Biomedical subjects

Shiro Amano

Publications and source records attributed to Shiro Amano.

At least 19 recordsLinked to original sources

PubMed2007

Retinal vasculitis and vitreous hemorrhage associated with mixed connective tissue disease: retinal vasculitis in MCTD.

BACKGROUND: Retinal vasculitis associated with mixed connective tissue disease (MCTD) has rarely been reported in the literature. We describe a rare case of a patient with serious retinal vasculopathy and vitreous hemorrhages associated with MCTD. CASE: A 53-year-old woman with MCTD who has had recurrent retinal vasculitis and vitreous hemorrhage in the right eye since 2000 presented with blurred vision in the right eye in April 2003. The best-corrected visual acuity was counting finger in the right eye. The patient was clinically diagnosed as having retinal and vitreous hemorrhages and retinal infarction. Prednisolone was administered orally in a daily dose of 20 mg. RESULTS: The retinal and vitreous hemorrhage improved in 7 days. The best-corrected visual acuity improved to more than 20/20 on prednisolone alone. CONCLUSION: MCTD can be associated with retinal vasculitis and vitreous hemorrhage which in our case responded well to systematic low doses of corticosteroid therapy.

Adult↗

PubMed2006

UV absorption in human oral mucosal epithelial sheets for ocular surface reconstruction.

BACKGROUND: Ocular surface reconstruction with autologous oral mucosal epithelium has attracted attention as a novel treatment strategy that avoids allograft rejection. OBJECTIVES: To evaluate the absorption of ultraviolet (UV) A or B irradiation by human oral mucosal epithelium cultured on human amniotic membrane. METHODS: Human oral mucosal and limbal epithelial cells were co-cultured on amniotic membrane with inactivated 3T3 fibroblasts. The cell sheets were also subjected to UV-A (365 nm) or UV-B (302 nm) irradiation at energy levels ranging from 50 to 800 microW/cm2, and the UV absorption rate was measured with a UV irradiation meter. RESULTS: Cultured oral mucosal epithelium had a structure with 3-5 layers of cells, consistent with the histological features of cultured corneal limbal epithelium after 4 weeks. The decrease in UV-A absorption of cultivated oral mucosal epithelium ranged from 25 to 36% of that for cultured corneal epithelium. The increase in UV-B absorption by cultured oral mucosal epithelium between 200 and 800 microW/cm2 was approximately 145% of that for cultured corneal limbal epithelium. CONCLUSION: Our data demonstrated that cultured oral mucosal epithelium has low UV-A and high UV-B absorption capacity as compared with those of cultured corneal epithelium, suggesting that oral mucosal epithelium can compensate for UV absorption of corneal epithelium.

3T3 Cells↗

PubMed2006

Bone marrow-derived cells in normal human corneal stroma.

OBJECTIVE: To examine the normal human corneal stroma for the presence of bone marrow-derived cells. METHODS: Thirty-four corneas from donors aged 56 to 71 years were used. The stroma of the donor corneas was examined immunohistochemically by fluorescent microscopy. CD45-positive and -negative cells were separated from collagenase-digested stroma by magnetic beads, and the expression of toll-like receptor 4 was analyzed. RESULTS: CD45-positive cells were mainly found in the anterior stroma of the central and paracentral cornea as well as all stromal layers of the peripheral cornea (n = 5). These cells uniformly expressed CD11b, CD11c, CD14, and HLA-DR antigen but not CD3, CD19, CD56, or CD66, indicative of bone marrow-derived monocyte lineage cells, which can include monocytes, macrophages, or dendritic cells. CD45-positive cells isolated with magnetic beads accounted for 6.0% of total stromal cells (n = 20). Stromal CD45-positive cells, but not CD45-negative cells, expressed toll-like receptor 4 by flow cytometry and reverse-transcriptase polymerase chain reaction. CONCLUSION: Our findings demonstrate that DR antigen-positive bone marrow-derived monocyte lineage cells exist in the anterior and peripheral posterior stroma of normal human cornea. Clinical Relevance These cells may play a role in the innate and adaptive immune responses in the human cornea.

Aged↗

PubMed2006

Ocular manifestations of congenital insensitivity to pain with anhidrosis.

PURPOSE: To describe ocular manifestations in Japanese patients with congenital insensitivity to pain with anhidrosis (CIPA), focusing particularly on the status of the ocular surface. DESIGN: Observational case series. METHODS: Eighteen patients with CIPA underwent applicable ophthalmologic examinations, including visual acuity, refraction, slit-lamp examination, fundus examination, tear breakup time, Schirmer 1 test, corneal sensitivity, and corneal topography. RESULTS: Superficial punctate keratopathy (SPK) was observed at the interpalpebral area in 23 (64%) of 36 eyes. Corneal opacity was observed in three eyes (8.3%). Tear breakup time was below the lower limit of the normal range in all examined eyes, and the value of Schirmer 1 test was above the lower limit of the normal range in most of the examined eyes. CONCLUSIONS: Superficial punctate keratopathy is observed in most cases of CIPA, which might predispose patients to corneal infection. Investigation of dry eye in patients with CIPA will provide unique opportunities to explore the critical roles of the autonomic sympathetic nervous system as well as the sensory nervous system in the physiology of tear production.

Adolescent↗

PubMed2006

Comparison of central corneal thickness measurements by rotating Scheimpflug camera, ultrasonic pachymetry, and scanning-slit corneal topography.

PURPOSE: To compare central corneal thickness measurements and their reproducibility when taken by a rotating Scheimpflug camera, ultrasonic pachymetry, and scanning-slit corneal topography/pachymetry. DESIGN: Experimental study. PARTICIPANTS: Seventy-four eyes of 64 subjects without ocular abnormalities other than cataract. METHODS: Corneal thickness measurements were compared among the 3 methods in 54 eyes of 54 subjects. Two sets of measurements were repeated by a single examiner for each pachymetry in another 10 eyes of 5 subjects, and the intraexaminer repeatability was assessed as the absolute difference of the first and second measurements. Two experienced examiners took one measurement for each pachymetry in another 10 eyes of 5 subjects, and the interexaminer reproducibility was assessed as the absolute difference of the 2 measurements of the first and second examiners. MAIN OUTCOME MEASURES: Central corneal thickness measurements by the 3 methods, absolute difference of the first and second measurements by a single examiner, absolute difference of the 2 measurements by 2 examiners, and relative amount of variation. RESULTS: The average measurements of central corneal thickness by a rotating Scheimpflug camera, scanning-slit topography, and ultrasonic pachymetry were 538+/-31.3 microm, 541+/-40.7 microm, and 545+/-31.3 microm, respectively. There were no statistically significant differences in the measurement results among the 3 methods (P = 0.569, repeated-measures analysis of variance). There was a significant linear correlation between the rotating Scheimpflug camera and ultrasonic pachymetry (r = 0.908, P<0.0001), rotating Scheimpflug camera and scanning-slit topography (r = 0.930, P<0.0001), and ultrasonic pachymetry and scanning-slit topography (r = 0.887, P<0.0001). Ultrasonic pachymetry had the smallest intraexaminer variability, and scanning-slit topography had the largest intraexaminer variability among the 3 methods. There were similar variations in interexaminer reproducibility among the 3 methods. CONCLUSIONS: Mean corneal thicknesses were comparable among rotating Scheimpflug camera, ultrasonic pachymetry, and scanning-slit topography with the acoustic equivalent correction factor. The measurements of the 3 instruments had significant linear correlations with one another, and all methods had highly satisfactory measurement repeatability.

Adult↗

PubMed2006

Atelocollagen punctal occlusion in dry eye patients.

PURPOSE: To evaluate the efficacy and safety of atelocollagen punctal occlusion for dry eye patients. DESIGN: Prospective noncomparative interventional case series. METHODS: Atelocollagen was injected into the superior and inferior canaliculi of 52 eyes of 28 dry eye patients. Vital staining of the ocular surface, breakup time of tears (BUT), tear volume, and corneal epithelial permeability to fluorescein were examined before and 1, 2, 4, and 8 weeks after treatment. RESULTS: Rose bengal stain, fluorescein stain, BUT, and corneal epithelial permeability to fluorescence were significantly improved 1 week after atelocollagen punctal occlusion, and the improvement was maintained for up to 8 weeks after treatment. CONCLUSIONS: Atelocollagen punctal occlusion effectively improves ocular surface disorders in dry eye patients.

Adult↗

PubMed2006

Detection of Streptococcus species by polymerase chain reaction in infectious crystalline keratopathy.

PURPOSE: Investigation of a positive polymerase chain reaction (PCR) for Streptococcus species from an excised cornea of a patient with infectious crystalline keratopathy. METHODS: Samples microdissected from corneal intrastromal aggregates present in infectious crystalline keratopathy were subjected to PCR for 3 primer pairs respectively specific for Streptococcus, Staphylococcus, and several kinds of fungi. RESULTS: The PCR detected DNA from Streptococcus but not from Staphylococcus or fungi. Direct sequencing of the PCR products showed that the PCR products had the highest identity (99.8%) with Streptococcus mitis and Streptococcus gordoni, indicating that these species were the most probable causes of infectious crystalline keratopathy in this patient. CONCLUSION: Our findings suggest that PCR provides a good adjunct technique in the diagnosis of corneal infection.

Aged↗

PubMed2006

Corneal stromal and endothelial cell precursors.

PURPOSE: To isolate precursors of human corneal stromal and endothelial cells in vitro and to compare the distribution of rabbit corneal endothelial cell precursors in the central and peripheral regions of the cornea. METHODS: Sphere-forming cells were isolated from human corneal stromal and endothelial cells by a reaggregation-free neurosphere assay. To promote differentiation of the cells, the isolated sphere colonies were plated in wells with a medium containing fetal bovine serum. Expression of various proteins was examined in the sphere colonies and their progeny by immunocytochemistry and reverse-transcriptase polymerase chain reaction (RT-PCR). Corneal endothelium and Descemet membrane of rabbits were demarcated into peripheral (6.0-10.0 mm in diameter) and central (6.0 mm in diameter) regions. Precursor cells were isolated from these 2 regions by sphere-forming assay, and the number of sphere colonies and size of spheres were compared in the central and peripheral regions. RESULTS: Human corneal stromal and endothelial cells formed sphere-shaped colonies that expressed mesenchymal and neural markers. The rate of sphere formation in the peripheral region of rabbit corneal endothelium was significantly higher than that in the central cornea. CONCLUSION: Adult human corneal stroma contains precursor cells that have a strong propensity to differentiate into mesenchymal fibroblasts, but these cells can also differentiate into neuronal lineage. Adult human corneal endothelium contains precursors with a propensity to differentiate into corneal endothelial cells, but these cells can also produce neuronal and mesenchymal cell proteins. The peripheral endothelium of rabbit cornea contains more precursors than the central region.

Animals↗

PubMed2006

Isolation of human corneal endothelial cell precursors and construction of cell sheets by precursors.

PURPOSE: To review recently published experimental data on human corneal endothelium (CE) precursors. METHODS: A sphere-forming assay was used for the isolation of human CE precursors from human donor corneas and cultured human CE. CE morphology derived from precursors was compared with that from cultured human CE. RESULTS: Human CE from donor corneas formed primary and secondary sphere colonies and expressed neural and mesenchymal proteins. The progeny of these colonies had a human-CE-like hexagonal shape and showed transport activity, suggesting that the isolated spheres were indeed precursors of human CE. Similar precursors were isolated from cultured human CE, which provided further evidence that the sphere-forming assay facilitates the mass production of human CE precursors. Cultured human CE obtained in this manner had a regular hexagonal morphology in contrast to passaged, cultured human CE. CONCLUSION: The sphere-forming assay may become a powerful tool for the regeneration of human CE by precursor injection and the construction of cultured CE sheets.

Adult Stem Cells↗

PubMed2006

Topical ocular drug delivery to inner ear disease and sinusitis.

Oral steroids are the main therapy for sensorineural deafness. We present the rare case of a patient whose hearing loss associated with inflammation of the inner ear and chronic sinusitis were improved with topical steroid therapy. A 68-year-old male presented with scleritis in the left eye, inflammation of the inner ear and chronic sinusitis. He received oral prednisolone 10 mg/d. However, the oral prednisolone was discontinued due to severe side effects. Topical administration of 0.1% betamethasone sodium phosphate improved the scleritis and incidentally also relieved his symptoms of recurrent otitis and sinusitis after several days. Audiometry revealed recovered acoustic sensation in the right ear, from 50 dB to 20 dB, and in the left ear from 70 to 35 dB with 1,000 Hz. Topical ocular drug delivery of steroids may be effective for inner ear disease and sinusitis in patients with systemic side effects to oral steroids.

Aged↗

PubMed2006

Optic disc and retinal nerve fiber layer analysis with scanning laser tomography after LASIK.

PURPOSE: To examine whether LASIK induces changes in the optic disc and retinal nerve fiber layer using scanning laser tomography. METHODS: Prospective, consecutive study of 53 myopic eyes in 38 patients (mean age: 35.7 +/- 10.4 years; range: 22 to 58 years). Preoperative average refractive error was -6.0 +/- 2.4 diopters (D) (spherical equivalent) (range: -2.0 to -10.0 D). Optic disc morphology and retinal nerve fiber layer thickness were evaluated with scanning laser tomography preoperatively and at 7 and 13 months postoperatively. RESULTS: No statistically significant differences were noted between the pre- and postoperative optic disc and retinal nerve fiber layer measurements. CONCLUSIONS: Our results suggest that transient extreme elevation of intraocular pressure during LASIK does not affect the optic disc morphology or retinal nerve fiber layer thickness in normal myopic eyes for at least 1 year after surgery.

Adult↗

PubMed2005

Glutamic acid decarboxylase autoantibody prevalence and association with HLA genotype in patients with younger-onset type 1 diabetes and proliferative diabetic retinopathy.

OBJECTIVE: To investigate the relationship of HLA status and autoantibodies to glutamic acid decarboxylase (GAD) in proliferative diabetic retinopathy (PDR) to assess the role of autoimmunity and genetic markers in retinopathy. DESIGN: Retrospective, nonrandomized, comparative study. PARTICIPANTS: Patients who had suffered from type 1 diabetes for >10 years and who had been first diagnosed as diabetic under 30 years of age were studied. They were classified into 3 groups: 20 patients with diabetes and PDR (PDR group), 22 patients who had diabetes and severe nonproliferative diabetic retinopathy (SNPDR group), and 25 patients who had diabetes with no diabetic retinopathy (non-DR group). METHODS: Blood was collected, and the relationship between HLA status and GAD autoantibody positivity in diabetic retinopathy was investigated in a cross-sectional study. MAIN OUTCOME MEASURES: Human leukocyte antigen status and GAD autoantibody positivity. RESULTS: The highest positive rate of GAD autoantibody was 56.0% in the non-DR group, followed by the SNPDR group (40.1%) and the PDR group (15.0%). The frequencies of the HLA-DQ4 and -DR4/-DQ4 haplotypes were significantly higher in the PDR group (75.0% and 65%, respectively) than in the SNPDR group (40.9% and 31.8%) or the non-DR group (40.0% and 28.0%) (P = 0.035 and P = 0.026, respectively). The prevalence of GAD antibodies was lower in patients with the HLA-DR4 and HLA-DQ4 alleles and -DR4/-DQ4 haplotype frequencies in the PDR group (P = 0.018, P = 0.0088, and P = 0.0031, respectively). CONCLUSIONS: We found that the existence of GAD antibodies is inversely related and HLA status is directly related to the stage or severity of retinopathy.

Adolescent↗

PubMed2005

Immunohistochemical localization of advanced glycation end products in pinguecula.

BACKGROUND: Advanced glycation end products (AGEs) are known to be deposited in the target organ of ageing. In addition, the deposition of AGEs accelerate the process of ageing. We investigated the immunohistochemical localization of AGEs in pinguecula, one of the ocular changes related with ageing process. METHODS: Surgical specimens of conjunctiva with or without pinguecula were prepared from nine patients, respectively. Immunohistochemical localization of AGEs was investigated using monoclonal antibodies to N(epsilon)-(carboxymethyl)lysine, pentosidine, imidazolone, and pyrraline. RESULTS: Moderate to strong immunoreactivities to AGEs were detected in the subepithelial amorphous deposits of all the surgical specimens with pinguecula. In contrast, no or weak immunoreactivities to AGEs were detected in the surgical specimens without pinguecula. CONCLUSIONS: Pinguecula is an aggregation of AGEs-modified proteins. The presence of pinguecula would be an index of local irradiation of ultraviolet rays and decreased antioxidant activities.

Adult↗

PubMed2005

Topical application of culture supernatant from human amniotic epithelial cells suppresses inflammatory reactions in cornea.

Human amniotic epithelial cells (HAEC) may be a source of soluble anti-inflammatory factors. The purpose of this study is to determine the effect of topically applied HAEC culture supernatant on corneal inflammatory reactions. HAEC were obtained from a placenta and cultured for 48 hr, and the supernatant was collected. The conditioned medium from HAEC contained small amounts of human interleukin-1 receptor antagonist (IL-1ra). Intrastromal sutures were placed in the cornea of BALB/c mice to induce corneal neovascularisation. Superficial cauterisation was applied to induce recruitment or activation of antigen presenting cells (APCs) in the cornea without neovascularisation. HAEC conditioned medium, placebo, or recombinant human IL-1ra was topically applied three times daily for 2 weeks. Suture-induced corneal neovascularisation was evaluated microscopically for 8 weeks. The cauterised corneas were harvested at 2 weeks, and the MHC class II(+) APCs were quantified by immunofluorescent staining and confocal microscopy. Inflammatory cytokine gene expression in the cauterised corneas was analyzed by a multiprobe ribonuclease protection assay. Conditioned medium from HAEC led to a profound suppression of corneal neovascularisation and fewer MHC class II(+) APCs in the epithelium. In contrast, human IL-1ra was only slightly effective in suppressing corneal inflammatory reactions. mRNA expression of murine IL-1ra and IL-1beta in the cauterised corneas was markedly suppressed after application of the conditioned medium. These results suggest that HAEC are a source of soluble anti-inflammatory factors and that conditioned medium from HAEC contains factors other than IL-1ra that suppress corneal inflammation.

Administration, Topical↗

PubMed2005

Long-term outcome of iron-endocytosing cultured corneal endothelial cell transplantation with magnetic attraction.

The long-term efficacy and safety of transplanting iron-endocytosing cultured corneal endothelial cells (CECs) with magnetic attraction were evaluated. Rabbit corneas were subjected to cryo-injury to detach CECs. Cultured rabbit CECs (RCEC) were exposed to spherical iron powder and then injected into the anterior chamber, after which a neogium magnet was fixed on the eyelid for 24 hr to attract the cells to Descemet's membrane (RCEC-iron group, n=4). An RCEC group (cryo-injury and injection of normal cultured RCEC, n=4) and a Cryo group (cryo-injury without injection of RCEC, n=4) served as controls. Intraocular pressure was measured for 12 months after surgery. Corneal findings on slit lamp biomicroscopy, RCEC density, the electro-retinogram (ERG), and residual iron in the ocular tissues were evaluated at final assessment. Intraocular pressure did not increase in any group throughout 12 months of observation. At the final assessment, the average corneal edema score of the RCEC-iron group was significantly lower than that of the RCEC or Cryo groups (p=0.021). The average CEC density of the RCEC-iron group was 2581+/-230 cells mm(-2) (mean+/-SD), whereas no CECs were observed on the inner surface of the central cornea in the RCEC and Cryo groups. No significant differences of the ERG (a- and b-wave amplitudes, and b-wave/a-wave ratio) were detected among the groups. Iron powder was not detected by Berlin blue staining in the ocular tissues of the RCEC-iron group. Apoptotic cells were not observed in the endothelium by terminal transferase-mediated nick-end labeling. Transplanted iron-endocytosing RCEC remained viable for 12 months after surgery. There were no detectable ocular complications after the transplantation of iron-endocytosing cultured RCEC. Magnetic attachment of iron-endocytosing CECs can be an effective and safe method for corneal endothelial repair.

Animals↗

PubMed2005

Late-onset repetitive traumatic flap folds and partial dehiscence of flap edge after laser in situ keratomileusis.

A 25-year-old woman had traumatic flap folds and partial dehiscence of the flap edge in the right eye 5 and 30 months after laser in situ keratomileusis. The period from injury to treatment was 4 hours and 9 days, respectively. With the first injury, the flap was lifted and stretched with moistened sponges to clear the folds. With the second injury, the folds were hard so the flap was lifted and sutured to stretch the folds. The patient recovered visual acuity within 2 weeks.

Accidents, Occupational↗

PubMed2005

Limbal allograft, amniotic membrane transplantation, and intraoperative mitomycin C for recurrent pterygium.

OBJECTIVE: To conduct a pilot study evaluating the efficacy and safety of limbal allograft, preserved amniotic membrane transplantation, and intraoperative mitomycin C treatment for recurrent pterygium. DESIGN: Prospective, noncomparative, interventional case series. PARTICIPANTS: Twelve eyes of 11 patients with recurrent pterygium. The mean number of previous surgeries for pterygium was 1.9+/-1.4 (range, 1-6). INTERVENTION: All subjects received limbal allograft, preserved amniotic membrane transplantation, and intraoperative mitomycin C. MAIN OUTCOME MEASURES: Pterygium recurrence and complications. RESULTS: The mean follow-up period was 21.6+/-5.6 months (range, 16-36 months). There was no pterygium recurrence in any of the eyes. Symblepharon reappeared in 3 eyes and diplopia recurred in 2 eyes. There were no other surgical complications and there was no graft rejection. CONCLUSIONS: Limbal allograft, preserved amniotic membrane transplantation, and intraoperative mitomycin C may be a safe and effective procedure for recurrent pterygium.

Aged↗

PubMed2005

Ultraviolet transmittance of human limbal epithelial cells cultured on human amniotic membranes.

PURPOSE: To evaluate ultraviolet (UV) A and B transmittance by human limbal epithelial cells cultured on human amniotic membranes. METHODS: Human limbal epithelial cells were taken from the limbus of donor corneas and were cultured on human amniotic membranes with inactivated 3T3 fibroblasts for 2 to 4 weeks. Then, the cultured cells were examined histologically. Next, cells from different culture periods were irradiated with UV-A (365 nm) or UV-B (302 nm) at energy levels ranging from 50 to 800 microW/cm2, and UV transmittance was measured with a UV light meter. RESULTS: Histological examination revealed a monolayer of corneal epithelial cells on the amniotic membrane after 2 weeks of culture, and a layer of 3-4 cells was formed after 4 weeks. Transmittance of UV-A and UV-B was highest by the amniotic membrane alone, followed in decreasing order by limbal epithelial cells cultured on amniotic membranes for 2 weeks, 3 weeks, and 4 weeks. CONCLUSIONS: These results indicate that UV absorbance increases in proportion to the number of limbal epithelial cell layers in cultures on amniotic membranes. Limbal epithelial cells may need to be cultured until 3-4 layers are formed in order to prevent ocular damage by UV light after transplantation.

3T3 Cells↗