Pei-Chang Wu

Chang Gung Memorial Hospital, T’ai-pei, Taipei, Taiwan

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Publications (55)104.47 Total impact

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    ABSTRACT: Proteins in the vitreous play an important role on the induction of proliferative vitreoretinopathy (PVR) after retinal detachment. The aim of this study was to investigate the variation of protein patterns in the vitreous of PVR eyes and examine whether differentially expressed protein levels were expressed in experimental PVR retina. Vitreous samples from PVR and macular hole patients were selected for proteomic analysis. The vitreous protein samples were separated by two-dimensional electrophoresis (2-DE). The differentially expressed protein spots in the two groups were excised and subjected to in-gel digestion and identification by electrospray ionization mass spectrometry (ESI-MS) analysis. Two differentially expressed proteins, zinc finger protein 670 (ZFP 670) and prostaglandin D2 synthase (PGD2S), were further validated by immunohistochemical staining and western blotting analysis in the retina of the experimental rabbit PVR model. In proteome analysis of human vitreous samples, five proteins had increased expression in PVR, including zinc finger protein 670 (ZFP 670), prostaglandin D2 synthase (PGD2S), IgG (Immunoglobulin G) light chain, transthyretin precursor, and haptoglobin precursor. ZFP 670 and PGD2S levels were expressed significantly higher in the experimental PVR retinas than in the control group. Levels of ZFP 670 and PGD2S were elevated in the vitreous fluid of patients with PVR. In addition, there were higher expressions of ZFP 670 and PGD2S in the experimental PVR retina. This result will expand our knowledge of pathophysiologic characteristics of PVR, and might be helpful for further developing possible treatment on this disorder.
    Albrecht von Graæes Archiv für Ophthalmologie 05/2015; DOI:10.1007/s00417-015-3022-2 · 2.33 Impact Factor
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    ABSTRACT: The pathophysiology of ocular hypertension (OH) leading to primary open angle glaucoma shares many features with a secondary form of OH caused by treatment with glucocorticoids, but also exhibits distinct differences. In this study, a pharmacogenomics approach was taken to discover candidate genes for this disorder. A genome-wide association study was performed, followed by an independent candidate gene study, using a cohort enrolled from patients treated with off-label intravitreal triamcinolone, and handling change in intraocular pressure as a quantitative trait. An intergenic quantitative trait locus (QTL) was identified at chromosome 6p21.33 near the 5' end of HCG22 that attained the accepted statistical threshold for genome-level significance. The HCG22 transcript, encoding a novel mucin protein, was expressed in trabecular meshwork cells and expression was stimulated by IL-1 and inhibited by triamcinolone acetate and TGF-beta. Bioinformatic analysis defined the QTL as an ~4 kilobase linkage disequilibrium block containing ten common single nucleotide polymorphisms (SNPs). Four of these SNPs were identified in NCBI's GTEx eQTL browser as modifiers of HCG22 expression. Most are predicted to disrupt or improve motifs for transcription factor binding, the most relevant being disruption of the glucocorticoid receptor binding motif. A second QTL was identified within the predicted signal peptide of the HCG22 encoded protein that could affect its secretion. Translation, O-glycosylation and secretion of the predicted HCG22 protein was verified in cultured trabecular meshwork cells. Identification of two independent QTLs that could affect expression of the HCG22 mucin gene product via two different mechanisms (transcription or secretion) is highly suggestive of a role in steroid-induced OH. Copyright © 2015 by Association for Research in Vision and Ophthalmology.
    Investigative ophthalmology & visual science 03/2015; 56(4). DOI:10.1167/iovs.14-14803 · 3.66 Impact Factor
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    ABSTRACT: Purpose: To investigate a new sustained-release formulation of dexamethasone (Ozurdex®) for inhibiting proliferative vitreoretinopathy (PVR) and its effect on the expression of retinal glial reaction and inflammation in experimental PVR eyes. Methods: We used 30 pigmented rabbits for this study. One week after gas compression, the eyes were injected with 5 × 10(4) retinal pigment epithelial cells into the vitreous cavity to induce PVR. Concurrently, one eye also received an intravitreal injection of Ozurdex; the other eye was used as a control. PVR was graded by indirect ophthalmoscopy on days 1, 3, 7, 14, 21, and 28. The expression of the retinal glial reaction and inflammation in experimental PVR eyes were evaluated by Western blot analysis. Results: PVR severity increased gradually and peaked after 14 days, and no differences in PVR severity between the study and control groups were observed at any time point. The expression of glial fibrillary acid protein (GFAP) increased on days 7 and 14 in both the PVR control and study groups. While the use of Ozurdex in the study group showed less GFAP expression, this difference was not significant. The expression of tumor necrosis factor (TNF)-α and interleukin (IL)-6 significantly increased on days 7 and 14 in PVR control eyes. There was a significant difference in TNF-α between PVR control eyes and Ozurdex-treated eyes on days 7 (p < 0.001) and 14 (p = 0.019). Ozurdex in the study group showed lower IL-6 expression; however, this difference was not significant on days 7 (p = 0.063) and 14 (p = 0.052). Conclusions: The intravitreal injection of Ozurdex suppressed the expression of inflammatory markers; however, it did not mitigate the severity of experimental PVR in this animal model. © 2015 S. Karger AG, Basel.
    Ophthalmologica 02/2015; DOI:10.1159/000371901 · 1.87 Impact Factor
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    Pei-Chang Wu, Yi-Hsin Yang
    Ophthalmology 12/2013; DOI:10.1016/j.ophtha.2013.11.008 · 6.17 Impact Factor
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    ABSTRACT: Purpose To study the long-term changes in refraction and visual outcome after extraction of congenital/ developmental cataracts and intraocular lens (IOL) implantation in children. Methods Cataract extraction and IOL implantation were performed in 33 eyes of 21 children aged 4–59 months. Refraction and best-corrected visual acuity (BCVA) were measured 4–5 years later. The cases were grouped by age at surgery: Group A: ≤1 year, Group B: 1–3 years, and Group C: >3 years. Results The mean myopic change was significantly lower in bilateral (mean −3.88 ± 2.47 D) than in unilateral (mean −7.68 ± 5.04 D) cases (p = 0.003). The latest BCVA values were logMAR 0.76 ± 0.86 and logMAR 0.43 ± 0.32 in unilateral and bilateral cases, respectively (p = 0.055). The mean myopic change values were −5.17 ± 4.49 D, −6.34 ± 3.44 D, and −3.45 ± 2.50 D in Groups A, B, and C, respectively (p = 0.104). The latest BCVA values were logMAR 0.84 ± 0.46, logMAR 0.55 ± 0.64, and logMAR 0.14 ± 0.17 in Groups A, B, and C, respectively (p = 0.035). Conclusion Best-corrected Snellen visual acuity ≥0.2 was achieved in most patients. We found less myopic shift in patients with bilateral cataracts and better visual outcomes in patients who underwent cataract surgery at older ages, probably because the cataracts in older patients were less dense initially and thus less likely to cause deprivation amblyopia.
    12/2013; DOI:10.1016/j.tjo.2013.10.005
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    ABSTRACT: Purpose To investigate patients with pterygium in different geographic regions and the associated risk factors in southern Taiwan. Methods A clinical observation survey was conducted in Chiayi County, a rural area in southern Taiwan. The subjects aged 40 years and above underwent complete ocular examinations. Associated risks factors were evaluated, including gender, age, occupations, smoking, and geographical living regions by univariant and multivariant logistic regression analysis. Results A total of 2197 participants (790 male, 36.0%) from 44 different villages were evaluated. In these, 554 participants (25.2%) have either unilateral or bilateral pterygium. Age is associated with the percentage of pterygium, and those aged between 60 and 69 had the highest percentage of 30.1% (p < 0.0001). The gender effect was higher among men than women (OR = 1.31, 95% CI: 1.08–1.60, p = 0.006). The percentage of pterygium lived in plain, seaside, and mountainous areas were 22.6%, 32.6%, and 14.5% respectively. Geographical regions also showed that seaside area had the highest percentage of pterygium (seaside area OR = 1.65, 95% CI: 1.35-2.03, and mountainous area OR = 0.58, 95% CI: 0.35-0.95 compared with plain areas). Primary outdoor workers and residents with smoking history had relative higher risk for pterygium (OR = 1.47, 95% CI: 1.17-1.86; OR = 1.36, 95% CI: 1.02-1.83). Conclusions The percentage of pterygium in southern Taiwan is about 25.2% among adults aged over 40 years in this survey. It is significantly higher in the age of 50 or more and in residents living in villages along the seaside than those living in the mountainous and the plain areas.
    06/2013; 3(2):58–61. DOI:10.1016/j.tjo.2013.03.001
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    ABSTRACT: Background/Purpose To evaluate the effect of intravitreal bevacizumab on subretinal fluid absorption in patients with chronic central serous chorioretinopathy (CSCR). Materials and methods This was a retrospective case series study. Patients with CSCR symptoms for > 3 months and who received intravitreal injection of bevacizumab were included. Ocular examinations were carried out at baseline and every follow-up visit, including visual acuity, fundus examination, and optic coherence tomography. Results Twelve eyes in 12 patients were included in this study. One month after injection, three of the 12 patients who had increased central macular thickness were considered nonresponders. Nine of the 12 patients who had decreased central macular thickness were considered to have responded to intravitreal bevacizumab injection. The response rate was 75%. In the response group, the mean central macular thickness significantly decreased, from 306.7 ± 77.8 μm to 204.3 ± 59.3 μm (p = 0.001) at 1 month. The mean Logarithm of the Minimum Angle of Resolution (logMAR) visual acuity was significantly improved from 0.72 ± 0.35 to 0.50 ± 0.28 (p = 0.008). Six of these nine patients had stable conditions lasting > 6 months. Three of them had recurrence. Conclusion Intravitreal bevacizumab injections improved subretinal fluid absorption in some patients with CSCR. It could be an alternative therapy for patients with CSCR, especially when they are not suitable for other treatments.
    06/2013; 3(2):67–70. DOI:10.1016/j.tjo.2013.04.001
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    ABSTRACT: PURPOSE: The aim of this study was to investigate the effect of outdoor activity during class recess on myopia changes among elementary school students in a suburban area of Taiwan. DESIGN: Prospective, comparative, consecutive, interventional study. PARTICIPANTS: Elementary school students 7 to 11 years of age recruited from 2 nearby schools located in a suburban area of southern Taiwan. INTERVENTION: The children of one school participated in the interventions, whereas those from the other school served as the control group. The interventions consisted of performing a recess outside the classroom (ROC) program that encouraged children to go outside for outdoor activities during recess. The control school did not have any special programs during recess. MAIN OUTCOME MEASURES: Data were obtained by means of a parent questionnaire and ocular evaluations that included axial length and cycloplegic autorefraction at the beginning and after 1 year. RESULTS: Five hundred seventy-one students were recruited for this study, of whom 333 students participated in the interventional program, and 238 students were in the control school. At the beginning of the study, there were no significant differences between these 2 schools with regard to age, gender, baseline refraction, and myopia prevalence (47.75% vs. 49.16%). After 1 year, new onset of myopia was significantly lower in the ROC group than in the control group (8.41% vs. 17.65%; P<0.001). There was also significantly lower myopic shift in the ROC group compared with the control group (-0.25 diopter [D]/year vs. -0.38 D/year; P = 0.029). The multivariate analysis demonstrated that the variables of intervention of the ROC program and higher school year proved to be a protective factor against myopia shift in nonmyopic subjects (P = 0.020 and P = 0.017, respectively). For myopic subjects, school year was the only variable significantly associated with myopia progression (P = 0.006). CONCLUSIONS: Outdoor activities during class recess in school have a significant effect on myopia onset and myopic shift. Such activities have a prominent effect on the control of myopia shift, especially in nonmyopic children. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.
    Ophthalmology 02/2013; 120(5). DOI:10.1016/j.ophtha.2012.11.009 · 6.17 Impact Factor
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    ABSTRACT: Abstract Purpose: To evaluate the impact of macular serous retinal detachment (SRD) and its relationship to treatment outcome after primary intravitreal bevacizumab (IVB) injection in patients with branch retinal vein occlusion (BRVO) and macular edema (ME). Methods: Seventy-three patients with ME secondary to BRVO who received primary IVB (2.5 mg/0.1 mL) were included in this study. The specific ME patterns were investigated using optical coherence tomography (OCT) examination. Visual acuity (VA), central macular thickness (CMT), and macular volume at baseline; at 1, 3, and 6 months; and at final visit after primary IVB were retrospectively analyzed and compared between patients with and without SRD. Results: SRD was found in 25 patients (34.2%). The baseline CMT was significantly thicker in patients with SRD than in those without SRD (648.4±200.5 μm vs. 440.3±119.6 μm, P<0.001). Six months after primary IVB injection, a greater reduction in CMT change from baseline was observed in the SRD group (412.5±227.2 μm) than in the group without SRD (118.5±175.2 μm) (P<0.001). The improvement of logarithm of the minimum angle of resolution VA was also greater in the SRD group than in the group without SRD (-0.64±0.52 and -0.28±0.62 respectively, P=0.015). Logistic regression analysis showed that the presence of SRD was an independent factor for visual improvement in BRVO (P=0.027). Conclusion: Patients with SRD had greater functional and morphological improvements at 6 months after primary IVB therapy. The results of this study suggest that the presence of SRD observed on OCT may be an indicator of favorable clinical response after IVB injections and that in BRVO patients with SRD, bevacizumab may be a good alternative for treatment.
    Journal of ocular pharmacology and therapeutics: the official journal of the Association for Ocular Pharmacology and Therapeutics 11/2012; 29(3). DOI:10.1089/jop.2012.0140 · 1.42 Impact Factor
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    ABSTRACT: BACKGROUND: Matrix-assisted laser desorption ionization/time-of-flight (MALDI-TOF) mass spectrometry is known as an extremely sensitive analytical tool for characterizing different types of biological compounds including proteins, peptides and lipids. Since MALDI-TOF analysis requires very simple sample pretreatment, the technique can be used for rapidly detecting biochemical compounds serving as disease biomarkers. RESULTS: This mini-review focuses on the applications of MALDI-TOF in the detection of potential disease biomarkers in various biological samples. CONCLUSIONS: The potential disease biomarkers are mostly abundant proteins, peptides, or lipids including: albumin; hemoglobin; α-defensins; trimethylamine; phospholipids; and glycatedα- and β-globin, which are indicators of albuminuria; fecal occult blood and ischemic stroke; dry eye disease and/or aging; trimethylaniuria; breast cancer; and diabetes, respectively.
    Clinica chimica acta; international journal of clinical chemistry 10/2012; 415. DOI:10.1016/j.cca.2012.10.032 · 2.76 Impact Factor
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    ABSTRACT: We investigated the therapeutic effect of liposomal doxorubicin (Lipo-dox) on experimental proliferative vitreoretinopathy (PVR). The toxicity of Lipo-dox was determined in vitro in cultured rabbit retinal pigment epithelium (RPE) cells by tetrazolium-based (MTT) assay for cell viability performed 48 and 96 hours after treatment, and in vivo by electroretinography and histopathology. The therapeutic effect of intravitreous injection of Lipo-dox was evaluated in a rabbit model of PVR induced by injection of rabbit RPE cells after gas compression of the vitreous. The presence of PVR was determined by indirect ophthalmoscopy on days 1, 7, 14, 21, and 28 after injection. Western blot and immunofluorescence studies were performed to evaluate the expression of the glial markers vimentin and glial fibrillary acidic protein (GFAP). A pharmacokinetic study also was performed and analyzed by liquid chromatography coupled with tandem mass spectrometry (LC-MS). The 50% inhibitory concentrations (IC₅₀) of doxorubicin (Doxo) and Lipo-dox in RPE cells were 0.01-0.1 and 0.1-1.0 μg/mL, respectively. Lipo-dox (10 μg/mL) did not reduce the amplitude reduction in the ERG study or produce obvious retinal toxicity. Lipo-dox still could be detected in the vitreous 7 days after injection. The Lipo-dox (10 μg/mL)-treated eyes showed lower grade PVR than did the untreated eyes. Lipo-dox also decreased the retinal expression levels of vimentin and GFAP. Lipo-dox can attenuate the severity of experimental PVR, and reduces the glial cell expression of intermediate filaments in PVR retinas. Lipo-dox has a wider safe dosage range and a longer half-life in the vitreous than does primary Doxo.
    Investigative ophthalmology & visual science 04/2012; 53(6):3167-74. DOI:10.1167/iovs.11-7972 · 3.66 Impact Factor
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    ABSTRACT: The authors demonstrate the feasibility and advantage of spectral-domain optical coherence tomography (SD-OCT) for single-shot ocular biometric measurement during the development of the mouse eye. A high-resolution SD-OCT system was built for single-shot imaging of the whole mouse eye in vivo. The axial resolution and imaging depth of the system are 4.5 μm (in tissue) and 5.2 mm, respectively. The system is capable of acquiring a cross-sectional OCT image consisting of 2,048 depth scans in 85 ms. The imaging capability of the SD-OCT system was validated by imaging the normal ocular growth and experimental myopia model using C57BL/6J mice. The biometric dimensions of the mouse eye can be calculated directly from one snapshot of the SD-OCT image. The biometric parameters of the mouse eye including axial length, corneal thickness, anterior chamber depth, lens thickness, vitreous chamber depth, and retinal thickness were successfully measured by the SD-OCT. In the normal ocular growth group, the axial length increased significantly from 28 to 82 days of age (P < .001). The lens thickness increased and the vitreous chamber depth decreased significantly during this period (P < .001 and P = .001, respectively). In the experimental myopia group, there were significant increases in vitreous chamber depth and axial length in comparison to the control eyes (P = .040 and P < .001, respectively). SD-OCT is capable of providing single-shot direct, fast, and high-resolution measurements of the dimensions of young and adult mouse eyes. As a result, SD-OCT is a potentially powerful tool that can be easily applied to research in eye development and myopia using small animal models.
    Ophthalmic Surgery Lasers and Imaging 03/2012; 43(3):252-6. DOI:10.3928/15428877-20120308-04 · 1.32 Impact Factor
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    ABSTRACT: In addition to the traditional lithotripsy treatment, extracorporeal shockwaves (ESWs) have been shown to be effective in the treatment of certain musculoskeletal disorders and in enhancing skin flap neovascularization. However, relatively little is known about its effect on melanocytes. To investigate its effect on the melanogenic activity of cultured melanocytes, mouse B16F10 melanocytes were treated with defocused ESWs of different energies (15, 21, and 27 kV) and at different doses (300 and 600 impulses). Cell viability was measured 1 and 24 h after treatment. Melanin content was measured and compared against a standard curve generated with fungal melanin. Cellular tyrosinase activity was calculated with the 3,4-dihydroxyphenylalanine (DOPA) oxidase assay. The results demonstrated that ESW treatment reduced cell viability. Our results also indicated that the overall decrease in cell viability lasted for 6 days. After ESW treatment with 300 or 600 impulses at 21 kV, no significant change in melanin content or tyrosinase activity of the B16F10 melanocytes was noted as compared to those of the control. The present study suggests that ESW treatment does not alter the melanogenic activity of the cultured melanocytes.
    Applied biochemistry and biotechnology 11/2011; 166(3):632-9. DOI:10.1007/s12010-011-9454-1 · 1.74 Impact Factor
  • Pei-Chang Wu, Yi-Hsin Yang, Po-Chiung Fang
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    ABSTRACT: The purpose of this article was to evaluate the long-term efficacy of a low-concentration (LC) atropine eye drop regimen (0.05%-0.1%) for controlling myopia progression in schoolchildren. This retrospective, case-control study enrolled myopic schoolchildren who had been followed-up for at least 3 years from 1999 to 2007. Children who received LC doses of atropine eye drops [initial prescription 0.05%, if progression over -0.5 diopter (D) during a 6-month follow-up then changed to 0.1% atropine] every night at bedtime were included in the LC atropine group, and untreated children served as controls. A total of 117 children were included in this study. The mean age was 8.4 years. There were 97 children in the LC atropine group and 20 children in the control group. The mean follow-up duration was 4.5 years. In a mixed model analysis, the adjusted myopia progression in the LC atropine group was -0.23 D/year, significantly lower than that of the control group, which was -0.86 D/year (P<0.001). About 80% of the treatment group had slow myopia progression (less than -0.5 D progression per year). In a multivariate analysis, factors such as initial spherical refraction with less myopia and treatment with LC atropine were significantly associated with less myopia progression, but age, sex, and initial astigmatism were not significantly associated (P<0.001, P<0.001, P=0.442, 0.494, and 0.547, respectively). The results of this study demonstrate that long-term and regular instillation of LC atropine eye drops is effective for controlling myopia progression and provides a possible strategy for an initial myopia regimen.
    Journal of ocular pharmacology and therapeutics: the official journal of the Association for Ocular Pharmacology and Therapeutics 08/2011; 27(5):461-6. DOI:10.1089/jop.2011.0027 · 1.42 Impact Factor
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    ABSTRACT: The purpose of this study was to evaluate the safety and efficacy of intravitreal bevacizumab in treatment-naive patients with choroidal neovascularization (CNV) secondary to pathologic myopia over a 2-year interval. Patients diagnosed with myopic CNV who had not received previous treatment were given intravitreal injections of bevacizumab (2.5 mg/0.1 mL). All patients were retrospectively evaluated using best-corrected visual acuity (BCVA) and central macular thickness (CMT) measured with optical coherence tomography (OCT). Twenty-six eyes of 26 patients aged 15-81 years (mean, 42.6 years) were enrolled. OCT images demonstrated that the mean CMT±standard deviation (SD) significantly changed from 270±47 μm at baseline to 228±35, 218±35, 212±25, 210±29, and 209±30 μm in the 1st, 3rd, 6th, 12th, and 24th post-treatment months, respectively (P<0.001 for all). The BCVA in logarithm of the minimum angle of resolution±SD significantly changed from 0.75±0.43 at baseline to 0.57±0.44, 0.42±0.44, 0.39±0.47, 0.41±0.44, and 0.42±0.41 in the 1st, 3rd, 6th, 12th, and 24th post-treatment months, respectively (P<0.001 for all). The mean number of injections was 1.69 (range, 1-4) within the 24-month period. The follow-up period ranged from 24 to 35 months (mean, 28 months). No other ocular or systemic adverse effects were observed. Although the present study lacked a control group, the results in this small series of patients over the 2-year follow-up period indicate that intravitreal injection of 2.5 mg bevacizumab is effective and safe in patients with myopic CNV.
    Journal of ocular pharmacology and therapeutics: the official journal of the Association for Ocular Pharmacology and Therapeutics 08/2011; 27(4):395-400. DOI:10.1089/jop.2011.0023 · 1.42 Impact Factor
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    ABSTRACT: The sclera forms the fibrous outer coat of the eyeball and acts as a supportive framework. The purpose of this study was to examine whether the sclera contains mesenchymal stem/progenitor cells. Scleral tissue from C57BL6/J mice was separated from the retina and choroid and subsequently enzyme digested to release single cells. Proliferation capacity, self-renewal capacity, and ability for multipotent differentiation were analyzed by BrdU labeling, flow cytometry, reverse transcriptase-polymerase chain reaction, immunocytochemistry, and in vivo transplantation. The scleral stem/progenitor cells (SSPCs) possessed clonogenic and high doubling capacities. These cells were positive for the mesenchymal markers Sca-1, CD90.2, CD44, CD105, and CD73 and negative for the hematopoietic markers CD45, CD11b, Flk1, CD34, and CD117. In addition to expressing stem cell genes ABCG2, Six2, Notch1, and Pax6, SSPCs were able to differentiate to adipogenic, chondrogenic, and neurogenic lineages. This study indicates that the sclera contains multipotent mesenchymal stem cells. Further study of SSPCs may help elucidate the cellular and molecular mechanism of scleral diseases such as scleritis and myopia.
    Investigative ophthalmology & visual science 07/2011; 52(8):5481-7. DOI:10.1167/iovs.11-7676 · 3.66 Impact Factor
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    ABSTRACT: We compared the Landolt C chart checked under normal clinical conditions and the Early Treatment of Diabetic Retinopathy Study (ETDRS) chart, using standard clinical research protocols for subjects with normal vision, cataract and maculopathy. This prospective, comparative study was approved by the hospital Institutional Review Board. Patients with cataract and maculopathy were included, with the normal fellow eyes analyzed as normal vision group. Differences between the two charts were analyzed using Student's t-test. Normal and cataract eyes showed no statistically significant differences between methods. In the maculopathy group, ETDRS acuity (0.714 ± 0.393) was better than Landolt C acuity (0.845 ± 0.579), but the differences were not statistically significant (p = 0.152). Furthermore, if after dividing visual acuity into subgroups, >20/200 and ≤20/200 by Landolt C acuity, the latter subgroup had significant differences between the two tests (p < 0.001). ETDRS acuity (1.014 ± 0.319) was better than Landolt C acuity (1.419 ± 0.385). The average acuity difference was 4 lines. For maculopathy patients with VA ≤ 20/200, the ETDRS chart had a better score than the Landolt C chart.
    Albrecht von Graæes Archiv für Ophthalmologie 04/2011; 249(4):601-5. DOI:10.1007/s00417-010-1461-3 · 2.33 Impact Factor
  • Chih-Hsin Chen, Pei-Chang Wu, Ya-Chi Liu
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    ABSTRACT: The purpose of this study was to evaluate the effects of intravitreal bevacizumab (ivBe) injection in patients with persistent macular edema after macular epiretinal membrane (ERM) removal. This retrospective study included 26 patients (26 eyes) with marked macular edema after complete removal of idiopathic macular ERM who received single ivBe injection (12 patients) or no treatment (controls, 14 patients). Main outcome measurements were central macular thickness (CMT) and best-corrected visual acuity (BCVA). In the ivBe group, the mean CMT±standard deviation (SD) changed significantly from 323±43 μm at baseline to 306±41, 301±42, and 296±41 μm at weeks 4, 8, and 12, respectively, after treatment (P= 0.025, <0.0001, and <0.0001, respectively). The BCVA in logarithm of the minimum angle of resolution (logMAR)±SD did not change significantly from 0.50±0.15 at baseline to 0.46±0.11, 0.44±0.14, 0.44±0.14, and 0.42±0.13 at weeks 1, 4, 8, and 12, respectively, after treatment (P>0.05 for all). In the control group, the mean CMT±SD changed significantly from 326±32 μm at baseline to 314±29, 308±29, and 307±30 μm at weeks 4, 8, and 12, respectively, after treatment (P=0.002, <0.0001, and <0.0001, respectively). The BCVA in logMAR±SD did not change significantly from 0.52±0.22 at baseline to 0.49±0.20, 0.47±0.22, 0.45±0.16, and 0.47±0.23 at modified weeks 1, 4, 8, and 12, respectively, after treatment (P>0.05 for all). No significant differences were found for CMT or BCVA between the ivBe group and the control group at baseline and at any checkpoints after treatment (P>0.05 for all). ivBe injection therapy provided no beneficial effects on CMT or visual acuity improvement for eyes with persistent macular edema after idiopathic macular ERM removal.
    Journal of ocular pharmacology and therapeutics: the official journal of the Association for Ocular Pharmacology and Therapeutics 03/2011; 27(3):287-92. DOI:10.1089/jop.2010.0166 · 1.42 Impact Factor
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    ABSTRACT: To investigate real-time intraocular pressure (IOP) during a new surgical technique-the "twisting maneuver"-when inserting a sutureless vitrectomy system trocar in porcine eyes. An interventional prospective study of 2 trocar insertion methods-direct insertion and gently twisting insertion-in a 25-gauge vitrectomy system (Alcon, Fort Worth, TX). These methods were used to create a scleral wound using a trocar blade and trocar cannula in freshly enucleated porcine eyes. The IOP changes induced by the procedures were recorded with a pressure transducer connected to the posterior chamber by direct cannulation. Fourteen porcine eyes were studied in each group. During insertion, the mean of highest IOP rise (peak IOP rise) was 63.9 ± 25.5 mmHg in the direct insertion group compared with 30.3 ± 16.9 mmHg in the twisting insertion group (P = 0.001). During insertion, the mean of average IOP rise in the direct insertion group was 39.9 ± 16.5 mmHg compared with 21.5 ± 8.9 mmHg in the twisting insertion group (P = 0.002). The total time needed to complete the procedure in the twisting insertion group was significantly longer than that in the direct insertion group (43.3 ± 21.8 vs. 14.9 ± 8.1 seconds, P = 0.0003). A simple modification of surgical technique, namely, using a gently twisting insertion maneuver during trocar insertion, could significantly reduce the IOP elevation to allow a safer sutureless vitrectomy.
    Retina (Philadelphia, Pa.) 02/2011; 31(5):887-92. DOI:10.1097/IAE.0b013e3181f57d8a · 3.18 Impact Factor
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    ABSTRACT: The potential peptidebiomarkers of dry eye disease were rapidly and sensitively screened in tears by simple sample pretreatment and modern mass spectrometry. The tear sample was collected by simply wiping the corner of the eye with a small piece of Schirmer filter paper from the patients confirmed to have dry eye disease and from normal controls. The peptides adsorbed on the filter paper were extracted by vortexing it with sinapinic acid solution in a vial. A drop of the extracted solution was then deposited on the sample plate and examined using matrix-assisted laser desorption ionization/time-of-flight mass spectrometry (MALDI-TOF MS) without any other sample pretreatment. We found human neutrophilpeptides (HNPs), so called α-defensins 1–3, which are potential biomarkers for inflammation, were significantly up-regulated in the tears collected from all the dry eye disease patients. The identity of the α-defensins in human tears was confirmed through (i) matching their molecular ions with those of standards, (ii) literature searches and (iii) electrophoretic purification and separation of the tears followed by in-gel tryptic digestion and MALDI-TOF analysis. The presence of large quantities of HNPs in the tears of dry eye patients suggests the occurrence of chronic inflammation in the ocular regions of dry eye patients.
    Analytical methods 12/2010; 2(12):1934-1940. DOI:10.1039/C0AY00243G · 1.94 Impact Factor

Publication Stats

444 Citations
104.47 Total Impact Points


  • 2005–2015
    • Chang Gung Memorial Hospital
      • Department of Ophthalmology
      T’ai-pei, Taipei, Taiwan
  • 2008–2013
    • Chang Gung University
      • College of Medicine
      Hsin-chu-hsien, Taiwan, Taiwan
  • 2007
    • Kaohsiung Medical University
      • Department of Medicine
      Kao-hsiung-shih, Kaohsiung, Taiwan