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S Akiya

Publications and source records attributed to S Akiya.

At least 19 recordsLinked to original sources
PubMed1999

Granular-lattice (Avellino) corneal dystrophy.

Granular-lattice (Avellino) corneal dystrophy has rarely been reported in the literature. It consists of a combination of granular and lattice dystrophy. We describe the histopathologic examination of the corneal button of one Japanese patient who had undergone unilateral keratoplasty because of severely decreased vision caused by what had been diagnosed clinically as granular dystrophy. However, on pathologic examination, lesions characteristic of both granular dystrophy and lattice dystrophy were found. We also describe 2 Japanese patients who had a clinical appearance characteristic of both granular and lattice dystrophy. Granular-lattice corneal dystrophy was found in a wider geographic distribution than previously proposed and should not be named after the geographic area.

Adult↗
PubMed1998

Glycosaminoglycan and collagen distribution in the developing human vitreous.

BACKGROUND: We determined the distribution of glycosaminoglycans and collagens in the developing human vitreous. METHODS: Eighty human eyes from 5 gestational weeks to 2 postnatal years of age were used. Glycosaminoglycan components were determined by enzyme digestion with hyaluronidase or chondroitinase AC and ABC and immunohistochemistry for chondroitin, chondroitin-4-sulfate, chondroitin-6-sulfate, and dermatan sulfate. Collagen distribution was determined by immunohistochemistry for types I, II, and III collagens. RESULTS: Enzyme digestion showed that throughout development hyaluronic acid is the main glycosaminoglycan in the vitreous and in the extraocular space at 5-7 gestational weeks. Both areas were filled with mesenchymal cells. Immunohistochemistry showed chondroitin-6-sulfate in the vitreous between 6 and 40 gestational weeks, and chondroitin-4-sulfate between 12 and 40 gestational weeks. Hyaluronic acid and chondroitin sulfate appeared in the retina and around the hyaloid vessels at 12-40 weeks. Immunohistochemistry showed type III collagen in the vitreous and around the mesenchymal cells at 5-7 weeks that was replaced by type II collagen after 8 weeks. CONCLUSIONS: Hyaluronic acid is the major glycosaminoglycan in the vitreous throughout development, except for the transient appearance of chondroitin sulfate at 6-40 gestational weeks. Type III is the main collagen in the early developing vitreous that converts to type II collagen at 8 weeks. The primary and secondary vitreous has the same components as these macromolecules. These vitreous glycosamino-glycans and collagens seem to be produced by mesenchymal cells at an early stage and by the retina and hyaloid vessels during middle and late development.

Adolescent↗
PubMed1998

[Electron microscopic observations of the conjunctiva in epidermolysis bullosa hereditaria].

A 35-year-old female had been clinically diagnosed as having epidermolysis bullosa hereditaria since her skin formed blisters from the time of her birth. Her left and right corneas become clouded at the age of 17 and 31 years, respectively. She was diagnosed as having bilateral secondary glaucoma at the age of 31 years and was medicated with antiglaucoma drugs. When examined by us, both corneas were invaded by conjunctival tissues and intraocular pressure in both eyes was 38 mmHg. Visual acuity was 0.09 (n.c.) in the right eye and she had no light perception in the left eye. A trabeculectomy OD was performed at our hospital. For confirmatory diagnosis, a pathological examination of the conjunctival and dermal tissues was done. Electron microscopic study demonstrated blister formation beneath the basal lamina and lost anchoring fibrils of both tissues. This finding confirmed that she had a receive form of dystrophic epidermolisis bullosa. This is a rare case of dystrophic epidermolisis bullosa with severe corneal changes and glaucoma diagnosed from electron microscopic observations.

Adult↗
PubMed1996

Lattice corneal dystrophy type II associated with familial amyloid polyneuropathy type IV.

BACKGROUND: Finnish-type familial amyloidosis (FAP-IV) is an autosomal, dominantly inherited disorder characterized by progressive polyneuropathy and lattice corneal dystrophy type II. The vast majority of families with this disorder originated from Finland. Only two families, in neighboring districts, have been reported in Japan previously. METHODS: The authors report two additional Japanese patients with FAF-IV. The proband, a 70-year-old man, had decreased perspiration and abnormal facial muscle movement. Results of neurologic examination showed bilateral facial and hypoglossal nerve palsies, and an autonomic disturbance, including orthostatic hypotension and dysfunction of perspiration. Histochemical, immunohistological, and DNA studies confirmed the diagnosis of FAP-IV. RESULTS: Results of ophthalmologic examination showed asymptomatic lattice corneal dystrophy of both eyes, but the appearance of the cornea was different from that described in the patients from Finland. Lattice lines in the authors' patient were very fine, short, and glassy and could be observed with indirect retroillumination, but might be missed with direct illumination by the slit-lamp microscope. The proband's younger half-sister, a 68-year-old woman, showed clinical findings and laboratory data similar to those of the proband. CONCLUSION: The authors report two Japanese patients with lattice corneal dystrophy type II related to FAP-IV. This is the third Japanese family with this disorder, and there is no familial relationship to the two previously reported families in Japan.

Aged↗
PubMed1996

Surmised state of accommodation to stereoscopic three-dimensional images with binocular disparity.

Three-dimensional image (3-D image) was experimentally generated by the binocular disparity principle, and psychological tests were performed in relation to the state of accommodation. An image of a square formed by the time-sharing system using liquid crystal (LC) shutter glasses was displayed before the CRT screen (forward image) by the crossed visual-line method and behind the monitor screen (backward image) by the non-crossed visual-line method. The subjects were requested to subjectively compare each image with the original image on the CRT screen in relation to the size. The forward image displayed by the crossed visual lines looked smaller than the original image, while the backward image displayed by the non-crossed visual lines looked larger. In consideration of the developmental mechanism of micropsia occurring in patients with accommodative palsy or paresis of accommodation and macropsia occurring in patients with accomodative spasm, it was surmised that, in the generation of 3-D image due to binocular disparity, accommodation works so that the original image position is maintained.

Accommodation, Ocular↗
PubMed1995

A case of one eye with gelatinous drop-like corneal dystrophy and the other eye with band-shaped spheroidal corneal degeneration.

The first case of gelatinous drop-like corneal dystrophy in one eye and band-shaped spheroidal corneal degeneration in the other eye was reported. She was a member of Japanese family with gelatinous drop-like corneal dystrophy. A close association between gelatinous drop-like corneal dystrophy and band-shaped spheroidal corneal degeneration was suggested.

Adult↗
PubMed1995

[Molecular genetic analysis of Leber's hereditary optic neuropathy with the 3460 mutation in Japanese pedigrees].

We have identified a point mutation at nucleotide position 3460 in the ND1 gene of complex I in a Japanese pedigree with Leber's hereditary optic neuropathy by sequencing the ND genes in mitochondrial DNA. None of the 60 healthy Japanese had the 3460 mutation. The proband and his mother also had the 7444 mutation in the COI gene of complex IV and became nearly blind at age 19 with visual acuities of 0.02 OD and 0.04 OS We screened 30 patients with bilateral optic atrophy for the 3460 mutation, and identified one male patient who had the 3460 mutation in heteroplasmic fashion without carrying the 7444 mutation. He lost his sight at age 14 but it recovered to 1.2 OD and 0.7 OS about two years and half after the onset. The difference in final visual acuity between these two patients may reflect the degree of reduction in mitochondrial energy production.

Adolescent↗
PubMed1995

[Static characteristics of accommodation on the relationship between accommodative resting position and viewing distance].

The steady-state accommodation of subjects during a 15 min visual task was measured in real time by an infrared optometer to investigate the relationship between accommodative resting position and the effect of viewing distance. When the subjects were loaded at 50 cm (closer than their resting state), the steady-state accommodation showed an inward shift which was enhanced when computation was done. On the contrary, when they worked outside their resting position-2m viewing distance-, an outward shift of steady-state accommodation was seen in the control group who reacted only to the visual objects displayed. For the mental task group this was not evident. It appears that the steady-state accommodation is different between the cases of visual stimuli given inside and outside the resting position.

Accommodation, Ocular↗
PubMed1994

[A study of the relationship between diabetic neuropathy and diabetic retinopathy].

To evaluate the relationship between diabetic neuropathy and retinopathy, we examined autonomic nervous function, postural hypotension, nerve conduction velocity and coefficient of variation of R-R intervals. Forty-five non-insulin dependent diabetic cases were classified as no diabetic retinopathy (group A), simple diabetic retinopathy (group B) and proliferative diabetic retinopathy (group C). These groups did not differ in age or gender. The rate of postural hypotension (depression of systolic blood pressure over 30 mmHg) was 0% in group A, 7% in group Bs and 53% in group C. Nerve conduction velocity in both motor and sensory nerve was delayed over 20% in 0% of group A, 8% of group B, and 33% of group C. In CVR-R, 11% of group A and 7% of group B were decreased, and 44% (during rest) and 33% (during deep breathing) of group C was decreased. Between groups A and B there was no statistical difference. But group C had statistically significant difference from other groups, particularly in postural hypotension. Peripheral neuropathy might be closely related to diabetic retinopathy.

Adult↗
PubMed1994

[A multicenter clinico-epidemiological study of HTLV-I associated uveitis].

To elucidate the clinical and epidemiologic features of HTLV-I associated uveitis (HAU), a multicenter case-control study was performed by collaboration of university hospitals throughout Kyushu and Okinawa and two university hospitals in the central metropolitan area. A total of 426 cases of endogenous uveitis were collected and studied between September 1992 and January 1993; about half of the cases were definable for etiology or clinical entity, and the remaining cases were unknown. Assessment of the serum antibodies to HTLV-I revealed that the group of entity-undefined uveitis had a significantly high prevalence of HTLV-I as compared with the age- and sex-matched control subjects, giving supportive evidence for HAU. The titer of serum HTLV-I antibodies was significantly higher in entity-undefined uveitis than in HTLV-carriers. Assuming that a collection of 50 cases of HTLV-I seropositive, etiology-undefined uveitis represents HAU, its clinical features consisted were: (1) middle-aged, otherwise healthy adults developed acute inflammatory uveal disease and presented with visual haze and/or floaters; (2) the disease showed granulomatous or nongranulomatous anterior uveal reactions accompanied by vitreous opacities and retinal vasculitis; (3) the lesions resolved in response to topical or systemic corticosteroids; (4) the visual outcome was usually favorable; (5) nearly half of the cases had recurrent disease; (6) the cases remained systemically unremarkable, except for two cases of HTLV-I associated myelopathy and eight cases of hyper thyroid disease.

Adolescent↗
PubMed1993

[A case of necrotizing scleritis associated with Epstein-Barr virus infection].

Recently Epstein-Barr virus (EBV) is often reported in association with ocular disease. But EBV has not been reported to cause necrotizing scleritis. A 71-year-old woman developed ciliary injection and peripheral corneal ulcer in both eyes. The lesions did not respond to topical steroid and systemic indomethacin. The sclera became transparent and perforated. EBV serologic antibody titers were strongly positive. Anti-viral capsid antigen (VCA)-IgG was 1: 1,280 and anti-early antigen (EA)-IgG was 1: 640. These serologic results suggested active EBV infection. Using immunofluorescence techniques, the squamous epithelial cells of the conjunctiva were stained with monoclonal antibody against EBV-VCA and strongly stained with antibody against IgG. The results of serologic test and the immunofluorescence techniques appeared to suggest that the necrotizing scleritis was caused by EBV.

Aged↗
PubMed1993

[Effects of dibutyryl cyclic AMP on the gene expression during the differentiation of retinoblastoma cells (Y 79) in culture].

Cultured human retinoblastoma cells (Y79) were induced to differentiate by dibutyryl cyclic AMP(Bt2cAMP). We examined the effects on the mRNA levels of several cellular genes when the induction of differentiation was monitored by observation of the cellular processes. Bt2cAMP(1mM) treatment produced significant extension of cellular process after 3 days. We examined the mRNA levels of N-myc gene(oncogene), Rb(anti-oncogene, retinoblastoma gene) and nucleolin (nucleolar protein) being linked with ribosome biosynthesis. The mRNA levels of all these genes decreased for 3 days after Bt2cAMP treatment. These results suggested the possibility that Y 79 cells were induced to differentiate by down-modulation of both N-myc gene expression and ribosome biosynthesis in the nucleolus following treatment of Bt2cAMP. Furthermore, the gene expression of the retinoblastoma gene is likely to be downregulated by this condition even if the product of mRNA is not functional.

Bucladesine↗
PubMed1992

Differences of L-myc polymorphic patterns of neuroblastoma in patients under 1 year versus older ages: a preliminary report.

The age of the patient at the onset of symptoms or at diagnosis is generally accepted as one of the most important prognostic factors of neuroblastomas (NBs). Children less than 1 year of age have a better survival rate than older patients, but the reason for this is unknown. Forty-eight unselected NB patients were divided into two groups: less than 1 year (younger NB patient) and over 1 year (older NB patient) of age at diagnosis. Two of 12 younger NB patients and 18 of 36 older NB patients had N-myc amplification in their tumors. To elucidate further the possible genetic difference between younger and older NB patients, studies of restriction fragment length polymorphism (RFLP) of the L-myc gene was carried out in these two groups. The L-myc locus showed 2-allele polymorphism, allele L(10 kb) and S (6.6 kb), after digestion with EcoRI. Patients homozygous for L-band have been reported as individuals having less metastatic potential in some cancers. The allele frequencies of L and S in neuroblastomas of younger NB patients were 0.50 and 0.50, while those of older NB patients were 0.35 and 0.65, respectively. Although we did not determine L-myc RFLP in normal tissue of individual patients, we expect that the distribution of allele L and S is partly affected by possible allelic loss involving the L-myc region. However, the L-myc RFLP patterns in younger NB patients were the same as those of normal individuals and significantly differed from those of older NB patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗
PubMed1992

[Accommodative resting position and the effect of viewing distance on after-effects of accommodation and the pupil].

The resting position of accommodation is determined by the equilibrium established between sympathetic and parasympathetic tone. To accommodate for near objects is brought about by excitation of the parasympathetic, and distant objects call for excitation of the sympathetic system. To investigate accommodation and pupil after-effects following the 10 min visual task with stereoscopic three dimensional image, the measurements of the dynamic responses of accommodation and pupil were made. When the subjects worked at 0.4 m (closer than their resting state) and at 1 m corresponded to their resting positions, the response delay in accommodative relaxation occurred in each condition. When they worked at outside their resting position (1.5 m and 3 m viewing distances), the significant response delay in contraction in the groups of 1.5 m and 3 m, and the increases of accommodation error and the area of miosis were shown. There was a fact that the after-effect on accommodation and pupillary function was different between in the case of tasks given inside and outside their resting positions.

Accommodation, Ocular↗
PubMed1992

[Histopathological study of retinopathy of prematurity].

Using light and electron microscopy, we studied the histopathological findings of retinopathy of prematurity (zone II, stage 3). The infant was born at 32-week gestational period and the birth weight was 1,255 g. He suffered from intracranial hemorrhage and hydrocephalus, and died at 78 days old. The ophthalmoscopic findings of both eyes at 72 days after birth showed that the intermedia was clear. The optic disc and posterior pole showed normal findings. Ridge formation with non-vascularized retina was seen at the equator of all quadrants of the fundus except the nasal quadrant of retina. Light and electron microscopic studies showed the following; in the most periphery of the vascularized retina, endothelial cell proliferation with the capillary lumen of glomeruloid tufts (rearguard) were seen. There were the aggregation of immature mesenchymal cells (vanguard) near to the rearguard. The cytoplasmic organelles of spindle cells in the non-vascularized retina were different from those of surrounding glial cell. Therefore, they were thought to be mesenchymal cells in the non-vascularized retina. Between the vanguard and the rearguard, the proliferative tissues composed of immature endothelial cells and mesenchymal cells extended into the vitreous body through the inner limiting membranes, and they formed the fibrovascular membranes on the retina. It was concluded that fibrovascular proliferation on the retinal surface in the active case of retinopathy of prematurity was composed of immature endothelial cells with vascular lumen and mesenchymal cells.

Humans↗
PubMed1992

[Effects of cadmium on the gene expression of retinoblastoma (Y79) cells in culture].

We examined the effects of cadmium on the mRNA levels of several genes in cultured retinoblastoma (Y79) cells. After Y79 cells were treated with 15 microM CdCl2, RNA was extracted at a given time. The levels of retinoblastoma gene (Rb) mRNA decreased after cadmium treatment, although it was unlikely that the Rb gene product is functional in this cell line. The N-myc gene (oncogene) is constitutively expressed in untreated Y79 cells but its mRNA levels also decreased following cadmium treatment. On the other hand, the mRNA levels of both heat-shock protein (hsp 70) and metallothionein gene, both having physiological protective effects, increased under these conditions. These results indicate that Y79 cells have physiological protective responses to such a heavy metal as cadmium and that both Rb and N-myc gene expressions are down-modulated in the presence of cadmium.

Cadmium↗
PubMed1991

Down modulation of N-myc, heat-shock protein 70, and nucleolin during the differentiation of human neuroblastoma cells.

Cultured human neuroblastoma (GOTO) cells were induced to differentiate by dibutyryl cyclic AMP (Bt2cAMP) and/or retinoic acid (RA). A combination of Bt2cAMP (1 mM) and RA (1 microM) yielded the most significant networks of neurites after 3 to 4 days, this being associated with the reduction of N-myc mRNA levels. Next, we examined several cellular genes that were possibly linked with changes in N-myc gene expression under these conditions. Among the genes examined, both nucleolin and a major heat-shock protein (hsp70) mRNAs showed changes concomitant with those in N-myc mRNA levels when induced by Bt2cAMP and RA. Dibutyryl cAMP alone induced several short cellular processes and caused a marked decrease in N-myc mRNA within 2 days. RA alone induced a few long and straight neurites along the longitudinal axis of individual cells and a significant decrease in growth rate but showed neither network formation nor a decrease in N-myc gene expression. These results indicate differential effects of Bt2cAMP and RA on the regulatory mechanisms of both cell proliferation and differentiation and also indicate a possible association of expression of N-myc gene with those of hsp70 and nucleolin genes.

Bucladesine↗