1
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Tan MG, Singh N, Kirshen C, Tolkachjov SN. Association between pyoderma gangrenosum and autoimmune connective tissue disorders: A systematic review. Int J Dermatol 2024; 63:e92-e94. [PMID: 38402537 DOI: 10.1111/ijd.17088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2024] [Revised: 01/26/2024] [Accepted: 01/30/2024] [Indexed: 02/26/2024]
Affiliation(s)
- Marcus G Tan
- Division of Dermatology, University of Ottawa, Ottawa, ON, Canada
| | - Nupur Singh
- University of Tennessee Health Science Center, Memphis, TN, USA
| | - Carly Kirshen
- Division of Dermatology, University of Ottawa, Ottawa, ON, Canada
| | - Stanislav N Tolkachjov
- Epiphany Dermatology, Dallas, TX, USA
- Baylor University Medical Center, Dallas, TX, USA
- Department of Dermatology, University of Texas at Southwestern, Dallas, TX, USA
- Texas A&M College of Medicine, Dallas, TX, USA
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2
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Tan MG, Tolkachjov SN. Treatment of Pyoderma Gangrenosum. Dermatol Clin 2024; 42:183-192. [PMID: 38423680 DOI: 10.1016/j.det.2023.12.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2024]
Abstract
Pyoderma gangrenosum is a rare neutrophilic dermatosis that results in painful cutaneous ulcers and is frequently associated with underlying hematologic disorders, inflammatory bowel disease, or other autoimmune disorders. Pathogenesis involves an imbalance between proinflammatory and anti-inflammatory mediators, leading to tissue damage from neutrophils. First-line treatment options with the greatest evidence include systemic corticosteroids, cyclosporine, and tumor necrosis factor alpha inhibitors. Other steroid-sparing therapies such as dapsone, mycophenolate mofetil, intravenous immunoglobulin, and targeted biologic or small molecule inhibitors also have evidence supporting their use. Wound care and management of underlying associated disorders are critical parts of the treatment regimen.
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Affiliation(s)
- Marcus G Tan
- Division of Dermatology, University of Ottawa, 737 Parkdale Avenue, 4th Floor Dermatology, Ottawa, ON K1Y1J8, Canada.
| | - Stanislav N Tolkachjov
- Mohs Micrographic & Reconstructive Surgery, Epiphany Dermatology, Department of Dermatology, Baylor University Medical Center, University of Texas at Southwestern, Texas A&M University School of Medicine, 1640 FM 544, Suite 100, Lewisville, TX 75056, USA
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3
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Tan MG, Bailey AMJ, Dorus B, Kirchhof MG. Clinical Impacts of Omalizumab on the Psychiatric Comorbidities of Chronic Spontaneous Urticaria: A Systematic Review and Meta-Analysis. J Drugs Dermatol 2024; 23:e116-e117. [PMID: 38564395 DOI: 10.36849/jdd.7919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
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4
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Tan MG, Bailey AMJ, Toy J, Tolkachjov SN. Association of autoimmune hepatitis and cutaneous malignancies: a systematic review and meta-analysis. Int J Dermatol 2023; 62:e576-e578. [PMID: 37382026 DOI: 10.1111/ijd.16781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2023] [Revised: 06/08/2023] [Accepted: 06/16/2023] [Indexed: 06/30/2023]
Affiliation(s)
- Marcus G Tan
- Division of Dermatology, University of Ottawa, Ottawa, ON, Canada
| | | | - Jeffrey Toy
- Department of Dermatology & Skin Science, University of British Columbia, Vancouver, BC, Canada
| | - Stanislav N Tolkachjov
- Epiphany Dermatology, Dallas, TX, USA
- Baylor University Medical Center, Dallas, TX, USA
- Texas A&M School of Medicine, Dallas, TX, USA
- Department of Dermatology, University of Texas at Southwestern, Dallas, TX, USA
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5
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King A, Tan MG, Kirshen C, Tolkachjov SN. Isotretinoin for the management of moderate-to-severe seborrheic dermatitis: A systematic review. J Am Acad Dermatol 2023; 89:1063-1066. [PMID: 37453557 DOI: 10.1016/j.jaad.2023.07.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2023] [Revised: 07/01/2023] [Accepted: 07/02/2023] [Indexed: 07/18/2023]
Affiliation(s)
- Aliyah King
- Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Marcus G Tan
- Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada; Division of Dermatology, University of Ottawa and The Ottawa Hospital, Ottawa, Ontario, Canada
| | - Carly Kirshen
- Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada; Division of Dermatology, University of Ottawa and The Ottawa Hospital, Ottawa, Ontario, Canada
| | - Stanislav N Tolkachjov
- Epiphany Dermatology, Dallas, Texas; Baylor University Medical Center, Dallas, Texas; Department of Dermatology, University of Texas Southwestern, Dallas, Texas; Texas A&M College of Medicine, Dallas, Texas.
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6
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Bailey AMJ, Li HOY, Tan MG, Kirchhof MG. Association of hidradenitis suppurativa and malignancy: A systematic review and meta-analysis. J Eur Acad Dermatol Venereol 2023; 37:e1107-e1108. [PMID: 37143377 DOI: 10.1111/jdv.19136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Accepted: 04/24/2023] [Indexed: 05/06/2023]
Affiliation(s)
| | - Heidi Oi-Yee Li
- Division of Dermatology, The Ottawa Hospital, Ottawa, Ontario, Canada
| | - Marcus G Tan
- Division of Dermatology, The Ottawa Hospital, Ottawa, Ontario, Canada
| | - Mark G Kirchhof
- Division of Dermatology, The Ottawa Hospital, Ottawa, Ontario, Canada
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7
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Li HOY, Bailey AMJ, Pastukhova E, Tan MG, Kirchhof MG. Comorbid diagnosis of systemic lupus erythematosus in vitiligo: a systematic review and meta-analysis. Br J Dermatol 2023; 188:440-441. [PMID: 36680305 DOI: 10.1093/bjd/ljac038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 08/29/2022] [Accepted: 11/26/2022] [Indexed: 01/22/2023]
Affiliation(s)
- Heidi Oi-Yee Li
- Division of Dermatology, University of Ottawa and The Ottawa Hospital, Ottawa, ON, Canada
| | | | | | - Marcus G Tan
- Division of Dermatology, University of Ottawa and The Ottawa Hospital, Ottawa, ON, Canada
| | - Mark G Kirchhof
- Division of Dermatology, University of Ottawa and The Ottawa Hospital, Ottawa, ON, Canada.,Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
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8
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Tan MG, Yu AM, Macdonald J. A 5-year retrospective cohort study of basal cell carcinomas on the head and neck: Anatomic location as a predictor of subclinical tumour extension. J Eur Acad Dermatol Venereol 2023; 37:e101-e103. [PMID: 35972074 DOI: 10.1111/jdv.18524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Accepted: 08/05/2022] [Indexed: 12/15/2022]
Affiliation(s)
- Marcus G Tan
- Division of Dermatology, The University of Ottawa, and The Ottawa Hospital, Ottawa, Ontario, Canada
| | - Ashley M Yu
- Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Jillian Macdonald
- Division of Dermatology, The University of Ottawa, and The Ottawa Hospital, Ottawa, Ontario, Canada
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9
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Li HOY, Pastukhova E, Brandts-Longtin O, Tan MG, Kirchhof MG. YouTube as a source of misinformation on COVID-19 vaccination: a systematic analysis. BMJ Glob Health 2022; 7:bmjgh-2021-008334. [PMID: 35264318 PMCID: PMC8914400 DOI: 10.1136/bmjgh-2021-008334] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 02/16/2022] [Indexed: 12/04/2022] Open
Abstract
Introduction Vaccines for SARS-CoV-2 have been accessible to the public since December 2020. However, only 58.3% of Americans are fully vaccinated as of 5 November 2021. Numerous studies have supported YouTube as a source of both reliable and misleading information during the COVID-19 pandemic. Misinformation regarding the safety and efficacy of COVID-19 vaccines has negatively impacted vaccination intent. To date, the literature lacks a systematic evaluation of YouTube’s content on COVID-19 vaccination using validated scoring tools. The objective of this study was to evaluate the accuracy, usability and quality of the most widely viewed YouTube videos on COVID-19 vaccination. Methods A search on YouTube was performed on 21 July 2021, using keywords ‘COVID-19 vaccine’ on a cleared-cache web browser. Search results were sorted by ‘views’, and the top 150 most-viewed videos were collected and analysed. Duplicate, non-English, non-audiovisual, exceeding 1-hour duration, or videos unrelated to COVID-19 vaccine were excluded. The primary outcome was usability and reliability of videos, analysed using the modified DISCERN (mDISCERN) score, the modified Journal of the American Medical Association (mJAMA) score and the COVID-19 Vaccine Score (CVS). Results Approximately 11% of YouTube’s most viewed videos on COVID-19 vaccines, accounting for 18 million views, contradicted information from the WHO or the Centers for Disease Control and Prevention. Videos containing non-factual information had significantly lower mDISCERN (p<0.001), mJAMA (p<0.01) and CVS (p<0.001) scores compared with videos with factual information. Videos from government sources had higher mJAMA and CVS scores, but averaged three times the ratio of dislikes to likes, while videos containing non-factual information averaged 14 times more likes than dislikes. Conclusion As the COVID-19 pandemic evolves, widespread adoption of vaccination is essential in reducing morbidity, mortality, and returning to some semblance of normalcy. Providing high-quality and engaging health information from reputable sources is essential in addressing vaccine hesitancy.
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Affiliation(s)
- Heidi Oi-Yee Li
- Department of Medicine, Division of Dermatology, University of Ottawa and the Ottawa Hospital, Ottawa, Ontario, Canada.,Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Elena Pastukhova
- Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | | | - Marcus G Tan
- Department of Medicine, Division of Dermatology, University of Ottawa and the Ottawa Hospital, Ottawa, Ontario, Canada.,Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Mark G Kirchhof
- Department of Medicine, Division of Dermatology, University of Ottawa and the Ottawa Hospital, Ottawa, Ontario, Canada .,Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
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10
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Bailey AMJ, Li A, Tan MG, Macdonald J. Prevalence of Misinformation on Tanning Salon Websites: A Systematic Analysis. Dermatol Surg 2022; 48:377-378. [PMID: 35066550 DOI: 10.1097/dss.0000000000003334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
| | - Amy Li
- Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Marcus G Tan
- Division of Dermatology, University of Ottawa, and The Ottawa Hospital, Ottawa, Ontario, Canada
| | - Jillian Macdonald
- Division of Dermatology, University of Ottawa, and The Ottawa Hospital, Ottawa, Ontario, Canada
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11
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Choi B, Tan MG, Gooderham MJ, Beecker J. Reverse koebnerization of primary cutaneous follicle center lymphoma following skin biopsy. JAAD Case Rep 2021; 16:149-151. [PMID: 34621940 PMCID: PMC8484730 DOI: 10.1016/j.jdcr.2021.08.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Affiliation(s)
- Bohmyi Choi
- Faculty of Medicine, University of Ottawa, Ottawa, Canada
| | - Marcus G Tan
- Division of Dermatology, University of Ottawa, and The Ottawa Hospital, Ottawa, Canada
| | | | - Jennifer Beecker
- Faculty of Medicine, University of Ottawa, Ottawa, Canada.,Division of Dermatology, University of Ottawa, and The Ottawa Hospital, Ottawa, Canada.,The Ottawa Hospital Research Institute, Ottawa, Canada
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12
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Tan MG, Kim WB, Jo CE, Nabieva K, Kirshen C, Ortiz AE. Topical treatment for postinflammatory hyperpigmentation: a systematic review. J DERMATOL TREAT 2021; 33:2518-2526. [PMID: 34525885 DOI: 10.1080/09546634.2021.1981814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
BACKGROUND Topical measures are the mainstay treatment for postinflammatory hyperpigmentation (PIH). Numerous studies have assessed the efficacy of topical medications for the treatment of PIH, but few have evaluated the quality of evidence supporting these topical therapies. We performed a systematic review to evaluate the evidence of topical treatments for PIH. METHODS We included English-language studies that evaluated topical medications for PIH. We searched PubMed, MEDLINE, and EMBASE from conception to March 29 2021. We used the modified Grading of Recommendations, Assessment, Development and Evaluation scale (GRADE) scale to assess quality of evidence. RESULTS Forty-seven of 1,224 studies with 1,853 subjects were included. Topical agents with high-quality studies included retinoids, hydroxy acids, corticosteroids, thiamidol, niacinamide and plant-derived products. Sunscreens with SPF30 or greater was recommended in almost every study. Common side effects included desquamation, burning, stinging, dryness, and pruritus. CONCLUSIONS Retinoids, hydroxy acids and broad-spectrum sunscreen were supported by the greatest number of high-quality studies. Ongoing inflammation may be subtle, especially in darker skin phenotypes. Herein, we proposed an evidence-based algorithm for PIH based on the high-quality studies. There is a need to adopt a validated outcome measure for PIH to better compare efficacy between various treatments in future studies.
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Affiliation(s)
- Marcus G Tan
- Division of Dermatology, The University of Ottawa, and The Ottawa Hospital, Ottawa, Canada
| | - Whan B Kim
- Division of Dermatology, The University of Ottawa, and The Ottawa Hospital, Ottawa, Canada
| | - Christine E Jo
- Faculty of Medicine, University of Ottawa, Ottawa, Canada
| | - Karina Nabieva
- Faculty of Medicine, University of Ottawa, Ottawa, Canada
| | - Carly Kirshen
- Division of Dermatology, The University of Ottawa, and The Ottawa Hospital, Ottawa, Canada.,Faculty of Medicine, University of Ottawa, Ottawa, Canada
| | - Arisa E Ortiz
- Department of Dermatology, University of California, San Diego School of Medicine, La Jolla, CA. USA
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13
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Tan MG, Li HO, Pratt MD. Systemic allergic dermatitis to sodium metabisulfite in local anesthetic solution. Contact Dermatitis 2021; 86:120-121. [PMID: 34549447 DOI: 10.1111/cod.13978] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 09/11/2021] [Accepted: 09/19/2021] [Indexed: 11/28/2022]
Affiliation(s)
- Marcus G Tan
- Division of Dermatology, University of Ottawa and The Ottawa Hospital, Ottawa, Ontario, Canada
| | - Heidi O Li
- Division of Dermatology, University of Ottawa and The Ottawa Hospital, Ottawa, Ontario, Canada
| | - Melanie D Pratt
- Division of Dermatology, University of Ottawa and The Ottawa Hospital, Ottawa, Ontario, Canada
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14
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Bailey AJM, Li HOY, Tan MG, Cheng W, Dover JS. Microneedling as an adjuvant to topical therapies for melasma: A systematic review and meta-analysis. J Am Acad Dermatol 2021; 86:797-810. [PMID: 33857549 DOI: 10.1016/j.jaad.2021.03.116] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 03/12/2021] [Accepted: 03/26/2021] [Indexed: 11/18/2022]
Abstract
BACKGROUND Microneedling as an adjuvant to topical medications has shown promising but variable results in the treatment of melasma. OBJECTIVE To conduct a systematic review and meta-analysis on the efficacy of microneedling as an adjuvant to topical therapies for the treatment of melasma. METHODS This study followed PRISMA guidelines. All comparative, prospective studies on the use of topical interventions with microneedling for the treatment of melasma were included. Studies involving radiofrequency microneedling were excluded. RESULTS Twelve eligible studies comprising 459 patients from 7 different countries were included. Topical therapies included topical tranexamic acid, vitamin C, platelet-rich plasma, non-hydroquinone-based depigmentation serums, and hydroquinone-based depigmenting agents. Topical therapy with microneedling improved melasma severity with a large effect (standardized mean difference >0.8) beyond 8 weeks, with best results seen at 12 weeks. Compared to topical therapy alone, topical therapy with microneedling resulted in an additional improvement in melasma severity with a moderate effect at 8 weeks and a large effect at 12-16 weeks. Microneedling was well tolerated across studies, with no serious adverse events reported. LIMITATIONS Heterogeneity in study designs did not allow for a comparison of the efficacy of various topical therapies with microneedling. CONCLUSION Microneedling is useful adjuvant to topical therapies for the treatment of melasma.
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Affiliation(s)
| | - Heidi Oi-Yee Li
- Faculty of Medicine, The University of Ottawa, Ottawa, Ontario, Canada
| | - Marcus G Tan
- Faculty of Medicine, The University of Ottawa, Ottawa, Ontario, Canada; Division of Dermatology, The Ottawa Hospital, Ottawa, Ontario, Canada
| | - Wei Cheng
- Department of Biostatistics, Yale School of Public Health, New Haven, Connecticut
| | - Jeffrey S Dover
- SkinCare Physicians, Chestnut Hill, Massachusetts; Department of Dermatology, Yale University School of Medicine, New Haven, Connecticut; Brown Medical School, Providence, Rhode Island.
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15
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Tan MG, Kirchhof MG. Éruption papulosquameuse avec symptômes oculaires dus à la syphilis. CMAJ 2021; 193:E321-E322. [PMID: 33649176 PMCID: PMC8034309 DOI: 10.1503/cmaj.200820-f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Affiliation(s)
- Marcus G Tan
- Division de dermatologie, Faculté de médecine de l'Université d'Ottawa; Hôpital d'Ottawa, Ottawa, Ont
| | - Mark G Kirchhof
- Division de dermatologie, Faculté de médecine de l'Université d'Ottawa; Hôpital d'Ottawa, Ottawa, Ont.
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16
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Tan MG, Kirchhof MG. Papulosquamous eruption with ocular symptoms caused by syphilis. CMAJ 2020; 192:E1727. [DOI: 10.1503/cmaj.200820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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17
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Joseph Bailey AM, Oi-Yee Li H, Tan MG, Kirchhof MG. Hidradenitis suppurativa and major adverse cardiac events: A systematic review and meta-analysis. J Am Acad Dermatol 2020; 84:844-848. [PMID: 33038472 DOI: 10.1016/j.jaad.2020.10.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 09/28/2020] [Accepted: 10/05/2020] [Indexed: 11/16/2022]
Affiliation(s)
| | - Heidi Oi-Yee Li
- Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Marcus G Tan
- Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada; Division of Dermatology, The Ottawa Hospital, Ottawa, Ontario, Canada
| | - Mark G Kirchhof
- Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada; Division of Dermatology, The Ottawa Hospital, Ottawa, Ontario, Canada.
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18
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Tan MG, Beecker J. Chickenpox in an elderly man. Can Fam Physician 2020; 66:e213-e215. [PMID: 32817048 PMCID: PMC7430786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Affiliation(s)
- Marcus G Tan
- Dermatology resident in the Division of Dermatology at The Ottawa Hospital in Ontario
| | - Jennifer Beecker
- Associate Professor of Dermatology at the University of Ottawa and a dermatologist in the Division of Dermatology at The Ottawa Hospital
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19
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Tan MG, Pratt MD, Burns BF, Glassman SJ. Baboon syndrome from mercury showing leukocytoclastic vasculitis on biopsy. Contact Dermatitis 2020; 83:415-417. [PMID: 32462678 DOI: 10.1111/cod.13625] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 05/21/2020] [Accepted: 05/25/2020] [Indexed: 11/27/2022]
Affiliation(s)
- Marcus G Tan
- Division of Dermatology, The University of Ottawa, and The Ottawa Hospital, Ottawa, Ontario, Canada
| | - Melanie D Pratt
- Division of Dermatology, The University of Ottawa, and The Ottawa Hospital, Ottawa, Ontario, Canada
| | - Bruce F Burns
- Department of Anatomical Pathology, The University of Ottawa, and The Ottawa Hospital, Ottawa, Ontario, Canada
| | - Steven J Glassman
- Division of Dermatology, The University of Ottawa, and The Ottawa Hospital, Ottawa, Ontario, Canada
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Chew MH, Chau KC, Koh FH, Ng A, Ng SP, Ng SF, Tan MG, Ong SGK, Teo LM, Ong BC. Safe operating room protocols during the COVID-19 pandemic. Br J Surg 2020; 107:e292-e293. [PMID: 32506427 PMCID: PMC7300865 DOI: 10.1002/bjs.11721] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 04/30/2020] [Indexed: 12/23/2022]
Affiliation(s)
- M H Chew
- Department of General Surgery, Anaesthesiology, Intensive Care, and Operating Theatre Services, Sengkang General Hospital, Singapore
| | - K C Chau
- Department of General Surgery, Anaesthesiology, Intensive Care, and Operating Theatre Services, Sengkang General Hospital, Singapore
| | - F H Koh
- Department of General Surgery, Anaesthesiology, Intensive Care, and Operating Theatre Services, Sengkang General Hospital, Singapore
| | - A Ng
- Department of General Surgery, Anaesthesiology, Intensive Care, and Operating Theatre Services, Sengkang General Hospital, Singapore
| | - S P Ng
- Department of General Surgery, Anaesthesiology, Intensive Care, and Operating Theatre Services, Sengkang General Hospital, Singapore
| | - S F Ng
- Department of General Surgery, Anaesthesiology, Intensive Care, and Operating Theatre Services, Sengkang General Hospital, Singapore
| | - M G Tan
- Department of General Surgery, Anaesthesiology, Intensive Care, and Operating Theatre Services, Sengkang General Hospital, Singapore
| | - S G K Ong
- Department of General Surgery, Anaesthesiology, Intensive Care, and Operating Theatre Services, Sengkang General Hospital, Singapore
| | - L M Teo
- Department of General Surgery, Anaesthesiology, Intensive Care, and Operating Theatre Services, Sengkang General Hospital, Singapore
| | - B C Ong
- Department of General Surgery, Anaesthesiology, Intensive Care, and Operating Theatre Services, Sengkang General Hospital, Singapore
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Tan MG, Worley B, Kim WB, ten Hove M, Beecker J. Drug-Induced Intracranial Hypertension: A Systematic Review and Critical Assessment of Drug-Induced Causes. Am J Clin Dermatol 2020; 21:163-172. [PMID: 31741184 DOI: 10.1007/s40257-019-00485-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
BACKGROUND Idiopathic intracranial hypertension (IIH) is a condition with increased intracranial pressure of unknown etiology. Its presenting symptoms include persistent headache, pulsatile tinnitus, and visual obscuration. It tends to occur in obese women of childbearing age, and its greatest risk is irreversible loss of vision. Some of the commonly used medications in dermatology, especially those for acne vulgaris, have been associated with IIH. However, the creation of specific risk categories for drugs as a guide for clinicians has never been performed. OBJECTIVE The aim of this study was to critically assess all published cases of IIH and identify high-risk drugs associated with drug-induced intracranial hypertension (DIIH), to assist dermatologists and other physicians with patient education and monitoring of symptoms of secondary intracranial hypertension. METHODS MEDLINE, EMBASE, and Cochrane Review Databases were searched for all cases of IIH thought to be drug-related between January 1900 and June 2019. A total of 5117 articles were identified, and 235 articles were found to be relevant. All cases were assessed to satisfy the modified Dandy criteria for diagnosis of IIH, and the likelihood of each case being a 'definite' adverse drug reaction (ADR) was determined using the Koh algorithm for ADR. An association category (from weakly associated [Category I] to strongly associated [Category V]) was assigned based on the number of cases meeting these two criteria. RESULTS There were 259 verifiable cases of DIIH. Vitamin A derivatives, tetracycline-class antibiotics, recombinant growth hormone, and lithium were found to be most strongly associated with DIIH (Categories IV and V). Corticosteroids were moderately associated with DIIH (Category III). Drugs that were weakly associated with DIIH (Categories I and II) include cyclosporine, progestin-only contraceptives, combined oral contraceptives, second- and third-generation fluoroquinolones, sulfenazone, gonadotropin-releasing hormones and luteinizing hormone-releasing hormone agonist, nalidixic acid, amiodarone, stanozolol, danazol, divalproic acid, sulfasalazine, ketoconazole, and ustekinumab. CONCLUSION We suggest using the term 'drug-induced intracranial hypertension' (DIIH) and propose a set of diagnostic criteria for DIIH. Our review attempts to identify DIIH-associated drugs based on a strict diagnostic and drug-causality algorithm, then stratify them into appropriate risks categories. This may ultimately assist physicians in counselling patients about the risk of DIIH when prescribing medications and recognizing this uncommon yet sight-threatening condition.
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Affiliation(s)
- Marcus G. Tan
- Division of Dermatology, University of Ottawa and The Ottawa Hospital, Ottawa, Ontario
| | - Bruce F. Burns
- Division of Anatomical Pathology, University of Ottawa and The Ottawa Hospital, Ottawa, Ontario
| | - Steven J. Glassman
- Division of Dermatology, University of Ottawa and The Ottawa Hospital, Ottawa, Ontario
- Correspondence to: Steven J. Glassman, MD, The Ottawa Hospital, Division of Dermatology, 737 Parkdale Avenue, 4 Floor, Ottawa, Ontario, K1Y 1J8, Canada.
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Tan MG, Isaranuwatchai W, DeLyzer T, Butler K, Hofer SOP, O'Neill AC, Zhong T. A cost-effectiveness analysis of DIEP vs free MS-TRAM flap for microsurgical breast reconstruction. J Surg Oncol 2018; 119:388-396. [DOI: 10.1002/jso.25325] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Accepted: 11/19/2018] [Indexed: 11/10/2022]
Affiliation(s)
- Marcus G. Tan
- Department of Undergraduate Medical Education, Faculty of Medicine, University of Toronto; Toronto Ontario Canada
| | - Wanrudee Isaranuwatchai
- Centre for Excellence in Economic Analysis Research, St. Michael's Hospital; Toronto Ontario Canada
- Institute of Health Policy, Management and Evaluation, University of Toronto; Toronto Ontario Canada
| | - Tanya DeLyzer
- Division of Plastic and Reconstructive Surgery; University Health Network; Toronto Ontario Canada
| | - Kate Butler
- Division of Plastic and Reconstructive Surgery; University Health Network; Toronto Ontario Canada
| | - Stefan O. P. Hofer
- Division of Plastic and Reconstructive Surgery; University Health Network; Toronto Ontario Canada
| | - Anne C. O'Neill
- Division of Plastic and Reconstructive Surgery; University Health Network; Toronto Ontario Canada
| | - Toni Zhong
- Division of Plastic and Reconstructive Surgery; University Health Network; Toronto Ontario Canada
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Abstract
BACKGROUND/OBJECTIVES Excessive sun exposure during childhood is a risk factor for skin cancer. This study aimed to compare the frequency of ideal sun protection use between parents with lighter- and darker-skinned children and explore their attitudes and beliefs on sun safety and their choice of sun protection. METHODS Parents of children aged 6 months to 6 years completed self-administered questionnaires about sun protection practices for their children. Parents assessed their child's Fitzpatrick phototype and were divided into lighter- (Fitzpatrick phototype I-III) and darker-skinned (Fitzpatrick phototype IV-VI) groups. Sun safety guidelines from the Canadian Dermatology Association were used to qualify ideal sun protection. RESULTS A total of 183 parents were included. Overall, 31 parents (17%) used ideal sun protection for their children. As their children grew older, parents were less likely to use ideal sun protection (odds ratio = 0.69, 95% confidence interval = 0.53-0.90). Parents in the lighter-skinned group were more likely to use ideal sun protection for their children (odds ratio = 7.4, 95% confidence interval = 2.7-20.1), believe that sun exposure was harmful (odds ratio = 17.2, 95% confidence interval = 4.0-74.9), and perceive value in sun protection (odds ratio = 11.4, 95% confidence interval = 3.3-39.0); the darker-skinned group believed that darker skin tones provided more sun protection (odds ratio = 12.4, 95% confidence interval = 6.1-25.4). CONCLUSION Ideal parental sun protection efforts are overall low, particularly in parents of darker-skinned children. The identified attitudes toward and beliefs about sun safety may aid in delivery of future sun protection interventions, especially in multiracial populations.
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Affiliation(s)
- Marcus G Tan
- Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Shudeshna Nag
- Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Miriam Weinstein
- Division of Pediatric Medicine, Section of Dermatology, The Hospital for Sick Children, Toronto, Ontario, Canada
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Mehdizadeh A, Alavi A, Alhusayen R, Bauer B, Bechara FG, Bourcier M, Brassard A, Djamei V, Dutz J, George R, Ghias M, Gooderham M, Hamzavi I, Hoffman LK, Hou A, Hu H, Kimball AB, Kirchhof M, Kryzskaya D, Liy Wong MDC, Lowes MA, Lynde CW, McLellen C, Prens E, Prens L, Rogalska T, Sibbald RG, Sisic M, Tan MG, Wong DD. Proceeding report of the Symposium on Hidradenitis Suppurativa Advances (SHSA). Exp Dermatol 2017; 27:104-112. [DOI: 10.1111/exd.13445] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/29/2017] [Indexed: 11/28/2022]
Affiliation(s)
- Ali Mehdizadeh
- University of Toronto Dalla Lana School of Public Health; Toronto ON Canada
| | | | | | - Boris Bauer
- Universitatsklinikum Wurzburg; Wurzburg Germany
| | | | | | - Alain Brassard
- Department of Dermatology; University of Alberta; Edmonton AB Canada
| | - Vahid Djamei
- Dermatology, Information Systems (Business Informatics); Information Science University of Zürich; Zürich Switzerland
| | - Jan Dutz
- Department of Dermatology & Skin Science; University of British Columbia; Vancouver BC Canada
| | - Ralph George
- Division of General Surgery; University of Toronto; Toronto ON Canada
| | - Mondana Ghias
- Montefiore Hospital and Medical Center; Bronx NY USA
| | | | | | | | - Angela Hou
- New York University Langone Medical Center; NewYork; NY USA
| | - Howard Hu
- University of Toronto Dalla Lana School of Public Health; Toronto ON Canada
| | | | - Mark Kirchhof
- Division of Dermatology; Department of Medicine; University of Ottawa; Ottawa ON Canada
| | - Darya Kryzskaya
- Division of Pediatric Dermatology; Montreal Children's Hospital; McGill University Health Center; Montreal QC Canada
| | | | | | - Charles W. Lynde
- Department of Medicine; University of Toronto; Toronto ON Canada
| | | | - Errol Prens
- Dermatology; Erasmus MC; Rotterdam The Netherlands
| | | | - Tetyana Rogalska
- Department of Family Medicine; University of Ottawa; Ottawa ON Canada
| | | | - Mia Sisic
- University of Windsor; Windsor ON Canada
| | - Marcus G. Tan
- Department of Medicine; University of Toronto; Toronto ON Canada
| | - Dennis D. Wong
- Department of Medicine; University of Toronto; Toronto ON Canada
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Cembrowski AR, Tan MG, Thomson JD, Frederickson ME. Ants and Ant Scent Reduce Bumblebee Pollination of Artificial Flowers. Am Nat 2014; 183:133-9. [DOI: 10.1086/674101] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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27
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Tan MG, Zhang GL, Li XL, Zhang YX, Yue WS, Chen JM, Wang YS, Li AG, Li Y, Zhang YM, Shan ZC. Comprehensive study of lead pollution in Shanghai by multiple techniques. Anal Chem 2007; 78:8044-50. [PMID: 17134138 DOI: 10.1021/ac061365q] [Citation(s) in RCA: 125] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Aerosol samples of PM10 particulates were examined with particle-induced X-ray emission (PIXE and micro-PIXE ), inductively coupled plasma-mass spectrometry, and X-ray absorption fine structures (XAFS) to investigate atmospheric Pb concentrations and its chemical species and to decide the source assignment. From the elemental analyses, lead concentrations were averaged at 369 and 237 ng.m-3 in aerosol samples of PM10 collected from 19 monitor sites in Shanghai in the winter of 2002 and 2003, respectively. The XAFS results show that major chemical forms of the lead particulates are probably PbCl2, PbSO4, and PbO. A calculation of isotope ratio and chemical mass balance of the PM10 samples revealed that the atmospheric lead particulates in Shanghai in the two periods were mainly from coal combustors, iron and steel plants, and automobile exhausts, with coal combustion dominating the lead pollution after the phasing out of leaded gasoline in 1997 in Shanghai.
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Affiliation(s)
- M G Tan
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
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28
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Tan EK, Zhao Y, Skipper L, Tan MG, Di Fonzo A, Sun L, Fook-Chong S, Tang S, Chua E, Yuen Y, Tan L, Pavanni R, Wong MC, Kolatkar P, Lu CS, Bonifati V, Liu JJ. The LRRK2 Gly2385Arg variant is associated with Parkinson’s disease: genetic and functional evidence. Hum Genet 2006; 120:857-63. [PMID: 17019612 DOI: 10.1007/s00439-006-0268-0] [Citation(s) in RCA: 127] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2006] [Accepted: 09/11/2006] [Indexed: 10/24/2022]
Abstract
Evidence of LRRK2 haplotypes associated with Parkinson's disease (PD) risk was recently found in the Chinese population from Singapore, and a common LRRK2 missense variant, Gly2385Arg, was independently detected as a putative risk factor for PD in the Chinese population from Taiwan. To test the association between the Gly2385Arg variant in a large case-control sample of Chinese ethnicity from Singapore, and to perform functional studies of the wild type and Gly2385Arg LRRK2 protein in human cell lines. In a case-control study involving 989 Chinese subjects, the frequency of the heterozygous Gly2385Arg genotype was higher in PD compared to controls (7.3 vs. 3.6%, odds ratio = 2.1, 95% CI: 1.1-3.9, P = 0.014); these values yield an estimated population attributable risk (PAR) of approximately 4%. In a multivariate logistic regression analysis with the disease group (PD vs. controls) as the dependent variable and the genotype as an independent factor with adjustments made for the effect of age and gender, the heterozygous Gly2385Arg genotype remained associated with an increased risk of PD compared to wild type genotype (odds ratio = 2.67, 95% CI: 1.43-4.99, P = 0.002). The glycine at position 2385 is a candidate site for N-myristoylation, and the Gly2385Arg variant replaces the hydrophobic glycine with the hydrophilic arginine, and increases the net positive charge of the LRRK2 WD40 domain. In transfection studies, we demonstrated that both the wild type and Gly2385Arg variant LRRK2 protein localize to the cytoplasm and form aggregates. However, under condition of oxidative stress, the Gly2385Arg variant was more toxic and associated with a higher rate of apoptosis. Our study lends support to the contention that the Gly2385Arg is a common risk factor for PD in the Chinese population. Our bioinformatics and in-vitro studies also suggest that the Gly2385Arg variant is biologically relevant and it might act through pro-apoptotic mechanisms.
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Affiliation(s)
- E K Tan
- Department of Neurology, Singapore General Hospital, Outram Road, Singapore, Singapore
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Lin VC, Aw SE, Ng EH, Ng EH, Tan MG. Demonstration of mixed properties of RU486 in progesterone receptor (PR)-transfected MDA-MB-231 cells: a model for studying the functions of progesterone analogues. Br J Cancer 2001; 85:1978-86. [PMID: 11747343 PMCID: PMC2364017 DOI: 10.1054/bjoc.2001.2167] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Progesterone antagonist RU486 (mifepristone) has been implicated for many anti-neoplastic and obstetrical applications. But the compound has demonstrated undesired agonist-like effect depending on cell, tissue and species studied. Using PR-transfected breast cancer cells MDA-MB-231, this report describes the similarities and differences between progesterone- and RU486-mediated effects on cell growth, cell differentiation and, at the molecular level, on the activation of p44/p42 MAP kinases (MAPK). Like progesterone, RU486 inhibited cells growth by arresting the cells in G0/G1 phase of the cell cycle. In contrast to progesterone that induced cell spreading, RU486 induced a multipolar, stellate morphology. RU486-treated cells showed no increase of stress fibers, nor was there any increase of focal adhesions as progesterone-treated cells did. Furthermore, despite of the fact that both compounds inhibited cell growth, RU486 significantly stimulated the activation of p44/p42 MAP kinases whereas progesterone markedly inhibited the activation. Nonetheless, the effects of RU486 were PR-mediated and RU486 was able to antagonize the effect of progesterone on cell growth and focal adhesion. In conclusion, RU486 can act not only as a progesterone antagonist, a progesterone agonist but also induced morphological and molecular changes that were distinct from progesterone-mediated effects in PR-transfected MDA-MB-231 cells. The non-progesterone-like effect of RU486 may be mediated through a pathway that is different from the progesterone-mediated pathway, or it is the result of a blockade of certain critical step(s) in the progesterone-mediated pathway. In any case, undesired side effects of antiprogestin may create clinical complications. PR-transfected MDA-MB-231 breast cancer cells provide a model for studying the functions of progesterone analogues.
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Affiliation(s)
- V C Lin
- Department of Clinical Research, Singapore General Hospital, Republic of Singapore 169608
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Lin VC, Ng EH, Aw SE, Tan MG, Ng EH, Bay BH. Progesterone induces focal adhesion in breast cancer cells MDA-MB-231 transfected with progesterone receptor complementary DNA. Mol Endocrinol 2000; 14:348-58. [PMID: 10707953 DOI: 10.1210/mend.14.3.0426] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Since the effects of progesterone are mediated mainly via estrogen-dependent progesterone receptor (PR), the expression of the effects of progesterone may be masked or overridden by the influence of estrogen under conditions in which priming with estrogens is required. We have established a PR-positive but estrogen receptor-alpha (ER-alpha) negative breast cancer cell model by transfecting PR cDNA into ER-alpha- and PR-negative MDA-MB-231 cells in order that the functions of progesterone can be studied independently of estrogens. We have demonstrated using this model that progesterone markedly inhibited cell growth. We have also discovered that progesterone induced remarkable changes in cell morphology and specific adhesion structures. Progesterone-treated cells became considerably more flattened and well spread than vehicle-treated control cells. This was associated with a striking increase of stress fibers, both in number and diameter, and increased focal contacts as shown by the staining of focal adhesion proteins paxillin and talin. There were also distinct increases in tyrosine phosphorylation of focal adhesion protein paxillin and focal adhesion kinase in association with increased focal adhesion. The staining of tyrosine-phosphorylated proteins was concentrated at focal adhesions in progesterone-treated cells. More interestingly, monoclonal antibody (Ab) to beta1 integrin was able to inhibit progesterone-induced cell spreading and formation of actin cytoskeleton. To our knowledge, this is the first report describing a direct effect of progesterone in inducing spreading and adhesion of breast cancer cells, and beta1-integrin appeared to play an essential role in the effect. It is known that the initial step of tumor metastasis is the breakaway of tumor cells from primary tumor mass when they lose the ability to attach. Hence, progesterone-induced cell spreading and adhesion may have significant implications in tumor metastasis.
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Affiliation(s)
- V C Lin
- Department of Clinical Research, Singapore General Hospital, Republic of Singapore.
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Lin VC, Ng EH, Aw SE, Tan MG, Ng EH, Chan VS, Ho GH. Progestins inhibit the growth of MDA-MB-231 cells transfected with progesterone receptor complementary DNA. Clin Cancer Res 1999; 5:395-403. [PMID: 10037189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
Because progesterone exerts its effects mainly via estrogen-dependent progesterone receptor (PgR), the expression of progesterone's effects may be overshadowed by the priming effect of estrogen. PgR expression vectors were transfected into estrogen receptor (ER)-alpha and PgR-negative breast cancer cells MDA-MB-231; thus the functions of progesterone could be studied independent of estrogens and ERs. Eight stable transfectant clones expressing both PgR isoform A and B were studied for their growth response to progesterone and its analogues. Although progesterone had no effect on growth in the control transfectant, the hormone markedly inhibited DNA synthesis and cell growth in all of the PgR-transfectants dose-dependently from 10(-12)-10(-6) M. This growth inhibition was associated with an arrest of cells in the G0/G1 phase of the cell cycle. Progestins medroxyprogesterone acetate, Org2058, and R5020 also strongly inhibited DNA synthesis, and their doses required for maximal inhibition of 60-70% were 10(-17) M, 10(-13) M, and 10(-7) M, respectively. Antiprogestin ZK98299 alone had no effect, but the compound was capable of counteracting the inhibitory effect of progesterone. In contrast, RU486 inhibited DNA synthesis, and it showed no further effects when it was used concurrently with progesterone. These results indicate that progestins are per se antiproliferative via a PgR-mediated mechanism in breast cancer cells. More importantly, we have shown that progestins may exert effective inhibitory control over the cell growth if the PgR expression is reactivated in ER- and PgR-negative breast cancer cells.
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Affiliation(s)
- V C Lin
- Department of Clinical Research, Ministry of Health, Singapore General Hospital, Republic of Singapore.
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Zhuang GS, Wang YS, Tan MG, Zhi M, Pan WQ, Cheng YD. Preliminary study of the distribution of the toxic elements As, Cd, and Hg in human hair and tissues by RNAA. Biol Trace Elem Res 1990; 26-27:729-36. [PMID: 1704781 DOI: 10.1007/bf02992729] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
In order to study the relationships between trace element concentrations of hair and internal body burdens, a radiochemical NAA technique has been used for determination of the elements As, Cd, and Hg in autopsy samples of liver, kidney-cortex, lung, and hair from 24 male persons who died by accident. High significant positive correlations were observed between the As concentration in hair and in kidney-cortex, and between Cd and Zn concentrations in kidney-cortex. The contents of Cd, both for lung and kidney-cortex, were related to the smoking habits of the subjects.
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Affiliation(s)
- G S Zhuang
- Shanghai Institute of Nuclear Research, Academia Sinica, Shanghai, People's Republic of China
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Abstract
The correlations of essential element Se between human hair and kidney-cortex, liver, and lung from the same subjects were investigated by instrumental neutron activation analysis, using the reaction 76Se (n, gamma) 77mSe, for 24 Chinese autopsies. The concentration of Se is higher in kidney-cortex (2.04-5.36 mg/kg) than in liver (0.73-2.29), lung (0.50-1.85), and hair (0.37-1.43). It is important to know that there are significant relationships of Se concentration between hair and the other three internal organs. The correlation coefficient by linear regression analysis are 0.639, 0.570, and 0.635 for liver, lung, and kidney-cortex, respectively; and the P values are all less than 0.01 for the three tissues.
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Affiliation(s)
- Y D Cheng
- Shanghai Institute of Nuclear Research, People's Republic of China
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Tan MG. [The dexamethasone test and mania]. Zhonghua Shen Jing Jing Shen Ke Za Zhi 1985; 18:284-6. [PMID: 3833513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Zhu W, Li WY, Kuang AK, Tan MG, Qin JF, Sheng KL, Chen ZX, Li MQ. A preliminary study on serum trace elements in "Yin-deficiency" and "Yang-deficiency" patients. Application of the PIXE analysis in medical science. J TRADIT CHIN MED 1983; 3:145-50. [PMID: 6555450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2023]
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36
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Pin L, Tan MG. Clinical experience with hyperosmolar non-ketotic diabetic coma. Singapore Med J 1975; 16:147-9. [PMID: 1162393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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