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Biomedical subjects

S Hayasaka

Publications and source records attributed to S Hayasaka.

At least 127 records · Page 7Linked to original sources
PubMed1993

Disturbance of neuronal migration in mouse cerebral cortex by low-dose gamma-radiation.

We show that neuronal migration is disturbed by low-dose gamma-radiation of 0.24 Gy in the developing cerebral cortex of mice and suggest that neuronal progenitors in the S phase of mitosis are more sensitive than those in the G1/G0 phase. To pulse-label the fetal cells pregnant Slc:ICR mice were injected with bromodeoxyuridine (BrdU) at 10.00 pm on day 16 of pregnancy or at 9.30 am on day 17. The mice then were exposed to 0.24 Gy gamma- or sham-irradiation at 10.00 am on day 17 of pregnancy. At the time of exposure cells labeled on day 16 were regarded as having completed mitosis, and those labeled on day 17 as being in the S phase. Cell death in the fetal ventricular zone after exposure was negligible. Dams were allowed to give birth and rear their litters. Brain samples obtained from offspring on the 2nd day after birth and at 6 weeks of age were used for the immunohistochemical examination of BrdU-labeled cells. Labeled cells remaining in the ventricular zone were significantly more numerous in irradiated animals than in sham-exposed ones on the 2nd day after birth, in mice treated prenatally with BrdU on day 17 of pregnancy; whereas, mice treated with BrdU on day 16 showed no statistically significant difference. At 6 weeks of age, in both groups most of the labeled cells were present in layers II-III of the SmI cerebral cortex. But, in the irradiated animals the labeled cells in these layers were significantly fewer and those in layers IV-VI more numerous than in the sham-exposed mice in both group treated with BrdU on day 16 or 17.

Animals↗
PubMed1993

Patients with asteroid hyalosis and visible floaters.

Four patients with asteroid hyalosis who complained of seeing multiple spherical floaters were examined. Except for multiple brilliant particles in the gelatinous vitreous, no abnormalities were found by ophthalmoscopic examination. Asteroid bodies usually cause no visual symptoms in most patients. Therefore it is unusual that our patients with asteroid hyalosis perceived floaters. We concluded that it was because there had been no vitreous detachment so that the asteroid particles were located close enough to the retina to be perceived as floaters.

Aged↗
PubMed1993

Various fundus manifestations in a Japanese family with Best's vitelliform macular dystrophy.

Recently we examined 7 members in one Japanese family with Best's vitelliform macular dystrophy. Five family members in three generations had abnormal electro-oculographic (light peak/dark trough ratio) and normal electroretinographic responses, but their fundus manifestations varied. The proband (a girl) had yellowish macular lesions in both eyes and a neovascular membrane and subretinal hemorrhage in the left macula. The proband's grandfather had mottled macular lesions bilaterally and a mottled extramacular lesion in the left eye. The proband's father had yellowish macular lesions in both eyes and an extramacular lesion in the right eye. The proband's sister had ophthalmoscopically normal fundi. The proband's brother had yellowish macular lesions bilaterally. We believe that finding a variety of fundus manifestations of Best's vitelliform macular dystrophy in one family, as reported in this study, may be uncommon.

Adult↗
PubMed1993

Initial rapid decrease in visual acuity in siblings with Stargardt's disease.

Two siblings with Stargardt's disease who had an initial rapid decrease in visual acuity were reported. The 8-year-old boy and his 5-year-old sister experienced a bilateral visual decrease within a period of 3 months. Their parents had a consanguineous relationship. Macular changes and blocked choroidal fluorescence were noted bilaterally in both children. Normal color vision, normal or subnormal electroretinographic findings, and subnormal electro-oculographic responses were found. Stargardt's disease should be included in the list of conditions showing rapid decrease in visual acuity.

Child↗
PubMed1993

A Japanese family with Grayson-Wilbrandt variant of Reis-Bücklers' corneal dystrophy.

A 50-year-old man (the proband) experienced recurring attacks of ocular irritation and had had bilateral ring-shaped anterior corneal opacity since adolescence. Corneal sensation was normal. The proband's 15-year-old daughter also had recurring episodes of ocular irritation and bilateral fleck-like anterior corneal opacities. The proband's deceased father and brother reportedly had similar corneal lesions from adolescence. We believe that the corneal findings in this family may be similar to those found in patients with the Grayson-Wilbrandt variant of Reis-Bücklers' corneal dystrophy.

Adolescent↗
PubMed1993

Chest x-rays before ophthalmic surgery.

We retrospectively reviewed clinical records and preoperative chest x-ray films of 636 patients who had been admitted for ophthalmic surgery in 1990 and 1991. In our hospital, a preoperative chest roentgenogram routinely was examined for each patient. A total of 228 patients (35.8%) had an abnormal preoperative result. These abnormalities were more frequent in patients older than 40 years of age than in younger patients. Pulmonary fibrosis and calcification were the most common abnormal findings. Also, we noted that 202 patients (31.8%) had a chronic, previously known, or suspected, finding, and 26 patients (4.1%) had a new or unsuspected finding. The surgery was postponed or canceled in five patients (0.8%) because of the abnormal x-ray results.

Adolescent↗
PubMed1993

Congenital cataract in the right eye and primary clinical anophthalmos of the left eye in a patient with cerebellar hypoplasia.

We examined a 26-year-old man who had an opaque lens OD and clinical anophthalmos OS. Low densities in the left cerebellar hemisphere and vermis and dilated ventricles were noted on a computed tomographic scan of his brain. We believe that the association of developmental cataract OD, clinical anophthalmos OS, and cerebellar hypoplasia in our patient may be rare.

Adult↗
PubMed1993

Pseudoretinitis pigmentosa in patients with systemic lupus erythematosus.

A 42-year-old woman and a 62-year-old man with systemic lupus erythematosus (SLE) had bilaterally mottled retinas with spots or clumps of pigment. Their electroretinographic responses were subnormal. Their fundi resembled those of patients with retinitis pigmentosa. The fundus lesions of our patients may have resulted from vascular occlusion associated with SLE.

Adult↗
PubMed1993

Nonpenetrating trauma in the right eye induces anterior uveitis and secondary glaucoma in the contralateral eye.

A 31-year-old woman was shot with a toy bullet OD. Intracameral cells and fibrin were found, but no penetrating wound was noticed. Flare was observed in the left anterior chamber three days after the incident, and the intraocular pressure OS had increased. No specific type of uveitis or systemic inflammatory disease was identified. We believe that bilateral uveitis was precipitated in our patient by the nonpenetrating trauma.

Adult↗
PubMed1993

Intraocular lymphoma invades the optic nerve and orbit.

A diagnosis uveitis OS was made in a 54-year-old woman; this was resistant to corticosteroid treatment. One year later, both eyes were involved. Examination of the vitreous aspirate and the results of a chorioretinal biopsy OD did not yield a correct diagnosis. Computed tomographic scanning showed orbital invasion OD. Malignant lymphoma was diagnosed after a biopsy specimen of the orbital contents was studied histopathologically. Radiotherapy and chemotherapy diminished the orbital mass and intraocular lesions. After regression of the orbital lesion, a brain tumor was found and treated with radiotherapy and chemotherapy. At age 57 years, the patient died. We believe that our patient had a rare case of intraocular lymphoma associated with orbital invasion.

Cranial Nerve Neoplasms↗
PubMed1993

Occlusion therapy of Japanese children with anisometropic amblyopia without strabismus.

We examined 38 children (20 boys and 18 girls) with anisometropic amblyopia without strabismus who had been treated with occlusion therapy. At the initial visit, their ages ranged from five to ten years. Their visual acuity scores improved after therapy, and this was unrelated to patient age. The amount of anisometropia, visual acuity at the initial visit, and compliance were related to improved visual acuity in the amblyopic eye. The visual acuity improved for six months after therapy. No further gains were detected thereafter.

Amblyopia↗
PubMed1993

Wasp sting-induced retinal damage.

A 36-year-old man was stung by a wasp OD. He became delirious and had dyspnea, ocular pain, and severely decreased visual acuity OD. A broken stinger was found in the central deep cornea. Additional ocular findings were keratitis, iritis, cataract, secondary glaucoma, and unrecordable electroretinographic responses.

Adult↗
PubMed1993

Central retinal vein occlusion in two patients with immunoglobulin G multiple myeloma associated with blood hyperviscosity.

A 69-year-old man (Patient 1) complained of anorexia, lumbago, and seeing floaters OS. The results of laboratory tests showed immunoglobulin (Ig) G lambda-type multiple myeloma associated with blood hyperviscosity. Retinal hemorrhages OD and central retinal vein occlusion OS were found. A 71-year-old woman (Patient 2) with IgG kappa-type multiple myeloma had blood hyperviscosity. Retinal microaneurysms OD and central retinal vein occlusion OS were found. We believe that our patients represent rare cases of IgG multiple myeloma associated with blood hyperviscosity and central retinal vein occlusion.

Aged↗
PubMed1992

Immunofluorescent staining and corneal sensitivity in patients suspected of having herpes simplex keratitis.

We examined immunofluorescent staining and corneal sensitivity in 25 control subjects (25 eyes) with normal corneas, six patients (eight eyes) with possible herpes simplex keratitis, and 44 patients (48 eyes) with corneal lesions (recurrent erosion, superficial punctate keratitis, marginal ulcer, and follicular keratoconjunctivitis) in whom herpes simplex keratitis was not suspected. On immunofluorescent staining, all 25 control subjects had negative reactions, all eight eyes suspected of having herpes simplex keratitis had positive reactions, and 11 (23%) of the 48 eyes not suspected of having herpes simplex keratitis had positive reactions; the remaining 37 eyes had negative reactions. Of the 11 eyes not suspected of having herpes simplex keratitis but that had positive reactions on immunofluorescent staining, nine had recurrent erosions and the remaining two eyes had superficial punctate keratitis. Of the eight eyes with possible herpes simplex keratitis, seven (88%) had decreased corneal sensitivity. Of the 11 eyes not suspected of having herpes simplex keratitis but that had positive reactions on immunofluorescent staining, eight (73%) had decreased corneal sensitivity. Of the 37 eyes not suspected of having herpes simplex keratitis that had negative reactions on immunofluorescent staining, 11 (30%) had decreased corneal sensitivity.

Adult↗
PubMed1992

Posterior chamber intraocular lens implantation in a patient with oculocutaneous albinism.

A 56-year-old woman with tyrosinase-negative oculocutaneous albinism complained of gradually decreasing vision in the left eye. Her visual acuity was 20/300 in the right eye and hand motion in the left eye. She had pink skin and white hair and cilia. On examination, bilateral hypopigmented irides, an opaque lens in the left eye, a hypopigmented fundus in the right eye, and nystagmus were found. An extra-capsular cataract extraction with posterior chamber intraocular lens (IOL) implantation was performed. After retrobulbar anesthesia was administered, the nystagmus ceased temporarily. Postoperatively, visual acuity in the left eye improved to 20/200. We believe IOL implantation is useful in the treatment of cataracts in albino patients.

Albinism, Oculocutaneous↗
PubMed1992

Superficial punctate keratopathy and bacterial growth in patients with unilateral aphakia using extended-wear soft contact lenses.

We prospectively examined corneal conditions and bacterial growth in 77 individuals with unilateral aphakia who were using extended-wear soft contact lenses. The ratios of positive bacterial growth (70.6-79.4%) from 34 patients with superficial punctate keratopathy were significantly higher than those (41.9-46.5%) from the 43 subjects with normal corneas. Bacterial growth was found frequently in patients with superficial punctate keratopathy who were older than 80 years and in those using soft contact lenses for more than 22 days. Several kinds of bacteria grew from the specimens. Among the most common were Staphylococcus epidermidis and Corynebacterium species. Pseudomonas aeruginosa grew from patients with superficial punctate keratopathy who were using extended-wear soft contact lenses.

Aged↗