5 microns in diameter, were disclosed in 11.3 per cent. Nuclei within 10 microns in diameter were observed in 56.6 per cent, and the maximum length was 20 microns. It was suggested that these cells were exfoliated from either basal cell hyperactivity or atypical reserve cell hyperplasia. The second group consisted of cells with scanty cytoplasm of bare nuclei and occurred in aggregates. Irregular nuclear borders were observed in 1.7 per cent and fine granular chromatin patterns were found in 99.7 per cent. Irregular nucleolar borders could not be encountered. Macronucleoli were observed in only 0.4 per cent. Nuclel within 10 microns in diameter were observed in 95.3 per cent and the maximum measured length was 15 microns. It was suggested that these cells could be derived from reserve cell hyperplasia or from immature squamous metaplasia. In conclusion, atypical cells following cryosurgery exfoliate from the regenerating tissue in which atypia is frequently observed. The cells of the first group have identical features with those observed in the cases of tissue repair; on the other hand, the cells of the second group were derived from reserve cell hyperplasia or from immature squamous metaplasia.

Cell Nucleolus↗
PubMedDate not supplied

Incidence of herpes infection of the uterine cervix observed in cytologic specimens in the Tokyo metropolitan area.

In a high-volume cytology laboratory in the metropolitan Tokyo area, the incidence of cytologically diagnosed herpes infection in cervical scraping smears of the female genital tract was studied according to the year-by-year changes, age distribution, seasonal variation and types of cytologic alteration. The overall incidence over the 12 years studied was 0.007% (87 cases among 1,230,773 examined). The incidence varied from 0.003% to 0.005% in the early 1970s (except for 1973) and increased to 0.011% in the last three years (1980 to 1982). A large increase was noted in younger age groups in comparison with middle and older age groups. There was a tendency for the infection rate to be higher in the spring (0.011%) and lower in the fall (0.005%). Multinucleation and a ground-glass appearance were observed in the infected cells in almost every case while eosinophilic inclusion bodies were found in 20.7% of the cases.

Adult↗
PubMedDate not supplied

Carcinosarcoma of the uterus. Cytologic and ultrastructural features.

A 56-year-old woman presented with a carcinosarcoma consisting of a small focus of adenocarcinoma and a larger endometrial stromal sarcoma component. Although a preoperative endometrial biopsy revealed only adenocarcinoma, an endometrial smear obtained with an endometrial brush sampler revealed many undifferentiated malignant cells and a smaller number of adenocarcinoma cells. These undifferentiated malignant cells were cytologically identical to the stromal sarcoma cells in an imprint smear from the surgically removed tumor. The cellular and ultrastructural features of the stromal sarcoma are described in detail.

Carcinosarcoma↗
PubMedDate not supplied

Cytologic and biologic studies of endometrioid carcinoma of the ovary.

The cytologic findings in an ovarian endometrioid carcinoma were investigated, and biologic characterization was performed. Cytologic findings from the ascitic fluid revealed characteristics of adenocarcinoma, such as fine cytoplasm, anisochromasia and prominent nucleoli; findings characteristic of endometrioid carcinoma of the ovary were not found, though a cluster of carcinoma cells on imprinted smears was similar to that of endometrial carcinoma cells. A morphologic comparison between the cells from the ascitic fluid and cells cultured from the ovarian endometrioid carcinoma showed their similarity. Biologic characterization showed a modal chromosome number of 103, a 74.4-hour population doubling time of the cell line and 0 plating efficiency. Heterotransplantation was achieved in one of the four hamsters (25%).

Adenocarcinoma↗
PubMedDate not supplied

An analytic cellular evaluation of aspirated smears from transplanted human endometrial adenocarcinoma in nude mice treated with 17 beta-estradiol and progesterone.

The effects of 17 beta-estradiol and progesterone on human endometrial adenocarcinomas grafted into BALB/c nude mice were studied. Cytologic studies were made on aspiration biopsy smears obtained from the grafts with a fine needle. Mitotic figures were frequently observed in the cells obtained from 17 beta-estradiol-treated mice, whereas there were few mitotic figures in cells from progesterone-treated ones. Progesterone produced such morphologic changes as multinucleolation and cytoplasmic vacuolization. Untreated tumors and those treated with 17 beta-estradiol were solid and were interpreted as poorly differentiated adenocarcinomas. Progesterone-treated tumors were slightly soft but were also interpreted as poorly differentiated adenocarcinomas; however, central necrosis was seen frequently, and differentiation occurred at the margin of these tumors. 17 beta-estradiol promoted increased tumor growth, whereas progesterone produced differentiation and inhibited tumor growth.

Adenocarcinoma↗
PubMedDate not supplied

Effect of rapid cooling on toad and guinea pig cardiac muscles.

When bathing solution temperature was lowered rapidly to below 5 degrees C, contracture was observed in toad and guinea pig cardiac muscles (Rapid Cooling Contracture, RCC). RCC in toad cardiac muscle was observed even in the presence of TTX and Mn, and enhanced by reducing [Na]o and caffeine. RCC in guinea pig cardiac muscle showed two components; phasic component was dependent on stimulation frequency before cooling, stimulation period, [Ca]o, and [Na]o; tonic component was not dependent on these factors, but was enhanced by reducing [Na]o and in high [K]o solution. From these results, the possible role of Ca ion accumulated at intracellular sequestered sites in cardiac muscle was discussed in relation to excitation-contraction (E-C) coupling.

Animals↗