77 results on '"Raymond Wan"'
Search Results
2. Development of genome-wide polygenic risk scores for lipid traits and clinical applications for dyslipidemia, subclinical atherosclerosis, and diabetes cardiovascular complications among East Asians
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Claudia H. T. Tam, Cadmon K. P. Lim, Andrea O. Y. Luk, Alex C. W. Ng, Heung-man Lee, Guozhi Jiang, Eric S. H. Lau, Baoqi Fan, Raymond Wan, Alice P. S. Kong, Wing-hung Tam, Risa Ozaki, Elaine Y. K. Chow, Ka-fai Lee, Shing-chung Siu, Grace Hui, Chiu-chi Tsang, Kam-piu Lau, Jenny Y. Y. Leung, Man-wo Tsang, Grace Kam, Ip-tim Lau, June K. Y. Li, Vincent T. F. Yeung, Emmy Lau, Stanley Lo, Samuel Fung, Yuk-lun Cheng, Chun-chung Chow, Miao Hu, Weichuan Yu, Stephen K. W. Tsui, Yu Huang, Huiyao Lan, Cheuk-chun Szeto, Nelson L. S. Tang, Maggie C. Y. Ng, Wing-yee So, Brian Tomlinson, Juliana C. N. Chan, Ronald C. W. Ma, The Hong Kong Diabetes Register TRS Study Group, and The Hong Kong Diabetes Biobank Study Group
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Polygenic risk scores ,Lipid traits ,Subclinical atherosclerosis ,Diabetes cardiovascular complications ,East Asians ,Medicine ,Genetics ,QH426-470 - Abstract
Abstract Background The clinical utility of personal genomic information in identifying individuals at increased risks for dyslipidemia and cardiovascular diseases remains unclear. Methods We used data from Biobank Japan (n = 70,657–128,305) and developed novel East Asian-specific genome-wide polygenic risk scores (PRSs) for four lipid traits. We validated (n = 4271) and subsequently tested associations of these scores with 3-year lipid changes in adolescents (n = 620), carotid intima-media thickness (cIMT) in adult women (n = 781), dyslipidemia (n = 7723), and coronary heart disease (CHD) (n = 2374 cases and 6246 controls) in type 2 diabetes (T2D) patients. Results Our PRSs aggregating 84–549 genetic variants (0.251
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- 2021
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3. Chlamydia trachomatis Strain Types Have Diversified Regionally and Globally with Evidence for Recombination across Geographic Divides
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Vitaly Smelov, Alison Vrbanac, Eleanne F. van Ess, Marlies P. Noz, Raymond Wan, Carina Eklund, Tyler Morgan, Lydia A. Shrier, Blake Sanders, Joakim Dillner, Henry J. C. de Vries, Servaas A. Morre, and Deborah Dean
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Chlamydia trachomatis ,MLST ,recombination ,global diversification ,allele mixing ,reassortment ,Microbiology ,QR1-502 - Abstract
Chlamydia trachomatis (Ct) is the leading cause of bacterial sexually transmitted diseases worldwide. The Ct Multi Locus Sequence Typing (MLST) scheme is effective in differentiating strain types (ST), deciphering transmission patterns and treatment failure, and identifying recombinant strains. Here, we analyzed 323 reference and clinical samples, including 58 samples from Russia, an area that has not previously been represented in Ct typing schemes, to expand our knowledge of the global diversification of Ct STs. The 323 samples resolved into 84 unique STs, a 3.23 higher typing resolution compared to the gold standard single locus ompA genotyping. Our MLST scheme showed a high discriminatory index, D, of 0.98 (95% CI 0.97–0.99) confirming the validity of this method for typing. Phylogenetic analyses revealed distinct branches for the phenotypic diseases of lymphogranuloma venereum, urethritis and cervicitis, and a sub-branch for ocular trachoma. Consistent with these findings, single nucleotide polymorphisms were identified that significantly correlated with each phenotype. While the overall number of unique STs per region was comparable across geographies, the number of STs was greater for Russia with a significantly higher ST/sample ratio of 0.45 (95% CI: 0.35–0.53) compared to Europe or the Americas (p < 0.009), which may reflect a higher level of sexual mixing with the introduction of STs from other regions and/or reassortment of alleles. Four STs were found to be significantly associated with a particular geographic region. ST23 [p = 0.032 (95% CI: 1–23)], ST34 [p = 0.019 (95% CI: 1.1–25)]; and ST19 [p = 0.001 (95% CI: 1.7–34.7)] were significantly associated with Netherlands compared to Russia or the Americas, while ST 30 [p = 0.031 (95% CI: 1.1–17.8)] was significantly associated with the Americas. ST19 was significantly associated with Netherlands and Russia compared with the Americans [p = 0.001 (95% CI: 1.7–34.7) and p = 0.006 (95% CI: 1.5–34.6), respectively]. Additionally, recombinant strains were ubiquitous in the data set [106 (32.8%)], although Europe had a significantly higher number than Russia or the Americas (p < 0.04), the majority of which were from Amsterdam [43 (87.8%) of 49)]. The higher number of recombinants in Europe indicates selective pressure and/or adaptive diversification that will require additional studies to elucidate.
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- 2017
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4. Novel Chlamydia trachomatis Strains in Heterosexual Sex Partners, Indianapolis, Indiana, USA
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Byron E. Batteiger, Raymond Wan, James A. Williams, Linda He, Arissa Ma, J. Dennis Fortenberry, and Deborah Dean
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Chlamydia trachomatis ,MLST ,partner tracing ,recombinant strains ,bacteria ,STIs ,Medicine ,Infectious and parasitic diseases ,RC109-216 - Abstract
Chlamydia trachomatis causes a high number of sexually transmitted infections worldwide, but reproducible and precise strain typing to link partners is lacking. We evaluated multilocus sequence typing (MLST) for this purpose by detecting sequence types (STs) concordant for the ompA genotype, a single-locus typing standard. We tested samples collected during April 2000–October 2003 from members of established heterosexual partnerships (dyads) in the Indianapolis, Indiana, USA, area who self-reported being coital partners within the previous 30 days. C. trachomatis DNA from 28 dyads was tested by MLST; sequences were aligned and analyzed for ST and phylogenetic relationships. MLST detected 9 C. trachomatis STs, 4 unique to Indianapolis; STs were identical within each dyad. Thirteen unique strains were identified; 9 (32%) dyads harbored novel recombinant strains that phylogenetically clustered with strains comprising the recombinants. The high rate of novel C. trachomatis recombinants identified supports the use of MLST for transmission and strain diversity studies among at-risk populations.
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- 2014
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5. Predicting Phenotype and Emerging Strains among Chlamydia trachomatis Infections
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Deborah Dean, William J. Bruno, Raymond Wan, João P. Gomes, Stéphanie Devignot, Tigist Mehari, Henry J.C. de Vries, Servaas A. Morré, Garry Myers, Timothy D. Read, and Brian G. Spratt
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Chlamydia trachomatis ,single nucleotide polymorphisms ,bacterial sequence typing ,sexually transmitted infections ,trachoma ,bacteria ,Medicine ,Infectious and parasitic diseases ,RC109-216 - Abstract
Chlamydia trachomatis is a global cause of blinding trachoma and sexually transmitted infections (STIs). We used comparative genomics of the family Chlamydiaceae to select conserved housekeeping genes for C. trachomatis multilocus sequencing, characterizing 19 reference and 68 clinical isolates from 6 continental/subcontinental regions. There were 44 sequence types (ST). Identical STs for STI isolates were recovered from different regions, whereas STs for trachoma isolates were restricted by continent. Twenty-nine of 52 alleles had nonuniform distributions of frequencies across regions (p
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- 2009
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6. Hypervirulent Chlamydia trachomatis Clinical Strain Is a Recombinant between Lymphogranuloma Venereum (L2) and D Lineages
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Naraporn Somboonna, Raymond Wan, David M. Ojcius, Matthew A. Pettengill, Sandeep J. Joseph, Alexander Chang, Ray Hsu, Timothy D. Read, and Deborah Dean
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Microbiology ,QR1-502 - Abstract
ABSTRACT Chlamydia trachomatis is an obligate intracellular bacterium that causes a diversity of severe and debilitating diseases worldwide. Sporadic and ongoing outbreaks of lymphogranuloma venereum (LGV) strains among men who have sex with men (MSM) support the need for research on virulence factors associated with these organisms. Previous analyses have been limited to single genes or genomes of laboratory-adapted reference strain L2/434 and outbreak strain L2b/UCH-1/proctitis. We characterized an unusual LGV strain, termed L2c, isolated from an MSM with severe hemorrhagic proctitis. L2c developed nonfusing, grape-like inclusions and a cytotoxic phenotype in culture, unlike the LGV strains described to date. Deep genome sequencing revealed that L2c was a recombinant of L2 and D strains with conserved clustered regions of genetic exchange, including a 78-kb region and a partial, yet functional, toxin gene that was lost with prolonged culture. Indels (insertions/deletions) were discovered in an ftsK gene promoter and in the tarp and hctB genes, which encode key proteins involved in replication, inclusion formation, and histone H1-like protein activity, respectively. Analyses suggest that these indels affect gene and/or protein function, supporting the in vitro and disease phenotypes. While recombination has been known to occur for C. trachomatis based on gene sequence analyses, we provide the first whole-genome evidence for recombination between a virulent, invasive LGV strain and a noninvasive common urogenital strain. Given the lack of a genetic system for producing stable C. trachomatis mutants, identifying naturally occurring recombinants can clarify gene function and provide opportunities for discovering avenues for genomic manipulation. IMPORTANCE Lymphogranuloma venereum (LGV) is a prevalent and debilitating sexually transmitted disease in developing countries, although there are significant ongoing outbreaks in Australia, Europe, and the United States among men who have sex with men (MSM). Relatively little is known about LGV virulence factors, and only two LGV genomes have been sequenced to date. We isolated an LGV strain from an MSM with severe hemorrhagic proctitis that was morphologically unique in tissue culture compared with other LGV strains. Bioinformatic and statistical analyses identified the strain as a recombinant of L2 and D strains with highly conserved clustered regions of genetic exchange. The unique culture morphology and, more importantly, disease phenotype could be traced to the genes involved in recombination. The findings have implications for bacterial species evolution and, in the case of ongoing LGV outbreaks, suggest that recombination is a mechanism for strain emergence that results in significant disease pathology.
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- 2011
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7. OMBlast: alignment tool for optical mapping using a seed-and-extend approach.
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Alden King-Yung Leung, Tsz-Piu Kwok, Raymond Wan 0001, Ming Xiao, Pui-Yan Kwok, Kevin Y. Yip, and Ting-Fung Chan
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- 2017
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8. Sorting next generation sequencing data improves compression effectiveness.
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Raymond Wan 0001 and Kiyoshi Asai
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- 2010
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9. Efficient Probabilistic Latent Semantic Analysis through Parallelization.
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Raymond Wan 0001, Vo Ngoc Anh, and Hiroshi Mamitsuka
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- 2009
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10. Term Impacts as Normalized Term Frequencies for BM25 Similarity Scoring.
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Vo Ngoc Anh, Raymond Wan 0001, and Alistair Moffat
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- 2008
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11. A Brief Guide to Legal Issues for Data-miners.
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Aaron Lai, Thomas Ho, and Raymond Wan 0002
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- 2008
12. Applying Gaussian Distribution-Dependent Criteria to Decision Trees for High-Dimensional Microarray Data.
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Raymond Wan 0001, Ichigaku Takigawa, and Hiroshi Mamitsuka
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- 2006
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13. Block Merging for Off-Line Compression.
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Raymond Wan 0001 and Alistair Moffat
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- 2002
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14. Query Modification through External Sources to Support Clinical Decisions.
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Raymond Wan 0001, Ting-Fung Chan, and Jannifer Hiu-Kwan Man
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- 2014
15. Re-Store: A System for Compressing, Browsing, and Searching Large Documents (Invited Paper).
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Alistair Moffat and Raymond Wan 0001
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- 2001
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16. Effective compression for the web: exploiting document linkages.
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Raymond Wan 0001 and Alistair Moffat
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- 2001
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17. Transformations for the compression of FASTQ quality scores of next-generation sequencing data.
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Raymond Wan 0001, Vo Ngoc Anh, and Kiyoshi Asai
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- 2012
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18. Block merging for off-line compression.
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Raymond Wan 0001 and Alistair Moffat
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- 2007
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19. Review of 'Genomic Perl From Bioinformatics Basics to Working Code by Rex A. Dwyer', Cambridge University Press 2003, 0-521-80177-X.
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Raymond Wan 0001
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- 2005
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20. ViralFusionSeq: accurately discover viral integration events and reconstruct fusion transcripts at single-base resolution.
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Jing-Woei Li, Raymond Wan 0001, Chi-Shing Yu, Ngai Na Co, Nathalie Wong, and Ting-Fung Chan
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- 2013
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21. Disease characteristics, effectiveness, and safety of vestronidase alfa for the treatment of patients with mucopolysaccharidosis VII in a novel, longitudinal, multicenter disease monitoring program
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Roberto Giugliani, Antonio Gonzalez-Meneses, Maurizio Scarpa, Barbara Burton, Raymond Wang, Esmeralda Martins, Esmeralda Oussoren, Julia B. Hennermann, Brigitte Chabrol, Christina L. Grant, Angela Sun, Consuelo Durand, Joel Hetzer, Betsy Malkus, Deborah Marsden, and J. Lawrence Merritt II
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Lysosomal storage disease ,Non-immune hydrops fetalis ,β-glucuronidase deficiency ,Mucopolysaccharidosis VII ,MPS VII ,Medicine - Abstract
Abstract Background Mucopolysaccharidosis VII (MPS VII) is an ultra-rare, autosomal recessive, debilitating, progressive lysosomal storage disease caused by reduced activity of β-glucuronidase (GUS) enzyme. Vestronidase alfa (recombinant human GUS) intravenous enzyme replacement therapy is an approved treatment for patients with MPS VII. Methods This disease monitoring program (DMP) is an ongoing, multicenter observational study collecting standardized real-world data from patients with MPS VII (N ≈ 50 planned) treated with vestronidase alfa or any other management approach. Data are monitored and recorded in compliance with Good Clinical Practice guidelines and planned interim analyses of captured data are performed annually. Here we summarize the safety and efficacy outcomes as of 17 November 2022. Results As of the data cutoff date, 35 patients were enrolled: 28 in the Treated Group and seven in the Untreated Group. Mean (SD) age at MPS VII diagnosis was 4.5 (4.0) years (range, 0.0 to 12.4 years), and mean (SD) age at DMP enrollment was 13.9 (11.1) years (range, 1.5 to 50.2 years). Ten patients (29%) had a history of nonimmune hydrops fetalis. In the 23 patients who initiated treatment prior to DMP enrollment, substantial changes in mean excretion from initial baseline to DMP enrollment were observed for the three urinary glycosaminoglycans (uGAGs): dermatan sulfate (DS), -84%; chondroitin sulfate (CS), -55%; heparan sulfate (HS), -42%. Also in this group, mean reduction from initial baseline to months 6, 12, and 24 were maintained for uGAG DS (-84%, -87%, -89%, respectively), CS (-70%, -71%, -76%, respectively), and HS (+ 3%, -32%, and − 41%, respectively). All adverse events (AEs) were consistent with the known vestronidase alfa safety profile. No patients discontinued vestronidase alfa. One patient died. Conclusions To date, the DMP has collected invaluable MPS VII disease characteristic data. The benefit-risk profile of vestronidase alfa remains unchanged and favorable for its use in the treatment of pediatric and adult patients with MPS VII. Reductions in DS and CS uGAG demonstrate effectiveness of vestronidase alfa to Month 24. Enrollment is ongoing.
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- 2024
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22. Passage Retrieval with Vector Space and Query-Level Aspect Models.
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Raymond Wan 0001, Vo Ngoc Anh, and Hiroshi Mamitsuka
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- 2007
23. Combining Vector-Space and Word-Based Aspect Models for Passage Retrieval.
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Raymond Wan 0001, Ichigaku Takigawa, Hiroshi Mamitsuka, and Vo Ngoc Anh
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- 2006
24. Mitochondrial protein cleavage site predictor.
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Yoshinori Fukasawa, Raymond Wan 0001, Szu-Chin Fu, Junko Tsuji, Noriyuki Sakiyama, Kenichiro Imai, and Paul Horton
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- 2010
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25. Development of genome-wide polygenic risk scores for lipid traits and clinical applications for dyslipidemia, subclinical atherosclerosis, and diabetes cardiovascular complications among East Asians
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Miao Hu, Ip-Tim Lau, Grace Kam, Samuel Fung, Chiu-Chi Tsang, Shing-chung Siu, Man-Wo Tsang, Ronald C.W. Ma, Risa Ozaki, Andrea O.Y. Luk, Ka-fai Lee, June K. Y. Li, Heung Man Lee, Weichuan Yu, Cadmon King Poo Lim, Stephen Kwok-Wing Tsui, Raymond Wan, Stanley Hok-King Lo, Maggie C.Y. Ng, Grace Hui, Yuk-Lun Cheng, Alex C.W. Ng, Claudia Ha Ting Tam, Cheuk-Chun Szeto, Emmy Y. F. Lau, Nelson L.S. Tang, Wing Hung Tam, Alice P.S. Kong, Chun-Chung Chow, Vincent T.F. Yeung, Elaine Chow, Eric S.H. Lau, Kam-Piu Lau, Yu Huang, Hui-Yao Lan, Brian Tomlinson, Baoqi Fan, Guozhi Jiang, Jenny Y. Y. Leung, Juliana C.N. Chan, and Wing-Yee So
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0301 basic medicine ,Multifactorial Inheritance ,Diabetic Cardiomyopathies ,lcsh:Medicine ,Coronary Disease ,Disease ,Type 2 diabetes ,030204 cardiovascular system & hematology ,Carotid Intima-Media Thickness ,0302 clinical medicine ,Risk Factors ,Genetics (clinical) ,education.field_of_study ,Lipids ,Molecular Medicine ,Female ,Risk assessment ,Adult ,medicine.medical_specialty ,lcsh:QH426-470 ,Adolescent ,Diabetes cardiovascular complications ,East Asians ,Population ,03 medical and health sciences ,Asian People ,Internal medicine ,Diabetes mellitus ,Genetics ,medicine ,Humans ,Genetic Predisposition to Disease ,Subclinical atherosclerosis ,education ,Molecular Biology ,Dyslipidemias ,business.industry ,Research ,lcsh:R ,medicine.disease ,Atherosclerosis ,lcsh:Genetics ,Polygenic risk scores ,030104 developmental biology ,Diabetes Mellitus, Type 2 ,Lipid traits ,Polygenic risk score ,business ,Body mass index ,Dyslipidemia ,Genome-Wide Association Study - Abstract
Background The clinical utility of personal genomic information in identifying individuals at increased risks for dyslipidemia and cardiovascular diseases remains unclear. Methods We used data from Biobank Japan (n = 70,657–128,305) and developed novel East Asian-specific genome-wide polygenic risk scores (PRSs) for four lipid traits. We validated (n = 4271) and subsequently tested associations of these scores with 3-year lipid changes in adolescents (n = 620), carotid intima-media thickness (cIMT) in adult women (n = 781), dyslipidemia (n = 7723), and coronary heart disease (CHD) (n = 2374 cases and 6246 controls) in type 2 diabetes (T2D) patients. Results Our PRSs aggregating 84–549 genetic variants (0.251 r) r − 103 P − 75) and 3-year lipid changes (1.4 × 10− 6 P β ± SE = 0.052 ± 0.002), 11.7% in TG (β ± SE = 0.111 ± 0.006), 5.8% in HDL-C (β ± SE = 0.057 ± 0.003), and 8.4% in LDL-C (β ± SE = 0.081 ± 0.004) per one standard deviation increase in the corresponding PRS. However, their predictive power was attenuated in T2D patients (0.183 r − 3 P − 10 P β ± SE = 0.011 ± 0.005, Ptrend = 0.0182). Independent of conventional risk factors, the quintile of PRSs for TC [OR (95% CI) = 1.07 (1.03–1.11)], TG [OR (95% CI) = 1.05 (1.01–1.09)], and LDL-C [OR (95% CI) = 1.05 (1.01–1.09)] were significantly associated with increased risk of CHD in T2D patients (4.8 × 10− 4 P Conclusions The PRSs derived and validated here highlight the potential for early genomic screening and personalized risk assessment for cardiovascular disease.
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- 2020
26. 108-OR: Application of a European Genetic Risk Score for Type 1 Diabetes in a Han-Chinese Population
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Michael N. Weedon, William Hagopian, Juliana C.N. Chan, Claudia H. T. Tam, Ronald C.W. Ma, Seth A. Sharp, Richard A. Oram, and Raymond Wan
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Type 1 diabetes ,Han chinese ,business.industry ,Endocrinology, Diabetes and Metabolism ,Internal Medicine ,Medicine ,Genetic risk ,business ,medicine.disease ,Demography - Abstract
Increasing childhood obesity and young-onset diabetes have made clinically distinguishing between type 1 diabetes (T1D) and type 2 diabetes (T2D) more difficult. A Genetic risk score (GRS) for T1D was developed in European populations, with good discrimination of diabetes type. Here, we aim to evaluate T1D-GRS in a Han-Chinese cohort. We utilized whole genome genotyping data for 533 nondiabetic controls, 182 patients with T1D, and 6,209 patients with T2D. We computed the T1D-GRS for each subject using 30 T1D associated SNPs. The mean ages of the controls, T1D, and T2D subjects were 47±11, 32±15, and 57±13 years, respectively. Violin plots of the GRS for the 3 groups are shown in the Figure, along with p-values. The mean GRS across the controls, T1D, and T2D were 0.242, 0.256, and 0.242, respectively. The area under the curve (AUC) for GRS in T1D vs. T2D was 0.677 (95% CI: 0.635-0.718), and 0.678 (95% CI: 0.631-0.725) for T1D patients vs. controls. We conclude that T1D-GRS detects significant differences in T1D genetic risk between T1D and non-T1D in a Han-Chinese population, with subjects with T1D having a higher score. Further refinement incorporating single nucleotide polymorphisms (SNPs) specific for a Han-Chinese population is currently underway, and is expected to further improve classification of T1D in Han-Chinese. Disclosure R. Wan: None. S.A. Sharp: None. C.H.T. Tam: None. M.N. Weedon: None. J.C. Chan: None. W. Hagopian: Consultant; Self; Novo Nordisk Inc. R.A. Oram: None. R.C. Ma: Advisory Panel; Self; AstraZeneca. Stock/Shareholder; Self; GemVCare. Other Relationship; Self; AstraZeneca, Bayer Healthcare Pharmaceuticals Inc., Merck & Co., Inc., Novo Nordisk A/S, Pfizer Inc., Sanofi-Aventis, Tricida Inc. Funding Research Grants Council (T12-402/13N); Research Impact Fund (CUR4012-18)
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- 2020
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27. Large-Scale Expansion of Human iPSC-Derived Skeletal Muscle Cells for Disease Modeling and Cell-Based Therapeutic Strategies
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Tom J.M. van Gestel, Tom H. Cheung, Wilfred F. J. van IJcken, Gerben J. Schaaf, Stijn L.M. in 't Groen, Ans T. van der Ploeg, W.W.M. Pim Pijnappel, Erik van der Wal, Pablo Herrero-Hernandez, Raymond Wan, Mike Broeders, Clinical Genetics, Pediatrics, Internal Medicine, and Cell biology
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Resource ,0301 basic medicine ,Satellite Cells, Skeletal Muscle ,Cellular differentiation ,Induced Pluripotent Stem Cells ,Muscle Fibers, Skeletal ,Cell ,Cell- and Tissue-Based Therapy ,Biology ,Biochemistry ,03 medical and health sciences ,SDG 3 - Good Health and Well-being ,disease modeling ,Glycogen storage disease type II ,skeletal muscle differentiation ,Genetics ,medicine ,Lysosomal storage disease ,Humans ,Regeneration ,Progenitor cell ,Induced pluripotent stem cell ,CRISPR/Cas9 ,satellite cells ,muscle regeneration ,gene editing ,Glycogen Storage Disease Type II ,Myogenesis ,Gene Expression Profiling ,Pompe disease ,Computational Biology ,Skeletal muscle ,Cell Differentiation ,Cell Biology ,metabolic disease ,medicine.disease ,Cell biology ,030104 developmental biology ,medicine.anatomical_structure ,lysosomal storage disease ,Batch Cell Culture Techniques ,pluripotent stem cells ,CRISPR-Cas Systems ,Stem Cell Transplantation ,Developmental Biology - Abstract
Summary Although skeletal muscle cells can be generated from human induced pluripotent stem cells (iPSCs), transgene-free protocols include only limited options for their purification and expansion. In this study, we found that fluorescence-activated cell sorting-purified myogenic progenitors generated from healthy controls and Pompe disease iPSCs can be robustly expanded as much as 5 × 1011-fold. At all steps during expansion, cells could be cryopreserved or differentiated into myotubes with a high fusion index. In vitro, cells were amenable to maturation into striated and contractile myofibers. Insertion of acid α-glucosidase cDNA into the AAVS1 locus in iPSCs using CRISPR/Cas9 prevented glycogen accumulation in myotubes generated from a patient with classic infantile Pompe disease. In vivo, the expression of human-specific nuclear and sarcolemmar antigens indicated that myogenic progenitors engraft into murine muscle to form human myofibers. This protocol is useful for modeling of skeletal muscle disorders and for using patient-derived, gene-corrected cells to develop cell-based strategies., Highlights • Transgene-free protocol for generation and expansion of myogenic progenitors • Differentiation into contractile skeletal muscle cells in vitro • Correction of glycogen accumulation in Pompe disease using CRISPR/cas9 • Contribution to muscle regeneration in vivo, Van der Wal et al. present a robust protocol for the transgene-free generation and purification of myogenic progenitors from human iPSCs and for their expansion up to 5 × 1011-fold. After gene editing in vitro, these myogenic progenitors matured into contractile skeletal muscle cells, reversing Pompe disease pathology. In vivo, myogenic progenitors contributed to muscle regeneration.
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- 2018
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28. Cleaning microarray expression data using Markov random fields based on profile similarity.
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Raymond Wan 0001, Hiroshi Mamitsuka, and Kiyoko F. Aoki
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- 2005
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29. Interactive Phrase Browsing Within Compressed Text.
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Raymond Wan 0001 and Alistair Moffat
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- 2001
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30. Dek Modulates Global Intron Retention to Control Quiescence Exit in Muscle Stem Cells
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Tom H. Cheung, Shaoyuan Luan, Raymond Wan, and Lu Yue
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medicine.anatomical_structure ,RNA splicing ,Intron ,medicine ,Skeletal muscle ,Cell cycle ,Stem cell ,Biology ,Gene ,Post-transcriptional regulation ,Adult stem cell ,Cell biology - Abstract
Quiescent adult stem cells have the ability to respond rapidly to external stimuli, but mechanisms of such rapid activation remain elusive. Using quiescent skeletal muscle stem cells (QSCs), we showed that intron retention (IR) is prevalent. Genes possessing IR are essential for various fundamental cellular functions including RNA splicing, protein translation, cell cycle entry and lineage specification. Further analysis revealed that IR is a post-transcriptional mechanism that regulates QSC quiescence exit, which is dependent on the phosphorylated-Dek protein. While Dek is absent in QSCs, overexpression of Dek in QSC in vivo results in a global decrease of IR, quiescence exit, and consequently undermine muscle regeneration. Moreover, IR analysis on public RNA-seq data shows that other quiescent adult stem cells are enriched with retained introns, indicating IR as a feature of quiescent adult stem cells. Altogether, these findings suggest that intron retention plays an important role in stem cell quiescence exit.
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- 2019
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31. Pernicious anemia in Chinese: a study of 181 patients in a Hong Kong hospital
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Chan, Joyce Chee Wun, Liu, Herman Sung Yu, Kho, Bonnie Chi Sang, Sim, Joycelyn Pui Yin, Lau, Thomas Kwan Hang, Luk, Yiu Wing, Chu, Raymond Wan, Cheung, Florence Man Fung, Choi, Frankie Pak Tat, and Ma, Edmond Shiu Kwan
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Pernicious anemia -- Diagnosis ,Pernicious anemia -- Case studies - Published
- 2006
32. Biomarkers of Glycosaminoglycans (GAG) accumulation in patients with mucopolysaccharidosis type VI—LeukoGAG, Corneal Opacification (COM) and Carotid Intima Media Thickening (CIMT)
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Young Bae Sohn, Raymond Wang, Jane Ashworth, Pierre Broqua, Mireille Tallandier, Jean-Louis Abitbol, Erin Jozwiak, Laura Pollard, Timothy C. Wood, Tariq Aslam, and Paul R. Harmatz
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Mucopolysaccharidosis type VI ,Leukocyte GAG ,Skin GAG ,Corneal opacification measurements ,Carotid intima media thickness ,Medicine (General) ,R5-920 ,Biology (General) ,QH301-705.5 - Abstract
Mucopolysaccharidosis type VI (MPS VI) is an autosomal recessive lysosomal storage disorder characterized by deficient activity of arylsulfatase B enzyme (ASB) resulting in cellular accumulation of dermatan sulfate (DS) and chondroitin sulfate (CS) that leads to cell injury. Urinary glycosaminoglycans (GAG) are often used as a biomarker in MPS diseases for diagnosis and to monitor treatment efficacy. This study evaluated leukocyte GAGs (leukoGAG) and skin GAGs as alternate biomarkers representing intracellular GAG changes in patients with MPS VI and treated with enzyme replacement therapy (ERT). In addition, we evaluated corneal opacification measurements (COM) and carotid intima media thickness (CIMT) as indicators of GAG accumulation and tissue injury. The study was performed in a serial two-step design in a single center. A quantitative method to measure leukoGAG levels in leukocytes was developed in Study 1 to compare the GAG levels between MPS VI patients and a control group and to assess correlations between leukoGAG and urineGAG. Study 2 validated the leukoGAG measurement, assessed the effect of ERT infusion on leukoGAG and ASB activity in leukocytes, identified correlations between leukoGAG and other biomarkers, and assessed differences in GAG accumulation between MPS VI patients and control subjects. In Study 1, leukoCS and leukoDS levels were significantly higher in the MPS VI group than the control group (leukoCS: 37.9 ± 10.2 and 2.9 ± 1.5 μg/μg protein, respectively, p = 0.005; leukoDS: 0.26 ± 0.2 and 0.0 ± 0.0 μg/μg protein, respectively, p = 0.028) with positive correlations between leukoCS and urine CS and leukoDS and urineDS. In Study 2, leukoCS (32.0 ± 11.8 vs 6.9 ± 3.1 μg/mg protein, p = 0.005) and leukoDS (0.4 ± 0.1 and 0.2 ± 0.1 μg/mg protein, p = 0.020) were significantly higher compared with control subjects. Thus, these results highlight the potential of leukoGAG as a new biomarker representing intracellular GAG accumulation in MPS VI patients and may be valuable for patient management.
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- 2024
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33. O30: REKLAIM: A first in human phase Ib clinical trial of FBX-101 (AAVrh10.GALC) intravenously administered after UCBT for infantile Krabbe disease
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Maria Escolar, Mark Vander Lugt, Raymond Wang, Juan Ruiz, Michele Poe, and Paul Szabolcs
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Genetics ,QH426-470 ,Medicine - Published
- 2024
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34. P261: Vestronidase alfa for the treatment of mucopolysaccharidosis VII (MPS VII): Updated results from a longitudinal, multicenter disease monitoring program (DMP)
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Roberto Giugliani, Antonio Gonzalez-Meneses, Christina Grant, Maurizio Scarpa, Angela Sun, Raymond Wang, Barbara Burton, Ans van der Ploeg, Esmeralda Martins, Consuelo Durand, Brigitte Chabrol, Joel Hetzer, Deborah Marsden, and J. Lawrence Merritt, II
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Genetics ,QH426-470 ,Medicine - Published
- 2024
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35. OMBlast: alignment tool for optical mapping using a seed-and-extend approach
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Pui-Yan Kwok, Alden King-Yung Leung, Tsz-Piu Kwok, Ting-Fung Chan, Kevin Y. Yip, Raymond Wan, Ming Xiao, and Hancock, John
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0301 basic medicine ,Computer science ,computer.software_genre ,Biochemistry ,Genome ,Mathematical Sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Software ,Computer graphics (images) ,Optical Restriction Mapping ,computer.programming_language ,Genomics ,Biological Sciences ,Original Papers ,Computer Science Applications ,Computational Mathematics ,Computational Theory and Mathematics ,Data mining ,Sequence Analysis ,Statistics and Probability ,Java ,Bioinformatics ,Sequence analysis ,Bioengineering ,Sequence alignment ,Saccharomyces cerevisiae ,Set (abstract data type) ,03 medical and health sciences ,Information and Computing Sciences ,Optical mapping ,Escherichia coli ,Animals ,Humans ,Caenorhabditis elegans ,Molecular Biology ,Gene ,business.industry ,SIGNAL (programming language) ,Sequence Analysis, DNA ,DNA ,Genome Analysis ,Range (mathematics) ,030104 developmental biology ,chemistry ,Generic health relevance ,business ,Sequence Alignment ,computer ,030217 neurology & neurosurgery - Abstract
Motivation Optical mapping is a technique for capturing fluorescent signal patterns of long DNA molecules (in the range of 0.1–1 Mbp). Recently, it has been complementing the widely used short-read sequencing technology by assisting with scaffolding and detecting large and complex structural variations (SVs). Here, we introduce a fast, robust and accurate tool called OMBlast for aligning optical maps, the set of signal locations on the molecules generated from optical mapping. Our method is based on the seed-and-extend approach from sequence alignment, with modifications specific to optical mapping. Results Experiments with both synthetic and our real data demonstrate that OMBlast has higher accuracy and faster mapping speed than existing alignment methods. Our tool also shows significant improvement when aligning data with SVs. Availability and Implementation OMBlast is implemented for Java 1.7 and is released under a GPL license. OMBlast can be downloaded from https://github.com/aldenleung/OMBlast and run directly on machines equipped with a Java virtual machine. Supplementary information Supplementary data are available at Bioinformatics online
- Published
- 2016
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36. HAMSTER: visualizing microarray experiments as a set of minimum spanning trees.
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Raymond Wan 0001, Larisa Kiseleva, Hajime Harada, Hiroshi Mamitsuka, and Paul Horton
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- 2009
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37. Dek Modulates Global Intron Retention during Muscle Stem Cells Quiescence Exit
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Lu Yue, Wenshu Zeng, Tom H. Cheung, Shaoyuan Luan, and Raymond Wan
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Satellite Cells, Skeletal Muscle ,Biology ,General Biochemistry, Genetics and Molecular Biology ,Transcriptome ,Mice ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Animals ,Humans ,RNA Processing, Post-Transcriptional ,Poly-ADP-Ribose Binding Proteins ,Molecular Biology ,Post-transcriptional regulation ,Cells, Cultured ,030304 developmental biology ,Oncogene Proteins ,0303 health sciences ,Intron ,Skeletal muscle ,Cell Differentiation ,Cell Biology ,Introns ,Cell biology ,DNA-Binding Proteins ,Mice, Inbred C57BL ,HEK293 Cells ,medicine.anatomical_structure ,RNA splicing ,Phosphorylation ,Stem cell ,030217 neurology & neurosurgery ,Developmental Biology ,Adult stem cell - Abstract
Summary Adult stem cells are essential for tissue regeneration. However, the mechanisms underlying the activation of quiescent adult stem cells remain elusive. Using skeletal muscle stem cells, also called satellite cells (SCs), we demonstrate prevalent intron retention (IR) in the transcriptome of quiescent SCs (QSCs). Intron-retained transcripts found in QSCs are essential for fundamental functions including RNA splicing, protein translation, cell-cycle entry, and lineage specification. Further analysis reveals that phosphorylated Dek protein modulates IR during SC quiescence exit. While Dek protein is absent in QSCs, Dek overexpression in vivo results in a global decrease of IR, quiescence dysregulation, premature differentiation of QSCs, and undermined muscle regeneration. Moreover, IR analysis on hundreds of public RNA-seq data show that IR is conserved among quiescent adult stem cells. Altogether, we illustrate IR as a conserved post-transcriptional regulation mechanism that plays an important role during stem cell quiescence exit.
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- 2020
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38. High-Dimensional Single-Cell Cartography Reveals Novel Skeletal Muscle-Resident Cell Populations
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Gary J. He, Aurélien Corneau, Tom H. Cheung, Elisa Negroni, Hiroshi Sakai, M. Mona Siu, Raymond Wan, Shahragim Tajbakhsh, Lorenzo Giordani, Justin Y. C. Law, Fabien Le Grand, Centre de recherche en Myologie – U974 SU-INSERM, Institut National de la Santé et de la Recherche Médicale (INSERM)-Sorbonne Université (SU), Hong Kong University of Science and Technology (HKUST), Cellules Souches et Développement / Stem Cells and Development, Institut Pasteur [Paris]-Centre National de la Recherche Scientifique (CNRS), Max Planck Institute for Heart and Lung Research (MPI-HLR), Max-Planck-Gesellschaft, Plateforme Cytométrie Pitié-Salpêtrière (LUMIC-CYPS), Unité Mixte de Service d'Imagerie et de Cytométrie [CHU Saint-Antoine] (UMS LUMIC), Institut National de la Santé et de la Recherche Médicale (INSERM)-Sorbonne Université (SU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), This study was supported by ANR/RGC (Agence Nationale pour la Recherche/Research Grant Council) grant ANR-14-CE11-0026/A-HKUST604/14 (to F.L.G. and T.C.), an Association Française contre les Myopathies/AFM Telethon grant to F.L.G., the Hong Kong Research Grant Council (research grants C6015-14G, C6003-14G, C6009-15G, AoE/M-604/16, and T13-607/12R to T.H.C.), and the Croucher Innovation Award (T.H.C.)., We thank Catherine Blanc (CyPS Facility) for technical support. We thank Bruno Cadot, Christophe Combadière, Glenda Comai, and Vincent Mouly for providing transgenic mice. We thank Gilian Butler-Browne, Florian Bentzinger, David Sassoon, Rémi Mounier, and Capucine Trollet for commenting on the manuscript., Centre de Recherche en Myologie, Institut Pasteur [Paris] (IP)-Centre National de la Recherche Scientifique (CNRS), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Unité Mixte de Service d'Imagerie et de Cytométrie [CHU Saint-Antoine] (UMS LUMIC), and Institut National de la Santé et de la Recherche Médicale (INSERM)-Sorbonne Université (SU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Sorbonne Université (SU)
- Subjects
MESH: Muscle Fibers, Skeletal/metabolism ,Cell type ,MESH: Muscle Fibers, Skeletal/cytology ,Satellite Cells, Skeletal Muscle ,[SDV]Life Sciences [q-bio] ,Cell ,Muscle Fibers, Skeletal ,skeletal muscle stem cells ,Biology ,Muscle Development ,Myoblasts ,03 medical and health sciences ,Mice ,0302 clinical medicine ,MESH: Stem Cells/metabolism ,medicine ,Compartment (development) ,MESH: Myoblasts/metabolism ,MESH: Satellite Cells, Skeletal Muscle/metabolism ,Animals ,MESH: Animals ,Cell Lineage ,MESH: Satellite Cells, Skeletal Muscle/cytology ,MESH: Cell Lineage/genetics ,Molecular Biology ,MESH: Mice ,030304 developmental biology ,satellite cells ,0303 health sciences ,single-cell RNA-seq ,Regeneration (biology) ,MESH: Cell Differentiation/genetics ,Stem Cells ,Mesenchymal stem cell ,Scleraxis ,MESH: Myoblasts/cytology ,Skeletal muscle ,Cell Differentiation ,Cell Biology ,Cell biology ,Transplantation ,MESH: Stem Cells/cytology ,medicine.anatomical_structure ,MESH: Muscle Development/genetics ,CyTOF ,Single-Cell Analysis ,030217 neurology & neurosurgery ,MESH: Single-Cell Analysis - Abstract
International audience; Adult tissue repair and regeneration require stem-progenitor cells that can self-renew and generate differentiated progeny. Skeletal muscle regenerative capacity relies on muscle satellite cells (MuSCs) and their interplay with different cell types within the niche. However, our understanding of skeletal muscle tissue cellular composition is limited. Here, using a combined approach of single-cell RNA sequencing and mass cytometry, we precisely mapped 10 different mononuclear cell types in adult mouse muscle. We also characterized gene signatures and determined key discriminating markers of each cell type. We identified two previously understudied cell populations in the interstitial compartment. One expresses the transcription factor scleraxis and generated tenocytes in vitro. The second expresses markers of smooth muscle and mesenchymal cells (SMMCs) and, while distinct from MuSCs, exhibited myogenic potential and promoted MuSC engraftment following transplantation. The blueprint presented here yields crucial insights into muscle-resident cell-type identities and can be exploited to study muscle diseases.
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- 2018
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39. High-dimensional single-cell cartography reveals novel skeletal muscle resident cell populations
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Lorenzo Giordani, Shahragim Tajbakhsh, Tom H. Cheung, M. Mona Siu, Fabien Le Grand, Justin Y. C. Law, Elisa Negroni, Raymond Wan, Hiroshi Sakai, and Gary J. He
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0303 health sciences ,Cell type ,Regeneration (biology) ,Scleraxis ,Mesenchymal stem cell ,Cell ,Skeletal muscle ,Biology ,Cell biology ,Transplantation ,03 medical and health sciences ,0302 clinical medicine ,medicine.anatomical_structure ,medicine ,Progenitor cell ,030217 neurology & neurosurgery ,030304 developmental biology - Abstract
Adult tissue repair and regeneration require the activation of resident stem/progenitor cells that can self-renew and generate differentiated progeny. The regenerative capacity of skeletal muscle relies on muscle satellite cells (MuSCs) and their interplay with different cell types within the niche. Yet, our understanding of the cells that compose the skeletal muscle tissue is limited and molecular definitions of the principal cell types are lacking. Using a combined approach of single-cell RNA-sequencing and mass cytometry, we precisely mapped the different cell types in adult skeletal muscle tissue and highlighted previously overlooked populations. We identified known functional populations, characterized their gene signatures, and determined key markers. Among the ten main cell populations present in skeletal muscle, we found an unexpected complexity in the interstitial compartment and identified two new cell populations. One express the transcription factor Scleraxis and generate tenocyte-like cells. The second express smooth muscle and mesenchymal cell markers (SMMCs). While distinct from MuSCs, SMMCs are endowed with myogenic potential and promote MuSC engraftment following transplantation. Our high-dimensional single-cell atlas uncovers principles of an adult tissue composition and can be exploited to reveal unknown cellular sub-fractions that contribute to tissue regeneration.
- Published
- 2018
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40. High-Dimensional Single-Cell Cartography Reveals Novel Skeletal Muscle Resident Cell Populations
- Author
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Aurélien Corneau, Justin Y. C. Law, Lorenzo Giordani, M. Mona Siu, Hiroshi Sakai, Shahragim Tajbakhsh, Fabien Le Grand, Gary J. He, Tom H. Cheung, Raymond Wan, and Elisa Negroni
- Subjects
Cell type ,education.field_of_study ,Scleraxis ,Population ,Mesenchymal stem cell ,Cell ,Skeletal muscle ,Biology ,Cell biology ,Transplantation ,medicine.anatomical_structure ,medicine ,Progenitor cell ,education - Abstract
Adult tissue repair and regeneration require the activation of resident stem and progenitor cells that can self-renew and generate differentiated progeny. The regenerative capacity of skeletal muscle relies on muscle satellite cells (MuSCs) and their interplay with different cell types within the niche. However, our understanding of the cells that compose skeletal muscle tissue is limited and molecular definitions of the principal cell types are lacking. Here, using a novel combined approach of single-cell RNA-sequencing and mass cytometry, we precisely mapped 10 different cell types in adult mouse skeletal muscle, including two previously unidentified populations. We also characterized the gene signatures and determined the key discriminating markers of each cell type. We found an unexpected complexity in the interstitial compartment, wherein two new cell populations were identified. One population expressed the transcription factor Scleraxis and generated tenocytes in vitro. The second population expressed smooth muscle and mesenchymal cell (SMMC) markers and, while distinct from MuSCs, exhibited myogenic potential and promoted MuSC engraftment following transplantation. The blueprint presented here yields crucial insights into muscle-resident cell type identities and can be exploited to study muscle ageing and diseases.
- Published
- 2018
- Full Text
- View/download PDF
41. NovelChlamydia trachomatisStrains in Heterosexual Sex Partners, Indianapolis, Indiana, USA
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James A. Williams, Linda He, Deborah Dean, J. Dennis Fortenberry, Byron E. Batteiger, Raymond Wan, and Arissa Ma
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Adult ,Male ,Microbiology (medical) ,Indiana ,Adolescent ,Genotype ,Epidemiology ,Chlamydia trachomatis ,Biology ,medicine.disease_cause ,STIs ,partner tracing ,Young Adult ,Phylogenetics ,recombinant strains ,medicine ,Humans ,Typing ,heterosexual partners ,Heterosexuality ,bacteria ,Phylogeny ,sexually transmitted infections ,USA ,Recombination, Genetic ,Genetics ,Novel Chlamydia trachomatis Strains in Heterosexual Sex Partners, Indianapolis, Indiana, USA ,Phylogenetic tree ,Research ,Strain (biology) ,Sex partners ,Chlamydia Infections ,Virology ,3. Good health ,Sexual Partners ,Infectious Diseases ,Genes, Bacterial ,Multilocus sequence typing ,Female ,Multilocus Sequence Typing ,MLST - Abstract
Use of multilocus sequence typing may help identify new strains in at-risk populations., Chlamydia trachomatis causes a high number of sexually transmitted infections worldwide, but reproducible and precise strain typing to link partners is lacking. We evaluated multilocus sequence typing (MLST) for this purpose by detecting sequence types (STs) concordant for the ompA genotype, a single-locus typing standard. We tested samples collected during April 2000–October 2003 from members of established heterosexual partnerships (dyads) in the Indianapolis, Indiana, USA, area who self-reported being coital partners within the previous 30 days. C. trachomatis DNA from 28 dyads was tested by MLST; sequences were aligned and analyzed for ST and phylogenetic relationships. MLST detected 9 C. trachomatis STs, 4 unique to Indianapolis; STs were identical within each dyad. Thirteen unique strains were identified; 9 (32%) dyads harbored novel recombinant strains that phylogenetically clustered with strains comprising the recombinants. The high rate of novel C. trachomatis recombinants identified supports the use of MLST for transmission and strain diversity studies among at-risk populations.
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- 2014
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42. L’analyse par cytométrie de masse des muscles âgés et dystrophiques permet d’identifier des nouvelles populations distinctes des cellules satellites
- Author
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Justin Y. C. Law, M. Mona Siu, Shahragim Tajbakhsh, Tom H. Cheung, Raymond Wan, Gary J. He, Fabien Le Grand, Elisa Negroni, Hiroshi Sakai, and Lorenzo Giordani
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Biology - Published
- 2018
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43. In Vitro Recombinants of Antibiotic-Resistant Chlamydia trachomatis Strains Have Statistically More Breakpoints than Clinical Recombinants for the Same Sequenced Loci and Exhibit Selection at Unexpected Loci
- Author
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Tara Srinivasan, Jennifer Duong, Albert Yen, Deborah Dean, Raymond Wan, and William J. Bruno
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Recombination, Genetic ,Genetics ,Base Sequence ,Strain (biology) ,Molecular Sequence Data ,Breakpoint ,Chlamydia trachomatis ,Articles ,Chlamydia Infections ,Biology ,medicine.disease_cause ,rpoB ,Microbiology ,Anti-Bacterial Agents ,Antibiotic resistance ,Phylogenetics ,Drug Resistance, Bacterial ,Horizontal gene transfer ,medicine ,Humans ,Genetic Engineering ,Molecular Biology ,Phylogeny ,Recombination - Abstract
Lateral gene transfer (LGT) is essential for generating between-strain genomic recombinants of Chlamydia trachomatis to facilitate the organism's evolution. Because there is no reliable laboratory-based gene transfer system for C. trachomatis , in vitro generation of recombinants from antibiotic-resistant strains is being used to study LGT. However, selection pressures imposed on in vitro recombinants likely affect statistical properties of recombination relative to naturally occurring clinical recombinants, including prevalence at particular loci. We examined multiple loci for 16 in vitro -derived recombinants of ofloxacin- and rifampin-resistant L 1 and D strains, respectively, grown with both antibiotics, and compared these with the same sequenced loci among 11 clinical recombinants. Breakpoints and recombination frequency were examined using phylogenetics, bioinformatics, and statistics. In vitro and clinical isolates clustered perfectly into two groups, without misclassification, using Ward's minimum variance based on breakpoint data. As expected, gyrA (confers ofloxacin resistance) and rpoB (confers rifampin resistance) had significantly more breakpoints among in vitro recombinants than among clinical recombinants ( P < 0.0001 and P = 0.02, respectively, using the Wilcoxon rank sum test). Unexpectedly, trpA also had significantly more breakpoints for in vitro recombinants ( P < 0.0001). There was also significant selection at other loci. The strongest bias was for ompA in strain D ( P = 3.3 × 10 −8 ). Our results indicate that the in vitro model differs statistically from natural recombination events. Additional genomic studies are needed to determine the factors responsible for the observed selection biases at unexpected loci and whether these are important for LGT to inform approaches for genetically manipulating C. trachomatis .
- Published
- 2012
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44. Transformations for the compression of FASTQ quality scores of next-generation sequencing data
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Vo Anh, Kiyoshi Asai, and Raymond Wan
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Statistics and Probability ,Lossless compression ,FASTQ format ,Computer science ,business.industry ,Sequence Analysis, DNA ,Lossy compression ,Data Compression ,computer.software_genre ,Biochemistry ,Computer Science Applications ,Computational Mathematics ,Software ,Computational Theory and Mathematics ,Data mining ,business ,Molecular Biology ,computer - Abstract
Motivation: The growth of next-generation sequencing means that more effective and efficient archiving methods are needed to store the generated data for public dissemination and in anticipation of more mature analytical methods later. This article examines methods for compressing the quality score component of the data to partly address this problem. Results: We compare several compression policies for quality scores, in terms of both compression effectiveness and overall efficiency. The policies employ lossy and lossless transformations with one of several coding schemes. Experiments show that both lossy and lossless transformations are useful, and that simple coding methods, which consume less computing resources, are highly competitive, especially when random access to reads is needed. Availability and implementation: Our C++ implementation, released under the Lesser General Public License, is available for download at http://www.cb.k.u-tokyo.ac.jp/asailab/members/rwan. Contact: rwan@cuhk.edu.hk Supplementary information: Supplementary data are available at Bioinformatics online.
- Published
- 2011
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45. Improving localization accuracy for non-invasive automated early left ventricular origin localization approach
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Shijie Zhou, Raymond Wang, Avery Seagren, Noah Emmert, James W. Warren, Paul J. MacInnis, Amir AbdelWahab, and John L. Sapp
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k-nearest neighbors (KNN) algorithm ,ventricular tachycardia ,pace-mapping ,radiofrequency ablation ,ECG ,Physiology ,QP1-981 - Abstract
Background: We previously developed a non-invasive approach to localize the site of early left ventricular activation origin in real time using 12-lead ECG, and to project the predicted site onto a generic LV endocardial surface using the smallest angle between two vectors algorithm (SA).Objectives: To improve the localization accuracy of the non-invasive approach by utilizing the K-nearest neighbors algorithm (KNN) to reduce projection errors.Methods: Two datasets were used. Dataset #1 had 1012 LV endocardial pacing sites with known coordinates on the generic LV surface and corresponding ECGs, while dataset #2 included 25 clinically-identified VT exit sites and corresponding ECGs. The non-invasive approach used “population” regression coefficients to predict the target coordinates of a pacing site or VT exit site from the initial 120-m QRS integrals of the pacing site/VT ECG. The predicted site coordinates were then projected onto the generic LV surface using either the KNN or SA projection algorithm.Results: The non-invasive approach using the KNN had a significantly lower mean localization error than the SA in both dataset #1 (9.4 vs. 12.5 mm, p < 0.05) and dataset #2 (7.2 vs. 9.5 mm, p < 0.05). The bootstrap method with 1,000 trials confirmed that using KNN had significantly higher predictive accuracy than using the SA in the bootstrap assessment with the left-out sample (p < 0.05).Conclusion: The KNN significantly reduces the projection error and improves the localization accuracy of the non-invasive approach, which shows promise as a tool to identify the site of origin of ventricular arrhythmia in non-invasive clinical modalities.
- Published
- 2023
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46. Generation of two induced pluripotent stem cell lines (CHOCi002-A and CHOCi003-A) from Pompe disease patients with compound heterozygous mutations in the GAA gene
- Author
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Chloe Christensen, Perla Heckman, Allisandra Rha, Shih-Hsin Kan, Jerry Harb, and Raymond Wang
- Subjects
Pompe disease ,Lysosomal storage disorder ,Induced pluripotent stem cells ,Sendai virus ,Biology (General) ,QH301-705.5 - Abstract
Pompe disease is an autosomal recessive lysosomal storage disease caused by pathogenic variants in GAA, which encodes an enzyme integral to glycogen catabolism, acid α-glucosidase. Disease-relevant cell lines are necessary to evaluate the efficacy of genotype-specific therapies. Dermal fibroblasts from two patients presenting clinically with Pompe disease were reprogrammed to induced pluripotent stem cells using the Sendai viral method. One patient is compound heterozygous for the c.258dupC (p.N87QfsX9) frameshift mutation and the c.2227C>T (p.Q743X) nonsense mutation. The other patient harbors the c.-32–13T>G splice variant and the c.1826dupA (p.Y609X) frameshift mutation in compound heterozygosity.
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- 2023
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47. Block merging for off-line compression
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Raymond Wan and Alistair Moffat
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Human-Computer Interaction ,Artificial Intelligence ,Computer Networks and Communications ,Software ,Information Systems - Published
- 2006
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48. P189: Vestronidase alfa for the treatment of mucopolysaccharidosis VII (MPS VII): Updated results from a novel, longitudinal, multicenter disease monitoring program
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Roberto Giugliani, Antonio Gonzalez-Meneses, Christina Grant, Maurizio Scarpa, Angela Sun, Raymond Wang, Joel Hetzer, Deborah Marsden, and J. Lawrence Merritt, II
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Genetics ,QH426-470 ,Medicine - Published
- 2023
- Full Text
- View/download PDF
49. Multiple bumps can enhance robustness to noise in continuous attractor networks.
- Author
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Raymond Wang and Louis Kang
- Subjects
Biology (General) ,QH301-705.5 - Abstract
A central function of continuous attractor networks is encoding coordinates and accurately updating their values through path integration. To do so, these networks produce localized bumps of activity that move coherently in response to velocity inputs. In the brain, continuous attractors are believed to underlie grid cells and head direction cells, which maintain periodic representations of position and orientation, respectively. These representations can be achieved with any number of activity bumps, and the consequences of having more or fewer bumps are unclear. We address this knowledge gap by constructing 1D ring attractor networks with different bump numbers and characterizing their responses to three types of noise: fluctuating inputs, spiking noise, and deviations in connectivity away from ideal attractor configurations. Across all three types, networks with more bumps experience less noise-driven deviations in bump motion. This translates to more robust encodings of linear coordinates, like position, assuming that each neuron represents a fixed length no matter the bump number. Alternatively, we consider encoding a circular coordinate, like orientation, such that the network distance between adjacent bumps always maps onto 360 degrees. Under this mapping, bump number does not significantly affect the amount of error in the coordinate readout. Our simulation results are intuitively explained and quantitatively matched by a unified theory for path integration and noise in multi-bump networks. Thus, to suppress the effects of biologically relevant noise, continuous attractor networks can employ more bumps when encoding linear coordinates; this advantage disappears when encoding circular coordinates. Our findings provide motivation for multiple bumps in the mammalian grid network.
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- 2022
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50. Distinct pathways of homologous recombination controlled by the SWS1–SWSAP1–SPIDR complex
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Rohit Prakash, Thomas Sandoval, Florian Morati, Jennifer A. Zagelbaum, Pei-Xin Lim, Travis White, Brett Taylor, Raymond Wang, Emilie C. B. Desclos, Meghan R. Sullivan, Hayley L. Rein, Kara A. Bernstein, Przemek M. Krawczyk, Jean Gautier, Mauro Modesti, Fabio Vanoli, and Maria Jasin
- Subjects
Science - Abstract
Human SWS1, SWSAP1, and SPIDR interact with RAD51, a critical protein for homology-directed repair. Here the authors reveal roles for the mouse SWS1–SWSAP1–SPIDR complex in inter-homolog recombination, including during meiosis, and sister chromatid exchange in BLM helicase deficient cells.
- Published
- 2021
- Full Text
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