H Abe

Niigata University, Niahi-niigata, Niigata, Japan

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Publications (141)214.2 Total impact

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    ABSTRACT: The caveolin 1 to caveolin 2 (CAV1-CAV2) gene region on chromosome 7q31 has been reported to be associated with susceptibility to primary open angle glaucoma (POAG) and normal tension glaucoma (NTG) in previous studies. We investigated whether genetic variants in the CAV1-CAV2 region are associated with NTG in Japanese patients. Two hundred and ninety-two Japanese patients with NTG and 352 Japanese healthy controls were recruited. We genotyped three single-nucleotide polymorphisms; that is, rs1052990, rs4236601, and rs7795356, in the CAV1-CAV2 gene region and assessed the allelic diversity among cases and controls. The frequency of the minor allele (G) of rs1052990 was significantly decreased in NTG cases compared with controls (P=0.014, OR=0.71), whereas NTG or POAG cases had a significantly higher frequency of the allele than controls in previous studies. Conversely, rs7795356 did not show any significant association with NTG cases, and rs4236601 was monomorphic in the Japanese study population. Our findings did not correspond with previous positive results, suggesting that CAV1-CAV2 variants studied in the present study are not important risk factors for NTG susceptibility in all populations. Further studies are needed to elucidate the possible contribution of the CAV1-CAV2 region to the development of glaucoma.Eye advance online publication, 7 June 2013; doi:10.1038/eye.2013.123.
    Eye (London, England) 06/2013; · 1.97 Impact Factor
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    ABSTRACT: To investigate whether the GLC3A locus harboring the CYP1B1 gene is associated with normal tension glaucoma (NTG) in Japanese patients. One hundred forty-two Japanese patients with NTG and 101 Japanese healthy controls were recruited. Patients exhibiting a comparatively early onset were selected as this suggests that genetic factors may show stronger involvement. Genotyping and assessment of allelic diversity was performed on 13 highly polymorphic microsatellite markers in and around the GLC3A locus. There were decreased frequencies of the 444 allele of D2S0416i and the 258 allele of D2S0425i in cases compared to controls (P = 0.022 and P = 0.034, respectively). However, this statistical significance disappeared when corrected (Pc > 0.05). We did not find any significant association between the remaining 11 microsatellite markers, including D2S177, which may be associated with CYP1B1, and NTG (P > 0.05). Our study showed no association between the GLCA3 locus and NTG, suggesting that the CYP1B1 gene, which is reportedly involved in a range of glaucoma phenotypes, may not be an associated factor in the pathogenesis of NTG.
    Clinical ophthalmology (Auckland, N.Z.) 02/2009; 3:183-8.
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    ABSTRACT: This study sought to elucidate the effects of timolol and dorzolamide on intraocular pressure (IOP) and retinal ganglion cell (RGC) death in an experimental model of glaucoma in rat. Mild elevation of IOP was induced in rats by intracameral injection of India ink and subsequent laser trabecular photocoagulation. IOP was measured before the surgical procedures and weekly thereafter. Timolol (0.5%), timolol XE (0.5%), dorzolamide (1%), and artificial tears (vehicle) were topically applied daily. Retinal sections were prepared for histology to determine RGC number. Timolol, timolol XE, and dorzolamide induced a significant reduction in IOP (p<0.05) and counteracted the reduction in RGC number that occurred in vehicle treated glaucomatous eyes (p<0.05). The coefficient of correlation between RGC number and IOP was significant in the dorzolamide treated group (r = -0.908, p<0.005), but not in other groups (p>0.05). Both timolol formulation and dorzolamide reduced IOP and protected RGCs in a rat model of experimental glaucoma. It cannot be ruled out that timolol might protect RGCs by additional mechanisms other than simply lowering of IOP.
    British Journal of Ophthalmology 04/2005; 89(4):504-7. · 2.73 Impact Factor
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    British Journal of Ophthalmology 04/2003; 87(3):371-2. · 2.73 Impact Factor
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    ABSTRACT:  Hemoglobin (Hb) vesicles are artificial oxygen carriers that encapsulate concentrated purified Hb with a phospholipid bilayer membrane. They have been confirmed to have sufficient oxygen-transporting ability. Even though strictly inspected outdated red cells are used as a source of Hb, it is necessary to introduce an additional process that inactivates or removes viruses in the process of Hb purification in order to guarantee the utmost safety from infection. In this study, Hb filtration to remove viruses was tested with Planova 35N and 15N (virus removal fitters with a Bemberg microporous membrane). The permeation flux (LMH) and the permeated ratio of Hb solution ([Hb] = 5.6 g/dl) through Planova 35N at 13°C were 36 l/m2/h and almost 100%, respectively. The values for Planova 15N at 13°C were 15 l/m2/h and 95%, respectively. The permeation flux increased to 18 l/m2/h when the temperature was raised to 25°C. Under the same conditions, a high efficiency of removal of a bacteriophage, φX174, was confirmed (>7.7 log). These results indicate that Planova 15N is effective for the process of virus removal from Hb solution.
    Journal of Artificial Organs 01/2002; 5(2):141-145. · 1.41 Impact Factor
  • H Abe, S Shuto, A Matsuda
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    ABSTRACT: We hypothesized that, because the stereoselectivity of anomeric radical reactions was significantly influenced by the anomeric effect, which can be controlled by restricting the conformation of the radical intermediate, the proper conformational restriction of the pyranose ring of the substrates would therefore make highly alpha- and beta-stereoselective anomeric radical reactions possible. Thus, the conformationally restricted 1-phenylseleno-D-xylose derivatives 9 and 10, restricted in a (4)C(1)-conformation, and 11 and 12, restricted in a (1)C(4)-conformation, were designed and synthesized by introducing the proper protecting groups on the hydroxyl groups on the pyranose ring as model substrates for the anomeric radical reactions. The radical deuterations with Bu(3)SnD and the C-glycosylation with Bu(3)SnCH(2)CH [double bond] CH(2) or CH(2) [double bond] CHCN, using the (4)C(1)-restricted substrates 9 and 10, afforded the corresponding alpha-products (alpha/beta = 97:3-85:15) highly stereoselectively, whereas the (1)C(4)-restricted substrates 11 and 12 selectively gave the beta-products (alpha/beta = 1:99-0:100). Thus, stereoselectivity was significantly increased by conformational restriction and was completely inverted by changing the substrate conformation from the (4)C(1)-form into the (1)C(4)-form. Ab initio calculations suggested that the radical intermediates produced from these substrates possessed the typical (4)C(1)- or (1)C(4)-conformation, which was similar to that of the substrates, and that the anomeric effect in these conformations would be the factor controlling the transition state of the reaction. Therefore, the highly alpha- and beta-selective reactions would occur because of the anomeric effect, which could be manipulated by conformational restriction of the substrates, as expected. This would be the first radical C-glycosylation reaction to provide both alpha- and beta-C-glycosides highly stereoselectively.
    Journal of the American Chemical Society 01/2002; 123(48):11870-82. · 10.68 Impact Factor
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    ABSTRACT: [Poly(ethyleneglycol)]-modified hemoglobin vesicles (PEG-HbV), a type of encapsulated hemoglobin, have been developed as artificial oxygen carriers and it is important to evaluate their blood compatibility. We studied the effects of PEG-HbV on human polymor phonuclear neutrophils (PMNs) in vitro, focusing on the functional responses to N-formyl-methionyl-leucyl-phenylalanine (fMLP) as an agonist. The pretreatment of the PMNs with PEG-HbV up to a concentration of 60 mg/dl Hb did not affect the fMLP-triggered chemotactic activity. In parallel to these results, the fMLP-induced upregulation of CD11b (Mac-1) levels on the PEG-HbV-pretreated PMNs was comparable to that of untreated cells. Furthermore, the pretreatment of the PMNs with the PEG-HbV even at 600 mg/dl Hb did not affect the gelatinase B (Matrix methalloproteinase-9 (MMP-9)) release, suggesting that the fMLP-induced release of secondary and tertiary granules was normal. In addition, the fMLP-triggered superoxide production of the PMNs was unchanged by the pretreatment with the PEG-HbV at 600 mg/dl Hb. Thus, these results suggest that PEG-HbV, at the concentrations studied, have no aberrant effects on the fMLP-triggered functions of human PMNs.
    Artificial Cells Blood Substitutes and Biotechnology 12/2001; 29(6):427-37. · 0.85 Impact Factor
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    ABSTRACT: We report a patient with persistent hyperplastic primary vitreous(PHPV) who presented with acute angle-closure glaucoma in his adult life. A 30-year-old man had an attack of acute angle-closure glaucoma associated with retrolenticular fibrous tissue, atrophic retina, and elongated cilliary process in his right eye. Ultrasound biomicroscopy(UBM) study showed iris bowing, shallow anterior chamber, and elongated cilliary body which were being pulled by the retrolenticular mass. The posterior chamber was normal. Although the mechanisms of secondary angle-closure glaucoma in PHPV are complicated, we suspected pupillary block resulting from constriction by the retrolenticular mass in this case.
    Nippon Ganka Gakkai zasshi 11/2001; 105(10):711-5.
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    ABSTRACT: To estimate retinal function in Bietti crystalline chorioretinal dystrophy using the electroretinogram. In this observational case series, the scotopic and photopic electroretinograms in three Japanese female patients (case 1, 55 years old; case 2, 56 years old; case 3, 47 years old) who showed bilateral crystalline retinal deposits but no corneal deposits were recorded. The rod and cone a-waves were analyzed by using the method described by Hood and Birch (1995, 1997). The parameters Rm(p3) (maximum a-wave amplitude) and S (sensitivity) were calculated. In case 1, the rod Rm(p3) was decreased in both eyes. The rod S in the right eye was within the normal range, but that in the left eye was significantly reduced. Although the cone Rm(p3) was decreased, the cone S was within the normal range. In case 2, the rod and cone Rm(p3) was reduced, but the rod and cone S was within the normal range in both eyes. In case 3, the rod and cone Rm(p3) and S were within the normal range. Electroretinograms illustrated different disease stages, however, no eye with normal Rm(p3) and decreased S was found in rods and cones. In the early stages of this disease, decreased numbers of photoreceptors and/or outer segment shortening may be present while phototransduction remains normal. As the damage to the retina progresses, phototransduction becomes severely affected. Because reduced cone S was not observed in our cases, cones may be less involved than rods in this disease.
    American Journal of Ophthalmology 10/2001; 132(3):395-402. · 3.63 Impact Factor
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    ABSTRACT: To increase the safety of stroma-free hemoglobin solution (SFH) as an artificial oxygen carrier source, we investigated the effect of heat treatment on virus inactivation in hemoglobin solution. The hemoglobin solution spiked with vesicular stomatitis virus (VSV) was treated at 60 degrees C for 1 hr under either an air or CO atmosphere. VSV was inactivated at >5.8 log10 and >6.0 log10 under the air and CO atmosphere, respectively. Although the methemoglobin rate increased after the heat treatment under the air atmosphere, no methemoglobin formation was observed by the treatment under the CO atmosphere. Isoelectric focusing analysis revealed the denaturation of hemoglobin after the heat treatment under the air, while hemoglobin banding was not altered in the carbonylated condition. Some protein bands other than hemoglobin were weakened or disappeared on SDS-PAGE after the heat treatment under both conditions. In addition, the hemoglobin concentration in the SFH was higher after the heat treatment than before the treatment. These findings indicate that the heat treatment under the CO atmosphere inactivates viruses without hemoglobin denaturation, and hence, this method is a promising approach to prepare a safer SFH as artificial oxygen carriers.
    Artificial Cells Blood Substitutes and Biotechnology 09/2001; 29(5):381-8. · 0.85 Impact Factor
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    ABSTRACT: The effect of virus inactivation by 1,9-dimethylmethylene blue (DMMB) phototreatment, methylene blue (MB) phototreatment or heat on the activities of antioxidant systems of stroma-free hemoglobin (SFH) was studied. DMMB photoinactivated human immunodeficiency virus by > 3.69 log10 under conditions that inactivated 3.33 log10 of vesicular stomatitis virus (VSV). Under conditions which inactivated VSV by 6.10 log10 (1.37 J/cm2 irradiation and 2 microM DMMB), there was little change in the methemoglobin (Met-Hb) formation, concentration of reduced glutathione (GSH), or superoxide dismutase (SOD), catalase (CAT) or glutathione peroxidase (GPX) activities. However, the activity of glutathione reductase (GR) was decreased by 77%. Under conditions that inactivated VSV by 5.69 log10 (1.37 J/cm2 irradiation and 24 microM MB) there was little effect of MB phototreatment on SOD, CAT, GPX and GSH activities. However, GR activity was decreased by 74% and Met-Hb content reached 3.98%. Under conditions that inactivated VSV by more than 6.20 log10 (60 degrees C for 2 min), virucidal heat treatment resulted in 27% Met-Hb formation and decreased GPX activity by 43%. No significant decline in SOD, CAT or GR activities or GSH concentration was observed. These results suggest that, compared with heat treatment and MB phototreatment, virucidal DMMB treatment preserves not only the oxidative state of hemoglobin but also the antioxidant systems against superoxide and hydrogen peroxide, although the reduced GR activity may limit the quenching capacity of antioxidants in DMMB-treated SFH.
    Photochemistry and Photobiology 09/2001; 74(3):461-4. · 2.29 Impact Factor
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    ABSTRACT: To report our surgical results of foveal translocation with scleral imbrication in patients with myopic neovascular maculopathy. Noncomparative, interventional, consecutive case series. Ten eyes of 10 myopic patients with subfoveal neovascular membranes that had undergone foveal translocation with scleral imbrication were recruited for this retrospective study. Inclusion criteria were myopia 6.0 diopters or greater in refractive error (or axial length 26.5 mm or longer), subfoveal choroidal neovascularization, and preoperative best-corrected visual acuity of 20/100 or worse. None of these eyes had undergone prior laser photocoagulation or submacular surgery. The main outcome measures were surgical complications and postoperative visual function. Postoperatively, visual acuity had improved more than 3 lines in the logarithm of minimum angle of resolution (logMAR) measurement in all eyes. The mean preoperative, postoperative best, and final visual acuity were 0.12, 0.59, and 0.51, respectively. Of the 10 eyes, six achieved a postoperative final visual acuity of 20/40 or better. The mean postoperative foveal displacement was 0.78 disk diameter (range, 0.3--1.3 disk diameter). Two patients underwent a reoperation because of insufficient foveal displacement. Furthermore, one of these two patients required a third operation to reduce an excessive retinal fold involving the fovea induced by the second surgery. Of the 10 patients, two noted transient diplopia. This complaint, however, resolved over time as suppression developed. Although unintentional iatrogenic retinal tears formed intraoperatively in two eyes, these were successfully treated without serious complications. Postoperatively, mild retinal pigment epithelial changes were observed in all cases, but none led to significant deterioration of visual acuity during the follow-up period. All patients but one were followed for a minimum of 6 months. In eyes with myopic neovascular maculopathy, foveal translocation with scleral imbrication may be useful in improving visual acuity. Further refinements in surgical technique and assessment of the long-term complications will be needed to make this procedure safer and more useful.
    American Journal of Ophthalmology 09/2001; 132(2):164-71. · 3.63 Impact Factor
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    ABSTRACT: We investigated the interactions between liposome-encapsulated hemoglobin (Neo Red Cells: NRC) and human polymorphonuclear leukocytes as assessed by superoxide generation. NRC triggered superoxide generation from neutrophils in a dose-dependent manner. Empty liposomes also induced superoxide production of neutrophils. Superoxide generation of neutrophils induced by phorbol myristate acetate (PMA) was delayed but intensified both by NRC and empty liposomes. The intensity of superoxide generation induced by NRC was smaller than that by the empty liposomes. As NRC contained superoxide dismutase (SOD) that was copurified with hemoglobin from red blood cells and its activity remained, SOD contained in NRC may partially eliminate superoxide.
    Artificial Cells Blood Substitutes and Biotechnology 08/2001; 29(4):275-83. · 0.85 Impact Factor
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    ABSTRACT: We studied the control of intraocular pressure(IOP) by various types of blebs after non-penetrating trabeculectomy(NPT) and the difference between bleb formation after penetrating trabeculectomy(PT) and that after NPT. The filtering blebs of 45 yeys from 40 patients after NPT were studied using ultrasound biomicroscopy. They were grouped into four types, and the space under the scleral flap was classified into three types. The filtering blebs and the space under the scleral flap were correlated with IOP level. Overall, 40% of the blebs were L(low-reflective) type, 16% H(high-reflective) type, 16% E (encapsulated) type, and 29% F(flattened) type, but in good IOP control cases 59% of the blebs were L type, 14% H type, 14% E type, and 14% F type. L type blebs were found in 94% of eyes with good IOP control. Though filtering blebs of the L type could produce sufficient IOP reduction, blebs after NPT showed a greater tendency to become flattened than after PT. Additional systematic therapy must be designed to maintain the L type of filtering blebs after NPT.
    Nippon Ganka Gakkai zasshi 08/2001; 105(7):447-51.
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    ABSTRACT: Vergence eye movements undergo adaptive recalibration in response to a training stimulus in which the initial disparity is changed just after vergence begins (the double-step paradigm). In the present study the changes in the dynamic properties of convergence, speed and acceleration, were examined by using this double-step paradigm, before and after adaptation. Four normal subjects participated. Three-dimensional visual stimuli were provided by a head-mounted display with two liquid crystal diode (LCD) panels. To induce adaptation, a double step of disparity was used: an initial step from distances of 2 to 1 m was followed by a second step to distances of 0.7 m ("increasing paradigm") or 1.4 m ("decreasing paradigm") after a constant period of 0.2 seconds. The dynamic properties of vergence were compared before and after 30 minutes of training with these paradigms. Peak velocity of convergence became significantly greater (increasing paradigm) or smaller (decreasing paradigm) after 30 minutes' training. Changes in the dynamic properties of convergence were also obvious in phase-plane (velocity versus position) and main sequence (peak velocity versus amplitude) plots. Further analysis revealed that adaptive increases in vergence velocity were accomplished by an increase in the duration of the acceleration period, whereas adaptive decreases were induced by a decrease in the maximum value of acceleration. The pattern of change in the dynamic characteristics of vergence after adaptation was similar to that of saccades and the initiation of pursuit eye movements, suggesting common neural mechanisms for adaptive changes in the open-loop control of eye movements.
    Investigative Ophthalmology &amp Visual Science 07/2001; 42(7):1479-86. · 3.44 Impact Factor
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    ABSTRACT: We studied the effects of hemoglobin-vesicles modified with PEG (PEG-HbV), a type of liposome-encapsulated hemoglobin (LEH), on human platelet functions in vitro. The effect of a low concentration of PEG-HbV (Hb; 5.8 mg/dl) was assessed by examining an agonist-induced aggregation response, and that of relatively high concentrations of PEG-HbV (Hb; 0.29, 1 and 2 g/dl) by measuring the release of RANTES (Regulated upon activation, normal T-cell expressed and presumably secreted) from platelets, which is regarded as a marker of platelet activation. The preincubation of platelets with PEG-HbV at 5.8 mg/dl of Hb did not affect platelet aggregation induced by collagen, thrombin and ristocetin. The pretreatment of platelet-rich plasma (PRP) with PEG-HbV at concen trations up to 2 g/dl of Hb had no aberrant effects on the collagen-induced RANTES release. Furthermore, the collagen-induced release of RANTES from PRP was not affected by longer incubation with PEG-HbV at 2 g/dl of Hb. The basal levels of RANTES from PRP were unchanged in the presence of PEG-HbV. These results suggest that PEG-HbV, at the concentrations studied, have no aberrant effects on platelet functions in the presence of plasma.
    Artificial Cells Blood Substitutes and Biotechnology 06/2001; 29(3):191-201. · 0.85 Impact Factor
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    ABSTRACT: To determine the role in the eye of chondromodulin (ChM)-I, which has been identified in cartilage as an angiogenic inhibitor, the expression and localization and a possible function of ChM-I were investigated. Expression and localization of ChM-I in rat eyes were examined by RNase protection assay and in situ hybridization and by immunostaining, using an antibody against a synthetic peptide. The effect of recombinant ChM-I on tube morphogenesis of retinal endothelial cells was examined in culture. The rat ChM-I gene was determined to encode the open reading frame of 334 amino acid residues, and ChM-I mRNA was exclusively expressed in cartilage, eye, and cerebellum in rats. ChM-I mRNA expression was evident in the iris-ciliary body, retina, and scleral compartments, but not in other compartments of the eye. In situ hybridization revealed mRNA expression in the ganglion cells, inner nuclear layer cells, and pigment epithelium in the retina and in the nonpigment epithelium of the ciliary body. Immunoreactive ChM-I was present in these cells and also in the vitreous body. Western blot analysis detected an approximately 25-kDa band of ChM-I presumed as a secretory form in the aqueous humor and vitreous body and an approximately 37-kDa band as a precursor form in the retina. Recombinant human ChM-I inhibited tube morphogenesis of human retinal endothelial cells in vitro. These observations indicate a potential role for ChM-I in inhibition of angiogenesis in the rat eye.
    Investigative Ophthalmology &amp Visual Science 06/2001; 42(6):1193-200. · 3.44 Impact Factor
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    ABSTRACT: The participation of reactive oxygen species (ROS) in virus inactivation by 1,9-dimethylmethylene blue (DMMB) phototreatment in stroma-free hemoglobin (SFH) was investigated with the use of scavengers, quenchers and enhancer. Virus (R17 bacteriophage) photoinactivation by either activated monomer or dimer DMMB was suppressed by sodium azide (singlet oxygen quencher) and promoted by the substitution of H2O for deuterium oxide (D2O), which is known to prolong the lifespan of singlet oxygen. There was no or little effect of mannitol (hydroxyl radical scavenger) and superoxide dismutase (superoxide scavenger) on the photoinactivation. Similar experiments were conducted to investigate the mechanism of methemoglobin (Met-Hb) formation by the activated monomer of DMMB. There was little effect of the singlet oxygen quencher, histidine, or the enhancer, D2O, on Met-Hb formation. However, rutin, which inhibits not only singlet oxygen but also other ROS, and mannitol supressed the formation of Met-Hb by activated monomer. The addition of superoxide dismutase (SOD) did not inhibit the formation. In contrast to the activity of the DMMB monomer, that of the dimer was inhibited by histidine and enhanced by D2O. The addition of neither mannitol nor SOD affected Met-Hb formation by activated dimer. These results collectively suggest that virus photoinactivation by the activated monomer and dimer of DMMB as well as Met-Hb formation by the activated dimer proceed via a singlet oxygen mediated pathway. In contrast, singlet oxygen may play a less important role in Met-Hb formation by the activated monomer.
    Biological & Pharmaceutical Bulletin 05/2001; 24(4):418-21. · 1.85 Impact Factor
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    ABSTRACT: The initial acceleration of pursuit in the open-loop period is under adaptive control and undergoes motor learning. The current study was undertaken to examine the hypothesis that the direction of pursuit initiation can also be adaptively modified. Four neurologically and ophthalmologically normal subjects participated in the experiment. A modified step-ramp paradigm was used to induce cross-axis adaptation, in which a ramp target changed its direction orthogonally just after the target crossed the center. Four direction changes were tested in separate experiments: left to up, left to down, down to left, and up to left. During a 30-minute adaptation session, the target moved in one of two randomly chosen directions (right to left or up to down) at one of two randomly chosen speeds (15.6 or 22.3 deg/sec), but the target changed orthogonally in only one direction. A linear regression fit to the initial 100-msec segment of the pursuit trace was used to determine the direction of pursuit initiation. In all cases, an adaptive change in pursuit initiation was gradually induced in the direction called for by the training paradigm. Adaptation was usually completed (90 degrees shift) within the 30-minute training session but declined quickly to an approximate 30 degrees -shift after training. The latency and vectorial amplitude of the initial acceleration remained unchanged. The adaptation was specific for the direction but not the velocity of the target. This study showed that the direction of pursuit initiation is under adaptive control, as has been shown for saccadic eye movements and the vestibulo-ocular reflex.
    Investigative Ophthalmology &amp Visual Science 04/2001; 42(3):668-74. · 3.44 Impact Factor
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    ABSTRACT: To investigate the usefulness of second-order multifocal electroretinograms (MERGs) for detecting inner retinal disorders. The MERG from 5 patients with branch retinal artery occlusion (BRAO) was recorded. Twelve eyes of 12 normal subjects were also tested. MERGs were recorded using 61 hexagons. Bright flash ERGs were also recorded to measure the oscillatory potentials (OP). Root mean square (RMS) measures of the local first- and second-order MERGs (fMERG and sMERG) were compared in the affected and unaffected areas. The first negative trough (N1) and first positive peak (P1) were also used for measuring the amplitudes and latencies of the fMERG. The fMERG RMS-amplitudes decreased significantly (r = 0.56, P: < 0.05) in the affected area compared with normal values. The fMERG latencies of N1 and P1 increased significantly (P: < 0.05) in the affected area. Furthermore, the sMERG RMS-amplitudes decreased almost to the noise level (r = 0.28, P: < 0.001) in the affected areas. The interocular ratio of the sMERG RMS-amplitudes (affected/normal) significantly correlated with that of the fMERG (r = 0.69, P: < 0.001). The fMERG latencies significantly correlated with the sMERG RMS-amplitude (r = 0.37 approximately 0.69, P: < 0.05 approximately 0.001), but only began to increase after a 30% to 50% loss of the sMERG amplitude. The summed OP amplitude decreased to the same extent as the sMERG in the affected eye (0.5 of the normal eye). Although the fMERG amplitude and latency were significantly changed, the sMERG was much more affected by BRAO. The marked reduction of the sMERG in the affected area strongly suggested its main source was from the more inner layers of the retina compared to the fMERG. The sMERG appeared to be a sensitive indicator of inner retinal dysfunction.
    Investigative Ophthalmology &amp Visual Science 02/2001; 42(1):298-304. · 3.44 Impact Factor

Publication Stats

1k Citations
214.20 Total Impact Points


  • 1993–2013
    • Niigata University
      • • Division of Ophthamology and Visual Sciences
      • • Department of Ophthalmology and Otolaryngology
      • • Faculty of Medicine
      • • School of Medicine
      Niahi-niigata, Niigata, Japan
  • 1999–2002
    • Hokkaido University
      • Graduate School of Pharmaceutical Sciences
      Sapporo-shi, Hokkaido, Japan
    • Showa University
      • First Department of Surgery
      Shinagawa, Tōkyō, Japan
  • 2000–2001
    • Japanese Red Cross
      Edo, Tōkyō, Japan
  • 1999–2000
    • Nihon Fukushi University
  • 1990–1999
    • St. Marianna University School of Medicine
      • Department of Cardiovascular Surgery
      Kawasaki Si, Kanagawa, Japan