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PURPOSE: To evaluate the characteristics and formation mechanism of condensation on the posterior surface of various types of intraocular lenses (IOLs) during vitreous surgery. METHODS: A model eye was immersed in a constant-temperature bath, and the temperature and humidity inside the vitreous cavity were maintained at 35˚C and 97%, respectively, to cause condensation (moisture formation) on the IOL. The condensation was video recorded under a microscope, and the size of the condensation droplets and the number per unit area (500 μm2) were determined. The contact angle of the water droplets on each IOL was evaluated by using the sessile-drop method. RESULTS: The condensation droplet diameter for the polymethyl methacrylate (PMMA), acrylic, and silicone IOLs was 115 ± 32 μm, 74 ± 23 μm, and 50 ± 13 μm, respectively. The number of droplets per unit area was 18.4 ± 1.8, 48.2 ± 16.8, and 86.8 ± 6.7, respectively. Statistical analysis showed significantly smaller sizes but a greater number of droplets per unit area for the silicone IOL. The contact angle for the PMMA, acrylic, and silicone IOLs was 76.4˚, 85.7˚, and 112.8˚, respectively. Thus, for silicone, the contact angle was lowest and the water droplets were spherical. CONCLUSIONS: Condensation occurs regardless of the IOL material. Compared to other IOLs, the silicone IOL had smaller-sized but a larger number of spherical condensation droplets. This can cause a large amount of refraction of intraocular light, thus leading to decreased visibility.

Retention durability, especially in the eye, is one of the most important properties of ophthalmic viscosurgical devices (OVDs) during ocular surgery. However, the information on the physical properties of OVDs is insufficient to explain their retention durability. The purpose of this study is to clarify the mechanism of OVD retention to improve understanding of the behavior of OVDs during ocular surgery. To elucidate the mechanism of OVD retention, we have developed a new test method for measuring repulsive force. As a result, the maximum repulsive force of OVDs was positively and well correlated with the retention durability of investigated OVDs. Consequently, we demonstrated that the repulsive force could be used as an index of retention durability on the ocular surface and in the eye. We directly compared the intraocular retention durability of three OVDs (Shellgan, Viscoat, and Opegan-Hi) in ex vivo porcine eyes. Opegan-Hi was immediately removed from the anterior chamber, but Shellgan and Viscoat remained largely in the anterior chamber as determined by fluorescence imaging. These results showed that the intraocular retention behavior of OVDs was similar to their ocular surface behavior in our previous report, suggesting that retention durability is dependent on the OVD itself. The retention durability of Shellgan seemed to be higher than that of Viscoat, and the maximum repulsive force of Shellgan was 1.35-fold higher than that of Viscoat. Therefore, the repulsive force might be a useful index for assessing the difference in the retention durability between OVDs such as Shellgan and Viscoat.

Ophthalmic viscosurgical devices (OVDs) are mainly divided into two general categories: cohesive and dispersive. Dispersive OVDs such as the 3% hyaluronic acid and 4% chondroitin sulfate (HA/CS) combination have excellent adhesion to ocular tissues and protect the corneal endothelium to a greater extent than cohesive OVDs. Herein, we summarize our recent findings regarding one of the properties of the HA/CS combination related to clinical performance. (i) The room temperature stability of OVDs and needle clogging by OVDs remain clinical issues. We demonstrated that adding d-sorbitol to the HA/CS combination preserved its viscosity, which was equivalent after 2 year-storage at room temperature to the viscosity of HA/CS combination stored under refrigeration for 2 years without d-sorbitol. Besides, the HA/CS combination with d-sorbitol could be used repeatedly without cleaning or replacing the needle, suggesting that the addition of d-sorbitol prevents drying and solidification of the OVD on the needle. (ii) Although it can be inferred from numerous studies that the tissue adhesion of OVDs influences their retention by the eye, little is known about the physical properties of OVDs that contribute to intraocular retention. To address this issue, we compared two types of adhesive forces, detachment force and repulsive force, for each OVD. Compared with other dispersive OVDs, the HA/CS combination showed higher values for both adhesive forces. These results suggest that adhesive forces may be used as an index of dispersive OVD retention in the eye.

Purpose To evaluate the effects of D-sorbitol addition on changes in the extrusion force of ophthalmic viscosurgical devices (OVDs). Methods OVD formulations; the mixtures of 3% hyaluronic acid (HA) and 4% chondroitin sulfate (CS) containing 0%, 0.5%, or 1.0% D-sorbitol were prepared. Each prefilled syringe of OVD was stored at room temperature for 0, 15, 30, 60, or 120 mins after a small amount of viscoelastic agent was discharged from the needle. The extrusion force values (kgf) of these OVDs when reused after storage were measured with a texture analyzer. Moreover, 10 healthy adults (5 men and 5 women) used a pinch sensor to measure the extrusion force values for the HA/CS combination without D-sorbitol which was stored in the above manner, and used a 4-step scale to score the usability of OVD. Results For the HA/CS combination without D-sorbitol, the extrusion force value was increased from its initial value (storage duration, 0 min) as storage duration increased. However, for the HA/CS combination containing 0.5% or 1.0% D-sorbitol, this value remained almost unchanged over time. Likewise, the pinch sensor-determined extrusion force values of HA/CS combination without D-sorbitol increased, depending on storage duration. Conclusion The addition of D-sorbitol to viscoelastic agent may suppress the needle clogging that occurs with OVD storage, and may improve the usability of OVDs during surgery.

Purpose To compare the effect of decentration and tilt on the optical performance of 6 aspheric intraocular lens (IOL) designs in a model eye. Setting Department of Ophthalmology, Graduate School of Medicine, Dokkyo Medical University, Tochigi, Japan. Design Experimental study. Methods In theoretical simulations, the amount of spherical aberration in the IOL was varied to produce residual ocular spherical aberration (range −0.15 to 0.30 μm) at a 6.0 mm entrance pupil. Wavefront aberration analyses were performed with the ZEMAX optical design program (version August 20, 2014) to obtain the ocular root-mean-square values of astigmatism, coma, trefoil, and higher-order aberrations (HOAs) when the IOL was centered on the insertion position and misaligned at a 4.0 mm entrance pupil. The retinal visual images were calculated using the same conditions. Six 20.0 diopter (D) aspheric IOLs and one 20.0 D spherical IOL were used for the experimental studies. Each IOL was inserted in the model eye. The actual alignments were measured using a Scheimpflug camera (EAS-1000). The wavefront aberrations and visual images were gauged using a wavefront analyzer (KR-1W) at several IOL alignments. Results Intraocular lens decentration and tilt increased wavefront aberrations and degraded optical performance. Astigmatism, coma, and HOAs generated by misaligned IOLs were related to the amount of spherical aberration correction of the IOLs. The extent of spherical aberration remained unchanged by the amount of misalignment. Experimental model eye results showed trends similar to theoretical results. Conclusions The spherical aberration correction amount in the aspheric IOL design was critical for the astigmatism, coma, and HOAs generated by the IOL misalignment. Additional spherical aberration corrections led to a more sensitive optical performance degradation resulting from IOL misalignment.

To disclose histological advantages of intrascleral fixation of intraocular lens haptics, in comparison with scleral suture fixation, in a study with rabbits. Ten white rabbits, 10 weeks of age, were used in this experimental histopathological study. After unilateral lensectomy and anterior vitrectomy, an intraocular lens haptic was inserted into one eye of each rabbit. Intrascleral fixation was performed in five rabbits, whereas scleral suture fixation was performed in the others. At postoperative 1 week, the globe was enucleated in two rabbits in each group; at postoperative 8 weeks, the globe was enucleated in the remaining three rabbits in each group. Sections of the sclera around haptics and sutures were evaluated with haematoxylin and eosin and immunohistochemical staining methods. We assessed severity of inflammation on histopathological photos, taken near the haptic or suture in the sclera, by counting white blood cells. The Mann-Whitney U test was performed to analyse differences in the severity of inflammation between the groups. Samples in the intrascleral fixation group demonstrated reduced irregularity of collagen fibres; reduced infiltration of fibroblasts, giant cells, lymphocytes, neovascular cells, neutrophils and eosinophils and weaker staining for fibronectin (indicating tissue repair) and heat shock protein 70 (indicating cell damage). In addition, reduced white blood cell infiltration was observed in the intrascleral fixation samples at 8 weeks in both shallow sclera (p = 0.001) and deep sclera (p = 0.002). Histological analysis showed that intrascleral fixation caused fewer inflammatory changes than scleral suture fixation, with reduced fibroblast migration and production of cytotoxic factors.

High-temperature reverse bias (HTRB) and high-humidity HTRB (H3TRB) tests were carried out on 4H-SiC diodes to investigate the mechanism of charge accumulation at the SiO2/SiC interface in the edge termination area, which causes breakdown voltage instability. A differentiated capacitance–reverse voltage method was used to analyze the charge distribution. With HTRB, the charge accumulation occurred in the edge termination area with a passivation of O2 oxidation film and the one with a NO oxidation film. In contrast, no charge accumulation occurred in the edge termination area without SiO2 as a passivation film. With H3TRB, however, the charge accumulation took place not only in the edge of termination area with O2 oxidation but also in the edge termination area without SiO2. The results of two tests revealed that the edge termination area without SiO2 has little tolerance to charge accumulation in a high-humidity and high-temperature atmosphere, although it has tolerance in a high-temperature atmosphere. The difference of tolerance depending on stress condition suggests that there are two mechanisms of charge accumulation, one related to the SiO2/SiC interface and triggered by applying temperature and voltage stress without humidity and the other does not related to the interface and triggered by applying temperature and voltage stress with humidity.

High-temperature reverse bias (HTRB) and high-humidity HTRB (H3TRB) tests were carried out on 4H-SiC diodes to investigate the mechanism of charge accumulation at the SiO2/SiC interface in the edge termination area, which causes breakdown voltage. To analyze the distribution of charge density during these tests, a differentiated capacitance-reverse-voltage method was used. From comparing the results of the HTRB and H3TRB tests, it was clarified that the H3TRB test induces negative charge at the SiO2/SiC interface but induces positive charge at the polyimide/SiC interface. We concluded that the origin of the increase in charge density induced by high-humidity stress is the corrosion of the anode metal, which depends on the surface film of the SiC in the termination area, namely, the SiO2/SiC or polyimide/SiC interface. The induced charge mechanism can become a guideline for designing highly reliable SiC power devices against humidity stress.

Purpose To develop a single-piece open-capsule intraocular lens (IOL) that can be inserted through a small incision and that prevents posterior capsule opacification (PCO) by expanding the capsule and circulating aqueous humor into the capsular bag. Setting Department of Ophthalmology, Dokkyo Medical University, Tochigi, Japan. Design Experimental study. Method Using the same hydrophobic acrylic material as the NY-60 IOL, a prototype open-capsule IOL was constructed. The IOL has a single optic and 2 haptics, with a 2.8 mm high spacer and holes through which aqueous humor circulates into the capsular bag by separating the anterior capsule from the posterior capsule and expanding the capsule. The open-capsule IOL or NY-60 (as a control group) was inserted in rabbit eyes. Posterior capsule opacification development was evaluated by measuring the thickness of the cell layer at the center of the posterior capsule on histopathologic specimens and statistically comparing the thickness between the open-capsule IOL group and control group. Results The open-capsule IOL could be inserted through a 3.2 mm corneal incision using a D cartridge. The mean thickness of the cell layer at the center of the posterior capsule was 4.78 μm ± 2.61 (SD) in the open-capsule IOL group and 101.14 ± 25.19 μm in the control group and was significantly smaller in the open-capsule IOL group. Conclusion The prototype single-piece IOL could be implanted through a small incision and prevented PCO by expanding the lens capsule and circulating aqueous humor into the capsular bag.

Background To report on five patients with decreased visual acuity due to glistening and severe sub-surface nano-glistening (SSNG) formation within their intraocular lenses (IOLs). Design Case reports and analysis of extracted IOLs. Participants and samples We report improved visual acuity when IOLs with severe glistening and SSNG were exchanged for clear IOLs in five patients. Methods Case reports. Main outcome measures The main outcome measure was visual acuity. The secondary outcome measure was light transmission. Explanted IOLs were subjected to investigation. Pre- and postoperative slit lamp images of the anterior eye and microscopic images of the extracted IOLs were taken and compared. Light transmission of the IOL was measured using a double beam type spectrophotometer. An integrated value of the percentage light transmittance in the visible light spectrum was calculated. Results We report on five patients whose visual acuity improved when IOLs were exchanged because of severe glistening and SSNG. All of the affected IOLs were MA60BM (Alcon, Forth Wroth Texas, USA) and the original implantation had occurred over a range of 6–15years prior to the IOL exchange. Light transmission was decreased in all affected lenses compared to a similar control IOL. Conclusions Although only a few reports of cases in which glistening and SSNG have progressed to the level of decreased visual function have been published, the likelihood is that this phenomena will increase as the severity and incidence of these inclusions have been shown to increase with time. Appropriate evaluations of visual function in such patients are needed and consideration should be given to IOL exchange in symptomatic patients.

Conventional floating-field rings, which are used to reduce the peak electric field at the periphery of power devices, cause nonuniform avalanche multiplication when applied to planar junctions formed on 4H-SiC substrates misoriented from (0001) toward $[{ 11}{\overline {2}}0]$ . Accordingly, a novel asymmetrically spaced floating-field ring (AS-FFR) was applied to 4H-SiC 4°-off (0001) p–n diodes and found to be effective against such nonuniform avalanche multiplication; that is, luminescence at breakdown was nearly uniform when the spacing between the edge of the anode and the inner edge of the AS-FFR was 2.0 ${{\mu }}\text{m}$ in the [ $\overline { 1}{\,}\overline {1}20$ ] direction and 1.5 ${{\mu }}\text{m}$ in the $[{11}{\overline {2}}0]$ direction. This result should contribute to exploring the possibility of 4H-SiC power devices with higher avalanche ruggedness.

A commercial-simulator-based numerical-analysis methodology for 4H-SiC power devices formed on misoriented (0001) substrates is proposed and applied for analyzing avalanche breakdown of floating-field-ring-terminated p-n diodes. Due to the inexpedience of a fixed orientation of the (0001) surface in current commercial device simulators, 4H-SiC (0001) surface is etched to form a miscut to separate the known effects of asymmetric nature of impact ionization and asymmetric aluminum concentration contours. 2-D process simulation of etching a 4H-SiC (0001) surface to expose a sloped surface, patterning the sloped surface with a mask, vertically implanting aluminum ions into the masked surface, removing the mask, and forming electrodes and a SiO2 passivation film was carried out. This process simulation revealed asymmetric lateral straggling of implanted aluminum acceptors. The subsequent device simulation, which assumed fixed charge at the SiO2/4H-SiC interface, revealed asymmetric avalanche breakdown voltage in the misoriented direction and the opposite direction. This asymmetric breakdown qualitatively explains the previously reported nonuniform luminescence at breakdown. The proposed methodology is considered to be applicable to other power devices with other termination structures formed on misoriented 4H-SiC (0001) substrates.

4H-SiC (0001) p-n diodes terminated with a floating-field ring were found to emit light at breakdown in the opposite direction to that of substrate misorientation when the diodes were fabricated by aluminum implantation and dry-oxidation passivation. Two-dimensional simulation revealed that such non-uniform breakdown was mainly attributable to the asymmetric lateral straggling of implanted aluminum acceptors, rather than the anisotropic nature of the impact ionization coefficient.

A novel method for analyzing a decrease in breakdown voltage (VBD) in the termination of 4H-SiC power devices after reverse-bias stressing on the basis of change in depletion-layer capacitance is proposed. Test PN diodes terminated with a junction-termination extension (JTE) were fabricated on n-type 4H-SiC and analyzed by I-V and C-V measurements. According to the results of the measurements, VBD after stressing decreases, and the capacitance of the test devices decreases after stressing. Measurements with different chip sizes but the same termination width show that the capacitance decrease occurs in the termination area. The simulated capacitance change, on the supposition that positive charge accumulated at the SiO2/SiC interface, and the measured capacitance change show the same tendency. These results indicate that the origin of VBD decrease is positive charge accumulated at the SiO2/SiC interface of the termination after reverse-bias stressing.

Passivation films on the termination area of 4H-SiC diodes were investigated to clarify the origin of a positive charge accumulation that induces instability of the breakdown voltage. A method to differentiate measured depletion layer capacitance is proposed as a way to analyze the positive charge density after applying voltage stress. Samples with different passivation films were fabricated to compare the effects of the passivation films. The results of analyzing three kinds of passivation film show that the charge density did not increase in the sample without SiO 2 on the termination area. In addition, the breakdown voltage of the sample did not change after applying stress. The results suggest that the passivation film sample without SiO 2 is effective for suppressing the accumulation of positive charge density.

Purpose To evaluate whether and how intraocular lens (IOL) implantation influences the development of anterior capsule contraction and posterior capsule opacification (PCO). Setting Department of Ophthalmology, Dokkyo Medical University, Mibu, Tochigi, Japan. Design Experimental study. Methods Phacoemulsification was performed in 8-week-old white rabbits. A hydrophobic acrylate IOL (12.5 mm) (YA-60BBR) was implanted in 1 eye and no IOL was implanted in the fellow eye. Slitlamp microscopy and anterior segment analysis were performed to evaluate anterior capsule contraction after the surgery. Four weeks postoperatively, sections of the eyes were made, and the thickness of the proliferated lens epithelial cell (LEC) layer at the posterior capsule was measured to assess the PCO. In addition, LECs from white rabbits were cultured in medium containing 50% aqueous humor or in medium containing 50% saline to determine the influence of the aqueous humor on LECs and to compare the degree of LEC proliferation. Results Starting 2 weeks after surgery, anterior capsule contraction progressed more significantly in the IOL group than in the group without IOLs. Four weeks postoperatively, LEC thickness at the posterior capsule was significantly less in the group without IOLs than in the IOL group. In the culture study, LEC proliferation was more inhibited in the aqueous humor group than in the saline group. Conclusions Progression of anterior capsule contraction and PCO is less likely in aphakic eyes than in IOL-implanted eyes. The mechanism of prevention may involve aqueous humor–induced inhibition of LEC proliferation. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.

Aims: To report the incidence of infectious and noninfectious endophthalmitis after intravitreal injection of anti-vascular endothelial growth factor (VEGF) from a multicenter clinical trial in Japan. Methods: A retrospective multicenter review of the data of patients who received intravitreal anti-VEGF injections between January 2007 and March 2011 was undertaken. Cases with the clinical diagnosis of endophthalmitis resulting from intravitreal injection were identified and reviewed. Results: A total of 5,236 intravitreal anti-VEGF injections (1,209 intravitreal injections of bevacizumab, 3,827 injections of ranibizumab, and 200 injections of pegaptanib sodium) had been administered. Five patients (0.095%), all of whom had received bevacizumab, were diagnosed as having endophthalmitis after the intravitreal injection. All patients visited the institutes for re-examination within 1–2 days after the injection. Among the 5 patients, 2 (0.038%) were culture positive for Streptococcus oralis and Enterococcus faecalis, respectively. The remaining 3 eyes (0.057%) developed presumed noninfectious endophthalmitis. Conclusion: Although endophthalmitis is a rare complication associated with intravitreal injection, in this series intravitreal anti-VEGF injection caused infectious or noninfectious endophthalmitis at a relatively high frequency. Further investigations are needed to consider an appropriate injection protocol for minimizing the incidence rates of endophthalmitis, and to assess the optimal treatment protocol for intravitreal injection-related endophthalmitis although it was difficult to differentiate these two entities.

Advances in intraocular lens (IOL) design have led to the use of lenses with improved performance including tinting, asphericity, multifocality and accommodation. To maximize the visual performance of these IOLs, postoperative complications such as secondary cataracts and anterior capsule contraction must be prevented. Various types of secondary cataracts may occur, each associated with complex biological reactions. Different design configurations, including square-edge IOLs, have been used to prevent secondary cataracts and anterior capsule contraction, but these have not been successful in sufficiently eliminating these complications. We have found that surface modification of IOL surfaces chemically improves surface quality and is also useful in preventing secondary cataracts and anterior capsule contraction. The UV/ozone treatment that we used as a surface modification method is a simple and highly effective method with no safety issues regarding materials following treatment. The combination of square-edge design and surface modification may be able to completely eliminate these postoperative complications.

Purpose To evaluate active oxygen processing on the surface of acrylic intraocular lenses (IOLs) to prevent secondary posterior capsule opacification (PCO). Setting Department of Ophthalmology, Dokkyo Medical University School of Medicine, Mibu City, Tochigi, Japan. Methods Acrylic IOLs were prepared, and ultraviolet (UV)/ozone (UV/O 3 ) or argon plasma was irradiated to the surface of the IOLs. Elemental analysis (electron spectroscopy for chemical analysis [ESCA]) of the IOL surfaces was performed to confirm surface modification. Changes produced by UV/O 3 or argon plasma treatment were examined for fibronectin and lens epithelial cell (LEC) adhesion. To evaluate the PCO prevention by treated IOLs, 8-week-old albino rabbits were used. The rabbit eyes randomly had phacoemulcification and implantation of 3 different IOLs: the UV/O 3 -treated IOLs, argon plasma–treated IOLs, and the control IOLs. After 2 weeks, the rabbits were killed and their globes were dissected and fixed using formaldehyde 10%. The PCO was observed using light microscopy (DX51, ORIMPUS) after hematoxylin and eosin staining. Results Comparison of IOL surface composition by ESCA showed an increase in nitrogen content and hydroxyl substitute and carboxyl substitute groups on surfaces of treated IOLs. The fibronectin adhesion and the LEC adhesion on the UV/O 3 -treated and argon plasma–treated samples were increased. In the untreated group, there was statistically significant inhibition of PCO formation in the UV/O 3 -treated and argon plasma–treated groups. Conclusion Active oxygen processing and argon plasma irradiation on the surface of IOLs was effective in preventing secondary PCO after cataract surgery.

The aim of this study was to determine the frequency of heparin/platelet factor (PF) 4 complex antibodies in 305 uremic patients treated with chronic intermittent hemodialysis using unfractionated heparin or low-molecular-weight heparin for 3 months. Heparin-induced thrombocytopenia (HIT) antibodies were detected by ELISA in 7 patients (2.3%) who had no history of HIT. Two patients abruptly developed HIT associated with the formation of clots in the extracorporeal circuit after they were found to be carrying HIT antibodies. These patients were suspected to have a similar trigger: an increased dose of recombinant human erythropoietin (rHuEPO). The drug might induce parallel changes in hematocrit (Ht) levels and platelet counts until the onset of HIT. After the onset of HIT, a parallel phenomenon between Ht and platelet counts was not found because of the thrombocytopenia due to HIT. Although HIT onset has been reported during the initial phase of dialysis sessions, there have been few reports on the onset of HIT in uremic patients on dialysis with long-term heparin anticoagulation. In this study, HIT was observed in 2 uremic patients on chronic dialysis with intermittent use of heparin. In some patients on chronic intermittent dialysis carrying HIT antibodies, HIT may occur following rHuEPO treatment. The presence of HIT should be borne in mind in chronic dialysis patients carrying HIT antibodies for 3 months or more.

* BACKGROUND AND OBJECTIVE: Secondary posterior subcapsular opacification is still among the most important complications after phacoemulsification. * MATERIALS AND METHODS: This study was designed to assess the inhibitory effects of drugs delivered via hydrophilic acrylic (hydrogel) intraocular lens (IOL) systems in vitro. Lens epithelial cells were collected from albino rabbits. The following seven groups of hydrogel IOLs were prepared: untreated IOLs and IOLs infiltrated with diclofenac sodium, tranilast, mitomycin C, colchicines, 5-fluorouracil, and ethylenediaminetetraacetic acid. The IOLs were fixed to a Cell Culture Insert; they were then bathed and incubated in minimum essential medium containing cultured lens epithelial cells. Subsequently, a comparative analysis of the cells adhering to the collagen membrane and the lens surfaces was conducted. * RESULTS: Adhesion of lens epithelial cells to the lens surfaces and the collagen membrane was observed in the control group. However, only slight cellular adhesion was found on the surfaces of the IOLs and on the collagen membrane in the treated IOL groups. * CONCLUSION: Use of hydrogel IOLs infiltrated with drugs was associated with inhibition of posterior subcapsular opacification in vitro. [Ophthalmic Surg Lasers Imaging 2005;36:386-392.]

To analyze the effect of calcium on human lens epithelial cells (LECs) in vitroHuman LECs were obtained from the anterior lens capsule during a cataract operation, and were cultured in minimum essential medium (MEM) containing 12% fetal bovine serum for a week at 37 degrees C, 5% CO(2). The LECs were then isolated with trypsin and placed in culture dishes. To analyze the effects of calcium, the LECs were incubated in MEM with calcium concentrations of 0, 2, 10, or 20 mM. After HE staining for 72 h, the LECs were analyzed with the Scion imaging program.The LECs proliferated rapidly and their shapes were uniform in 2-mM-calcium MEM. The LECs proliferated more slowly and had irregular shapes in MEM with lower and higher concentrations of calcium.Calcium affects both the proliferation and the shape of human LECs in culture. Abnormal (hyper- or hypo-) calcium concentrations in the lens and aqueous humor may change the homeostasis of LECs, resulting in cataracts and secondary posterior capsular opacification.

Purpose: To analyze selected lens cytoskeletal proteins in posterior capsule opacification (PCO) 2 weeks after intraocular lens (IOL) implantation in rabbits. Setting: Department of Ophthalmology, Dokkyo University School of Medicine, Tochigi, Japan. Method: Eight 10-week-old albino rabbits were prepared and anesthetized for phacoemulsification and aspiration of the crystalline lens and implantation of an acrylic or a hydrogel IOL. Two weeks postoperatively, the rabbits were killed and the IOLs removed for immunohistochemistry. Deparaffinized tissue sections were processed with antibodies against α-smooth muscle actin (α-SMA) and β-crystallin to observe the types of PCO with the 2 IOL types. The proteins in the PCO tissue and the normal lens were homogenized, centrifuged, and analyzed using SDS-polyacrylamide gel electrophoresis (SDS-PAGE) densitometric analysis and Western immunoblotting for actin and vimentin. Results: Immunohistochemistry demonstrated a fibroblastic cell type expressing α-SMA and partial regeneration of epithelial cells, resulting in a lenticular structure that stained irregularly for β-crystallin. The immunoreactivity of fibroblast-like cells to β-crystallin appeared weaker than that of the regenerated lenticular structure. SDS-PAGE showed variability in the content of cytoskeletal proteins in the insoluble fractions of the PCO. Degradation of the cytoskeletal components was greater with the acrylic IOL than with the hydrogel IOL. Conclusion: Cytoskeletal proteins expressed during the formation of PCO and IOL implantation may have potential as therapeutic target proteins to improve the biocompatibility of IOLs.

Up-regulation of glomerular extracellular matrix and transforming growth factor-βbgr; expression in RF/J mice. Background RF/J mice were first reported as a murine model of spontaneous glomerulosclerosis by Gude and Lupton in 1960, but the precise histologic characteristics and immunopathological background of this mouse have not been investigated further. Methods Measurements of serum levels of immunoglobulins, anti-single strand DNA (anti-ss-DNA) antibody, complement (C 3 ), and circulating immune complex (IC) were performed. Analyses of glomerular histological and immunopathological lesions in association with the detection of mRNA expression of collagen IV, TGF-βbgr;, matrix protein turnover related enzymes, matrix metalloproteinase-2 (MMP-2), tissue inhibitor of metalloproteinase-2 (TIMP-2) and platelet-derived growth factor (PDGF) were also performed in young (10-week-old) and elderly (60-week-old) RF/J mice with age-matched BALB/C mice as the controls. Results High levels of serum IgA and IgG from as early as 20 weeks of age were noted in the RF/J mice. Serum anti-ss-DNA antibody of aged RF/J mice increased up to 23% of that of aged MRL- lpr/lpr mice, and serum C 3 concentration significantly decreased with age, reaching lower levels than that of BALB/c mice. IgA-IC levels were significantly high compared to BALB/C mice both in the early and late stages of life, whereas IgG-IC levels were high only in mice younger than 20 weeks. Semiquantitative and quantitative analyzes of renal histopathological findings revealed significantly marked and age-related mesangial matrix expansion in RF/J mice, with increasing frequency of global glomerular sclerosis and tubulointerstitial damage. On the other hand, although precise measurements of glomerular cell numbers also showed an apparent augmentation in both young and old RF/J mice compared to BALB/C mice, glomerular cellularity decreased with age in RF/J mice. Immunohistochemical study revealed massive immunoglobulin deposition from a young age in association with significantly higher accumulation of matrix proteins, such as types I and IV collagen and laminin from the early stage of life. In addition, in these glomeruli, transforming growth factor-βbgr;1 (TGF-βbgr;1) was highly expressed both in young and old mice. The mRNA expression of MMP-2 was up-regulated only in the early stage of life. Although PDGF mRNA of RF/J mice was significantly up-regulated in the early stage of life, the differences between the mice disappeared in the late stage of life. Conclusions These findings suggest that in RF/J mice, an immunopathological background inducing high serum immunoglobulin and IC levels from the early stage of life is closely related to mesangioproliferative glomerular lesions mediated by PDGF, and that development of massive extracellular matrix accumulation in glomeruli was induced by up-regulated expression of TGF-βbgr; with inappropriate regulation of protein turnover-related enzyme production.

This study of lens protein composition found that some cytoskeletal proteins were degraded during the earliest stages of cataract formation. Cataract was induced in 13–14 day old rats by a single subcutaneous injection of sodium selenite (19 μmol kg −1 ). By 24 hr after the injection of selenite, the ratio of insoluble to soluble protein increased as lens opacification began. The increase in insoluble protein aggregates was correlated with an accelerated loss of proteins having molecular weights of 42, 55/57 and 235 kDa which reacted with antibodies to the cytoskeletal proteins actin, tubulin/vimentin and spectrin, respectively. We observed the loss of 49, 60 and 90 kDa proteins which were not identified. In the lenses of animals protected from protein aggregation and opacification by administration of 1.5 mmol kg −1 pantethine, the pattern of proteins in SDS-PAGE gels resembled the pattern for proteins from transparent lenses of normal untreated animals and loss of cytoskeletal proteins was prevented.

An outbred mouse strain known as ddY has been reported to spontaneously develop, late in life, mesangioproliferative glomerulonephritis with a severe glomerular immunoglobulin A (IgA) deposition that mimics human IgA nephropathy. However, the incidence of the disease in this strain is not very high, probably due to its heterogeneous genetic background. Therefore, we attempted to isolate a strain with a high incidence and an early onset of the disease through selection for high serum IgA from the outbred ddY mice. The selection procedure was successful in increasing the serum IgA level of the selected line and proved effective both in increasing the incidence and in accelerating the onset of the disease. We propose to designate this line of mice 'HIGA', denoting a line with high serum IgA levels. More than half of the mice from the HIGA strain showed a moderate to severe glomerular IgA deposition as early as 25 weeks of age. The severe deposition observed was comparable to that occasionally seen in the original nonselected ddY strain after 40 weeks of age. Thus, we have succeeded in generating a mouse model of IgA nephropathy with a high incidence and an early onset of glomerular IgA deposition. Using light microscopy, progressive and marked mesangial matrix accumulation was shown to develop in HIGA mice. However, they showed only mild proteinuria (100-300 mg/dl) and did not show hematuria.

disorder resulting from clonal expansion of a transwith stage III hypertension and stage II arteriolosclerformed haematopoietic stem cell associated with prominent overproduction of erythrocytes, and to a lesser otic retinopathy by Scheie’s classification. Cardiac ausextent expansion of granulocytic and megakaryocytic cultation revealed accentuated second and fourth heart elements. Previous reports presented three cases of sounds. There was neither splenomegaly nor abdompolycythaemia vera associated with diffuse mesangiop- inal bruit. Both lower extremities had pruritus and the

Summary: The relationship between the patency status of the autogenous arteriovenous (A-V) fistula and the plasma level of endothelin-1 (ET-1) was studied in 41 patients who had been receiving routine longterm haemodialysis for more than 10 years. the ET-1 level in the haemodialysis patients (mean ± s.d.=2.1 ± 0.9 pg/mL) was significantly elevated compared with that in healthy controls (n=16; 1.1 ± 0.4 pg/mL; P < 0.01). the patients were classified into two groups according to whether the original A-V fistula had remained patent for more than 10 years or had been repaired due to frequent (more than twice) obstruction. Among all 41 patients, 21 were receiving recombinant human erythropoietin (rHuEpo) intravenously (i.v.). In the rHuEpo-treated group, the plasma ET-1 (n=21; 2.4 ± 0.8 pg/mL) was significantly elevated than that in the rHuEpo-untreated group (n=20; 1.9 ± 0.9 pg/mL; P

Atherosclerotic changes have not been demonstrated directly in asymptomatic hyperglycaemic non-diabetic subjects, although high mortality due to coronary heart disease has been reported. We measured arterial wall thickness non-invasively, in order to directly demonstrate atherosclerosis of the carotid arteries of hyperglycaemic non-diabetic subjects and to evaluate its risk factors. The thicknesses of the intimal plus medial complex (IMT) of the carotid arteries of 112 asymptomatic hyperglycaemic non-diabetic subjects (aged 22-81, 95 males and 17 females) were compared with those of 55 healthy male subjects and 211 non-insulin-dependent NIDDM male diabetic patients. The subjects were subgrouped into impaired glucose-tolerant (IGT) subjects who had a 2-h glycaemic level of more than 7.8 mmol/l, and non-IGT subjects whose 2-h glycaemic levels were within 6.7-7.7 mmol/l. Non-IGT and IGT subjects showed significantly greater IMTs than age-matched healthy males and showed no significant differences compared to age-matched NIDDM patients. Multivariate analysis demonstrated that the risk factors for IMT of non-IGT and IGT subjects were age and systolic blood pressure. According to data on the accumulation of atherogenic risks (hypertension, dyslipidaemia, and smoking), IMT increased linearly in non-IGT and IGT subjects. However, non-IGT and IGT subjects without hyperlipidaemia, hypertension, or smoking risk still had significantly greater IMT than age-matched normal males (1.019 +/- 0.063 vs 0.770 +/- 0.111 mm, p0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

A decrease in breakdown voltage (VBD) in the termination area of 4H-SiC PN diodes after 64 h reverse-bias stressing was analyzed. To analyze the VBD decrease, a novel analysis method based on the results of measuring depletion-layer capacitance of the PN diodes was proposed. The measurement results indicate that the positive-charge density (QTM) at the SiO2/SiC interface of the termination area increased after the reverse-bias stressing. Besides, in the case of QTM of 1012 cm−2 at the SiO2/SiC interface, the decrease in the measured capacitance showed the same tendency as the decrease in the simulated capacitance. By comparing the measured full depletion voltage and simulated full depletion voltage, the amount of QTM was estimated. It is thus concluded that the proposed method for measuring the depletion-layer capacitance is effective for analyzing the QTM change in the termination area.

The distribution of positive-charge density at the SiO2/SiC interface of the termination area (Q TM) was analyzed by measuring the depletion-layer capacitance of 4H-SiC PN diodes with different termination structures. A change in Q TM induced by reverse-bias stressing (ΔQ TM) caused a change in the breakdown voltage of the diodes. By comparing the measured depletion-layer capacitance to the simulated value, the initial Q TM ( ) and the distribution of ΔQ TM were clarified. It is concluded from these results that the distribution of ΔQ TM was not uniform but that positive charges mostly accumulated in the termination area under a high applied electric field.

We studied 27 non-insulin-dependent diabetics without apparent atherosclerosis (AS) to investigate whether abnormal platelet function is related to asymptomatic atherosclerosis in diabetes mellitus. The degree of AS was quantitatively evaluated by determining the intimal plus medial thickness (IMT) of the carotid artery wall with ultrasound high-resolution B-mode imaging. Based on our previous finding that the upper threshold of the IMT was 1.1 mm in healthy subjects, the patients were divided into the AS-positive group with the IMT1.1 mm, (n = 17) and the AS-negative group with the IMT1.1 mm (n = 10). Among five variables measured as the factors concerned with thrombogenesis, only plasma levels of beta-thromboglobulin (beta-TG) and platelet factor 4 (PF4) were significantly higher in the AS-positive group than in the AS-negative group. Chronic administration of pentoxifylline (300 mg/day) significantly reduced the abnormally high plasma levels of beta-TG and PF4 in 7 patients of the AS-positive group to normal levels, without lowering the normal plasma beta-TG and PF4 levels in the remaining 10 patients. Pentoxifylline treatment did not affect the plasma levels of the 3 other variables, von Willebrand factor, 6-keto prostaglandin F1 alpha and thromboxane B2. This study suggests that the progress of atherosclerosis in diabetes mellitus is associated with in vivo platelet activation and platelet activation does not occur in diabetics without carotid atherosclerosis. Pentoxifylline may impede the vicious cycle in which atherosclerosis is accelerated by platelet activation.

This paper describes a robust transmission method for KHz-band PLC. The method is robust for heavy interference from electric appliances. Interference is not always stochastic in nature, as it is an artificial event. Thus, any transmission method based on Shannon's theory will not always yield reliable results. The robust transmission method proposed in this paper is to detect the correct symbol when the interference generated by many electric appliances fades out. However, interference-free zones cannot be determined within drastically time-variant interference envelopes, and they cannot be detected directly from the shape of the received signal. Interference-free zones can only be identified if an adaptive receiver outputs the true symbol. In order to solve this dilemma, we introduce a blind equalizer with rapid convergence. In addition, we employ a code that has symbol-position information built into the symbol sequence of the data frame. Through the combination of these two methods, we can maintain connections even when fading-out intervals are very short, by exploiting speed-reductions in the information rate. Implementing this method on a FPGA, we demonstrate that robustness can be realized even under the most problematic case of real KHz-band PLC networks. Application of this technique is vital for building dependable systems to control for electric appliances.

Purpose To clinically evaluate postoperative changes in the transparency of hydrophobic acrylic intraocular lenses (IOLs). Setting Department of Ophthalmology, Dokkyo Medical University, Tochigi, Japan. Design Case-control study. Methods Eyes having phacoemulsification were randomly assigned to have implantation of 1 of 3 hydrophobic acrylic IOL models. The IOLs were photographed at 0 degree and 90 degrees 1 week, 6 months, and 1 year after implantation using a Nidek EAS-1000 anterior chamber analyzer in slit mode. The images were used to determine the intensity of light scattering in the surface and middle regions of the IOL optic. Results The study comprised 65 eyes of 57 patients with a mean age of 72.5 years. The rate of increase in light-scattering intensity was similar in the middle and surface regions of the Tecnis ZA9003 aspheric IOL. The increase in light-scattering intensity in both regions of the AF-1 VA-60BB spherical IOL was greater than that in the aspheric IOL at all the measurement points. The intensity of light scattering was highest and tended to increase over time in both regions of the AcrySof SA60AT spherical IOL; the rate of increase in intensity was higher in the surface region than in the middle region, and the difference was significantly greater at 6 months and 1 year than at 1 week. Conclusion Our results suggest that AcrySof SA60AT and AF-1 VA-60BB IOLs are likely to develop glistenings over time and that the former may develop whitening. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.

To investigate the effects of light scattering from the surface of hydrophobic acrylic intraocular lenses (IOLs) on visual function.A 67-year-old man was implanted with an IOL (MA60BM) in January 1998, but became aware of decreased visual function in May 2008. Observation with a slit lamp revealed light scattering throughout the entire optic of the IOL, which was extracted and replaced. Postoperative visual function improved at 1 month. The cause of light scattering was investigated with a focus on water permeating the IOL material. To confirm the effect of light scattering on visual function, light transmission of the extracted IOL was measured in physiological saline at 33 °C, and the simulated retinal image was evaluated in a model eye.Observation of the extracted IOL showed light scattering from the optic surface layer, the main cause of which was phase-separated water within the IOL material. Light transmission in the extracted IOL was 16.3% lower than that in an unused IOL in the visible range. Moreover, the simulated retinal image was hazy compared to that of the unused IOL.Severe surface light scattering from an IOL optic may decrease visual function.

OBJECTIVE To quantitatively assess atherosclerosis of the carotid artery in subjects with and without diabetes. RESEARCH DESIGN AND METHODS Ultrasound high resolution B-mode imaging of carotid arteries was conducted on 71 nondiabetic subjects without hyperlipidemia or hypertension and 295 diabetic patients to determine IMT of the arterial wall. RESULTS IMT was linearly related with age in nondiabetic (IMT = [0.0087 × age] + 0.3318) and diabetic subjects (IMT = [0.0155 × age] + 0.32450). The regression coefficient for age was significantly greater in diabetic than nondiabetic subjects. IMT (mean ± SD) of diabetic subjects aged 20–29 was significantly > that of nondiabetic subjects aged 20–29 (0.73 ± 0.27 vs. 0.52 ± 0.07 mm, P < 0.01). Multivariate regression analysis of 275 NIDDM patients indicated smoking, hyperlipidemia, duration of diabetes, hypertension, and age were factors determining thickness of the carotid arterial wall. CONCLUSIONS Diabetes, along with age, hyperlipidemia, smoking, and hypertension, aggravates carotid atherosclerosis.

Purpose To identify the cause of light scattering on the surface (ie, whitening) of extracted AcrySof intraocular lenses (IOLs). Setting Department of Ophthalmology, Dokkyo Medical University, Tochigi, Japan. Methods Dislocated IOLs extracted from 3 patients were stored and the IOL surfaces examined under light microscopy. The effect of whitening on visual function was evaluated by measuring light transmission with a spectrophotometer. To determine the cause of opacification, the IOLs were examined for calcium phosphate deposits using an electron probe X-ray microanalyzer. The IOL surface, including the presence of organic deposits and evidence of hydrolysis, was also examined by Fourier-transform infrared spectrophotometry. The IOLs were then dried, immersed again in physiological saline, and serially examined for changes in opacification. Results The optic surfaces of all IOLs had opacification due to whitening. Light transmission in the visible range of 360 to 800 nm was 4% less than that of unused IOLs. The X-ray microanalysis showed no calcium phosphate deposits. Fourier-transform infrared spectrophotometry of the IOL optic material showed no evidence of hydrolysis. Opacification disappeared after the IOLs were dried and then reappeared over time when the IOL was immersed again in physiologic saline. Conclusions The findings strongly suggest that whitening of the hydrophobic acrylic IOL was due to trace water molecules that infiltrate the optic. Within the 3-dimensional network of the polymeric lens material, the molecules are too small to form observable voids but can form water aggregates of sufficient size to scatter visible light, causing opacification (ie, whitening).