Pei-Chang Wu

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

Are you Pei-Chang Wu?

Claim your profile

Publications (57)104.09 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: The aim of this study was to characterize stem cells from human exfoliated deciduous teeth (SHED) and to investigate the potential of SHED to differentiate toward corneal epithelium-like cells in vitro. Mesenchymal and embryonic stem cell markers were analyzed by flow cytometry. The SHED was cocultured in either a transwell noncontact system or in a mixed culture system with immortalized human corneal epithelial (HCE-T) cells to induce the epithelial transdifferentiation. Expression of the mature corneal epithelium-specific marker cytokeratin 3 (CK3) and corneal epithelial progenitor marker cytokeratin 19 (CK19) were detected by immunofluorescence and the reverse transcription-polymerase chain reaction, respectively. SHED strongly expressed a set of mesenchymal stromal cell markers and pluripotency markers including NANOG and OCT-4. Seven days after the transwells were cocultured with HCE-T cells, SHED successfully upregulated epithelial lineage markers CK3 (16.6 ± 7.9%) and CK19 (10.0 ± 4.3%) demonstrating the potential for epithelial transdifferentiation, whereas CK3 and CK19 were barely expressed in SHED when cultured alone. Expression of transcript levels of CK3 and CK19 were significantly upregulated when SHED were transwell cocultured or mixed cultured with HCE-T cells by 7, 14, and 21 days. We have demonstrated that SHED retain the potential for transdifferentiation to corneal epithelium-like cells by in vitro coculture with immortal corneal epithelium cells. Thus, exfoliated teeth may be an alternative tissue resource for providing stem cells for potential clinical applications in ocular surface regeneration.
    Cornea 07/2015; DOI:10.1097/ICO.0000000000000532 · 2.04 Impact Factor
  • [Show abstract] [Hide abstract]
    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 · 1.91 Impact Factor
  • [Show abstract] [Hide abstract]
    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 · 3.40 Impact Factor
  • Hsi-Kung Kuo · Yi-Hao Chen · Pei-Chang Wu · Yu-Hsia Kuo ·
    [Show abstract] [Hide abstract]
    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; 233. DOI:10.1159/000371901 · 1.68 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Purpose: Previously, we demonstrated that scleral stem/progenitor cells (SSPCs) from mice have a chondrogenic differentiation potential, which is stimulated by transforming growth factor-β (TGF-β). In the present study, we hypothesized that chondrogenesis in the sclera could be a possible mechanism in myopia development. Therefore, we investigated the association of form-deprivation myopia (FDM) with expressions in mice sclera representing the chondrogenic phenotype: collagen type II (Col2) and α-smooth muscle actin (α-SMA). Methods: The mRNA levels of α-SMA and Col2 in cultured murine SSPCs during chondrogenesis stimulated by TGF-β2 were determined by real-time quantitative RT–PCR (qRT-PCR). The expression patterns of α-SMA and Col2 were assessed by immunohistochemistry in a three dimensional pellet culture. In an FDM mouse model, a western blot analysis and immunofluorescence study were used to detect the changes in the α-SMA and Col2 protein expressions in the sclera. In the RPE-choroid complex, qRT-PCR was used to detect any changes in the TGF-β mRNA expression. Results: The treatment of SSPCs in vitro with TGF-β2 for 24 h at 1 or 10 ng/ml led to increased levels of both the α-SMA and Col2 expressions. In addition, we observed the formation of cartilage-like pellets from TGF-β2-treated SSPCs. Both α-SMA and Col2 were expressed in the pellet. In an in-vivo study, the α-SMA and Col2 protein expressions were significantly increased in the sclera of FDM eyes in comparison to contralateral control eyes. Similarly, the levels of TGF-β in the RPE-choroid complex of an FDM eye were also significantly elevated. Conclusion: Based on the concept of stem cells possessing multipotent differentiation potentials, scleral chondrogenesis induced by SSPCs may play a role in myopia development. The increased expressions of the cartilage-associated proteins Col2 and α-SMA during scleral chondrogenesis may be potential markers for myopia development. In addition, the increased levels of TGF-β mRNA in the RPE-choroid complex might induce the chondrogenic change in the sclera during myopia development.
    Molecular vision 02/2015; 21:138-147. · 1.99 Impact Factor
  • Source
    Pei-Chang Wu · Yi-Hsin Yang ·

    Ophthalmology 12/2013; DOI:10.1016/j.ophtha.2013.11.008 · 6.14 Impact Factor
  • [Show abstract] [Hide abstract]
    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.
    Taiwan Journal of Ophthalmology 12/2013; 3(4). DOI:10.1016/j.tjo.2013.10.005
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Boosting angiogenesis is a crucial process to enhance tissue growth in tissue engineering (TE). Hepatoma-derived growth factor (HDGF) has been identified as an angiogenic factor, but its involvement in angiogenesis in an arteriovenous loop-based TE chamber developed by the laboratory is unclear. In this study, the authors first examined the effects of HDGF on angiogenic responses in endothelial cells and in a corneal model of neovascularization, and then characterized the expression of HDGF in the TE chamber. HDGF (1–500 ng/mL) induced concentration-dependent angiogenic responses in human endothelial cells in vitro (proliferation, migration, and tube formation). Local application of HDGF stimulated neovascularization in a rat model of corneal angiogenesis. In the TE chamber, there was an increase in blood vessel volume from day 3 to day 14. Immunofluorescence microscopy revealed that HDGF is highly expressed in the neovessels in the chamber. Peak expression of HDGF (day 3) coincided with the infiltration of inflammatory cells, and the mRNA level of endogenous HDGF correlated with that of tumor necrosis factor α (TNFα). In vitro, TNFα stimulated HDGF expression in endothelial cells. The data suggest that HDGF may be involved in angiogenic responses in the TE chamber and the proinflammatory cytokine TNFα may have a pivotal role in stimulating HDGF expression. Enhancing HDGF signaling may be a new approach to extend vascularization for TE.
    Biomedical Engineering Applications Basis and Communications 10/2013; 25(05). DOI:10.4015/S1016237213400073 · 0.23 Impact Factor
  • [Show abstract] [Hide abstract]
    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.
    Taiwan Journal of Ophthalmology 06/2013; 3(2):58–61. DOI:10.1016/j.tjo.2013.03.001
  • Yu-Ti Teng · Chih-Hsin Chen · Jong-Jer Lee · Hsi-Kung Kuo · Pei-Chang Wu ·
    [Show abstract] [Hide abstract]
    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.
    Taiwan Journal of Ophthalmology 06/2013; 3(2):67–70. DOI:10.1016/j.tjo.2013.04.001
  • Source
    [Show abstract] [Hide abstract]
    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 · 6.14 Impact Factor
  • [Show abstract] [Hide abstract]
    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 · 1.47 Impact Factor
  • [Show abstract] [Hide abstract]
    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 glycated α- 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 · 2.82 Impact Factor
  • [Show abstract] [Hide abstract]
    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 · 3.40 Impact Factor
  • [Show abstract] [Hide abstract]
    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
  • [Show abstract] [Hide abstract]
    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 ·
    [Show abstract] [Hide abstract]
    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 · 1.47 Impact Factor
  • Chih-Hsin Chen · Pei-Chang Wu · Yung-Jen Chen · Ya-Chi Liu · Hsi-Kung Kuo ·
    [Show abstract] [Hide abstract]
    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 · 1.47 Impact Factor
  • Source
    Chia-Ling Tsai · Pei-Chang Wu · M Elizabeth Fini · Songtao Shi ·
    [Show abstract] [Hide abstract]
    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 · 3.40 Impact Factor
  • Source
    Pei-Chang Wu · Yung-Jen Chen · Hsi-Kung Kuo ·
    [Show abstract] [Hide abstract]
    ABSTRACT: A 78-year-old woman was diagnosed with fibrovascular pigment epithelial detachment (PED) associated with age-related macular degeneration (AMD) affecting both eyes. Due to decreased vision in her left eye (20/2000) and disease progression, the patient received 4 mg of triamcinolone acetonide (TA) by intravitreal injection into her left eye. There were no immediate post-injection complications in the left eye. However, one week later, a retinal pigment epithelial (RPE) tear, temporal-inferior to the fovea in the left eye, was noted and confirmed by fundus photography, fluorescein angiography and optical coherence tomography. In contrast, there no similar RPE tear occurred in her right eye after treated several times by intravitreous bevacizumab injection. Not only anti-vascular endothelium growth factor agents, but also intravitreal TA when used to treat AMD with PED, would seem to induce a RPE tear in the absence of previous or concurrent adjuvant therapy. Further investigations are required to confirm the mechanism by which the RPE tear occurs.
    Chang Gung medical journal 05/2011; 34(3):320-5.

Publication Stats

559 Citations
104.09 Total Impact Points


  • 2005-2015
    • Chang Gung Memorial Hospital
      • Department of Ophthalmology
      T’ai-pei, Taipei, Taiwan
  • 2006-2013
    • Chang Gung University
      • College of Medicine
      Hsin-chu-hsien, Taiwan, Taiwan
  • 2007
    • Kaohsiung Medical University
      • Department of Medicine
      Kao-hsiung-shih, Kaohsiung, Taiwan