Biomedical subjects

S Hayasaka

Publications and source records attributed to S Hayasaka.

At least 343 records · Page 19Linked to original sources

PubMedDate not supplied

Effects of tetramethylpyrazine on prostaglandin E(2)- and prostaglandin E(2) receptor agonist-induced disruption of blood-aqueous barrier in pigmented rabbits.

PURPOSE: To evaluate the effect of tetramethylpyrazine on the elevation of aqueous flare and intraocular pressure (IOP) induced by prostaglandin (PG) E(2) and PGE(2) receptor (EP) agonists. METHODS: PGE(2) or EP agonists (11-deoxy PGE(1), EP(2) agonist; 17-phenyl trinor PGE(2), EP(1) and EP(3) agonist; or sulprostone, EP(1) and EP(3) agonist), 25 microg/mL, were transcorneally administered to pigmented rabbits. Animals were pretreated with tetramethylpyrazine intravenously (10 or 30 mg/kg) or topically (0.1% solution). Aqueous flare was measured using a laser flare-cell meter, and the intensity was expressed as the area under the curve (AUC). Intraocular pressure was measured using a noncontact tonometer. RESULTS: After administration of PGE(2), aqueous flare and IOP increased and then gradually decreased. The AUC of eyes pretreated with tetramethylpyrazine, 10 or 30 mg/kg, intravenously, or topical 0.1% solution, was significantly smaller than that of the controls. The mean Delta IOP of eyes pretreated with tetramethylpyrazine, 30 mg/kg intravenously, was significantly lower than that of the controls. After administration of 11-deoxy PGE(1), aqueous flare increased and then gradually decreased. 17-phenyl trinor PGE(2) and sulprostone did not disrupt the blood-aqueous barrier. The AUC of eyes pretreated with tetramethylpyrazine, 10 or 30 mg/kg, intravenously, before 11-deoxy PGE(1) application was significantly smaller than that of the controls. CONCLUSION: The results indicated that tetramethylpyrazine inhibited PGE(2)- or 11-deoxy PGE(1)-induced elevation of aqueous flare and IOP.

Alprostadil↗

PubMedDate not supplied

Effects of scutellariae radix extract and its components (baicalein, baicalin, and wogonin) on the experimental elevation of aqueous flare in pigmented rabbits.

PURPOSE: To evaluate the possible inhibitory effects of hot water extract of Scutellariae radix and its major components (baicalein, baicalin, and wogonin) on experimental elevation of aqueous flare in pigmented rabbits. METHODS: To produce aqueous flare elevation in rabbits, prostaglandin E(2) (PGE(2)), 25 microg/mL, was applied to the cornea with the use of a glass cylinder, or lipopolysaccharides (LPS), 0.5 microg/kg, were injected into an ear vein. Animals were pretreated by the oral administration of 150 g/day of food containing 0.02%, 0.07%, or 0.2% (w/w) extract of Scutellariae radix for 5 days, or by intravenous injection of baicalein, baicalin, or wogonin, 60 microg/kg or 600 microg/kg, 30 minutes before experimental uveitis was induced. Aqueous flare was measured with a laser flare-cell meter. Aqueous flare intensity was expressed as the area under the curve (AUC) in arbitrary units. RESULTS: The AUC of PGE(2)- and LPS-induced aqueous flare elevation was 1,343 and 5,066 arbitrary units, respectively. Pretreatment by oral administration of 0.07% or 0.2% extract of Scutellariae radix did not inhibit PGE(2)-induced aqueous flare elevation (AUC: 1,252 and 1,210, respectively), but it did inhibit LPS-induced aqueous flare elevation (AUC: 2,248 and 1,973, respectively). Pretreatment by intravenous injection of 600 microg/kg of baicalein, baicalin, or wogonin inhibited LPS-induced aqueous flare elevation (AUC: 2,289, 2,163, and 1,509, respectively). Pretreatment with 60 microg/kg of wogonin also inhibited LPS-induced aqueous flare elevation (AUC: 1,980). CONCLUSION: Hot water extract of Scutellariae radix may have an inhibitory effect on experimental anterior uveitis induced by LPS in pigmented rabbits.

Animals↗

PubMedDate not supplied

Peripherin/RDS gene mutation (Pro210Leu) and polymorphisms in Japanese patients with retinal dystrophies.

PURPOSE: To determine the frequency of peripherin/RDS (retinal degeneration slow) gene mutations in Japanese patients with retinal dystrophies. METHODS: We analyzed the peripherin/RDS gene in 54 unrelated Japanese patients with retinal dystrophies. Genomic DNA was amplified by polymerase chain reaction (PCR) and the PCR products were sequenced. We also examined 100 healthy subjects, seeking mutations or variations of the peripherin/RDS gene. RESULTS: Of the 54 Japanese patients, one with retinitis pigmentosa had a heterozygous C to T change at the second nucleotide at codon 210 of exon 2 (CCT to CTT/Pro210Leu) of the peripherin/RDS gene. None of the 100 individuals with normal fundi had the Pro210Leu mutation of the peripherin/RDS gene. Three variants of the peripherin/RDS gene (GTC to GTT/Val106Val, Glu304Gln, and Gly338Asp) were also found. The first variation (GTC to GTT/Val106Val) was silent. Two concurrent missense variations (Glu304Gln and Gly338Asp) were seen in 25.9% of the affected patients and in 29% of the healthy individuals. CONCLUSION: A novel mutation (Pro210Leu) of the peripherin/RDS gene has been found in one Japanese patient with retinitis pigmentosa. The alterations of Val106Val, Glu304Gln, and Gly338Asp may be polymorphic variants in the Japanese population.

DNA Mutational Analysis↗

PubMedDate not supplied

Unilateral symptomatic elevation of intraocular pressure and prevention using a hyperosmotic agent during hemodialysis.

BACKGROUND: We report on a patient with unilateral elevation of intraocular pressure during hemodialysis. CASE: A 60-year-old man with unilateral exfoliative material complained of severe pain in the right eye during hemodialysis. OBSERVATIONS: The intraocular pressure (IOP) in the patient's right eye was 56 mm Hg, and increased repeatedly during hemodialysis. The IOP in his left eye remained within a normal range. Trabeculectomy failed to reduce the elevation of IOP in the right eye. Changes in plasma osmotic pressure during hemodialysis were marked when the IOP was elevated. The administration of a hyperosmotic agent prevented the elevation of IOP during hemodialysis. CONCLUSIONS: Physicians should be aware that elevation of IOP in patients with eyes with exfoliative material may occur during hemodialysis even after trabeculectomy. This can be prevented by administering a hyperosmotic agent during hemodialysis.

Diuretics, Osmotic↗

PubMedDate not supplied

Double-ring and double-layer sign of the anterior lens capsule during cataract surgery.

BACKGROUND: Splitting of the lens capsule with a double-ring contour during continuous curvilinear capsulorrhexis has not often been reported. CASE: An 86-year-old woman underwent phacoemulsification cataract extraction with intraocular lens implantation in the right eye. Preoperatively, the anterior lens capsule appeared normal. OBSERVATIONS: A double-ring sign was observed during capsulorrhexis. During intraocular lens implantation, the capsule developed radial tears, and a double layer of the capsule was noted. The patient's postoperative course was uneventful. CONCLUSIONS: The findings in our patient may be uncommon and may differ from but resemble true exfoliation.

Aged↗

PubMedDate not supplied

Effect of topical betaxolol on acute rise of aqueous flare induced by prostaglandin E(2) in pigmented rabbits.

PURPOSE: To evaluate the effects of topical betaxolol on experimental ocular inflammation. METHODS: Transcorneal diffusion of 25 microg/mL (7.09 x 10(-2) mmol/L) of prostaglandin E(2) (PGE(2)), placed in a glass cylinder, was employed to induce aqueous flare elevation in pigmented rabbits. Betaxolol was administered topically before PGE(2) application. Aqueous flare was measured with a laser flare cell meter. RESULTS: Four-, two-, and one-time topical instillations of betaxolol inhibited the PGE(2)-induced aqueous flare elevation by 44% +/- 8%, 32 +/- 7%, and 8 +/- 6%(mean +/- SD), respectively. The inhibition of flare elevation was dependent on the number of betaxolol instillations. CONCLUSION: Topical betaxolol has an inhibitory effect on PGE(2)-induced aqueous flare elevation in rabbit eyes.

Acute Disease↗

PubMedDate not supplied

Conjunctival injection, episcleral vessel dilation, and subconjunctival hemorrhage in patients with new tsutsugamushi disease.

Tsutsugamushi disease is found in two types: classical and new. There have been very few reports describing the ocular findings in patients with the new form. We have described four patients with this type, selected according to their clinical and laboratory findings, including immunofluorescent titers and polymerase chain reaction results. Eyes were examined by standard ophthalmic procedures. Patient 1 had bilateral conjunctival injection and subconjunctival hemorrhage; patients 2-4 had conjunctival injection and episcleral vessel dilation bilaterally. We believe that conjunctival injection is found in most eyes of patients with new tsutsugamushi disease.

Adult↗

PubMedDate not supplied

Orbital lymphoma of mucosa-associated lymphoid tissue in a patient with rheumatoid arthritis.

A 75-year-old male with rheumatoid arthritis complained of proptosis of the left eye. On examination, 6-mm left proptosis was seen. A hyperemic and swollen optic disc was visible in the left fundus. Laboratory test results showed positive rheumatoid factor. Computed tomography and magnetic resonance imaging showed a mass lesion in the left orbit. Histopathologic study of the excised specimen revealed centrocyte-like cells and lymphoplasmocytoid cells. Immunohistochemical study showed positive staining of CD 20 (B cells) and lambda light chain (immunoglobulin). The combination of rheumatoid arthritis and lymphoma of mucosa-associated lymphoid tissue in the orbit, as demonstrated in our patient, is rare.

Aged↗

PubMedDate not supplied

Methicillin-resistant Staphylococcus aureus and methicillin-resistant coagulase-negative staphylococci from conjunctivas of preoperative patients.

To evaluate the incidence and characteristics of carriers of conjunctival methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant coagulase-negative Staphylococci (MRCNS) among preoperative patients at an eye clinic, bacterial growth was studied in 978 conjunctival specimens of 628 preoperative patients without signs of ocular infection. Specimens were evaluated for growth of bacteria on nutrient agar plate, blood agar plate, or chocolate agar plate for 2 days at 37 degrees C. Methicillin resistance was confirmed by disk diffusion and agar screening methods. Susceptibilities of the bacterial strain to ampicillin (ABPC), cefazolin (CEZ), minocycline (MINO), gentamicin (GM), erythromycin (EM), vancomycin (VCM), and ofloxacin (OFLX) were determined by the disk diffusion method. Of the 628 patients (978 eyes), 352 patients (580 eyes) had positive bacterial growth. Among them, 8 (13 eyes) had MRSA growth and 2 (4 eyes) had MRCNS growth. The rate of nasolacrimal duct obstruction was significantly higher in eyes with positive bacterial growth than in eyes with negative growth. Of the 10 patients (17 eyes) with MRSA or MRCNS growth, 8 were older than 80 years, 5 had the same bacterial strains in the anterior nares and throat, 6 had nasolacrimal duct obstruction, 3 had dry eye, and 9 had been recently hospitalized. All 10 bacterial strains were resistant to ABPC, CEZ, and EM, but were sensitive to MINO and OFLX. Five strains were resistant and 5 were sensitive to GM. Two strains examined were sensitive to VCM. After topical antibiotic use for 0.5 to 6 months, the bacterial strains were eliminated. Two of the 17 eyes with MRSA or MRCNS growth did not undergo surgery. No postoperative endophthalmitis developed in 976 of the 978 eyes. Ophthalmologists should be aware that about 50% of preoperative patients without signs of ocular infection may have bacterial growth on the conjunctiva, and that elderly patients with nasolacrimal duct obstruction, dry eye, and recent hospital stays may be carriers of MRSA or MRCNS.

Adolescent↗

PubMedDate not supplied

Effects of Kakkon-to and Sairei-to on experimental elevation of aqueous flare in pigmented rabbits.

PURPOSE: To evaluate the possible inhibitory effects of Kakkon-to and Sairei-to, traditional Sino-Japanese herbal medicines, on experimental aqueous flare elevation in pigmented rabbits. METHODS: Anterior uveitis was induced either by an application of prostaglandin E2 (PGE2), 10 microg/mL, to the cornea, or an intravenous injection of lipopolysaccharides (LPS), 0.5 microg/kg, in an ear vein. Dose dependency of experimental uveitis induced by LPS (0.1, 0.25, 0.5, or 1.0 microg/kg) was also determined. For pretreatment, about 150 g/day of food containing Kakkon-to (1% w/w) or Sairei-to (0.6% or 2% w/w) was given to two groups of animals for 5 days before experimental uveitis was induced. A third group of animals underwent pretreatment with betamethasone, 130 microg/kg, injection into an ear vein 4 hours before experimental uveitis was induced. A fourth group of rabbits with no herbal medicine or betamethasone pretreatment served as controls. Aqueous flare was measured using a laser flare-cell meter. Aqueous flare intensity was expressed as the area under the curve (AUC) in arbitrary units. RESULTS: The increase in aqueous flare induced by LPS was dose-dependent. The AUC of PGE2 (10 microg/mL) and LPS (0.5 microg/mL) induced aqueous flare elevations were 1,119 and 4,950 arbitrary units, respectively. Kakkon-to (AUC, 1,055) and Sairei-to (AUC, 965) did not inhibit the aqueous flare elevation induced by PGE2. Beta-methasone did inhibit the elevation (AUC, 271). Kakkon-to (AUC, 4,495) did not suppress the aqueous flare elevation induced by LPS. Both 0.6% and 2% Sairei-to (AUC, 2,478, and 978) and beta-methasone (AUC, 443) did suppress the aqueous flare elevation induced by LPS significantly (P < .05). CONCLUSION: Sairei-to could have an inhibitory effect on experimental anterior uveitis induced by LPS.

Animals↗

PubMedDate not supplied

Seasonal allergic conjunctivitis induced by Japanese pear pollen.

PURPOSE: To evaluate the ocular findings in patients with Japanese pear (Pyrus pyrifolia Nakai) pollinosis. METHODS: Twenty-two farmers working on artificial pollination in Japanese pear orchards were examined for ocular itching, conjunctival conditions, presence of eosinophils in the conjunctival specimen, and nasal symptoms. Serum IgE antibody to Japanese pear pollen was determined in 16 farmers. RESULTS: Of the 22 subjects, 3 (Nos. 3, 4, and 13) exhibited ocular itching, conjunctival hyperemia, eosinophils in the conjunctival specimen, and positive serum IgE antibodies to Japanese pear pollen. In these patients, the conjunctivitis disappeared after treatment with topical cromoglycate. CONCLUSION: The present study demonstrated that seasonal allergic conjunctivitis may be induced by Japanese pear pollen (entomophilous flower pollen).

Adult↗

PubMedDate not supplied

Crystalline retinopathy.

A 52-year-old Japanese woman had retinal crystalline deposits with atrophy of the pigment epithelium and choriocapillaris and pigment clumps in the periphery. The patient did not have corneal crystals. The crystals were seen biomicroscopically in all layers of the retina and on the retinal vessels. The diagnosis of crystalline retinopathy was made. The progressive nature of the disease was confirmed, based on a 9-year follow-up. The authors reviewed this condition in the Japanese literature and believe that crystalline retinopathy may not be as rare in the Orient as previously thought.

Asian People↗

PubMedDate not supplied

Peripheral retinal microaneurysms in patients receiving hemodialysis.

The fundi of 55 patients receiving hemodialysis were examined. Of 55 patients, six demonstrated peripheral retinal microaneurysms. They had hemodialysis treatments three times a week for several years and showed retinal arteriosclerosis, systemic hypotension, and anemia. It is possible that these systemic conditions may produce microaneurysms in hemodialysis patients.

Adult↗

PubMedDate not supplied

Changes in deviation following correction of hyperopia in children with fully refractive accommodative esotropia.

Changes in deviation may occur following the correction of hyperopia in children with accommodative esotropia. We analyzed possible factors involving the development of changes in deviation. We examined 49 children (23 boys and 26 girls) who had fully refractive accommodative esotropia at the age of 3 or 4 years. All children wore glasses to correct the fully cycloplegic refractive errors. At the age of 10 or 11 years, 28 (57.1%) of these children had good alignment, 12 (24.5%) developed partial accommodative esotropia and 9 (18.4%) developed consecutive exotropia. The age at onset of esotropia, age at initial visit, and refraction, deviation and presence of stereopsis, as determined by the Titmus test using a fly at the initial visit, were similar among the three groups. In the consecutive exotropia group, amblyopia at the initial visit was significantly higher (89%) than that of the good alignment group (50%). The age at the start of the correction, and the refraction, amblyopia and presence of fusion (10 or 11 years) were almost equal among the three groups. We conclude that some children with fully refractive accommodative esotropia associated with amblyopia at the age of 3 or 4 years may be predisposed to developing consecutive exotropia.

Accommodation, Ocular↗

PubMedDate not supplied

Bilateral angle closure glaucoma and visual loss precipitated by antidepressant and antianxiety agents in a patient with depression.

A 71-year-old woman with depression had been treated with an antidepressant (maprotiline) and antianxiety agents (clotiazepam and alprazolam). She had previously complained of ocular pain and blurred vision. However, thorough ocular examination was not performed at those times. On examination, visual acuity was no light perception OD and hand motion OS. Intraocular pressures were 33 mm Hg OU. Moderately dilated pupils, atrophic irises, shallow anterior chambers and closed angles were seen in both eyes. Despite treatment, her visual acuity decreased to no light perception bilaterally. Psychiatrists and ophthalmologists should be aware that antidepressants and antianxiety agents can precipitate angle closure glaucoma in susceptible eyes.

Adrenergic beta-Antagonists↗

PubMedDate not supplied

Effects of nilvadipine, nicardipine and verapamil on acute rise of aqueous flare induced by iris photocoagulation or intravenous lipopolysaccharides in pigmented rabbits.

The effects of nilvadipine, nicardipine and verapamil on the acute rise of aqueous flare induced by argon laser photocoagulation of the iris or by intravenous injection of lipopolysaccharides (LPS, 0.5 microg/kg) were investigated in pigmented rabbits. Nilvadipine, nicardipine and verapamil were injected intravenously. Aqueous flare was measured with a laser flare cell meter. Following photocoagulation, aqueous flare increased, reached its maximum at 45-75 min and then decreased. After administration of LPS, aqueous flare increased, reached its maximum at 4 h and then returned to baseline levels at about 24 h. Flare reactions were inhibited by nilvadipine in a dose-dependent manner. The elevations were maximally inhibited by nilvadipine 30 min before photocoagulation or intravenous LPS. Two hundred micrograms per kilogram of nilvadipine inhibited 81% of photocoagulation-induced flare elevation, while the same dose of nicardipine and verapamil inhibited 19 and 9% of the elevation, respectively. The same dose of nilvadipine inhibited 51% of LPS-induced flare elevation, while the same dose of nicardipine and verapamil inhibited 6 and 4% of the elevation, respectively. In conclusion, nilvadipine inhibited the experimental elevation of aqueous flare more effectively than did nicardipine and verapamil.

Acute-Phase Reaction↗

PubMedDate not supplied

Effects of topical clonidine on prostaglandin-E(2)-induced aqueous flare elevation in pigmented rabbits.

We evaluated the role of topical clonidine on experimental ocular inflammation. Transcorneal diffusion of prostaglandin (PG) E(2), 7. 09 x 10(-2) mmol/l, with the use of a glass cylinder was employed to produce aqueous flare elevation in pigmented rabbits. Clonidine was topically administered and yohimbine was injected intravenously. Aqueous flare was measured with a laser flare cell meter. Topical instillation of 0.25% clonidine inhibited 89% of PGE(2)-induced aqueous flare elevation. Instillation of clonidine at 60 or 30 min before and 10 min after PGE(2) inhibited flare significantly. Pretreatment with intravenous yohimbine decreased the clonidine-induced inhibition of the flare elevation in a dose-dependent manner. It is possible that the anti-inflammatory action of topical clonidine may be mediated partly by alpha(2)-receptors.

Acute-Phase Reaction↗

PubMedDate not supplied

Serum methanol levels in subjects with or without optic nerve head disease.

We evaluated serum methanol levels in subjects with or without optic nerve head disease. Serum methanol levels were determined using gas chromatography in 71 patients with optic nerve head disease and in 127 subjects without optic nerve head disease. Their ages ranged from 17 to 89 years. Serum methanol levels in 127 subjects without optic nerve head disease ranged from 0.12 to 3.86 microg/ml (mean +/- standard deviation, 1.72 +/- 0.86 microg/ml). In the subjects without optic nerve head disease, the differences in the levels between those with cataract versus retinal detachment, men versus women, and between each age-group (50-80 years) were not significant. The methanol levels in patients with optic neuritis (n = 2), Wolfram syndrome (n = 1), Leber hereditary optic neuropathy at the late stage (n = 2), retinitis pigmentosa (n = 23), and primary open-angle glaucoma (n = 16) were less than 3.86 microg/ml. Methanol levels in 1 patient with Leber hereditary optic neuropathy at the acute stage was 5.28 microg/ml. Of 10 patients with primary angle-closure glaucoma, 1 had a slightly elevated level and 9 had levels less than 3.86 microg/ml. Of 17 patients with normal tension glaucoma, 5 had methanol levels higher than 3.86 microg/ml, and 12 patients had levels less than 3.86 microg/ml. The present study shows that serum methanol levels in subjects without optic nerve head disease ranged from 0.12 to 3.86 microg/ml and were much lower than the levels that produce acute ocular symptoms of methanol intoxication. It is possible that high serum methanol levels may play a part in the acute stage of Leber hereditary optic neuropathy and normal tension glaucoma in certain patients. It is unlikely that increased serum methanol levels participate in primary angle-closure glaucoma.

Adolescent↗