Search PubMed⌕ Search

Biomedical subjects

E Kubo

Publications and source records attributed to E Kubo.

67 records · Page 4Linked to original sources
PubMed1982

Induction of pigmentation by continuous X-irradiation of amelanotic tumors of B16-XI mouse melanoma and induced change in chromosomes of amelanotic cells.

Non-pigmented tumor cells of B16-XI mouse melanoma were found to contain a diploid number of chromosomes similarly to those of melanotic tumors and the parental cells in tissue culture. A major difference between pigmented and non-pigmented cells was in the number of biarmed chromosomes per cell. There was no difference in growth rate between non-pigmented and pigmented tumors, but growth usually begins about 2 days earlier in the former. Pigmentation lost in the course of serial transplantation was restored by irradiating the non-pigmented tumor continuously with 2,500-3,000 rads/passage of X-rays during six transfer generations. In the course of repeated irradiations, the chromosomes changed structurally and numerically as the pigmentation of the tumor was gradually restored. The observations of tumor growth and chromosomal changes are discussed in relation to the pigmentation of B16-XI melanoma cells.

Animals↗
PubMedDate not supplied

Histologic examination of dislocated lenses.

PURPOSE: To examine histological changes resulting from dislocated and subluxated lenses. CASES: The subjects consisted of 16 patients (aged 52-89 years) who underwent total lens extraction for lens dislocation or subluxation in the Department of Ophthalmology at Fukui Medical University during the period between April 1991 and June 1998. There were 5 patients (6 eyes) with traumatic dislocation and 11 patients (11 eyes) with idiopathic dislocation. RESULT: Rupture of the cortical fibers and migration of the epithelial cells toward the posterior pole of the lens were more frequently noted in patients with traumatic dislocation than in the idiopathic group, and both findings were often simultaneously observed. Rupture of the cortical fibers was considered attributable to external pressure transmitted to the lens. CONCLUSION: We speculate that the concurrent migration and dislocation of the equatorial bow architecture toward the posterior pole was caused by inhibition of differentiation of the epithelial cells to fiber cells by external pressure on the equatorial region.

Aged↗
PubMedDate not supplied

Immunohistochemical study of apoptosis of lens epithelial cells in human and diabetic rat cataracts.

PURPOSE: To evaluate apoptosis of lens epithelial cells by immunohistochemical methods. METHODS: We performed terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) assays on capsulotomy specimens (53 patients, 68 eyes) from patients who had undergone cataract surgery, and on the epithelium of diabetic cataracts in rats (72 rats, 144 eyes). An animal model of diabetic cataracts was prepared by injection of streptozotocin in 3-week-old rats. The specimens of rats were also examined using the proliferating cell nuclear antigen (PCNA) immunohistochemical staining method. RESULTS: Although some TUNEL-positive cells were detected in capsulotomy specimens, we recognized little correlation between their distribution and the morphological classification of the cataracts. In the animal model of diabetic cataracts, TUNEL-positive cells were seen around the regions of accumulated epithelial cells. In the accumulated regions, PCNA-labeled cells undergoing DNA synthesis were also detected. CONCLUSIONS: These results suggest the possibility that apoptosis occurs in human lens epithelial cells. Apoptosis and proliferation of lens epithelial cells may be induced by factors such as hyperglycemia.

Aged↗
PubMedDate not supplied

Histology of anterior capsule edges produced by CCC and DC.

We compared the postoperative characteristics of the anterior capsule edges produced by two incision techniques: continuous curvilinear capsulorhexis (CCC) and diathermy capsulorhexis (DC). We examined the incised rims of human and animal capsules histologically and also compared the configuration and strength of the rims produced in animal experimentation. Histological examination of rabbit lenses revealed that 0.5 seconds was sufficient for coagulation of the anterior capsule: longer times caused deeper cortical tissue damage. Experimentally produced small capsulorhexis (3.5 mm diameter) with DC produced edges were less elastic than with CCC when tension was applied.

Animals↗
PubMedDate not supplied

Possible prognostic markers in conjunctival dysplasia and squamous cell carcinoma.

Conjunctival squamous cell carcinoma (SCC) can develop from carcinoma in situ or severe dysplasia known as conjunctival intraepithelial neoplasia (CIN). Conjunctival intraepithelial neoplasia and SCC are histopathologically well-defined conditions. However, it is difficult to determine the grading of dysplasia by clinical morphologic findings. Recently, proliferating cell nuclear antigen (PCNA) immunostaining, p53 immunostaining, and argyrophilic nucleolar organizer regions (AgNORs) staining have been established as valuable means of studying the biologic behavior of malignant cells. In the present study, these three staining techniques were used to examine histologic preparations of three conjunctival dysplasia and one SCC lesion. Five conjunctival tumor samples were obtained from four patients between July 1993 and October 1995. Following formalin fixation and embedding in paraffin, PCNA, and p53 immunostaining and AgNORs staining was performed with all tissue specimens. The PCNA-positive rate was the highest in SCC, followed by severe dysplasia and mild dysplasia. The p53-positive rate was the highest in severe dysplasia, followed by mild dysplasia, and negative in SCC. The AgNORs-count increased as malignancy advanced. These staining methods, which are markers for proliferative potency and cell differentiation, will be useful for early detection of changes in malignancy and will aid in decisions on treatment and prognosis.

Aged↗
PubMedDate not supplied

Analysis of changes in corneal shape and refraction following scleral buckling surgery.

PURPOSE: A prospective study was performed to investigate changes in corneal shape and axial length following scleral buckling surgery. METHODS: We investigated the changes in corneal shape, refraction, and axial length following scleral buckling surgery in 24 patients who underwent local buckling and 14 patients who underwent encircling with additional segmental buckling. The corneal shape was determined by corneal topography and autokeratometry, refraction was measured by autorefractometry, and axial length was measured by A-mode ultrasonography before surgery, and 1, 2, and 7 days, and 1, 3, and 6 months after surgery. RESULTS: After local buckling, the axial length shortened and a hyperopic change was observed. After encircling with additional segmental buckling, the axial length elongated and a myopic shift was detected. The direction of the surgically induced corneal astigmatic vectors was almost identical to the direction of the buckle. There was a tendency for shorter distances between the limbus and the buckle to be associated with greater absolute values. Astigmatism gradually decreased following surgery and stabilized in about 3 months. CONCLUSIONS: Surgeons should select a surgical procedure to ensure favorable postoperative visual acuity while minimizing changes in the shape of the cornea.

Astigmatism↗