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In this study, the global fiber kinking theory proposed by Budiansky and Fleck for the estimation of axial compressive strength of unidirectional carbon fiber reinforced plastic was modified for the localized fiber kinking problem. The deterministic mechanism of the compressive strength and kink-band width was interpreted using a graphical method. Carbon fiber reinforced plastic was manufactured from carbon fiber and epoxy matrix using prepreg and autoclave technology, and the axial compressive strength was measured. The nonlinear shear stress–strain curves of the composite and matrix were also measured using V-notched beam, in-plane shear, and torsion tests. The composite axial compressive strength and kink-band width were estimated based on the composite and matrix shear properties, respectively, and the estimated values were in good agreement with the experimental results.

Ryohsuke Kohmoto,1 Tetsuya Sugiyama,1 Mari Ueki,1,2 Shota Kojima,1 Michiko Maeda,1 Emika Nemoto,1 Satoru Tokuoka,3 Tsunehiko Ikeda1 1Department of Ophthalmology, Osaka Medical College, Takatsuki, Japan; 2Department of Ophthalmology, Takatsuki Red Cross Hospital, Takatsuki, Japan; 3Department of Ophthalmology, Hokusetsu General Hospital, Takatsuki, JapanCorrespondence: Ryohsuke KohmotoDepartment of Ophthalmology, Osaka Medical College, 2-7 Daigaku-machi, Takatsuki, Osaka 569-8686, JapanTel +81 72 683 1221Fax +81 72 681 8195Email ryousuke0218@hotmail.co.jpPurpose: To investigate the relationship between laser speckle flowgraphy (LSFG) and optical coherence tomography angiography (OCTA) measurements of the peripapillary retina and optic nerve head (ONH) in normal eyes and eyes with primary open-angle glaucoma (POAG).Patients and methods: One eye from each of 46 normal subjects and mild and moderate/advanced POAG patients were included. ONH blood flow acquired by LSFG, circumpapillary vessel density (cpVD, a 250 μm-wide elliptical annulus around the optic disc), and intra-papillary vessel density (ipVD, a 1.5×1.5 mm scan field) acquired by OCTA were measured. Their values were compared among normal controls and patients at each stage of glaucoma using one-way ANOVA, and the correlation between measurements obtained by the two methods was examined by univariate regression analysis.Results: ONH tissue blood flow, tissue mean blur rate (MBR-T), and cpVD in the outer layer of the retina significantly decreased with the progression of glaucoma stage, although the latter showed no significant difference between normal subjects and mild-stage glaucoma patients. MBR-T was significantly correlated with cpVD, but not with ipVD, in the retinal outer layer.Conclusion: A correlation was found only between MBR-T and cpVD in the retinal outer layer. A difference in MBR-T, but not in cpVD, was detected between normal controls and mild glaucoma patients.Keywords: optic nerve head, blood flow, laser speckle flowgraphy, optical coherent tomography angiography

Purpose To investigate whether the P2X7 receptor is involved in retinal ganglion cell (RGC) death after the intraocular pressure (IOP) is elevated in rats. Methods After the IOP was elevated to 90 mmHg for 1 h, the rats were subsequently administered oxidized adenosine triphosphate (OxATP) and brilliant blue G (BBG) as P2X7 antagonists. The rats were euthanized 7 days after IOP elevation for histologic evaluation and at 1, 3, and 7 days after IOP elevation to immunostain for the P2X7 receptor and neuron-specific class III β-tubulin in the retina. Changes in P2X7 receptor expression were measured in total retina extracts using western blot analysis. Quantitative real-time PCR was also performed using the entire retina to determine whether the P2X7 receptor is involved in upregulating tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 at 1, 2, and 3 days after the IOP was elevated. Results RGC density and the inner plexiform layer thickness significantly decreased 7 days after IOP elevation, but were dose-dependently preserved when treated with OxATP or BBG. P2X7 immunoreactivity in the RGCs increased after IOP elevation, with the peak occurring from day 1 through day 3. Protein levels of P2X7 receptor were significantly increased 1, 2, and 3 days after IOP elevation. The messenger ribonucleic acid expression of the P2X7 receptor, TNF-α, IL-1β, and IL-6 was significantly upregulated in the retina after IOP elevation, and was suppressed by treatment with OxATP. Conclusions These results suggest the expression of the P2X7 receptor is upregulated in the retina after IOP elevation, leading to RGC death. Upregulation of TNF-α, IL-1β, and IL-6 might be involved in this mechanism of RGC death. Furthermore, P2X7 antagonists may prevent RGC death after IOP elevation.

Tomoko Miyake,1 Shota Kojima,1 Tetsuya Sugiyama,2 Mari Ueki,1 Jun Sugasawa,1 Hidehiro Oku,1 Kensuke Tajiri,1 Yuka Shigemura,3 Koichi Ueda,3 Atsuko Harada,4 Mami Yamasaki,4 Takumi Yamanaka,4 Hidetsuna Utsunomiya,5 Tsunehiko Ikeda1 1Department of Ophthalmology, Osaka Medical College, Takatsuki City, 2Nakano Eye Clinic of Kyoto Medical Co-operative, Kyoto, 3Department of Plastic and Reconstructive Surgery, Osaka Medical College, Takatsuki City, 4Department of Pediatric Neurosurgery, Takatsuki General Hospital, Takatsuki City, 5Department of Radiological Science, International University of Health and Welfare, Graduate School, Fukuoka, Japan Introduction: The incidence of facial cleft is rare and ranges between 1.43 and 4.85 per 100,000 births. To date, there have been few reports of detailed ophthalmologic examinations performed in cases of facial cleft. Here, we report a case of optic-nerve hypoplasia and anterior segment abnormality associated with facial cleft. Case report: A 9-day-old female infant was delivered by cesarian section at 34 weeks of gestational age (the second baby of twins) and weighed 2,276 g upon presentation. She had a facial cleft and ectrodactyly at birth. Right eye-dominant blepharophimosis was obvious. Examination of the right eye revealed inferior corneal opacity with vascularization, downward corectopia, and optic-nerve hypoplasia. The corneal diameter was 8 mm in both eyes, and tonometry by use of a Tono-Pen® XL (Reichert Technologies, Depew, NY, USA) handheld applanation tonometer revealed that her intraocular pressure was 11–22 mmHg (Oculus Dexter) and 8 mmHg (Oculus Sinister). B-mode echo revealed no differences in axial length between her right and left eyes. When she was 15–16 months old, we attempted to examine her eyes before she underwent plastic surgery under general anesthesia. She had a small optic disc in both eyes and the right-eye disc was tilted. After undergoing canthotomy, gonioscopy and ultrasound biomicroscopy revealed that almost all directions were open except for the peripheral anterior synechia. Since magnetic resonance imaging revealed ventriculomegaly associated with an interhemispheric cyst at birth, a ventriculoperitoneal shunt was inserted at 12 days of age. At 25 months of age, her condition suddenly deteriorated due to occlusion of the ventricular shunt catheter, and she died 5 days later. In this patient, amniotic band syndrome was presumed to be the primary cause due to the clinical findings. Conclusion: We experienced a case of optic-nerve hypoplasia and anterior segment abnormality that occurred with facial cleft. The cause of these abnormalities is unclear, yet amniotic band syndrome is a possible candidate. Keywords: facial cleft, optic-nerve hypoplasia, amniotic band syndrome

Purpose To investigate the relationships among antioxidant activities, oxidative stress, and vascular endothelial growth factor (VEGF) in the vitreous body and serum from proliferative diabetic retinopathy (PDR) patients. Methods In 21 patients with PDR and 21 controls with macular hole (MH), the VEGF and lipid peroxide (Nε-hexanoyl-lysine [HEL]) levels in the vitreous and serum were measured by enzyme-linked immunosorbent assay, while antioxidant capacity (potential antioxidant [PAO]) was measured by chemical reduction of Cu2+. Results Both the PAO and HEL levels in the vitreous and serum were significantly higher in PDR patients than in those with MH (both p

Purpose To evaluate the relationship between vascular endothelial growth factor (VEGF) and extracellular superoxide dismutase (EC-SOD) in vitreous body and serum in patients with proliferative diabetic retinopathy (PDR), and investigate the role of EC-SOD in PDR by evaluating its angiostatic effect, using an in vitro angiogenesis model. To investigate the role of EC-SOD in PDR by evaluating its angiostatic effect, using an in vitro angiogenesis model. Methods EC-SOD and VEGF concentrations in vitreous and serum samples from PDR and macular hole (MH) were measured by ELISA. The effects of EC-SOD on VEGF-induced proliferation, migration, and tube formation were evaluated using human umbilical vein endothelial cells (HUVECs). Moreover, the effects of EC-SOD on VEGF-induced proliferation and migration were evaluated in HUVECs and primary normal human retinal microvascular endothelial cells. Results Intravitreal concentrations of EC-SOD were significantly higher (p

Purpose To determine the effects of mitomycin C (MMC) on the expression of chymase and mast cells in the conjunctival scar after trabeculectomy. Methods Ten eyes of five monkeys were used. Three eyes underwent trabeculectomy with MMC (MMC-treated), four eyes had trabeculectomy without MMC (placebo-treated), and three eyes served as control eyes. Intraocular pressure was measured before and three weeks after surgery. The scores of the degree of conjunctival adhesion were evaluated. Immunohistochemistry was used to analyze the densities of proliferative cell nuclear antigen-positive cells, chymase-positive cells, and mast cells. The ratio of collagen fiber areas to conjunctival and scleral lesions was analyzed by Mallory-Azan staining. Results After trabeculectomy, the intraocular pressure reduction of MMC-treated eyes was significantly different from placebo-treated and control eyes (p=0.032, 0.035). The adhesion score of MMC-treated eyes was also significantly lower than that of placebo-treated eyes (p=0.034). Densities of proliferative cell nuclear antigen-positive cells, chymase-positive cells, and areas of collagen fiber in conjunctival and scleral lesions were significantly decreased in MMC-treated eyes, compared with placebo-treated eyes (p=0.034, 0.034, 0.049, respectively). There was a tendency for the density of mast cells to be suppressed in MMC-treated eyes (p=0.157). Conclusions Chymase might be involved in one of the mechanisms by which MMC suppresses scar formation after trabeculectomy.

Masanori Fukumoto, Tsunehiko Ikeda, Tetsuya Sugiyama, Mari Ueki, Takaki Sato, Eisuke Ishizaki Department of Ophthalmology, Osaka Medical College, Takatsuki City, Japan Abstract: This case report describes a case of Alagille syndrome with developing intraocular lens subluxation and rhegmatogenous retinal detachment 4 years after cataract surgery. A 15-year-old female patient with Alagille syndrome-associated cataracts in both eyes underwent phacoemulsification aspiration and intraocular lens implantation. Four years postoperative, intraocular lens subluxation developed in her left eye. For treatment, extraction of the dislocated intraocular lens, anterior vitrectomy, and intraocular lens fixation was performed. Three weeks later, the patient developed rhegmatogenous retinal detachment, which was well-treated by pars plana vitrectomy. Cataract surgery needs to be performed carefully in patients with Alagille syndrome due to the weakness of the zonule of Zinn. Careful postoperative observation is necessary for patients with Alagille syndrome who have undergone intraocular surgery in order to facilitate early detection of a possible rhegmatogenous retinal detachment. Keywords: Alagille syndrome, cataract, retina, surgery

Michiko Miki, Mari Ueki, Tetsuya Sugiyama, Shota Kojima, Tsunehiko IkedaDepartment of Ophthalmology, Osaka Medical College, Takatsuki, JapanPurpose: To report the short-term efficacy and safety of the transfer of an Ahmed™ glaucoma valve (AGV™) tube from the vitreous into the anterior chamber, in a patient with neovascular glaucoma who had undergone pars plana AGV™ implantation and ultimately needed a silicone oil tamponade.Case: A 41-year-old male with proliferative diabetic retinopathy in both eyes was referred to us for treatment in December 2009. Although the patient previously underwent several surgeries, he ultimately lost vision in his right eye. His left eye suffered from neovascular glaucoma after undergoing a pars plana vitrectomy for tractional retinal detachment. After several vitreous and glaucoma surgeries, the patient underwent implantation of a pars plana AGV™. Postoperatively, although his intraocular pressure was stabilized at approximately 10 mmHg, he had repeated vitreous hemorrhage and hyphema without improvement. He ultimately underwent PPV with a silicone oil tamponade and at the same time, the AGV™ tube was pulled out from the vitreous and inserted into the anterior chamber in order to avoid complications caused by the silicone oil.Results: At 19 months postoperative, the patient’s intraocular pressure had stabilized at 10 mmHg with no recurrence of vitreous hemorrhage and hyphema. Eventually, he lost vision in his left eye because of cerebral hemorrhage.Conclusion: The findings show that insertion of a pars plana AGV™ tube into the anterior chamber in a patient undergoing a silicone oil tamponade is both effective and safe in the short-term.Keyword: tube implantation, glaucoma surgery, tube transfer, pars plana, proliferative diabetic retinopathy, intraocular pressure