150 results on '"Yip SP"'
Search Results
2. Genome-wide association meta-analysis of corneal curvature identifies novel loci and shared genetic influences across axial length and refractive error
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Fan, Q, Pozarickij, A, Tan, NYQ, Guo, X, Verhoeven, VJM, Vitart, V, Guggenheim, JA, Miyake, M, Tideman, JWL, Khawaja, AP, Zhang, L, MacGregor, S, Hoehn, R, Chen, P, Biino, G, Wedenoja, J, Saffari, SE, Tedja, MS, Xie, J, Lanca, C, Wang, YX, Sahebjada, S, Mazur, J, Mirshahi, A, Martin, NG, Yazar, S, Pennell, CE, Yap, M, Haarman, AEG, Enthoven, CA, Polling, J, Hewitt, AW, Jaddoe, VWV, van Duijn, CM, Hayward, C, Polasek, O, Tai, E-S, Yoshikatsu, H, Hysi, PG, Young, TL, Tsujikawa, A, Wang, JJ, Mitchell, P, Pfeiffer, N, Parssinen, O, Foster, PJ, Fossarello, M, Yip, SP, Williams, C, Hammond, CJ, Jonas, JB, He, M, Mackey, DA, Wong, T-Y, Klaver, CCW, Saw, S-M, Baird, PN, Cheng, C-Y, Fan, Q, Pozarickij, A, Tan, NYQ, Guo, X, Verhoeven, VJM, Vitart, V, Guggenheim, JA, Miyake, M, Tideman, JWL, Khawaja, AP, Zhang, L, MacGregor, S, Hoehn, R, Chen, P, Biino, G, Wedenoja, J, Saffari, SE, Tedja, MS, Xie, J, Lanca, C, Wang, YX, Sahebjada, S, Mazur, J, Mirshahi, A, Martin, NG, Yazar, S, Pennell, CE, Yap, M, Haarman, AEG, Enthoven, CA, Polling, J, Hewitt, AW, Jaddoe, VWV, van Duijn, CM, Hayward, C, Polasek, O, Tai, E-S, Yoshikatsu, H, Hysi, PG, Young, TL, Tsujikawa, A, Wang, JJ, Mitchell, P, Pfeiffer, N, Parssinen, O, Foster, PJ, Fossarello, M, Yip, SP, Williams, C, Hammond, CJ, Jonas, JB, He, M, Mackey, DA, Wong, T-Y, Klaver, CCW, Saw, S-M, Baird, PN, and Cheng, C-Y
- Abstract
Corneal curvature, a highly heritable trait, is a key clinical endophenotype for myopia - a major cause of visual impairment and blindness in the world. Here we present a trans-ethnic meta-analysis of corneal curvature GWAS in 44,042 individuals of Caucasian and Asian with replication in 88,218 UK Biobank data. We identified 47 loci (of which 26 are novel), with population-specific signals as well as shared signals across ethnicities. Some identified variants showed precise scaling in corneal curvature and eye elongation (i.e. axial length) to maintain eyes in emmetropia (i.e. HDAC11/FBLN2 rs2630445, RBP3 rs11204213); others exhibited association with myopia with little pleiotropic effects on eye elongation. Implicated genes are involved in extracellular matrix organization, developmental process for body and eye, connective tissue cartilage and glycosylation protein activities. Our study provides insights into population-specific novel genes for corneal curvature, and their pleiotropic effect in regulating eye size or conferring susceptibility to myopia.
- Published
- 2020
3. IMI - Myopia Genetics Report
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Tedja, MS, Haarman, AEG, Meester-Smoor, MA, Kaprio, J, Mackey, DA, Guggenheim, JA, Hammond, CJ, Verhoeven, VJM, Klaver, CCW, Bailey-Wilson, JE, Baird, PN, Veluchamy, AB, Biino, G, Burdon, KP, Campbell, H, Chen, LJ, Cheng, C-Y, Chew, EY, Craig, JE, Cumberland, PM, Deangelis, MM, Delcourt, C, Ding, X, van Duijn, CM, Evans, DM, Fan, Q, Fossarello, M, Foster, PJ, Gharahkhani, P, Iglesias, AI, Guol, X, Haller, T, Han, X, Hayward, C, He, M, Hewitt, AW, Hoang, Q, Hysi, PG, Igo, RP, Iyengar, SK, Jonas, JB, Kahonen, M, Khawaja, AP, Klein, BE, Klein, R, Lass, JH, Lee, K, Lehtimaki, T, Lewis, D, Li, Q, Li, S-M, Lyytikainen, L-P, MacGregor, S, Martin, NG, Meguro, A, Metspalu, A, Middlebrooks, C, Miyake, M, Mizuki, N, Musolf, A, Nickels, S, Oexle, K, Pang, CP, Parssinen, O, Paterson, AD, Pfeiffer, N, Polasek, O, Rahi, JS, Raitakari, O, Rudan, I, Sahebjada, S, Saw, S-M, Stambolian, D, Simpson, CL, Tai, E-S, Tideman, JWL, Tsujikawa, A, Vitart, V, Wang, N, Wedenoja, J, Wei, WB, Williams, C, Williams, KM, Wilson, JF, Wojciechowski, R, Wang, YX, Yamashiro, K, Yam, JCS, Yap, MKH, Yazar, S, Yip, SP, Young, TL, Zhou, X, Tedja, MS, Haarman, AEG, Meester-Smoor, MA, Kaprio, J, Mackey, DA, Guggenheim, JA, Hammond, CJ, Verhoeven, VJM, Klaver, CCW, Bailey-Wilson, JE, Baird, PN, Veluchamy, AB, Biino, G, Burdon, KP, Campbell, H, Chen, LJ, Cheng, C-Y, Chew, EY, Craig, JE, Cumberland, PM, Deangelis, MM, Delcourt, C, Ding, X, van Duijn, CM, Evans, DM, Fan, Q, Fossarello, M, Foster, PJ, Gharahkhani, P, Iglesias, AI, Guol, X, Haller, T, Han, X, Hayward, C, He, M, Hewitt, AW, Hoang, Q, Hysi, PG, Igo, RP, Iyengar, SK, Jonas, JB, Kahonen, M, Khawaja, AP, Klein, BE, Klein, R, Lass, JH, Lee, K, Lehtimaki, T, Lewis, D, Li, Q, Li, S-M, Lyytikainen, L-P, MacGregor, S, Martin, NG, Meguro, A, Metspalu, A, Middlebrooks, C, Miyake, M, Mizuki, N, Musolf, A, Nickels, S, Oexle, K, Pang, CP, Parssinen, O, Paterson, AD, Pfeiffer, N, Polasek, O, Rahi, JS, Raitakari, O, Rudan, I, Sahebjada, S, Saw, S-M, Stambolian, D, Simpson, CL, Tai, E-S, Tideman, JWL, Tsujikawa, A, Vitart, V, Wang, N, Wedenoja, J, Wei, WB, Williams, C, Williams, KM, Wilson, JF, Wojciechowski, R, Wang, YX, Yamashiro, K, Yam, JCS, Yap, MKH, Yazar, S, Yip, SP, Young, TL, and Zhou, X
- Abstract
The knowledge on the genetic background of refractive error and myopia has expanded dramatically in the past few years. This white paper aims to provide a concise summary of current genetic findings and defines the direction where development is needed. We performed an extensive literature search and conducted informal discussions with key stakeholders. Specific topics reviewed included common refractive error, any and high myopia, and myopia related to syndromes. To date, almost 200 genetic loci have been identified for refractive error and myopia, and risk variants mostly carry low risk but are highly prevalent in the general population. Several genes for secondary syndromic myopia overlap with those for common myopia. Polygenic risk scores show overrepresentation of high myopia in the higher deciles of risk. Annotated genes have a wide variety of functions, and all retinal layers appear to be sites of expression. The current genetic findings offer a world of new molecules involved in myopiagenesis. As the missing heritability is still large, further genetic advances are needed. This Committee recommends expanding large-scale, in-depth genetic studies using complementary big data analytics, consideration of gene-environment effects by thorough measurement of environmental exposures, and focus on subgroups with extreme phenotypes and high familial occurrence. Functional characterization of associated variants is simultaneously needed to bridge the knowledge gap between sequence variance and consequence for eye growth.
- Published
- 2019
4. Meta-analysis of gene-environment-wide association scans accounting for education level identifies additional loci for refractive error
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Fan, Q, Verhoeven, VJM, Wojciechowski, R, Barathi, VA, Hysi, PG, Guggenheim, JA, Hoehn, R, Vitart, V, Khawaja, AP, Yamashiro, K, Hosseini, SM, Lehtimaki, T, Lu, Y, Haller, T, Xie, J, Delcourt, C, Pirastu, M, Wedenoja, J, Gharahkhani, P, Venturini, C, Miyake, M, Hewitt, AW, Guo, X, Mazur, J, Huffman, JE, Williams, KM, Polasek, O, Campbell, H, Rudan, I, Vatavuk, Z, Wilson, JF, Joshi, PK, McMahon, G, St Pourcain, B, Evans, DM, Simpson, CL, Schwantes-An, T-H, Igo, RP, Mirshahi, A, Cougnard-Gregoire, A, Bellenguez, C, Blettner, M, Raitakari, O, Kaehoenen, M, Seppala, I, Zeller, T, Meitinger, T, Ried, JS, Gieger, C, Portas, L, van Leeuwen, EM, Amin, N, Uitterlinden, AG, Rivadeneira, F, Hofman, A, Vingerling, JR, Wang, YX, Wang, X, Boh, ET-H, Ikram, MK, Sabanayagam, C, Gupta, P, Tan, V, Zhou, L, Ho, CEH, Lim, W, Beuerman, RW, Siantar, R, Tai, E-S, Vithana, E, Mihailov, E, Khor, C-C, Hayward, C, Luben, RN, Foster, PJ, Klein, BEK, Klein, R, Wong, H-S, Mitchell, P, Metspalu, A, Aung, T, Young, TL, He, M, Paerssinen, O, van Duijn, CM, Wang, JJ, Williams, C, Jonas, JB, Teo, Y-Y, David, AMM, Oexle, K, Yoshimura, N, Paterson, AD, Pfeiffer, N, Wong, T-Y, Baird, PN, Stambolian, D, Bailey-Wilson, JE, Cheng, C-Y, Hammond, CJ, Klaver, CCW, Saw, S-M, Rahi, JS, Korobelnik, J-F, Kemp, JP, Timpson, NJ, Smith, GD, Craig, JE, Burdon, KP, Fogarty, RD, Iyengar, SK, Chew, E, Janmahasatian, S, Martin, NG, MacGregor, S, Xu, L, Schache, M, Nangia, V, Panda-Jonas, S, Wright, AF, Fondran, JR, Lass, JH, Feng, S, Zhao, JH, Khaw, K-T, Wareham, NJ, Rantanen, T, Kaprio, J, Pang, CP, Chen, LJ, Tam, PO, Jhanji, V, Young, AL, Doering, A, Raffel, LJ, Cotch, M-F, Li, X, Yip, SP, Yap, MKH, Biino, G, Vaccargiu, S, Fossarello, M, Fleck, B, Yazar, S, Tideman, JWL, Tedja, M, Deangelis, MM, Morrison, M, Farrer, L, Zhou, X, Chen, W, Mizuki, N, Meguro, A, Makela, KM, Fan, Q, Verhoeven, VJM, Wojciechowski, R, Barathi, VA, Hysi, PG, Guggenheim, JA, Hoehn, R, Vitart, V, Khawaja, AP, Yamashiro, K, Hosseini, SM, Lehtimaki, T, Lu, Y, Haller, T, Xie, J, Delcourt, C, Pirastu, M, Wedenoja, J, Gharahkhani, P, Venturini, C, Miyake, M, Hewitt, AW, Guo, X, Mazur, J, Huffman, JE, Williams, KM, Polasek, O, Campbell, H, Rudan, I, Vatavuk, Z, Wilson, JF, Joshi, PK, McMahon, G, St Pourcain, B, Evans, DM, Simpson, CL, Schwantes-An, T-H, Igo, RP, Mirshahi, A, Cougnard-Gregoire, A, Bellenguez, C, Blettner, M, Raitakari, O, Kaehoenen, M, Seppala, I, Zeller, T, Meitinger, T, Ried, JS, Gieger, C, Portas, L, van Leeuwen, EM, Amin, N, Uitterlinden, AG, Rivadeneira, F, Hofman, A, Vingerling, JR, Wang, YX, Wang, X, Boh, ET-H, Ikram, MK, Sabanayagam, C, Gupta, P, Tan, V, Zhou, L, Ho, CEH, Lim, W, Beuerman, RW, Siantar, R, Tai, E-S, Vithana, E, Mihailov, E, Khor, C-C, Hayward, C, Luben, RN, Foster, PJ, Klein, BEK, Klein, R, Wong, H-S, Mitchell, P, Metspalu, A, Aung, T, Young, TL, He, M, Paerssinen, O, van Duijn, CM, Wang, JJ, Williams, C, Jonas, JB, Teo, Y-Y, David, AMM, Oexle, K, Yoshimura, N, Paterson, AD, Pfeiffer, N, Wong, T-Y, Baird, PN, Stambolian, D, Bailey-Wilson, JE, Cheng, C-Y, Hammond, CJ, Klaver, CCW, Saw, S-M, Rahi, JS, Korobelnik, J-F, Kemp, JP, Timpson, NJ, Smith, GD, Craig, JE, Burdon, KP, Fogarty, RD, Iyengar, SK, Chew, E, Janmahasatian, S, Martin, NG, MacGregor, S, Xu, L, Schache, M, Nangia, V, Panda-Jonas, S, Wright, AF, Fondran, JR, Lass, JH, Feng, S, Zhao, JH, Khaw, K-T, Wareham, NJ, Rantanen, T, Kaprio, J, Pang, CP, Chen, LJ, Tam, PO, Jhanji, V, Young, AL, Doering, A, Raffel, LJ, Cotch, M-F, Li, X, Yip, SP, Yap, MKH, Biino, G, Vaccargiu, S, Fossarello, M, Fleck, B, Yazar, S, Tideman, JWL, Tedja, M, Deangelis, MM, Morrison, M, Farrer, L, Zhou, X, Chen, W, Mizuki, N, Meguro, A, and Makela, KM
- Abstract
Myopia is the most common human eye disorder and it results from complex genetic and environmental causes. The rapidly increasing prevalence of myopia poses a major public health challenge. Here, the CREAM consortium performs a joint meta-analysis to test single-nucleotide polymorphism (SNP) main effects and SNP × education interaction effects on refractive error in 40,036 adults from 25 studies of European ancestry and 10,315 adults from 9 studies of Asian ancestry. In European ancestry individuals, we identify six novel loci (FAM150B-ACP1, LINC00340, FBN1, DIS3L-MAP2K1, ARID2-SNAT1 and SLC14A2) associated with refractive error. In Asian populations, three genome-wide significant loci AREG, GABRR1 and PDE10A also exhibit strong interactions with education (P<8.5 × 10(-5)), whereas the interactions are less evident in Europeans. The discovery of these loci represents an important advance in understanding how gene and environment interactions contribute to the heterogeneity of myopia.
- Published
- 2016
5. Genome-wide association study for refractive astigmatism reveals genetic co-determination with spherical equivalent refractive error: the CREAM consortium
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Li, Q, Wojciechowski, R, Simpson, CL, Hysi, PG, Verhoeven, VJM, Ikram, MK, Hoehn, R, Vitart, V, Hewitt, AW, Oexle, K, Makela, K-M, MacGregor, S, Pirastu, M, Fan, Q, Cheng, C-Y, St Pourcain, B, McMahon, G, Kemp, JP, Northstone, K, Rahi, JS, Cumberland, PM, Martin, NG, Sanfilippo, PG, Lu, Y, Wang, YX, Hayward, C, Polasek, O, Campbell, H, Bencic, G, Wright, AF, Wedenoja, J, Zeller, T, Schillert, A, Mirshahi, A, Lackner, K, Yip, SP, Yap, MKH, Ried, JS, Gieger, C, Murgia, F, Wilson, JF, Fleck, B, Yazar, S, Vingerling, JR, Hofman, A, Uitterlinden, A, Rivadeneira, F, Amin, N, Karssen, L, Oostra, BA, Zhou, X, Teo, Y-Y, Tai, ES, Vithana, E, Barathi, V, Zheng, Y, Siantar, RG, Neelam, K, Shin, Y, Lam, J, Yonova-Doing, E, Venturini, C, Hosseini, SM, Wong, H-S, Lehtimaki, T, Kahonen, M, Raitakari, O, Timpson, NJ, Evans, DM, Khor, C-C, Aung, T, Young, TL, Mitchell, P, Klein, B, van Duijn, CM, Meitinger, T, Jonas, JB, Baird, PN, Mackey, DA, Wong, TY, Saw, S-M, Parssinen, O, Stambolian, D, Hammond, CJ, Klaver, CCW, Williams, C, Paterson, AD, Bailey-Wilson, JE, Guggenheim, JA, Li, Q, Wojciechowski, R, Simpson, CL, Hysi, PG, Verhoeven, VJM, Ikram, MK, Hoehn, R, Vitart, V, Hewitt, AW, Oexle, K, Makela, K-M, MacGregor, S, Pirastu, M, Fan, Q, Cheng, C-Y, St Pourcain, B, McMahon, G, Kemp, JP, Northstone, K, Rahi, JS, Cumberland, PM, Martin, NG, Sanfilippo, PG, Lu, Y, Wang, YX, Hayward, C, Polasek, O, Campbell, H, Bencic, G, Wright, AF, Wedenoja, J, Zeller, T, Schillert, A, Mirshahi, A, Lackner, K, Yip, SP, Yap, MKH, Ried, JS, Gieger, C, Murgia, F, Wilson, JF, Fleck, B, Yazar, S, Vingerling, JR, Hofman, A, Uitterlinden, A, Rivadeneira, F, Amin, N, Karssen, L, Oostra, BA, Zhou, X, Teo, Y-Y, Tai, ES, Vithana, E, Barathi, V, Zheng, Y, Siantar, RG, Neelam, K, Shin, Y, Lam, J, Yonova-Doing, E, Venturini, C, Hosseini, SM, Wong, H-S, Lehtimaki, T, Kahonen, M, Raitakari, O, Timpson, NJ, Evans, DM, Khor, C-C, Aung, T, Young, TL, Mitchell, P, Klein, B, van Duijn, CM, Meitinger, T, Jonas, JB, Baird, PN, Mackey, DA, Wong, TY, Saw, S-M, Parssinen, O, Stambolian, D, Hammond, CJ, Klaver, CCW, Williams, C, Paterson, AD, Bailey-Wilson, JE, and Guggenheim, JA
- Abstract
To identify genetic variants associated with refractive astigmatism in the general population, meta-analyses of genome-wide association studies were performed for: White Europeans aged at least 25 years (20 cohorts, N = 31,968); Asian subjects aged at least 25 years (7 cohorts, N = 9,295); White Europeans aged <25 years (4 cohorts, N = 5,640); and all independent individuals from the above three samples combined with a sample of Chinese subjects aged <25 years (N = 45,931). Participants were classified as cases with refractive astigmatism if the average cylinder power in their two eyes was at least 1.00 diopter and as controls otherwise. Genome-wide association analysis was carried out for each cohort separately using logistic regression. Meta-analysis was conducted using a fixed effects model. In the older European group the most strongly associated marker was downstream of the neurexin-1 (NRXN1) gene (rs1401327, P = 3.92E-8). No other region reached genome-wide significance, and association signals were lower for the younger European group and Asian group. In the meta-analysis of all cohorts, no marker reached genome-wide significance: The most strongly associated regions were, NRXN1 (rs1401327, P = 2.93E-07), TOX (rs7823467, P = 3.47E-07) and LINC00340 (rs12212674, P = 1.49E-06). For 34 markers identified in prior GWAS for spherical equivalent refractive error, the beta coefficients for genotype versus spherical equivalent, and genotype versus refractive astigmatism, were highly correlated (r = -0.59, P = 2.10E-04). This work revealed no consistent or strong genetic signals for refractive astigmatism; however, the TOX gene region previously identified in GWAS for spherical equivalent refractive error was the second most strongly associated region. Analysis of additional markers provided evidence supporting widespread genetic co-susceptibility for spherical and astigmatic refractive errors.
- Published
- 2015
6. Genome-wide meta-analyses of multiancestry cohorts identify multiple new susceptibility loci for refractive error and myopia (vol 45, pg 314, 2013)
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Verhoeven, Virginie, Hysi, PG, Wojciechowski, R, Fan, Q, Guggenheim, JA, Hohn, R, Macgregor, S, Hewitt, AW, Nag, A, Cheng, CY (Ching-Yu), Yonova-Doing, E, Zhou, X, Ikram, Kamran, Buitendijk, Gabriëlle, McMahon, G, Kemp, JP, St Pourcain, B, Simpson, CL, Makela, KM, Lehtimaki, T, Kahonen, M, Paterson, AD, Hosseini, SM, Wong, HS, Xu, L, Jonas, JB, Parssinen, O, Wedenoja, J, Yip, SP, Ho, DWH, Pang, CP, Chen, LJ, Burdon, KP, Craig, JE, Klein, BEK, Klein, R, Haller, T, Metspalu, A, Khor, CC, Tai, ES, Aung, T, Vithana, E, Tay, WT, Barathi, VA, Chen, Peng, Li, RY, Liao, JM, Zheng, YF, Ong, RT, Doring, A, Evans, DM, Timpson, NJ, Verkerk, AJMH, Meitinger, T, Raitakari, O, Hawthorne, F, Spector, TD, Karssen, Lennart, Pirastu, M, Murgia, F, Ang, W, Mishra, A, Montgomery, GW, Pennell, CE, Cumberland, PM, Cotlarciuc, I, Mitchell, P, Wang, JJ, Schache, M, Janmahasathian, S, Igo, RP, Lass, JH, Chew, E, KIyengar, S, Gorgels, TGMF (Theo), Rudan, I, Hayward, C, Wright, AF, Polasek, O, Vatavuk, Z, Wilson, JF, Fleck, B, Zeller, T, Mirshahi, A, Müller, Caspar, Uitterlinden, André, Rivadeneira, Fernando, Vingerling, Hans, Hofman, Bert, Oostra, Ben, Amin, Najaf, Bergen, Arthur, Teo, YY, Rahi, JS, Vitart, V, Williams, C, Baird, PN, Wong, TY (Tien Yin), Oexle, K, Pfeiffer, N, Mackey, DA, Young, TL, Duijn, Cornelia, Saw, SM, Bailey-Wilson, JE, Stambolian, D, Klaver, Caroline, Hammond, CJ, Ophthalmology, Pathology, Epidemiology, Cell biology, Anesthesiology, Internal Medicine, Clinical Genetics, and Obstetrics & Gynecology
- Published
- 2013
7. Novel structural co-expression analysis linking the NPM1-associated ribosomal biogenesis network to chronic myelogenous leukemia
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Chan, Lawrence WC, primary, Lin, Xihong, additional, Yung, Godwin, additional, Lui, Thomas, additional, Chiu, Ya Ming, additional, Wang, Fengfeng, additional, Tsui, Nancy BY, additional, Cho, William CS, additional, Yip, SP, additional, Siu, Parco M., additional, Wong, SC Cesar, additional, and Yung, Benjamin YM, additional
- Published
- 2015
- Full Text
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8. Association of IGF1 gene haplotypes with high myopia in Chinese adults.
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Mak JY, Yap MK, Fung WY, Ng PW, and Yip SP
- Published
- 2012
9. TECHNICAL NOTE. INFLUENCE OF SPREADING OF CONCENTRATED LOADS ON STRESS RESULTANTS IN CIRCULAR RINGS.
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HAYDL, HM, primary and YIP, SP, additional
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- 1976
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10. Glaucoma Rehabilitation using ElectricAI Transcranial Stimulation (GREAT)-study protocol for randomized controlled trial using combined perceptual learning and transcranial electrical stimulation for vision enhancement.
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Jia S, Mei X, Chen L, Chan LH, Tsang C, Suen V, Li T, Zaw MW, Liu A, Thompson B, Sabel B, Woo G, Leung CKS, Yip SP, Chang DHF, and Cheong AMY
- Subjects
- Humans, Double-Blind Method, Visual Fields physiology, Randomized Controlled Trials as Topic, Treatment Outcome, Male, Middle Aged, Learning, Aged, Female, Vision, Ocular, Visual Perception, Recovery of Function, Transcranial Direct Current Stimulation methods, Quality of Life, Glaucoma physiopathology, Glaucoma rehabilitation
- Abstract
Background: Glaucoma patients with irreversible visual field loss often experience decreased quality of life, impaired mobility, and mental health challenges. Perceptual learning (PL) and transcranial electrical stimulation (tES) have emerged as promising interventions for vision rehabilitation, showing potential in restoring residual visual functions. The Glaucoma Rehabilitation using ElectricAI Transcranial stimulation (GREAT) project aims to investigate whether combining PL and tES is more effective than using either method alone in maximizing the visual function of glaucoma patients. Additionally, the study will assess the impact of these interventions on brain neural activity, blood biomarkers, mobility, mental health, quality of life, and fear of falling., Methods: The study employs a three-arm, double-blind, randomized, superiority-controlled design. Participants are randomly allocated in a 1:1:1 ratio to one of three groups receiving: (1) real PL and real tES, (2) real PL and sham tES, and (3) placebo PL and sham tES. Each participant undergoes 10 sessions per block (~ 1 h each), with a total of three blocks. Assessments are conducted at six time points: baseline, interim 1, interim 2, post-intervention, 1-month post-intervention, and 2-month post-intervention. The primary outcome is the mean deviation of the 24-2 visual field measured by the Humphrey visual field analyzer. Secondary outcomes include detection rate in the suprathreshold visual field, balance and gait functions, and electrophysiological and biological responses. This study also investigates changes in neurotransmitter metabolism, biomarkers, self-perceived quality of life, and psychological status before and after the intervention., Discussion: The GREAT project is the first study to assess the effectiveness of PL and tES in the rehabilitation of glaucoma. Our findings will offer comprehensive assessments of the impact of these treatments on a wide range of brain and vision-related metrics including visual field, neural activity, biomarkers, mobility, mental health, fear of falling, and quality of life., Trial Registration: ClinicalTrials.gov NCT05874258 . Registered on May 15, 2023., (© 2024. The Author(s).)
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- 2024
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11. Blood Biomarkers as Prognostic Indicators for Neurological Injury in COVID-19 Patients: A Systematic Review and Meta-Analysis.
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Huang Z, Haile K, Gedefaw L, Lau BW, Jin L, Yip SP, and Huang CL
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- Humans, Prognosis, Biomarkers, Glial Fibrillary Acidic Protein, Neurofilament Proteins, Intermediate Filaments metabolism, COVID-19 complications
- Abstract
Coronavirus disease 2019 (COVID-19) has been linked to various neurological complications. This meta-analysis assessed the relationship between glial fibrillary acidic protein (GFAP) and neurofilament light chain (NfL) levels in the blood and neurological injury in COVID-19 patients. A comprehensive search of various databases was conducted until 18 August 2023, to find studies reporting GFAP and NfL blood levels in COVID-19 patients with neurological complications. GFAP and NfL levels were estimated between COVID-19 patients and healthy controls, and meta-analyses were performed using RevMan 5.4 software for analysis. In the 21 collected studies, it was found that COVID-19 patients had significantly higher levels of pooled GFAP (SMD = 0.52; 95% CI: 0.31, 0.73; p ≤ 0.001) and NfL (SMD = 0.60; 95% CI: 0.37, 0.82; p ≤ 0.001) when compared to the healthy controls. The pooled GFAP (SMD = 0.86; 95% CI: 0.26, 1.45; p ≤ 0.01) and NfL (SMD = 0.87; 95% CI: 0.48, 1.26; p ≤ 0.001) were significantly higher in non-survivors. These findings indicate a significant association between COVID-19 severity and elevated levels of GFAP and NfL, suggesting that GFAP and NfL could serve as potential diagnostic and prognostic markers for the early detection and monitoring of COVID-19-related neurological injuries.
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- 2023
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12. Establishing Functional Retina in a Dish: Progress and Promises of Induced Pluripotent Stem Cell-Based Retinal Neuron Differentiation.
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Wong NK, Yip SP, and Huang CL
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- Animals, Humans, Retina, Cell Differentiation, Blindness, Induced Pluripotent Stem Cells, Retinal Neurons, Retinal Degeneration therapy
- Abstract
The human eye plays a critical role in vision perception, but various retinal degenerative diseases such as retinitis pigmentosa (RP), glaucoma, and age-related macular degeneration (AMD) can lead to vision loss or blindness. Although progress has been made in understanding retinal development and in clinical research, current treatments remain inadequate for curing or reversing these degenerative conditions. Animal models have limited relevance to humans, and obtaining human eye tissue samples is challenging due to ethical and legal considerations. Consequently, researchers have turned to stem cell-based approaches, specifically induced pluripotent stem cells (iPSCs), to generate distinct retinal cell populations and develop cell replacement therapies. iPSCs offer a novel platform for studying the key stages of human retinogenesis and disease-specific mechanisms. Stem cell technology has facilitated the production of diverse retinal cell types, including retinal ganglion cells (RGCs) and photoreceptors, and the development of retinal organoids has emerged as a valuable in vitro tool for investigating retinal neuron differentiation and modeling retinal diseases. This review focuses on the protocols, culture conditions, and techniques employed in differentiating retinal neurons from iPSCs. Furthermore, it emphasizes the significance of molecular and functional validation of the differentiated cells.
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- 2023
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13. Artificial Intelligence-Assisted Diagnostic Cytology and Genomic Testing for Hematologic Disorders.
- Author
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Gedefaw L, Liu CF, Ip RKL, Tse HF, Yeung MHY, Yip SP, and Huang CL
- Subjects
- Humans, Cytogenetics, Genetic Profile, Genetic Testing, Artificial Intelligence, Hematologic Diseases diagnosis, Hematologic Diseases genetics
- Abstract
Artificial intelligence (AI) is a rapidly evolving field of computer science that involves the development of computational programs that can mimic human intelligence. In particular, machine learning and deep learning models have enabled the identification and grouping of patterns within data, leading to the development of AI systems that have been applied in various areas of hematology, including digital pathology, alpha thalassemia patient screening, cytogenetics, immunophenotyping, and sequencing. These AI-assisted methods have shown promise in improving diagnostic accuracy and efficiency, identifying novel biomarkers, and predicting treatment outcomes. However, limitations such as limited databases, lack of validation and standardization, systematic errors, and bias prevent AI from completely replacing manual diagnosis in hematology. In addition, the processing of large amounts of patient data and personal information by AI poses potential data privacy issues, necessitating the development of regulations to evaluate AI systems and address ethical concerns in clinical AI systems. Nonetheless, with continued research and development, AI has the potential to revolutionize the field of hematology and improve patient outcomes. To fully realize this potential, however, the challenges facing AI in hematology must be addressed and overcome.
- Published
- 2023
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14. Amine-Functionalized Quantum Dots as a Universal Fluorescent Nanoprobe for a One-Step Loop-Mediated Isothermal Amplification Assay with Single-Copy Sensitivity.
- Author
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Wang S, Qin A, Chau LY, Fok EWT, Choy MY, Brackman CJ, Siu GKH, Huang CL, Yip SP, and Lee TMH
- Subjects
- Amines, Molecular Diagnostic Techniques, Nucleic Acid Amplification Techniques, Sensitivity and Specificity, Nucleic Acids, Quantum Dots
- Abstract
Loop-mediated isothermal amplification (LAMP) has received considerable attention for decentralized (point-of-care and on-site) nucleic acid testing in view of its simple temperature control (60-65 °C) and short assay time (15-60 min). There remains a challenge in its wide adoption and acceptance due to the limitations of the existing amplification result reporter probes, e.g., photobleaching of organic fluorophore and reduced sensitivity of the pH-sensitive colorimetric dye. Herein, we demonstrate CdSeS/ZnS quantum dots (semiconductor fluorescent nanocrystals with superior photostability than organic fluorophore) with surface modification of cysteamine (amine-QDs) as a new reporter probe for LAMP that enabled single-copy sensitivity (limit of detection of 83 zM; 20 μL reaction volume). For a negative LAMP sample (absence of target sequence), positively charged amine-QDs remained dispersed due to interparticle electrostatic repulsion. While for a positive LAMP sample (presence of target sequence), amine-QDs became precipitated. The characterization data showed that amine-QDs were embedded in magnesium pyrophosphate crystals (generated during positive LAMP), thus leading to their coprecipitation. This amine-QD-based one-step LAMP assay advances the field of QD-based nucleic acid amplification assays in two aspects: (1) compatibility─one-step amplification and detection (versus separation of amplification and detection steps); and (2) universality─the same amine-QDs for different target sequences (versus different oligonucleotide-modified QDs for different target sequences).
- Published
- 2022
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15. Transcriptional profiling of the chick retina identifies down-regulation of VIP and UTS2B genes during early lens-induced myopia.
- Author
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Shan SW, Wang PF, Cheung JKW, Yu F, Zheng H, Luo S, Yip SP, To CH, and Lam TC
- Subjects
- Animals, Chickens genetics, Chickens metabolism, Down-Regulation, Forkhead Transcription Factors genetics, Forkhead Transcription Factors metabolism, Nerve Tissue Proteins genetics, RNA, Messenger genetics, Retina metabolism, Intracellular Signaling Peptides and Proteins genetics, Myopia genetics, Myopia metabolism, Peptide Hormones genetics, Vasoactive Intestinal Peptide genetics
- Abstract
Gene expression of the chick retina was examined during the early development of lens-induced myopia (LIM) using whole transcriptome sequencing. Monocular treatment of the right eyes with -10 diopter (D) lenses was performed on newly born chicks for one day (LIM-24) or two days (LIM-48), while the contralateral eyes without lenses served as controls. Myopia development was confirmed by demonstrating significant elongation of the optical axis in lens-treated eyes compared to untreated control eyes. RNA was extracted and RNA-seq was performed using the Illumina HiSeq
TM 2000 platform. Data analysis was carried out on a Partek® Flow platform. Using screening criteria of ≥1.30-fold change and a false discovery rate <1%, 11 (five down-regulated and six up-regulated) and 35 differentially expressed genes (six down-regulated and twenty-nine up-regulated) were identified at 24 hours and 48 hours, respectively. Using another cohort for validation, Quantitative PCR confirmed significant changes in the expression of VIP and UTS2B mRNA ( P <0.05) after only 24 hours of LIM treatment and numerical changes in the expression for PCGF5 and FOXG1 , which were consistent with transcriptome sequencing but did not reach statistical significance. These data suggest that concerted changes of retinal gene expression may be instrumental in the initiation of axial elongation and myopia development.- Published
- 2022
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16. Targeting Inflammasome Activation in COVID-19: Delivery of RNA Interference-Based Therapeutic Molecules.
- Author
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Gedefaw L, Ullah S, Lee TMH, Yip SP, and Huang CL
- Abstract
Mortality and morbidity associated with COVID-19 continue to be significantly high worldwide, owing to the absence of effective treatment strategies. The emergence of different variants of SARS-CoV-2 is also a considerable source of concern and has led to challenges in the development of better prevention and treatment strategies, including vaccines. Immune dysregulation due to pro-inflammatory mediators has worsened the situation in COVID-19 patients. Inflammasomes play a critical role in modulating pro-inflammatory cytokines in the pathogenesis of COVID-19 and their activation is associated with poor clinical outcomes. Numerous preclinical and clinical trials for COVID-19 treatment using different approaches are currently underway. Targeting different inflammasomes to reduce the cytokine storm, and its associated complications, in COVID-19 patients is a new area of research. Non-coding RNAs, targeting inflammasome activation, may serve as an effective treatment strategy. However, the efficacy of these therapeutic agents is highly dependent on the delivery system. MicroRNAs and long non-coding RNAs, in conjunction with an efficient delivery vehicle, present a potential strategy for regulating NLRP3 activity through various RNA interference (RNAi) mechanisms. In this regard, the use of nanomaterials and other vehicle types for the delivery of RNAi-based therapeutic molecules for COVID-19 may serve as a novel approach for enhancing drug efficacy. The present review briefly summarizes immune dysregulation and its consequences, the roles of different non-coding RNAs in regulating the NLRP3 inflammasome, distinct types of vectors for their delivery, and potential therapeutic targets of microRNA for treatment of COVID-19.
- Published
- 2021
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17. The Tyrosine Kinase-Driven Networks of Novel Long Non-coding RNAs and Their Molecular Targets in Myeloproliferative Neoplasms.
- Author
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Wong NK, Luo S, Chow EYD, Meng F, Adesanya A, Sun J, Ma HMH, Jin W, Li WC, Yip SP, and Huang CL
- Abstract
Recent research has focused on the mechanisms by which long non-coding RNAs (lncRNAs) modulate diverse cellular processes such as tumorigenesis. However, the functional characteristics of these non-coding elements in the genome are poorly understood at present. In this study, we have explored several mechanisms that involve the novel lncRNA and microRNA (miRNA) axis participating in modulation of drug response and the tumor microenvironment of myeloproliferative neoplasms (MPNs). We identified novel lncRNAs via mRNA sequencing that was applied to leukemic cell lines derived from BCR-ABL1 -positive and JAK2 -mutant MPNs under treatment with therapeutic tyrosine kinase inhibitors (TKI). The expression and sequence of novel LNC000093 were further validated in both leukemic cells and normal primary and pluripotent cells isolated from human blood, including samples from patients with chronic myelogenous leukemia (CML). Downregulation of LNC000093 was validated in TKI-resistant CML while a converse expression pattern was observed in blood cells isolated from TKI-sensitive CML cases. In addition to BCR-ABL1 -positive CML cells, the driver mutation JAK2 -V617F-regulated lncRNA BANCR axis was further identified in BCR-ABL1 -negative MPNs. Further genome-wide validation using MPN patient specimens identified 23 unique copy number variants including the 7 differentially expressed lncRNAs from our database. The newly identified LNC000093 served as a competitive endogenous RNA for miR-675-5p and reversed the imatinib resistance in CML cells through regulating RUNX1 expression. The extrinsic function of LNC000093 in exosomal H19/miR-675-induced modulation for the microenvironment was also determined with significant effect on VEGF expression., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Wong, Luo, Chow, Meng, Adesanya, Sun, Ma, Jin, Li, Yip and Huang.)
- Published
- 2021
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18. Viral MicroRNAs Encoded by Nucleocapsid Gene of SARS-CoV-2 Are Detected during Infection, and Targeting Metabolic Pathways in Host Cells.
- Author
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Meng F, Siu GK, Mok BW, Sun J, Fung KSC, Lam JY, Wong NK, Gedefaw L, Luo S, Lee TMH, Yip SP, and Huang CL
- Subjects
- Animals, COVID-19 virology, Cell Line, Chlorocebus aethiops, Host-Pathogen Interactions, Humans, Phosphoproteins genetics, SARS-CoV-2 genetics, Vero Cells, COVID-19 metabolism, Coronavirus Nucleocapsid Proteins genetics, Metabolic Networks and Pathways, MicroRNAs genetics, RNA, Viral genetics, SARS-CoV-2 physiology
- Abstract
MicroRNAs (miRNAs) are critical regulators of gene expression that may be used to identify the pathological pathways influenced by disease and cellular interactions. Viral miRNAs (v-miRNAs) encoded by both DNA and RNA viruses induce immune dysregulation, virus production, and disease pathogenesis. Given the absence of effective treatment and the prevalence of highly infective SARS-CoV-2 strains, improved understanding of viral-associated miRNAs could provide novel mechanistic insights into the pathogenesis of COVID-19. In this study, SARS-CoV-2 v-miRNAs were identified by deep sequencing in infected Calu-3 and Vero E6 cell lines. Among the ~0.1% small RNA sequences mapped to the SARS-CoV-2 genome, the top ten SARS-CoV-2 v-miRNAs (including three encoded by the N gene; v-miRNA-N) were selected. After initial screening of conserved v-miRNA-N-28612, which was identified in both SARS-CoV and SARS-CoV-2, its expression was shown to be positively associated with viral load in COVID-19 patients. Further in silico analysis and synthetic-mimic transfection of validated SARS-CoV-2 v-miRNAs revealed novel functional targets and associations with mechanisms of cellular metabolism and biosynthesis. Our findings support the development of v-miRNA-based biomarkers and therapeutic strategies based on improved understanding of the pathophysiology of COVID-19.
- Published
- 2021
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19. Computer-assisted ultrasound assessment of plaque characteristics in radiation-induced and non-radiation-induced carotid atherosclerosis.
- Author
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Li Y, Kwong DL, Wu VW, Yip SP, Law HK, Lee SW, and Ying MT
- Abstract
Background: This study investigated the feasibility of using a computer-assisted method to evaluate and differentiate the carotid plaque characteristics in radiation-induced and non-radiation-induced carotid atherosclerosis., Methods: This study included 107 post-radiotherapy (post-RT) nasopharyngeal carcinoma (NPC) patients and 110 subjects with cardiovascular risk factors (CVRFs). Each participant had a carotid ultrasound examination, and carotid plaques and carotid intima-media thickness (CIMT) were evaluated with grey scale ultrasound. The carotid plaque characteristics were evaluated for grey-scale median (GSM) and detailed plaque texture analysis (DPTA) using specific computer software. In DPTA, five different intra-plaque components were colour-coded according to different grey scale ranges. A multivariate linear regression model was used to evaluate the correlation of risk factors and carotid plaque characteristics., Results: Post-RT NPC patients have significantly higher CIMT (748±15.1 µm, P=0.001), more patients had a plaque formation (80.4%, P<0.001) and more plaque locations (2.3±0.2, P<0.001) than CVRF subjects (680.4±10.0 µm, 38.2% and 0.5±0.1 respectively). Among the five intra-plaque components, radiation-induced carotid plaques had significantly larger area of calcification (4.8%±7.7%, P=0.012), but lesser area of lipid (42.1%±16.9%, P=0.034) when compared to non-radiation-induced carotid plaques (3.0%±5.7% and 46.3%±17.9% respectively). Age, radiation and number of CVRF were significantly associated with the carotid atherosclerosis burden (P<0.001). Besides, age was significantly associated with the amount of lipid and calcification within carotid plaques (P<0.001)., Conclusions: Radiation caused more severe carotid artery disease than CVRF with larger CIMT and more prevalent of carotid plaque. Radiation-induced carotid plaques tended to have more intra-plaque calcifications, whereas non-radiation-induced carotid plaques had more lipids. Ultrasound aided by computer-assisted image analysis has potential for more accurate assessment of carotid atherosclerosis., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at http://dx.doi.org/10.21037/qims-20-1012). The authors have no conflicts of interest to declare., (2021 Quantitative Imaging in Medicine and Surgery. All rights reserved.)
- Published
- 2021
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20. Inflammasome Activation-Induced Hypercoagulopathy: Impact on Cardiovascular Dysfunction Triggered in COVID-19 Patients.
- Author
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Gedefaw L, Ullah S, Leung PHM, Cai Y, Yip SP, and Huang CL
- Subjects
- Animals, COVID-19 immunology, COVID-19 pathology, Cardiovascular Diseases immunology, Cardiovascular Diseases pathology, Humans, NLR Family, Pyrin Domain-Containing 3 Protein immunology, SARS-CoV-2 immunology, Thrombophilia immunology, Thrombophilia pathology, COVID-19 complications, Cardiovascular Diseases etiology, Inflammasomes immunology, Thrombophilia etiology
- Abstract
Coronavirus disease 2019 (COVID-19) is the most devastating infectious disease in the 21st century with more than 2 million lives lost in less than a year. The activation of inflammasome in the host infected by SARS-CoV-2 is highly related to cytokine storm and hypercoagulopathy, which significantly contribute to the poor prognosis of COVID-19 patients. Even though many studies have shown the host defense mechanism induced by inflammasome against various viral infections, mechanistic interactions leading to downstream cellular responses and pathogenesis in COVID-19 remain unclear. The SARS-CoV-2 infection has been associated with numerous cardiovascular disorders including acute myocardial injury, myocarditis, arrhythmias, and venous thromboembolism. The inflammatory response triggered by the activation of NLRP3 inflammasome under certain cardiovascular conditions resulted in hyperinflammation or the modulation of angiotensin-converting enzyme 2 signaling pathways. Perturbations of several target cells and tissues have been described in inflammasome activation, including pneumocytes, macrophages, endothelial cells, and dendritic cells. The interplay between inflammasome activation and hypercoagulopathy in COVID-19 patients is an emerging area to be further addressed. Targeted therapeutics to suppress inflammasome activation may have a positive effect on the reduction of hyperinflammation-induced hypercoagulopathy and cardiovascular disorders occurring as COVID-19 complications.
- Published
- 2021
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21. Vascular Tissue Engineering: Advanced Techniques and Gene Editing in Stem Cells for Graft Generation.
- Author
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Chen SG, Ugwu F, Li WC, Caplice NM, Petcu E, Yip SP, and Huang CL
- Subjects
- Animals, Blood Vessel Prosthesis, Printing, Three-Dimensional, Stem Cells, Gene Editing, Tissue Engineering
- Abstract
The common occurrence of cardiovascular diseases and the lack of proper autologous tissues prompt and promote the pressing development of tissue-engineered vascular grafts (TEVGs). Current progress on scaffold production, genetically modified cells, and use of nanotechnology-based monitoring has considerably improved the long-term patency of engineered tissue grafts. However, challenges abound in the autologous materials and manipulation of genes and cells for tissue engineering. This review overviews current development in TEVGs and discusses recent improvements in scaffolding techniques and the efficiency of gene-editing tools and their ability to fill the existing gaps in stem cell and regenerative therapies. Current advances in three-dimensional printing approaches for fabrication of engineered tissues are also reviewed together with specific biomaterials for vascular tissues. In addition, the natural and synthetic polymers that hold increasing significance for vascular tissue engineering are highlighted. Both animal models and nanotechnology-based monitoring are proposed for preclinical evaluation of engineered grafts in view of their historical significance in tissue engineering. The ultimate success of tissue regeneration, which is yet to be fully realized, depends on the optimal performance of culture systems, biomaterial constructs, and stem cells in a suitable artificial physiological environment.
- Published
- 2021
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22. Territorywide Study of Early Coronavirus Disease Outbreak, Hong Kong, China.
- Author
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Leung KS, Ng TT, Wu AK, Yau MC, Lao HY, Choi MP, Tam KK, Lee LK, Wong BK, Man Ho AY, Yip KT, Lung KC, Liu RW, Tso EY, Leung WS, Chan MC, Ng YY, Sin KM, Fung KS, Chau SK, To WK, Que TL, Shum DH, Yip SP, Yam WC, and Siu GK
- Subjects
- Adult, Aged, Aged, 80 and over, COVID-19 transmission, Cluster Analysis, Disease Hotspot, Evolution, Molecular, Female, Hong Kong epidemiology, Humans, Male, Middle Aged, Mutation, Phylogeny, Phylogeography, SARS-CoV-2 genetics, SARS-CoV-2 isolation & purification, Viroporin Proteins genetics, Whole Genome Sequencing, Young Adult, COVID-19 epidemiology, COVID-19 virology, Disease Outbreaks
- Abstract
Initial cases of coronavirus disease in Hong Kong were imported from mainland China. A dramatic increase in case numbers was seen in February 2020. Most case-patients had no recent travel history, suggesting the presence of transmission chains in the local community. We collected demographic, clinical, and epidemiologic data from 50 patients, who accounted for 53.8% of total reported case-patients as of February 28, 2020. We performed whole-genome sequencing to determine phylogenetic relationship and transmission dynamics of severe acute respiratory syndrome coronavirus 2 infections. By using phylogenetic analysis, we attributed the community outbreak to 2 lineages; 1 harbored a common mutation, Orf3a-G251V, and accounted for 88.0% of the cases in our study. The estimated time to the most recent common ancestor of local coronavirus disease outbreak was December 24, 2019, with an evolutionary rate of 3.04 × 10
-3 substitutions/site/year. The reproduction number was 1.84, indicating ongoing community spread.- Published
- 2021
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23. Will a new clade of SARS-CoV-2 imported into the community spark a fourth wave of the COVID-19 outbreak in Hong Kong?
- Author
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Siu GK, Lee LK, Leung KS, Leung JS, Ng TT, Chan CT, Tam KK, Lao HY, Wu AK, Yau MC, Lai YW, Fung KS, Chau SK, Wong BK, To WK, Luk K, Ho AY, Que TL, Yip KT, Yam WC, Shum DH, and Yip SP
- Subjects
- Disease Outbreaks, Hong Kong epidemiology, Humans, COVID-19 epidemiology, SARS-CoV-2 genetics
- Published
- 2020
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24. Geographical accessibility of community social services and incidence of self-harm.
- Author
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Leung M, Chow CB, Ip PP, and Yip SP
- Subjects
- Adolescent, Adult, Age Factors, Aged, Female, Hong Kong epidemiology, Humans, Incidence, Male, Young Adult, Community Health Services methods, Health Services Accessibility statistics & numerical data, Self-Injurious Behavior epidemiology, Social Work methods, Spatial Analysis
- Abstract
Objective: The study aimed to explore the association between area-based coverage of community services and the incidence of self-harm, which will provide an evaluation framework for the support of self-harm., Methods: Enhanced two-Step floating catchment area method was used to estimate the centersto- population ratio and geographical accessibility adjusted by a distance-decay function. Spearman's rank coefficient was used to examine the association between the self-harm rate and adjusted accessibility index., Results: There was a significant negative correlation between the accessibility index and selfharm rate in youth (rho = -0.87, P < 0.01) and older adults (rho = -0.87, P < 0.01). The survival curves showed no relationship between self-harm repetition and service accessibility in youth or older adults., Conclusions: The uneven spatial accessibility of community social service centers and the independence between spatial accessibility and self-harm highlights the need to explore personal barriers to community service utilization., (Copyright © 2020. Published by Elsevier Ltd.)
- Published
- 2020
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25. Genome-wide association meta-analysis of corneal curvature identifies novel loci and shared genetic influences across axial length and refractive error.
- Author
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Fan Q, Pozarickij A, Tan NYQ, Guo X, Verhoeven VJM, Vitart V, Guggenheim JA, Miyake M, Tideman JWL, Khawaja AP, Zhang L, MacGregor S, Höhn R, Chen P, Biino G, Wedenoja J, Saffari SE, Tedja MS, Xie J, Lanca C, Wang YX, Sahebjada S, Mazur J, Mirshahi A, Martin NG, Yazar S, Pennell CE, Yap M, Haarman AEG, Enthoven CA, Polling J, Hewitt AW, Jaddoe VWV, van Duijn CM, Hayward C, Polasek O, Tai ES, Yoshikatsu H, Hysi PG, Young TL, Tsujikawa A, Wang JJ, Mitchell P, Pfeiffer N, Pärssinen O, Foster PJ, Fossarello M, Yip SP, Williams C, Hammond CJ, Jonas JB, He M, Mackey DA, Wong TY, Klaver CCW, Saw SM, Baird PN, and Cheng CY
- Subjects
- Asian People genetics, Databases, Genetic, Gene Regulatory Networks, Genetic Predisposition to Disease, Genome-Wide Association Study, Humans, Myopia ethnology, Myopia pathology, Phenotype, Refractometry, Risk Assessment, Risk Factors, White People genetics, Axial Length, Eye pathology, Cornea pathology, Corneal Topography, Genetic Loci, Myopia genetics, Polymorphism, Single Nucleotide
- Abstract
Corneal curvature, a highly heritable trait, is a key clinical endophenotype for myopia - a major cause of visual impairment and blindness in the world. Here we present a trans-ethnic meta-analysis of corneal curvature GWAS in 44,042 individuals of Caucasian and Asian with replication in 88,218 UK Biobank data. We identified 47 loci (of which 26 are novel), with population-specific signals as well as shared signals across ethnicities. Some identified variants showed precise scaling in corneal curvature and eye elongation (i.e. axial length) to maintain eyes in emmetropia (i.e. HDAC11/FBLN2 rs2630445, RBP3 rs11204213); others exhibited association with myopia with little pleiotropic effects on eye elongation. Implicated genes are involved in extracellular matrix organization, developmental process for body and eye, connective tissue cartilage and glycosylation protein activities. Our study provides insights into population-specific novel genes for corneal curvature, and their pleiotropic effect in regulating eye size or conferring susceptibility to myopia.
- Published
- 2020
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26. The myopia susceptibility locus vasoactive intestinal peptide receptor 2 (VIPR2) contains variants with opposite effects.
- Author
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Leung KH, Luo S, Kwarteng R, Chen SG, Yap MKH, Huang CL, and Yip SP
- Subjects
- Adult, Alleles, Asian People genetics, Case-Control Studies, Cohort Studies, Female, Genotype, Haplotypes genetics, Humans, Linkage Disequilibrium genetics, Male, Genetic Predisposition to Disease genetics, Myopia, Degenerative genetics, Polymorphism, Single Nucleotide genetics, Receptors, Vasoactive Intestinal Peptide, Type II genetics
- Abstract
Myopia is the commonest eye disorder in the world. High myopes are predisposed to ocular pathologies. The vasoactive intestinal peptide receptor 2 (VIPR2) gene was identified as a myopia susceptibility locus by our group and another group. We continued to fine-map this locus. A case-control study was performed in 4 sequential stages with a total of 941 highly myopic subjects and 846 control subjects, all unrelated Chinese. Stage 1 experimentally genotyped 64.4% of the entire cohort for 152 single-nucleotide polymorphisms (SNPs) and Stage 2 the remaining subjects for 21 SNPs. Stage 3 combined the genotypes for 21 SNPs for the entire cohort, and identified one group of high-risk haplotypes and one group of protective haplotypes significantly associated with high myopia. Stage 4 imputed genotypes for variants in the VIPR2 region and identified two independent groups of variants: one group with high-risk minor alleles and another with protective minor alleles. Variants within each group were generally in strong linkage disequilibrium among themselves while high-risk variants were in linkage equilibrium with protective variants. Therefore, the VIPR2 locus seems to contain variants with opposite effects. This is the first study that has examined the genetic architecture of a myopia susceptibility locus in detail.
- Published
- 2019
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27. DNA sequence patterns in human major histocompatibility complex region in southern Chinese.
- Author
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Song YQ, Sham PS, Yip SP, Fan YH, and Bao SY
- Subjects
- Aged, Aged, 80 and over, Base Sequence, Female, Humans, Male, Linkage Disequilibrium, Major Histocompatibility Complex genetics, Polymorphism, Single Nucleotide
- Published
- 2019
28. A Genome-Wide Association Study for Susceptibility to Visual Experience-Induced Myopia.
- Author
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Huang Y, Kee CS, Hocking PM, Williams C, Yip SP, and Guggenheim JA
- Subjects
- Adolescent, Animals, Animals, Newborn, Axial Length, Eye pathology, Chickens, Child, Databases, Factual, Disease Models, Animal, Female, Gene-Environment Interaction, Genotyping Techniques, Humans, Longitudinal Studies, Male, Middle Aged, Sensory Deprivation, Class Ib Phosphatidylinositol 3-Kinase genetics, Cyclic AMP-Dependent Protein Kinase RIIbeta Subunit genetics, Genetic Predisposition to Disease genetics, Genome-Wide Association Study methods, Myopia genetics, Visual Perception genetics
- Abstract
Purpose: The rapid rise in prevalence over recent decades and high heritability of myopia suggest a role for gene-environment (G × E) interactions in myopia susceptibility. Few such G × E interactions have been discovered to date. We aimed to test the hypothesis that genetic analysis of susceptibility to visual experience-induced myopia in an animal model would identify novel G × E interaction loci., Methods: Chicks aged 7 days (n = 987) were monocularly deprived of form vision for 4 days. A genome-wide association study (GWAS) was carried out in the 20% of chicks most susceptible and least susceptible to form deprivation (n = 380). There were 304,963 genetic markers tested for association with the degree of induced axial elongation in treated versus control eyes (A-scan ultrasonography). A GWAS candidate region was examined in the following three human cohorts: CREAM consortium (n = 44,192), UK Biobank (n = 95,505), and Avon Longitudinal Study of Parents and Children (ALSPAC; n = 4989)., Results: A locus encompassing the genes PIK3CG and PRKAR2B was genome-wide significantly associated with myopia susceptibility in chicks (lead variant rs317386235, P = 9.54e-08). In CREAM and UK Biobank GWAS datasets, PIK3CG and PRKAR2B were enriched for strongly-associated markers (meta-analysis lead variant rs117909394, P = 1.7e-07). In ALSPAC participants, rs117909394 had an age-dependent association with refractive error (-0.22 diopters [D] change over 8 years, P = 5.2e-04) and nearby variant rs17153745 showed evidence of a G × E interaction with time spent reading (effect size -0.23 D, P = 0.022)., Conclusions: This work identified the PIK3CG-PRKAR2B locus as a mediator of susceptibility to visually induced myopia in chicks and suggests a role for this locus in conferring susceptibility to myopia in human cohorts.
- Published
- 2019
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29. Self-harm attempters' perception of community services and its implication on service provision.
- Author
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Leung M, Chow CB, Ip PP, and Yip SP
- Abstract
Objective: This study aimed at exploring the attempters' perception of community social services included any barriers to seeking help and services., Method: The participants were patients with self-harming behavior aged 15 years or above. A set of guiding questions were designed to explore the general barriers and accessibility to community social services. A voice recording was made, which was later converted into a text transcript and then preceded for content analysis with co-occurrence and similarity matrix interpretation. Two males and nine females with a history of self-harm aged between 24 and 58 years were recruited for the interviews., Result: The participants had diverse experiences and backgrounds, and attitudes toward community social services. However, there was a shared perception of the need to enhance community social services. There were four main themes and 12 sub themes identified. The main theme included the service availability, service accessibility, affordability and acceptability. For details, participants were unaware of the available types of care/social services in the community, and were unaware about the nearby social services. They also suggested extending service hours and focused services should be offered to help people with different backgrounds and needs. Actually, those with experience of service utilization had both positive and negative perspectives and they gave suggestions for service delivery, mainly extending service hours and offering focused services such as for gambling control and financial planning. In view of interaction with service providers, counseling skills and trust were highly appreciated by the participants., Conclusion: The results identified common circumstances of falling into financial hardship (gambling) and social fragmentation (divorce, poor family relationships, and poor marital relationships), which also suggested to enhance services on center location, service arrangement, and skill of caregivers.
- Published
- 2018
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30. Long non-coding RNAs in hematological malignancies: translating basic techniques into diagnostic and therapeutic strategies.
- Author
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Wong NK, Huang CL, Islam R, and Yip SP
- Subjects
- Humans, Gene Expression Regulation, Neoplastic genetics, Hematologic Neoplasms genetics, RNA, Long Noncoding genetics
- Abstract
Recent studies have revealed that non-coding regions comprise the vast majority of the human genome and long non-coding RNAs (lncRNAs) are a diverse class of non-coding RNAs that has been implicated in a variety of biological processes. Abnormal expression of lncRNAs has also been linked to different human diseases including cancers, yet the regulatory mechanisms and functional effects of lncRNAs are still ambiguous, and the molecular details also need to be confirmed. Unlike protein-coding gene, it is much more challenging to unravel the roles of lncRNAs owing to their unique and complex features such as functional diversity and low conservation among species, which greatly hamper their experimental characterization. In this review, we summarize and discuss both conventional and advanced approaches for the identification and functional characterization of lncRNAs related to hematological malignancies. In particular, the utility and advancement of clustered regularly interspaced short palindromic repeats (CRISPR)-Cas system as gene-editing tools are envisioned to facilitate the molecular dissection of lncRNAs via different knock-in/out strategies. Besides experimental considerations specific to lncRNAs, the roles of lncRNAs in the pathogenesis and progression of leukemia are also highlighted in the review. We expect that these insights may ultimately lead to clinical applications including development of biomarkers and novel therapeutic approaches targeting lncRNAs.
- Published
- 2018
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31. Pure spatial and space-time clusters of self-harm in Kwai Tsing 2004 to 2012.
- Author
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Leung M, Chow CB, Ip PP, and Yip SP
- Subjects
- Adolescent, Adult, Aged, Female, Hong Kong epidemiology, Humans, Male, Middle Aged, Risk Assessment, Risk Factors, Socioeconomic Factors, Space-Time Clustering, Spatio-Temporal Analysis, Self-Injurious Behavior classification, Self-Injurious Behavior epidemiology
- Published
- 2018
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32. Characterization and Regulation of Gap Junctions in Porcine Ciliary Epithelium.
- Author
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Li SK, Shan SW, Li HL, Cheng AK, Pan F, Yip SP, Civan MM, To CH, and Do CW
- Subjects
- Animals, Aqueous Humor physiology, Biological Transport, Blotting, Western, Cells, Cultured, Connexins metabolism, Gene Knockdown Techniques, Protein Isoforms metabolism, RNA, Messenger genetics, RNA, Small Interfering genetics, Real-Time Polymerase Chain Reaction, Swine, Ciliary Body metabolism, Connexins genetics, Gap Junctions metabolism, Gene Expression Regulation physiology, Pigment Epithelium of Eye metabolism
- Abstract
Purpose: Gap junctions provide a conduit between the intracellular fluids of the pigmented (PE) and non-pigmented (NPE) ciliary epithelial cells, and are therefore critical in the secretion of the aqueous humor (AH). However, opinions differ concerning the connexin (Cx) composition of the gap junctions. Therefore, we aimed to characterize the expression of Cx in the porcine ciliary epithelium (CE), a favorable model for humans; and determine the contribution of the highest expressed Cx to AH secretion., Methods: Freshly-harvested porcine CE cells were used. The mRNA and protein expressions of gap junctions were assessed by reverse transcription polymerase chain reaction (RT-PCR) and Western blotting (WB), respectively. The relative gene expressions of various Cx were determined by quantitative PCR. The gap junction permeability of isolated PE-NPE cell couplets was evaluated by Lucifer Yellow dye transfer., Results: Using RT-PCR and WB, Cx43, Cx45, Cx47, Cx50, and Cx60 were present in porcine CE, with Cx43 being the most abundant isoform, having over 200-fold higher expression than other Cx. Cx43 was primarily localized in the PE-NPE interface and the basolateral membranes of PE cells. Knockdown of Cx43 by siRNA significantly reduced gene and protein expressions, resulting in reduction of transcellular fluid flow by 90%., Conclusions: Cx43 was found to be the major component of gap junctions in porcine CE. Consistent with results from a bovine model, our results support the important role of Cx43 in mediating AH secretion. This finding may shed light on the development of a novel ocular hypotensive agent.
- Published
- 2018
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33. Ablation of Bax and Bak protects skeletal muscle against pressure-induced injury.
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Tam BT, Yu AP, Tam EW, Monks DA, Wang XP, Pei XM, Koh SP, Sin TK, Law HKW, Ugwu FN, Supriya R, Yung BY, Yip SP, Wong SC, Chan LW, Lai CW, Ouyang P, and Siu PM
- Subjects
- Animals, Blotting, Western, Cell Death genetics, Cell Death physiology, Immunoprecipitation, Male, Mice, Mice, Knockout, bcl-2 Homologous Antagonist-Killer Protein genetics, bcl-2-Associated X Protein genetics, Muscle, Skeletal metabolism, Pressure adverse effects, bcl-2 Homologous Antagonist-Killer Protein metabolism, bcl-2-Associated X Protein metabolism
- Abstract
Pressure-induced injury (PI), such as a pressure ulcer, in patients with limited mobility is a healthcare issue worldwide. PI is an injury to skin and its underlying tissue such as skeletal muscle. Muscle compression, composed of mechanical deformation of muscle and external load, leads to localized ischemia and subsequent unloading reperfusion and, hence, a pressure ulcer in bed-bound patients. Although the gross factors involved in PI have been identified, little is known about the exact disease mechanism or its links to apoptosis, autophagy and inflammation. Here, we report that PI is mediated by intrinsic apoptosis and exacerbated by autophagy. Conditional ablation of Bax and Bak activates the Akt-mTOR pathway and Bnip3-mediated mitophagy and preserves mitochondrial contents in compressed muscle. Moreover, we find that the presence/absence of Bax and Bak alters the roles and functions of autophagy in PI. Our results suggest that manipulating apoptosis and autophagy are potential therapeutic targets for treatment and prevention of PI.
- Published
- 2018
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34. Computer-aided assessment of regional vascularity of thyroid nodules for prediction of malignancy.
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Baig FN, Lunenburg JTJV, Liu SYW, Yip SP, Law HKW, and Ying M
- Subjects
- Adult, Algorithms, Decision Making, Computer-Assisted, Diagnosis, Differential, Female, Humans, Male, Middle Aged, Neovascularization, Pathologic diagnostic imaging, Sensitivity and Specificity, Thyroid Neoplasms pathology, Ultrasonography methods, Ultrasonography, Doppler, Color methods, Thyroid Nodule blood supply, Thyroid Nodule diagnostic imaging, Thyroid Nodule pathology
- Abstract
Color Doppler vascular index (VI) was assessed alone and in combination with grey-scale ultrasound (GSU) in regionally subdivided thyroid nodules in diagnosing thyroid cancer. Color Doppler sonograms of 111 thyroid nodules were evaluated by a home-developed algorithm that performed "offsetting" (algorithm for changing the area of a region of interest, ROI, without distorting the ROI's contour) and assessed peripheral, central and overall VI of thyroid nodules. Results showed that the optimum offset for dividing peripheral and central regions of nodule was 22%. At the optimum offset, the mean VI of peripheral, central, and overall regions of malignant nodules were significantly higher than those of benign nodules (26.5 ± 16.2%, 21.7 ± 19.6%, 23.8 ± 4.6% v/s 18.2 ± 16.7%, 11.9 ± 15.1% and 16.6 ± 1.8% respectively, P < 0.05). The optimum cut-off of peripheral, central, and overall VI was 19.7%, 9.1% and 20.2% respectively. When compared to GSU alone, combination of VI assessment with GSU evaluation of thyroid nodules increased the diagnostic accuracy from 58.6% to 79.3% (P < 0.05). In conclusion, a novel algorithm for regional subdivision and quantification of thyroid nodular VI in ultrasound images was established, and the optimum offset and cut-off were derived. Assessment of intranodular VI in conjunction with GSU can increase the accuracy in ultrasound diagnosis of thyroid cancer.
- Published
- 2017
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35. Region-specific differential corneal and scleral mRNA expressions of MMP2, TIMP2, and TGFB2 in highly myopic-astigmatic chicks.
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Xi LY, Yip SP, Shan SW, Summers-Rada J, and Kee CS
- Subjects
- Animals, Chickens, Myopia genetics, Myopia physiopathology, Organ Specificity, RNA, Messenger metabolism, Cornea metabolism, Gene Expression Regulation, Matrix Metalloproteinase 2 genetics, RNA, Messenger genetics, Sclera metabolism, Tissue Inhibitor of Metalloproteinase-2 genetics, Transforming Growth Factor beta2 genetics
- Abstract
Myopia and astigmatism, two common refractive errors frequently co-exist, are affecting vision at all working distances in the affected populations worldwide. Eyeballs having these refractive errors are known to exhibit abnormal eye shape at the anterior and posterior eye segments, but whether the outer coats of these abnormal eyeballs, cornea anteriorly and sclera posteriorly, are regulated by region-specific molecular mechanism remains unclear. Here we presented the changes in mRNA expression levels of three genes (MMP2, TIMP2, and TGFB2), all known to participate in extracellular matrix organization, at five regions of the cornea and sclera in chickens developing high myopia and astigmatism induced by form deprivation. We found that, compared to normal chicks, the highly myopic-astigmatic chicks had significantly higher expression of all three genes in the superior sclera (Mann-Whitney tests, all p ≤ 0.05), as well as higher TIMP2 expression in the central cornea and nasal sclera (Mann-Whitney tests, both p ≤ 0.05). Strikingly, the superior scleral region stood out as showing the strongest and most widespread correlations between mRNA expression and biometry parameters including axial and astigmatic components (r = + 0.52~ + 0.85, all p < 0.05). These results imply that local molecular mechanism may manipulate the eye shape remodeling across the globe during refractive-error development.
- Published
- 2017
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36. Ultrasound Evaluation of Carotid Atherosclerosis in Post-Radiotherapy Nasopharyngeal Carcinoma Patients, Type 2 Diabetics, and Healthy Controls.
- Author
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Yuan C, Wu VW, Yip SP, Kwong DL, and Ying M
- Subjects
- Adult, Aged, Aged, 80 and over, Carotid Artery, Common diagnostic imaging, Carotid Artery, Common radiation effects, Carotid Intima-Media Thickness, Carotid Stenosis diagnostic imaging, Female, Humans, Image Interpretation, Computer-Assisted, Male, Middle Aged, Reference Values, Risk Factors, Vascular Stiffness physiology, Young Adult, Carotid Artery Diseases diagnostic imaging, Diabetes Mellitus, Type 2 diagnostic imaging, Nasopharyngeal Neoplasms radiotherapy, Radiation Injuries diagnostic imaging
- Abstract
Purpose To comprehensively evaluate and compare the degree of carotid atherosclerosis in patients treated with radiotherapy (RT) for nasopharyngeal carcinoma (NPC) and in patients with type 2 diabetes mellitus (DM), and using healthy subjects as controls. Materials and Methods The present study recruited 69 post-RT NPC patients without conventional cardiovascular risk factors, 70 type 2 diabetic patients without previous RT, and 76 healthy controls without conventional cardiovascular risk factors and previous RT. For each participant, 5 carotid atherosclerotic parameters, namely carotid intima-media thickness (CIMT), carotid arterial stiffness (CAS), presence of carotid plaque, carotid plaque score, and presence of ≥ 50 % carotid stenosis, were assessed using ultrasonography. The differences in these carotid atherosclerotic parameters between study groups were compared using ANCOVA or logistic regression after the adjustment for age and gender. Multiple comparisons were corrected using the Benjamini-Hochberg false discovery rate. Results Post-RT NPC patients and type 2 diabetics had a significantly higher CIMT, CAS and carotid plaque burden compared to the healthy subjects (corrected P-value, Pcor < 0.05). In addition, carotid atherosclerosis in post-RT NPC patients tended to be more severe with significantly higher CAS and carotid plaque burden than that in type 2 diabetics (Pcor < 0.05). Conclusion Neck RT for NPC is an independent risk factor of carotid atherosclerosis, and radiation induces more severe carotid atherosclerosis in post-RT NPC patients. Thus, assessment of carotid atherosclerosis using ultrasonography may be necessary for these patients and should be indicated in the routine follow-up of NPC., (© Georg Thieme Verlag KG Stuttgart · New York.)
- Published
- 2017
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37. Precipitation of PEG/Carboxyl-Modified Gold Nanoparticles with Magnesium Pyrophosphate: A New Platform for Real-Time Monitoring of Loop-Mediated Isothermal Amplification.
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Qin A, Fu LT, Wong JK, Chau LY, Yip SP, and Lee TM
- Subjects
- Gold, Metal Nanoparticles, Nucleic Acid Amplification Techniques, Polyethylene Glycols, Diphosphates chemistry, Magnesium Compounds chemistry
- Abstract
Gold nanoparticles have proven to be promising for decentralized nucleic acid testing by virtue of their simple visual readout and absorbance-based quantification. A major challenge toward their practical application is to achieve ultrasensitive detection without compromising simplicity. The conventional strategy of thermocycling amplification is unfavorable (because of both instrumentation and preparation of thermostable oligonucleotide-modified gold nanoparticle probes). Herein, on the basis of a previously unreported co-precipitation phenomenon between thiolated poly(ethylene glycol)/11-mercaptoundecanoic acid co-modified gold nanoparticles and magnesium pyrophosphate crystals (an isothermal DNA amplification reaction byproduct), a new ultrasensitive and simple DNA assay platform is developed. The binding mechanism underlying the co-precipitation phenomenon is found to be caused by the complexation of carboxyl and pyrophosphate with free magnesium ions. Remarkably, poly(ethylene glycol) does not hinder the binding and effectively stabilizes gold nanoparticles against magnesium ion-induced aggregation (without pyrophosphate). In fact, a similar phenomenon is observed in other poly(ethylene glycol)- and carboxyl-containing nanomaterials. When the gold nanoparticle probe is incorporated into a loop-mediated isothermal amplification reaction, it remains as a red dispersion for a negative sample (in the absence of a target DNA sequence) but appears as a red precipitate for a positive sample (in the presence of a target). This results in a first-of-its-kind gold nanoparticle-based DNA assay platform with isothermal amplification and real-time monitoring capabilities.
- Published
- 2017
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38. Pathway analysis of complex diseases for GWAS, extending to consider rare variants, multi-omics and interactions.
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Kao PY, Leung KH, Chan LW, Yip SP, and Yap MK
- Subjects
- Genome-Wide Association Study methods, Humans, Software, Polymorphism, Single Nucleotide genetics, Signal Transduction genetics
- Abstract
Background: Genome-wide association studies (GWAS) is a major method for studying the genetics of complex diseases. Finding all sequence variants to explain fully the aetiology of a disease is difficult because of their small effect sizes. To better explain disease mechanisms, pathway analysis is used to consolidate the effects of multiple variants, and hence increase the power of the study. While pathway analysis has previously been performed within GWAS only, it can now be extended to examining rare variants, other "-omics" and interaction data., Scope of Review: 1. Factors to consider in the choice of software for GWAS pathway analysis. 2. Examples of how pathway analysis is used to analyse rare variants, other "-omics" and interaction data., Major Conclusions: To choose appropriate software tools, factors for consideration include covariate compatibility, null hypothesis, one- or two-step analysis required, curation method of gene sets, size of pathways, and size of flanking regions to define gene boundaries. For rare variants, analysis performance depends on consistency between assumed and actual effect distribution of variants. Integration of other "-omics" data and interaction can better explain gene functions., General Significance: Pathway analysis methods will be more readily used for integration of multiple sources of data, and enable more accurate prediction of phenotypes., (Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2017
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39. Genetic Association Study of KCNQ5 Polymorphisms with High Myopia.
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Liao X, Yap MKH, Leung KH, Kao PYP, Liu LQ, and Yip SP
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- Adolescent, Adult, Alleles, Asian People, Female, Genotype, Haplotypes, Humans, Male, Middle Aged, Myopia pathology, Polymorphism, Single Nucleotide genetics, Young Adult, Genetic Association Studies, Genetic Predisposition to Disease, KCNQ Potassium Channels genetics, Myopia genetics
- Abstract
Identification of genetic variations related to high myopia may advance our knowledge of the etiopathogenesis of refractive error. This study investigated the role of potassium channel gene (KCNQ5) polymorphisms in high myopia. We performed a case-control study of 1563 unrelated Han Chinese subjects (809 cases of high myopia and 754 emmetropic controls). Five tag single-nucleotide polymorphisms (SNPs) of KCNQ5 were genotyped, and association testing with high myopia was conducted using logistic regression analysis adjusted for sex and age to give P
asym values, and multiple comparisons were corrected by permutation test to give Pemp values. All five noncoding SNPs were associated with high myopia. The SNP rs7744813, previously shown to be associated with refractive error and myopia in two GWAS, showed an odds ratio of 0.75 (95% CI 0.63-0.90; Pemp = 0.0058) for the minor allele. The top SNP rs9342979 showed an odds ratio of 0.75 (95% CI 0.64-0.89; Pemp = 0.0045) for the minor allele. Both SNPs are located within enhancer histone marks and DNase-hypersensitive sites. Our data support the involvement of KCNQ5 gene polymorphisms in the genetic susceptibility to high myopia and further exploration of KCNQ5 as a risk factor for high myopia.- Published
- 2017
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40. Platinum nanoparticles on reduced graphene oxide as peroxidase mimetics for the colorimetric detection of specific DNA sequence.
- Author
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Chau LY, He Q, Qin A, Yip SP, and Lee TMH
- Abstract
In this work, we developed a simple and sensitive colorimetric detection platform for specific DNA sequences by using peroxidase mimetics of platinum nanoparticles supported on reduced graphene oxide. This nanocomposite possessed the combined advantages of platinum nanoparticles (superior peroxidase-like activity) and reduced graphene oxide (π-stacking interaction with single-stranded but not double-stranded DNA). The catalytic activity was strongly dependent on the chloroplatinic acid-to-graphene oxide mass ratio during the synthesis step, with an optimum ratio of 7 : 1. Unlike natural peroxidase, the nanocomposite had excellent stability over wide ranges of temperature (4-90 °C) and pH (1-13). For DNA detection, the nanocomposite had higher affinity for the single-stranded probe (in the absence of target) than the probe-target duplex. The probe-bound nanocomposite was stabilized against salt-induced aggregation and thus upon the addition of 3,3',5,5'-tetramethylbenzidine and hydrogen peroxide to the supernatant, an intense blue color was generated. The linear range and limit of detection of this assay platform were 0.5-10 nM and 0.4 nM, respectively. Moreover, this platform featured high specificity that 3-base-mismatched sequence could be distinguished with the naked eye and 1-base-mismatched sequence with absorbance measurement. Furthermore, the applicability for real sample detection was demonstrated by polymerase chain reaction product analysis. Taken together, this new platform is well suited for point-of-care and on-site nucleic acid testing.
- Published
- 2016
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41. Acute Treatment of Resveratrol Alleviates Doxorubicin-Induced Myotoxicity in Aged Skeletal Muscle Through SIRT1-Dependent Mechanisms.
- Author
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Sin TK, Tam BT, Yu AP, Yip SP, Yung BY, Chan LW, Wong CS, Rudd JA, and Siu PM
- Subjects
- Age Factors, Animals, Apoptosis drug effects, Cardiotoxicity etiology, Caspase 3 metabolism, Enzyme-Linked Immunosorbent Assay, Male, Mice, Muscle, Skeletal metabolism, Oxidative Stress drug effects, Proteasome Endopeptidase Complex metabolism, Pyruvate Dehydrogenase Complex metabolism, Random Allocation, Resveratrol, Signal Transduction drug effects, Staining and Labeling, Cardiotoxicity prevention & control, Doxorubicin toxicity, Muscle, Skeletal drug effects, Sirtuin 1 drug effects, Sirtuin 1 metabolism, Stilbenes pharmacology
- Abstract
Study of the exacerbating effects of chemotherapeutics, such as doxorubicin, on the impairment of insulin metabolic signaling in aged skeletal muscle is very limited. Here, we tested the hypothesis that activation of sirtuin 1 deacetylase activity by resveratrol would prevent the disruption of insulin signaling and augmentation of catabolic markers induced by doxorubicin in aged skeletal muscle. Two- and 10-month-old senescence-accelerated mice (prone 8) were randomized to receive saline, doxorubicin, doxorubicin and resveratrol, or a combination of doxorubicin, resveratrol, and sirtinol or EX527. Doxorubicin reduced the sirtuin 1 activity without affecting the phosphorylation levels of IRS1(Ser307), mTOR(Ser2481), Akt(Thr308/Ser473), membranous glucose transporter 4, protein abundance of PDK4, and enzymatic activity of pyruvate dehydrogenase in aged muscles. Intriguingly, resveratrol attenuated the doxorubicin-induced elevations of apoptotic and catabolic markers measured as Bax, caspase 3 activity, apoptotic DNA fragmentation, MuRF-1, ubiquitinated proteins, and proteasomal activity in aged muscles, whereas these beneficial effects were abolished on inhibition of sirtuin 1 by sirtinol or EX527. Markers of insulin signaling were not affected by doxorubicin or resveratrol in the senescent skeletal muscle. Nevertheless, the antiapoptotic and anticatabolic effects of resveratrol in aged skeletal muscle treated with doxorubicin were mediated in a sirtuin 1-dependent signaling manner., (© The Author 2015. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
- Published
- 2016
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42. Meta-analysis of gene-environment-wide association scans accounting for education level identifies additional loci for refractive error.
- Author
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Fan Q, Verhoeven VJ, Wojciechowski R, Barathi VA, Hysi PG, Guggenheim JA, Höhn R, Vitart V, Khawaja AP, Yamashiro K, Hosseini SM, Lehtimäki T, Lu Y, Haller T, Xie J, Delcourt C, Pirastu M, Wedenoja J, Gharahkhani P, Venturini C, Miyake M, Hewitt AW, Guo X, Mazur J, Huffman JE, Williams KM, Polasek O, Campbell H, Rudan I, Vatavuk Z, Wilson JF, Joshi PK, McMahon G, St Pourcain B, Evans DM, Simpson CL, Schwantes-An TH, Igo RP, Mirshahi A, Cougnard-Gregoire A, Bellenguez C, Blettner M, Raitakari O, Kähönen M, Seppala I, Zeller T, Meitinger T, Ried JS, Gieger C, Portas L, van Leeuwen EM, Amin N, Uitterlinden AG, Rivadeneira F, Hofman A, Vingerling JR, Wang YX, Wang X, Tai-Hui Boh E, Ikram MK, Sabanayagam C, Gupta P, Tan V, Zhou L, Ho CE, Lim W, Beuerman RW, Siantar R, Tai ES, Vithana E, Mihailov E, Khor CC, Hayward C, Luben RN, Foster PJ, Klein BE, Klein R, Wong HS, Mitchell P, Metspalu A, Aung T, Young TL, He M, Pärssinen O, van Duijn CM, Jin Wang J, Williams C, Jonas JB, Teo YY, Mackey DA, Oexle K, Yoshimura N, Paterson AD, Pfeiffer N, Wong TY, Baird PN, Stambolian D, Wilson JE, Cheng CY, Hammond CJ, Klaver CC, Saw SM, Rahi JS, Korobelnik JF, Kemp JP, Timpson NJ, Smith GD, Craig JE, Burdon KP, Fogarty RD, Iyengar SK, Chew E, Janmahasatian S, Martin NG, MacGregor S, Xu L, Schache M, Nangia V, Panda-Jonas S, Wright AF, Fondran JR, Lass JH, Feng S, Zhao JH, Khaw KT, Wareham NJ, Rantanen T, Kaprio J, Pang CP, Chen LJ, Tam PO, Jhanji V, Young AL, Döring A, Raffel LJ, Cotch MF, Li X, Yip SP, Yap MK, Biino G, Vaccargiu S, Fossarello M, Fleck B, Yazar S, Tideman JW, Tedja M, Deangelis MM, Morrison M, Farrer L, Zhou X, Chen W, Mizuki N, Meguro A, and Mäkelä KM
- Subjects
- Asian People genetics, Gene Expression Profiling, Humans, Polymorphism, Single Nucleotide genetics, White People genetics, Educational Status, Environment, Genetic Loci, Genetic Predisposition to Disease, Genome-Wide Association Study, Refractive Errors genetics
- Abstract
Myopia is the most common human eye disorder and it results from complex genetic and environmental causes. The rapidly increasing prevalence of myopia poses a major public health challenge. Here, the CREAM consortium performs a joint meta-analysis to test single-nucleotide polymorphism (SNP) main effects and SNP × education interaction effects on refractive error in 40,036 adults from 25 studies of European ancestry and 10,315 adults from 9 studies of Asian ancestry. In European ancestry individuals, we identify six novel loci (FAM150B-ACP1, LINC00340, FBN1, DIS3L-MAP2K1, ARID2-SNAT1 and SLC14A2) associated with refractive error. In Asian populations, three genome-wide significant loci AREG, GABRR1 and PDE10A also exhibit strong interactions with education (P<8.5 × 10(-5)), whereas the interactions are less evident in Europeans. The discovery of these loci represents an important advance in understanding how gene and environment interactions contribute to the heterogeneity of myopia.
- Published
- 2016
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43. Correction: Multivariate analysis of electrophysiological diversity of Xenopus visual neurons during development and plasticity.
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Ciarleglio CM, Khakhalin AS, Wang AF, Constantino AC, Yip SP, and Aizenman CD
- Published
- 2016
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44. Unacylated ghrelin restores insulin and autophagic signaling in skeletal muscle of diabetic mice.
- Author
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Tam BT, Pei XM, Yung BY, Yip SP, Chan LW, Wong CS, and Siu PM
- Subjects
- Acetylation, Animals, Diabetes Mellitus, Type 2 genetics, Diabetes Mellitus, Type 2 metabolism, Ghrelin therapeutic use, Glucose Transporter Type 4 metabolism, Hypoglycemic Agents therapeutic use, Insulin Receptor Substrate Proteins metabolism, Male, Mice, Muscle, Skeletal drug effects, Phosphorylation, Protein Processing, Post-Translational, Proto-Oncogene Proteins c-akt metabolism, Receptors, Leptin genetics, TOR Serine-Threonine Kinases metabolism, Autophagy, Diabetes Mellitus, Type 2 drug therapy, Ghrelin pharmacology, Hypoglycemic Agents pharmacology, Insulin blood, Muscle, Skeletal metabolism, Signal Transduction
- Abstract
Impairment of insulin signaling in skeletal muscle detrimentally affects insulin-stimulated disposal of glucose. Restoration of insulin signaling in skeletal muscle is important as muscle is one of the major sites for disposal of blood glucose. Recently, unacylated ghrelin (UnAG) has received attention in diabetic research due to its favorable actions on improving glucose tolerance, glycemic control, and insulin sensitivity. The investigation of UnAG has entered phase Ib clinical trial in type 2 diabetes and phase II clinical trial in hyperphagia in Prader-Willi syndrome. Nonetheless, the precise mechanisms responsible for the anti-diabetic actions of UnAG remain incompletely understood. In this study, we examined the effects of UnAG on restoring the impaired insulin signaling in skeletal muscle of db/db diabetic mice. Our results demonstrated that UnAG effectively restored the impaired insulin signaling in diabetic muscle. UnAG decreased insulin receptor substrate (IRS) phosphorylation, increased protein kinase B (Akt) phosphorylation, and, hence, suppressed mTOR signaling. Consequently, UnAG enhanced Glut4 localization and increased PDH activity in the diabetic skeletal muscle. Intriguingly, our data indicated that UnAG normalized the suppressed autophagic signaling in diabetic muscle. In conclusion, our findings illustrated that UnAG restored the impaired insulin and autophagic signaling in skeletal muscle of diabetic mice, which are valuable to understand the underlying mechanisms of the anti-diabetic action of UnAG at peripheral skeletal muscle level.
- Published
- 2015
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45. Effects of long-term resveratrol-induced SIRT1 activation on insulin and apoptotic signalling in aged skeletal muscle.
- Author
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Sin TK, Yu AP, Yung BY, Yip SP, Chan LW, Wong CS, Rudd JA, and Siu PM
- Subjects
- Aging, Animals, Forkhead Box Protein O1 metabolism, Male, Mice, Motor Activity drug effects, Muscle Proteins metabolism, Muscle, Skeletal growth & development, Muscle, Skeletal metabolism, Oxidative Stress drug effects, Physical Endurance drug effects, Pyruvate Dehydrogenase Complex metabolism, Resveratrol, Sirtuin 1 drug effects, Anti-Inflammatory Agents, Non-Steroidal pharmacology, Apoptosis drug effects, Insulin metabolism, Muscle, Skeletal drug effects, Signal Transduction drug effects, Sirtuin 1 metabolism, Stilbenes pharmacology
- Abstract
Aims: Activation of Foxo1 is known to promote apoptosis and disturbances to insulin signalling. However, their modulating roles in aged skeletal muscle are not clear. The present study tested the hypothesis that long-term (i.e. 8 month) resveratrol supplementation would improve physical traits including exercise capacity and basal voluntary activity of aged mice and modulate insulin/apoptotic signalling in aged skeletal muscle. This study also examined whether these resveratrol-associated alterations would involve orchestration of the SIRT1-Foxo1 signalling axis., Methods: Two-month-old SAMP8 mice were randomly assigned to young, aged and aged with resveratrol treatment (AR) groups. The AR mice were supplemented with 4.9 mg(-1) kg(-1) day(-1) resveratrol for 8 months. All animals were subject to endurance capacity test and voluntary motor behaviour assessment. The lateral gastrocnemius muscle tissues were harvested for further analyses., Results: Long-term resveratrol treatment significantly alleviated the age-associated reductions in exercise capacity and voluntary motor behaviour. The protein content, but not the deacetylase activity of SIRT1 was increased with concomitant elevations of p300 acetylase and acetylation of Foxo1 in aged muscle. The aged muscle also manifested signs of impaired insulin signalling including attenuated phosphorylation of Akt, activity of pyruvate dehydrogenase and membrane trafficking of GLUT4 and elevated levels of phosphorylated IRS1 and iNOS and apoptotic activation measured as Bim, p53 and apoptotic DNA fragmentation. Intriguingly, all these age-related adverse changes were mitigated with the activation of SIRT1 deacetylase activity after long-term resveratrol treatment., Conclusions: These data suggest that modulation of the SIRT1-Foxo1 axis by long-term resveratrol treatment enhances physical traits and alleviates the unfavourable changes in insulin and apoptotic signalling in aged muscle.
- Published
- 2015
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46. Multivariate analysis of electrophysiological diversity of Xenopus visual neurons during development and plasticity.
- Author
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Ciarleglio CM, Khakhalin AS, Wang AF, Constantino AC, Yip SP, and Aizenman CD
- Subjects
- Action Potentials, Animals, Photic Stimulation, Electrophysiological Phenomena, Mesencephalon embryology, Neuronal Plasticity, Neurons physiology, Visual Pathways cytology, Visual Pathways embryology, Xenopus embryology
- Abstract
Biophysical properties of neurons become increasingly diverse over development, but mechanisms underlying and constraining this diversity are not fully understood. Here we investigate electrophysiological characteristics of Xenopus tadpole midbrain neurons across development and during homeostatic plasticity induced by patterned visual stimulation. We show that in development tectal neuron properties not only change on average, but also become increasingly diverse. After sensory stimulation, both electrophysiological diversity and functional differentiation of cells are reduced. At the same time, the amount of cross-correlations between cell properties increase after patterned stimulation as a result of homeostatic plasticity. We show that tectal neurons with similar spiking profiles often have strikingly different electrophysiological properties, and demonstrate that changes in intrinsic excitability during development and in response to sensory stimulation are mediated by different underlying mechanisms. Overall, this analysis and the accompanying dataset provide a unique framework for further studies of network maturation in Xenopus tadpoles.
- Published
- 2015
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47. SIRT1-dependent myoprotective effects of resveratrol on muscle injury induced by compression.
- Author
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Sin TK, Yung BY, Yip SP, Chan LW, Wong CS, Tam EW, and Siu PM
- Abstract
Our current understanding on the molecular mechanisms by which sustained compression induces skeletal muscle injury is very limited. This study aimed to test the hypothesis that activation of SIRT1 by the natural antioxidant resveratrol could deactivate apoptotic and catabolic signaling in skeletal muscle exposed to moderate compression. Two cycles of 6-h constant pressure at 100 mmHg was applied to the tibialis region of right, but not left hindlimbs of Sprague Dawley rats pre-treated with DMSO (vehicle control) or resveratrol with/without sirtinol. Skeletal muscle tissues lying underneath and spatially corresponding to the compressed sites were collected for analyses. Resveratrol prevented the compression-induced manifestations of pathohistological damages including elevations of the number of interstitial nuclei and area of interstitial space and ameliorated oxidative damages measured as 4-hydroxy-2-nonenal (4HNE) and nitrotyrosine in skeletal muscle. In parallel, resveratrol augmented the expression level and activity of SIRT1 and phosphorylation levels of Foxo3a and Akt while suppressed the increases in protein abundances of p53, Bax, MAFbx, and ubiquitin, enzymatic activities of caspase 3 and 20S proteasome, and apoptotic DNA fragmentation in the compressed muscle. These favorable myoprotective effects of resveratrol were diminished upon pharmacological blockade of SIRT1 by using sirtinol. These novel data support the hypothesis that the anti-apoptotic and anti-catabolic effects of resveratrol on compression injury in skeletal muscle required the action of SIRT1.
- Published
- 2015
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48. Autophagic Adaptations to Long-term Habitual Exercise in Cardiac Muscle.
- Author
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Tam BT, Pei XM, Yung BY, Yip SP, Chan LW, Wong CS, and Siu PM
- Subjects
- Animals, Female, HSP72 Heat-Shock Proteins metabolism, Microtubule-Associated Proteins metabolism, Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha, Phosphorylation physiology, Rats, Rats, Sprague-Dawley, Time Factors, Transcription Factors metabolism, Adaptation, Physiological physiology, Autophagy physiology, Myocardium metabolism, Physical Conditioning, Animal physiology
- Abstract
Autophagy has been shown to be responsive to physical exercise. However, the effects of prolonged habitual exercise on autophagy in cardiac muscle remain unknown. The present study aimed to examine whether long-term habitual exercise alters the basal autophagic signalling in cardiac muscle. Female Sprague-Dawley rats aged 2 months were randomly assigned to control and exercise groups. Animals in exercise group were kept in cages with free access exercise wheels to perform habitual exercise for 5 months. Animals in the control group were placed in cages without exercise wheels. Ventricular muscle tissues were harvested for analysis after 5 months. Phosphorylation statuses of upstream autophagic regulatory proteins and protein expressions of downstream autophagic facts remained unchanged in the cardiac muscle of exercise animals when compared to control animals. Intriguingly, the protein abundance of microtubule-associated protein-1 light chain -3 II (LC3-II), heat shock protein 72 (HSP72) and peroxisome proliferator-activated receptor-gamma coactivator (PGC-1α) were significantly increased in cardiac muscle of exercise rats relative to control rats. 5 months of habitual exercise causes the adaptive increase in LC3-II reserve without altering autophagic flux, which probably contributes to the elevation of cellular autophagic capacity and efficiency of cardiac muscle., (© Georg Thieme Verlag KG Stuttgart · New York.)
- Published
- 2015
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49. Autophagic adaptation is associated with exercise-induced fibre-type shifting in skeletal muscle.
- Author
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Tam BT, Pei XM, Yu AP, Sin TK, Leung KK, Au KK, Chong JT, Yung BY, Yip SP, Chan LW, Wong CS, and Siu PM
- Subjects
- Acclimatization physiology, Animals, Female, Muscle Fibers, Skeletal metabolism, Rats, Sprague-Dawley, Adaptation, Physiological physiology, Autophagy physiology, Muscle Fibers, Skeletal pathology, Muscle, Skeletal physiology, Physical Conditioning, Animal physiology, Running physiology
- Abstract
Aim: Acute exercise is known to activate autophagy in skeletal muscle. However, little is known about how basal autophagy in skeletal muscle adapts to chronic exercise. In the current study we aim to, firstly, examine whether long-term habitual exercise alters the basal autophagic signalling in plantaris muscle and, secondly, examine the association between autophagy and fibre-type shifting., Methods: Adult female Sprague-Dawley rats aged 2 months were randomly assigned to control and exercise groups. Animals in exercise group were kept in cages equipped with free access running wheels to perform habitual exercise for 5 months. Animals in the control group were caged in the absence of running wheels. Animals were sacrificed after the 5-month experimental period. Plantaris muscle tissues were harvested for analysis., Results: We showed that long-term habitual exercise enhanced basal autophagy, but without altering expressions of autophagy proteins in plantaris muscle. Interestingly, sirtuin protein, a possible regulator of autophagy, was upregulated in plantaris muscle. Furthermore, we suspected that different types of muscle fibre adapted to chronic exercise in different ways. Long-term habitual exercise resulted in fibre-type shifting from type IIX to IIA in both gastrocnemius muscle and plantaris muscle. Intriguingly, our analysis demonstrated that LC3-II protein abundance is positively correlated with the proportion of type IIA fibre whereas it was negatively correlated with the proportion of type IIX fibre in plantaris muscle. PGC-1α protein abundance was positively associated with the proportion of type IIA fibre and LC3-II in plantaris muscle., Conclusion: These results suggest that basal autophagy is enhanced in plantaris muscle after long-term habitual exercise and associated with fibre-type shifting., (© 2015 Scandinavian Physiological Society. Published by John Wiley & Sons Ltd.)
- Published
- 2015
- Full Text
- View/download PDF
50. Resveratrol protects against doxorubicin-induced cardiotoxicity in aged hearts through the SIRT1-USP7 axis.
- Author
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Sin TK, Tam BT, Yung BY, Yip SP, Chan LW, Wong CS, Ying M, Rudd JA, and Siu PM
- Subjects
- Animals, Apoptosis drug effects, Cardiotoxicity etiology, Heart, Mice, Myocytes, Cardiac metabolism, Oxidative Stress drug effects, Resveratrol, Signal Transduction drug effects, Ubiquitin-Specific Peptidase 7, Antioxidants pharmacology, Cardiotoxicity prevention & control, Doxorubicin pharmacology, Sirtuin 1 metabolism, Stilbenes pharmacology, Ubiquitin-Specific Proteases metabolism
- Abstract
Key Points: Doxorubicin induced functional deteriorations and elevations of USP7-related apoptotic/catabolic signalling in the senescent heart Resveratrol protects against doxorubicin-induced alterations through the restoration of SIRT1 deacetylase activity, Abstract: A compromised cardiac function is often seen in elderly cancer patients receiving doxorubicin therapy. The present study tested the hypothesis that acute intervention with resveratrol, a natural anti-oxidant found in grapes and red wine, reduces the cardiotoxicity of doxorubicin through restoration of sirtuin 1 (SIRT1) deacetylase activity, and attenuation of the catabolic/apoptotic pathways orchestrated by USP7, a p53 deubiquitinating protein, using young (aged 2 months) and old (aged 10 months) senescence-accelerated mice prone 8 (SAMP8). Animals were randomised to receive saline, doxorubicin, and doxorubicin in combination with resveratrol, in the presence or absence of SIRT1 inhibitors, sirtinol or EX527. Resveratrol alone, but not in combination with either of the SIRT1 inhibitors, suppressed the doxorubicin-induced impairment of cardiac systolic function in aged animals. Doxorubicin reduced SIRT1 deacetylase activity, and elevated proteasomal activity and USP7; it also increased the protein level of p300 and ubiquitinated proteins in hearts from aged SAMP8. These doxorubicin-induced alterations were prevented by resveratrol, whereas the protective action of resveratrol was antagonised by sirtinol and EX527. In young SAMP8 hearts, resveratrol attenuated the doxorubicin-induced increases in acetylation of Foxo1 and transactivation of MuRF-1, whereas these mitigations were not found after treatment with SIRT1 inhibitors. However, the protein contents of acetylated Foxo1 and MuRF-1 were not affected by any of the drugs studied in aged SAMP8 hearts. Resveratrol also ameliorated the augmentation of pro-apoptotic markers including p53, Bax, caspase 3 activity and apoptotic DNA fragmentation induced by doxorubicin in hearts from aged animals, whereas these reductions were diminished by combined treatment with SIRT1 inhibitors. These data demonstrate that resveratrol ameliorates doxorubicin-induced cardiotoxicity in aged hearts through the restoration of SIRT1 activity to attenuate USP7-related catabolic/pro-apoptotic signalling., (© 2015 The Authors. The Journal of Physiology © 2015 The Physiological Society.)
- Published
- 2015
- Full Text
- View/download PDF
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