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Lai FTT, Liu W, Hu Y, Wei C, Chu RYK, Lum DH, Leung JCN, Cheng FWT, Chui CSL, Li X, Wan EYF, Wong CKH, Cheung CL, Chan EWY, Hung IFN, Wong ICK. Elevated risk of multimorbidity post-COVID-19 infection: protective effect of vaccination. QJM 2024; 117:125-132. [PMID: 37824396 DOI: 10.1093/qjmed/hcad236] [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] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2023] [Revised: 10/05/2023] [Indexed: 10/14/2023] Open
Abstract
BACKGROUND It is unclear how the coronavirus disease 2019 (Covid-19) pandemic has affected multimorbidity incidence among those with one pre-existing chronic condition, as well as how vaccination could modify this association. AIM To examine the association of Covid-19 infection with multimorbidity incidence among people with one pre-existing chronic condition, including those with prior vaccination. DESIGN Nested case-control study. METHODS We conducted a territory-wide nested case-control study with incidence density sampling using Hong Kong electronic health records from public healthcare facilities and mandatory Covid-19 reports. People with one listed chronic condition (based on a list of 30) who developed multimorbidity during 1 January 2020-15 November 2022 were selected as case participants and randomly matched with up to 10 people of the same age, sex and with the same first chronic condition without having developed multimorbidity at that point. Conditional logistic regression was used to estimate adjusted odds ratios (aORs) of multimorbidity. RESULTS In total, 127 744 case participants were matched with 1 230 636 control participants. Adjusted analysis showed that there were 28%-increased odds of multimorbidity following Covid-19 [confidence interval (CI) 22% to 36%] but only 3% (non-significant) with prior full vaccination with BNT162b2 or CoronaVac (95% CI -2% to 7%). Similar associations were observed in men, women, older people aged 65 or more, and people aged 64 or younger. CONCLUSIONS We found a significantly elevated risk of multimorbidity following a Covid-19 episode among people with one pre-existing chronic condition. Full vaccination significantly reduced this risk increase.
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Affiliation(s)
- F T T Lai
- Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, Centre for Safe Medication Practice and Research, The University of Hong Kong, Pok Fu Lam, Hong Kong SAR, China
- Department of Family Medicine and Primary Care, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pok Fu Lam, Hong Kong SAR, China
- Laboratory of Data Discovery for Health (D24H), Hong Kong Science Park, Sha Tin, Hong Kong SAR, China
| | - W Liu
- Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, Centre for Safe Medication Practice and Research, The University of Hong Kong, Pok Fu Lam, Hong Kong SAR, China
| | - Y Hu
- Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, Centre for Safe Medication Practice and Research, The University of Hong Kong, Pok Fu Lam, Hong Kong SAR, China
| | - C Wei
- Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, Centre for Safe Medication Practice and Research, The University of Hong Kong, Pok Fu Lam, Hong Kong SAR, China
| | - R Y K Chu
- Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, Centre for Safe Medication Practice and Research, The University of Hong Kong, Pok Fu Lam, Hong Kong SAR, China
| | - D H Lum
- Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, Centre for Safe Medication Practice and Research, The University of Hong Kong, Pok Fu Lam, Hong Kong SAR, China
| | - J C N Leung
- Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, Centre for Safe Medication Practice and Research, The University of Hong Kong, Pok Fu Lam, Hong Kong SAR, China
| | - F W T Cheng
- Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, Centre for Safe Medication Practice and Research, The University of Hong Kong, Pok Fu Lam, Hong Kong SAR, China
| | - C S L Chui
- Laboratory of Data Discovery for Health (D24H), Hong Kong Science Park, Sha Tin, Hong Kong SAR, China
- School of Nursing, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pok Fu Lam, Hong Kong SAR, China
- School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pok Fu Lam, Hong Kong SAR, China
| | - X Li
- Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, Centre for Safe Medication Practice and Research, The University of Hong Kong, Pok Fu Lam, Hong Kong SAR, China
- Laboratory of Data Discovery for Health (D24H), Hong Kong Science Park, Sha Tin, Hong Kong SAR, China
- Department of Medicine, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pok Fu Lam, Hong Kong SAR, China
| | - E Y F Wan
- Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, Centre for Safe Medication Practice and Research, The University of Hong Kong, Pok Fu Lam, Hong Kong SAR, China
- Department of Family Medicine and Primary Care, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pok Fu Lam, Hong Kong SAR, China
- Laboratory of Data Discovery for Health (D24H), Hong Kong Science Park, Sha Tin, Hong Kong SAR, China
| | - C K H Wong
- Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, Centre for Safe Medication Practice and Research, The University of Hong Kong, Pok Fu Lam, Hong Kong SAR, China
- Department of Family Medicine and Primary Care, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pok Fu Lam, Hong Kong SAR, China
- Laboratory of Data Discovery for Health (D24H), Hong Kong Science Park, Sha Tin, Hong Kong SAR, China
| | - C L Cheung
- Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, Centre for Safe Medication Practice and Research, The University of Hong Kong, Pok Fu Lam, Hong Kong SAR, China
- Laboratory of Data Discovery for Health (D24H), Hong Kong Science Park, Sha Tin, Hong Kong SAR, China
| | - E W Y Chan
- Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, Centre for Safe Medication Practice and Research, The University of Hong Kong, Pok Fu Lam, Hong Kong SAR, China
- Laboratory of Data Discovery for Health (D24H), Hong Kong Science Park, Sha Tin, Hong Kong SAR, China
| | - I F N Hung
- Department of Medicine, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pok Fu Lam, Hong Kong SAR, China
| | - I C K Wong
- Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, Centre for Safe Medication Practice and Research, The University of Hong Kong, Pok Fu Lam, Hong Kong SAR, China
- Laboratory of Data Discovery for Health (D24H), Hong Kong Science Park, Sha Tin, Hong Kong SAR, China
- Aston Pharmacy School, Aston University, Birmingham, England, UK
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Liang XP, Or CY, Tsoi MF, Cheung CL, Cheung BMY. Prevalence of metabolic syndrome in the United States National Health and Nutrition Examination Survey (nhanes) 2011–2018. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.2420] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
Metabolic syndrome (MetS) is a cluster of risk factors presaging the development of cardiovascular disease and diabetes. It is a risk factor for severe coronavirus disease 2019 (COVID-19).
Purpose
To estimate the prevalence of MetS in the US National Health and Nutrition Examination Survey (NHANES) 2011–2018.
Methods
This cohort study included 22370 eligible participants aged ≥20 years from the NHANES 2011–2018. MetS was defined as the presence of at least three of these components: central obesity, reduced high-density lipoprotein, elevated triglycerides, elevated blood pressure and elevated fasting blood glucose. The prevalence of MetS was estimated taking into account the complex sampling. The time trend was evaluated using logistic regression. Annual percentage changes (APC) were measured trend in MetS prevalence.
Results
The prevalence of MetS was 36.2% (95% CI, 32.3–40.3), 34.8% (95% CI, 32.3–37.4), 39.9% (95% CI, 36.6–43.2) and 38.3% (95% CI, 35.3–41.3) in 2011–2, 2013–4, 2015–6, 2017–8, respectively (P for trend = 0.08). Among the MetS components, the prevalence of elevated glucose increased from 48.7% (95% CI, 45.9–51.5) in 2011–2 to 64.3% (95% CI, 61.0–67.4) in 2017–8 [P for trend <0.001; APC=11.7, (95% CI, 3.5–21.0)]. The prevalence of MetS in non-Hispanic Asian increased from 21.8% (95% CI, 16.7–28.0) in 2011–2 to 31.2% (95% CI, 27.4–35.3) in 2017–8 [P for trend <0.001; APC=14.6, (95% CI, 2.5–34.8)].
Conclusions
The prevalence of MetS remained stable during 2011 to 2018. Lifestyle modification is needed, especially among non-Hispanic Asians to prevent the metabolic syndrome and the associated risks of diabetes and cardiovascular disease.
Funding Acknowledgement
Type of funding sources: None.
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Affiliation(s)
- X P Liang
- The University of Hong Kong, Division of Clinical Pharmacology and Therapeutics, Department of Medicine, Hong Kong, Hong Kong
| | - C Y Or
- The University of Hong Kong, Division of Clinical Pharmacology and Therapeutics, Department of Medicine, Hong Kong, Hong Kong
| | - M F Tsoi
- The University of Hong Kong, Division of Clinical Pharmacology and Therapeutics, Department of Medicine, Hong Kong, Hong Kong
| | - C L Cheung
- The University of Hong Kong, Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, Hong Kong, Hong Kong
| | - B M Y Cheung
- The University of Hong Kong, Division of Clinical Pharmacology and Therapeutics, Department of Medicine, Hong Kong, Hong Kong
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Kwok TCY, Law SW, Leung EMF, Choy DTK, Lam PMS, Leung JCS, Wong SH, Ip TP, Cheung CL. Hip fractures are preventable: a proposal for osteoporosis screening and fall prevention in older people. Hong Kong Med J 2021; 26:227-235. [PMID: 32554817 DOI: 10.12809/hkmj198337] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Osteoporosis is highly prevalent but underdiagnosed and undertreated in Hong Kong. Fragility fractures associated with osteoporosis often result in loss of independence and increased mortality for home-dwelling patients, imposing a high socio-economic burden on society. This issue requires urgent attention given the rapid growth of the elderly population in Hong Kong by approximately 4.3% each year. To address this situation, a group of experts convened to discuss practical ways to reduce the burden of fractures and formulated three recommendations: first, all men (aged ≥70 years) and women (aged ≥65 years) should receive universal dual-energy X-ray absorptiometry assessment for osteoporosis. Second, all men (aged ≥70 years) and women (aged ≥65 years) with a fracture-risk assessment-derived 10-year risk (hip fracture with bone mineral density) ≥3% should receive ≥3 years of anti-osteoporotic treatment. Third, comprehensive structured assessment (including dual-energy X-ray absorptiometry) should be conducted in older patients with a history of falling. By implementing these recommendations, we estimate that we could prevent 5234 hip fractures in 10 years, an annual incidence reduction of approximately 7%, and save HK$425 million in direct medical costs plus substantial indirect savings. Ample clinical and cost-effectiveness data support these recommendations, and studies in Hong Kong and abroad could serve as models on how to implement them. We are confident that by applying these recommendations rigorously and systematically, a significant reduction in hip fractures in Hong Kong is achievable.
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Affiliation(s)
- T C Y Kwok
- Department of Medicine and Therapeutics, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong.,Jockey Club Centre for Osteoporosis Care and Control, The Chinese University of Hong Kong, Hong Kong.,Hong Kong Osteoporosis Foundation
| | - S W Law
- Hong Kong Osteoporosis Foundation.,Department of Orthopaedics and Traumatology, Alice Ho Miu Ling Nethersole Hospital, Hong Kong
| | - E M F Leung
- Hong Kong Osteoporosis Foundation.,Hong Kong Association of Gerontology
| | - D T K Choy
- Jockey Club Centre for Osteoporosis Care and Control, The Chinese University of Hong Kong, Hong Kong.,Hong Kong Osteoporosis Foundation
| | - P M S Lam
- Jockey Club Centre for Osteoporosis Care and Control, The Chinese University of Hong Kong, Hong Kong
| | - J C S Leung
- Jockey Club Centre for Osteoporosis Care and Control, The Chinese University of Hong Kong, Hong Kong
| | - S H Wong
- The Osteoporosis Society of Hong Kong
| | - T P Ip
- The Osteoporosis Society of Hong Kong.,Department of Medicine, Tung Wah Hospital, Hong Kong
| | - C L Cheung
- The Osteoporosis Society of Hong Kong.,Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong
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Tan K, Cheung CL, Yeung CY, Siu D, Leung J, Pang HK. Genetic screening for familial hypercholesterolaemia in Hong Kong. Hong Kong Med J 2018; 24 Suppl 3:7-10. [PMID: 29937437] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023] Open
Affiliation(s)
- K Tan
- Department of Medicine, The University of Hong Kong
| | - C L Cheung
- Department of Pharmacology and Pharmacy, The University of Hong Kong
| | - C Y Yeung
- Endocrine and Diabetes Centre, Hong Kong Sanatorium and Hospital
| | - D Siu
- Department of Medicine, The University of Hong Kong
| | - J Leung
- Department of Medicine, Ruttonjee Hospital
| | - H K Pang
- Department of Medicine, Pamela Youde Nethersole Eastern Hospital
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5
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Sing CW, Cheng VKF, Ho DKC, Kung AWC, Cheung BMY, Wong ICK, Tan KCB, Salas-Salvadó J, Becerra-Tomas N, Cheung CL. Serum calcium and incident diabetes: an observational study and meta-analysis. Osteoporos Int 2016; 27:1747-54. [PMID: 26659066 DOI: 10.1007/s00198-015-3444-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Accepted: 11/26/2015] [Indexed: 01/11/2023]
Abstract
UNLABELLED The study aimed to prospectively evaluate if serum calcium is related to diabetes incidence in Hong Kong Chinese. The results showed that serum calcium has a significant association with increased risk of diabetes. The result of meta-analysis reinforced our findings. INTRODUCTION This study aimed to evaluate the association of serum calcium, including serum total calcium and albumin-corrected calcium, with incident diabetes in Hong Kong Chinese. METHODS We conducted a retrospective cohort study in 6096 participants aged 20 or above and free of diabetes at baseline. Serum calcium was measured at baseline. Incident diabetes was determined from several electronic databases. We also searched relevant databases for studies on serum calcium and incident diabetes and conducted a meta-analysis using fixed-effect modeling. RESULTS During 59,130.9 person-years of follow-up, 631 participants developed diabetes. Serum total calcium and albumin-corrected calcium were associated with incident diabetes in the unadjusted model. After adjusting for demographic and clinical variables, the association remained significant only for serum total calcium (hazard ratio (HR), 1.32 (95 % confidence interval (CI), 1.02-1.70), highest vs. lowest quartile). In a meta-analysis of four studies including the current study, both serum total calcium (pooled risk ratio (RR), 1.38 (95 % CI, 1.15-1.65); I (2) = 5 %, comparing extreme quantiles) and albumin-corrected calcium (pooled RR, 1.29 (95 % CI, 1.03-1.61); I (2) = 0 %, comparing extreme quantiles) were associated with incident diabetes. Penalized regression splines showed that the association of incident diabetes with serum total calcium and albumin-correlated calcium was non-linear and linear, respectively. CONCLUSIONS Elevated serum calcium concentration is associated with incident diabetes. The mechanism underlying this association warrants further investigation.
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Affiliation(s)
- C W Sing
- Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, People's Republic of China
| | - V K F Cheng
- Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, People's Republic of China
| | - D K C Ho
- Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, People's Republic of China
| | - A W C Kung
- Department of Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, People's Republic of China
| | - B M Y Cheung
- Department of Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, People's Republic of China
- Research Centre of Heart, Brain, Hormone and Healthy Aging, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, People's Republic of China
- The State Key Laboratory of Pharmaceutical Biotechnology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, People's Republic of China
| | - I C K Wong
- Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, People's Republic of China
- The State Key Laboratory of Pharmaceutical Biotechnology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, People's Republic of China
- Research Department of Practice and Policy, School of Pharmacy, University College London, London, UK
| | - K C B Tan
- Department of Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, People's Republic of China
- Research Centre of Heart, Brain, Hormone and Healthy Aging, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, People's Republic of China
| | - J Salas-Salvadó
- Human Nutrition Unit, Faculty of Medicine and Health Sciences, Institut d'Investigacio Sanitaria Pere Virgili, Universitat Rovira i Virgili, Reus, Spain
- Centro de Investigación Biomédica en Red Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Institute of Health Carlos III, Madrid, Spain
| | - N Becerra-Tomas
- Human Nutrition Unit, Faculty of Medicine and Health Sciences, Institut d'Investigacio Sanitaria Pere Virgili, Universitat Rovira i Virgili, Reus, Spain
- Centro de Investigación Biomédica en Red Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Institute of Health Carlos III, Madrid, Spain
| | - C L Cheung
- Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, People's Republic of China.
- Department of Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, People's Republic of China.
- Research Centre of Heart, Brain, Hormone and Healthy Aging, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, People's Republic of China.
- The State Key Laboratory of Pharmaceutical Biotechnology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, People's Republic of China.
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7
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Koning GG, Keus F, Koeslag L, Cheung CL, Avçi M, van Laarhoven CJHM, Vriens PWHE. Randomized clinical trial of chronic pain after the transinguinal preperitoneal technique compared with Lichtenstein's method for inguinal hernia repair. Br J Surg 2012; 99:1365-73. [DOI: 10.1002/bjs.8862] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Abstract
Background
Preliminary experience has suggested that preperitoneal mesh positioning causes less chronic pain than Lichtenstein's technique for inguinal hernia repair. Therefore, a randomized clinical trial was conducted with the aim of evaluating the incidence of postoperative chronic pain after transinguinal preperitoneal (TIPP) mesh repair versus Lichtenstein's technique.
Methods
Patients with a primary unilateral inguinal hernia were randomized to either TIPP or Lichtenstein's repair in two training hospitals. The primary outcome was the number of patients with chronic pain after surgery. Secondary outcomes were adverse events. Follow-up was scheduled after 14 days, 3 months and 1 year. Patients and outcome assessors were blinded.
Results
A total of 302 patients were randomized to TIPP (143) or Lichtenstein (159) repair. Baseline characteristics were comparable in the two groups. Some 98·0 per cent of the patients were included in the analysis (141 in the TIPP group and 155 in the Lichtenstein group). Significantly fewer patients in the TIPP group had continuous chronic pain 1 year after surgery: five patients (3·5 per cent) versus 20 patients (12·9 per cent) in the Lichtenstein group (P = 0·004). An additional 12 patients (8·5 per cent) in the TIPP group and 60 (38·7 per cent) in the Lichtenstein group experienced pain during activity (P = 0·001). There were two patients with recurrence in the TIPP group and four in the Lichtenstein group, but no significant differences were found in other severe adverse events between the groups.
Conclusion
Fewer patients had continuous chronic pain at 1 year after the TIPP mesh inguinal hernia repair compared with Lichtenstein's repair. Registration number: ISRCTN93798494 (http://www.controlled-trials.com).
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Affiliation(s)
- G G Koning
- St. Elisabeth Hospital, Tilburg and Hernia Centre Brabant, Tilburg/Waalwijk, The Netherlands
- Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - F Keus
- Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - L Koeslag
- Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - C L Cheung
- St. Elisabeth Hospital, Tilburg and Hernia Centre Brabant, Tilburg/Waalwijk, The Netherlands
| | - M Avçi
- St. Elisabeth Hospital, Tilburg and Hernia Centre Brabant, Tilburg/Waalwijk, The Netherlands
| | | | - P W H E Vriens
- St. Elisabeth Hospital, Tilburg and Hernia Centre Brabant, Tilburg/Waalwijk, The Netherlands
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Cheung EYN, Bow CH, Cheung CL, Soong C, Yeung S, Loong C, Kung A. Discriminative value of FRAX for fracture prediction in a cohort of Chinese postmenopausal women. Osteoporos Int 2012; 23:871-8. [PMID: 21562875 DOI: 10.1007/s00198-011-1647-5] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [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] [Received: 11/13/2010] [Accepted: 02/24/2011] [Indexed: 10/18/2022]
Abstract
UNLABELLED We followed 2,266 postmenopausal Chinese women for 4.5 years to determine which model best predicts osteoporotic fracture. A model that contains ethnic-specific risk factors, some of which reflect frailty, performed as well as or better than the well-established FRAX model. INTRODUCTION Clinical risk assessment, with or without T-score, can predict fractures in Chinese postmenopausal women although it is unknown which combination of clinical risk factors is most effective. This prospective study sought to compare the accuracy for fracture prediction using various models including FRAX, our ethnic-specific clinical risk factors (CRF) and other simple models. METHODS This study is part of the Hong Kong Osteoporosis Study. A total of 2,266 treatment naïve postmenopausal women underwent clinical risk factor and bone mineral density assessment. Subjects were followed up for outcome of major osteoporotic fracture and receiver operating characteristic (ROC) curves for different models were compared. The percentage of subjects in different quartiles of risk according to various models who actually fractured was also compared. RESULTS The mean age at baseline was 62.1 ± 8.5 years and mean follow-up time was 4.5 ± 2.8 years. A total of 106 new major osteoporotic fractures were reported, of which 21 were hip fractures. Ethnic-specific CRF with T-score performed better than FRAX with T-score (based on both Chinese normative and National Health and Nutrition Examination Survey (NHANES) databases) in terms of AUC comparison for prediction of major osteoporotic fracture. The two models were similar in hip fracture prediction. The ethnic-specific CRF model had a 10% higher sensitivity than FRAX at a specificity of 0.8 or above. CONCLUSION CRF related to frailty and differences in lifestyle between populations are likely to be important in fracture prediction. Further work is required to determine which and how CRF can be applied to develop a fracture prediction model in our population.
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Affiliation(s)
- E Y N Cheung
- Department of Medicine, United Christian Hospital, Hong Kong, China.
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9
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Bow CH, Cheung E, Cheung CL, Xiao SM, Loong C, Soong C, Tan KC, Luckey MM, Cauley JA, Fujiwara S, Kung AWC. Ethnic difference of clinical vertebral fracture risk. Osteoporos Int 2012; 23:879-85. [PMID: 21461720 PMCID: PMC3277693 DOI: 10.1007/s00198-011-1627-9] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2011] [Accepted: 02/22/2011] [Indexed: 11/03/2022]
Abstract
UNLABELLED Vertebral fractures are the most common osteoporotic fractures. Data on the vertebral fracture risk in Asia remain sparse. This study observed that Hong Kong Chinese and Japanese populations have a less dramatic increase in hip fracture rates associated with age than Caucasians, but the vertebral fracture rates were higher, resulting in a high vertebral-to-hip fracture ratio. As a result, estimation of the absolute fracture risk for Asians may need to be readjusted for the higher clinical vertebral fracture rate. INTRODUCTION Vertebral fractures are the most common osteoporotic fractures. Data on the vertebral fracture risk in Asia remain sparse. The aim of this study was to report the incidence of clinical vertebral fractures among the Chinese and to compare the vertebral-to-hip fracture risk to other ethnic groups. METHODS Four thousand, three hundred eighty-six community-dwelling Southern Chinese subjects (2,302 women and 1,810 men) aged 50 or above were recruited in the Hong Kong Osteoporosis Study since 1995. Baseline demographic characteristics and medical history were obtained. Subjects were followed annually for fracture outcomes with a structured questionnaire and verified by the computerized patient information system of the Hospital Authority of the Hong Kong Government. Only non-traumatic incident hip fractures and clinical vertebral fractures that received medical attention were included in the analysis. The incidence rates of clinical vertebral fractures and hip fractures were determined and compared to the published data of Swedish Caucasian and Japanese populations. RESULTS The mean age at baseline was 62 ± 8.2 years for women and 68 ± 10.3 years for men. The average duration of follow-up was 4.0 ± 2.8 (range, 1 to 14) years for a total of 14,733 person-years for the whole cohort. The incidence rate for vertebral fracture was 194/100,000 person-years in men and 508/100,000 person-years in women, respectively. For subjects above the age of 65, the clinical vertebral fracture and hip fracture rates were 299/100,000 and 332/100,000 person-years, respectively, in men, and 594/100,000 and 379/100,000 person-years, respectively, in women. Hong Kong Chinese and Japanese populations have a less dramatic increase in hip fracture rates associated with age than Caucasians. At the age of 65 or above, the hip fracture rates for Asian (Hong Kong Chinese and Japanese) men and women were less than half of that in Caucasians, but the vertebral fracture rate was higher in Asians, resulting in a high vertebral-to-hip fracture ratio. CONCLUSIONS The incidences of vertebral and hip fractures, as well as the vertebral-to-hip fracture ratios vary in Asians and Caucasians. Estimation of the absolute fracture risk for Asians may need to be readjusted for the higher clinical vertebral fracture rate.
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Affiliation(s)
- C H Bow
- Department of Medicine, The University of Hong Kong, Hong Kong, China.
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10
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Cheung CL, Wedlake C, Moore J, Pautler SE, Peters TM. Sci-Thur PM: YIS - 02: Intraoperative Guidance for Minimally Invasive Abdominal Surgery Using Fused Video and Ultrasound Images: A Phantom Study. Med Phys 2010. [DOI: 10.1118/1.3476097] [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: 11/07/2022] Open
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Abstract
The emergence of pandemic H1N1/2009 influenza demonstrated that pandemic viruses could be generated in swine. Subsequent reintroduction of H1N1/2009 to swine has occurred in multiple countries. Through systematic surveillance of influenza viruses in swine from a Hong Kong abattoir, we characterize a reassortant progeny of H1N1/2009 with swine viruses. Swine experimentally infected with this reassortant developed mild illness and transmitted infection to contact animals. Continued reassortment of H1N1/2009 with swine influenza viruses could produce variants with transmissibility and altered virulence for humans. Global systematic surveillance of influenza viruses in swine is warranted.
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MESH Headings
- Abattoirs
- Animals
- Disease Outbreaks
- Genes, Viral
- Genotype
- Hemagglutinin Glycoproteins, Influenza Virus/genetics
- Hong Kong
- Humans
- Influenza A Virus, H1N1 Subtype/classification
- Influenza A Virus, H1N1 Subtype/genetics
- Influenza A Virus, H1N1 Subtype/isolation & purification
- Influenza A Virus, H1N1 Subtype/pathogenicity
- Influenza A Virus, H1N2 Subtype/classification
- Influenza A Virus, H1N2 Subtype/genetics
- Influenza A Virus, H1N2 Subtype/isolation & purification
- Influenza, Human/epidemiology
- Influenza, Human/virology
- Molecular Sequence Data
- Neuraminidase/genetics
- Orthomyxoviridae Infections/epidemiology
- Orthomyxoviridae Infections/transmission
- Orthomyxoviridae Infections/veterinary
- Orthomyxoviridae Infections/virology
- Phylogeny
- Population Surveillance
- Reassortant Viruses/classification
- Reassortant Viruses/genetics
- Reassortant Viruses/isolation & purification
- Swine/virology
- Swine Diseases/epidemiology
- Swine Diseases/transmission
- Swine Diseases/virology
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Affiliation(s)
| | | | - S. K. Ma
- State Key Laboratory of Emerging Infections Diseases and Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - O. T. W. Li
- State Key Laboratory of Emerging Infections Diseases and Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - C. L. Cheung
- State Key Laboratory of Emerging Infections Diseases and Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - G. J. D. Smith
- State Key Laboratory of Emerging Infections Diseases and Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - J. S. M. Peiris
- State Key Laboratory of Emerging Infections Diseases and Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Y. Guan
- State Key Laboratory of Emerging Infections Diseases and Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
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12
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Lai BMH, Cheung CL, Luk KDK, Kung AWC. Estrogen receptor alpha CA dinucleotide repeat polymorphism is associated with rate of bone loss in perimenopausal women and bone mineral density and risk of osteoporotic fractures in postmenopausal women. Osteoporos Int 2008; 19:571-9. [PMID: 17896124 DOI: 10.1007/s00198-007-0482-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [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] [Received: 04/11/2007] [Accepted: 08/24/2007] [Indexed: 11/29/2022]
Abstract
UNLABELLED The association between a newly identified CA repeat polymorphism of the estrogen receptor alpha gene (ESR1) with osteoporosis was investigated. Postmenopausal women with <18 CA repeats had low BMD, increased rate of bone loss and increased fracture risk. INTRODUCTION Studies have shown that intronic dinucleotide repeat polymorphisms in some genes are associated with disease risk by modulating mRNA splicing efficiency. D6S440 is a newly identified intronic CA repeat polymorphism located downstream of the 5'-splicing site of exon 5 of ESR1. METHODS The associations of D6S440 with bone mineral density (BMD), rate of bone loss and fracture risk were evaluated in 452 pre-, 110 peri- and 622 postmenopausal southern Chinese women using regression models. RESULTS Post- but not premenopausal women with less CA repeats had lower spine and hip BMD. The number of CA repeats was linearly related to hip BMD in postmenopausal women (beta=0.008; p=0.004). Postmenopausal women with CA repeats <18 had higher risks of having osteoporosis (BMD T-score< -2.5 at the spine: OR 2.46, 95% CI 1.30-4.65; at the hip: OR 3.79(1.64-8.74)) and low trauma fractures (OR 2.31(1.29-4.14)) than those with >or= 18 repeats. Perimenopausal women with <18 CA repeats had significantly greater bone loss in 18 months at the hip than those with >or= 18 repeats (-1.96% vs. -1.61%, p = 0.029). CONCLUSIONS ESR1 CA repeat polymorphism is associated with BMD variation, rate of bone loss and fracture risk, and this may be a useful genetic marker for fracture risk assessment.
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Affiliation(s)
- B M H Lai
- Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Pokfulam, Hong Kong, China
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13
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Cheung CL, Vijaykrishna D, Smith GJD, Fan XH, Zhang JX, Bahl J, Duan L, Huang K, Tai H, Wang J, Poon LLM, Peiris JSM, Chen H, Guan Y. Establishment of influenza A virus (H6N1) in minor poultry species in southern China. J Virol 2007; 81:10402-12. [PMID: 17652385 PMCID: PMC2045442 DOI: 10.1128/jvi.01157-07] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
An H6N1 virus, A/teal/Hong Kong/W312/97 (W312), was isolated during the "bird flu" incident in Hong Kong in 1997. Genetic analysis suggested that this virus might be the progenitor of the A/Hong Kong/156/97 (HK/97) H5N1 virus, as seven of eight gene segments of those viruses had a common source. Continuing surveillance in Hong Kong showed that a W312-like virus was prevalent in quail and pheasants in 1999; however, the further development of H6N1 viruses has not been investigated since 2001. Here we report influenza virus surveillance data collected in southern China from 2000 to 2005 that show that H6N1 viruses have become established and endemic in minor poultry species and replicate mainly in the respiratory tract. Phylogenetic analysis indicated that all H6N1 isolates had W312-like hemagglutinin and neuraminidase genes. However, reassortment of internal genes between different subtype virus lineages, including H5N1, H9N2, and other avian viruses, generated multiple novel H6N1 genotypes in different types of poultry. These novel H6N1/N2 viruses are double, triple, or even quadruple reassortants. Reassortment between a W312-like H6N1 virus and an A/quail/Hong Kong/G1/97 (HK/97)-like H9N2 virus simultaneously generated novel H6N2 subtype viruses that were persistent in poultry. Molecular analyses suggest that W312-like viruses may not be the precursors of HK/97 virus but reassortants from an HK/97-like virus and another unidentified H6 subtype virus. These results provide further evidence of the pivotal role of the live poultry market system of southern China in generating increased genetic diversity in influenza viruses in this region.
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Affiliation(s)
- C L Cheung
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, The University of Hong Kong, Li Ka Shing Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong, SAR, China
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14
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Smith GJD, Fan XH, Wang J, Li KS, Qin K, Zhang JX, Vijaykrishna D, Cheung CL, Huang K, Rayner JM, Peiris JSM, Chen H, Webster RG, Guan Y. Emergence and predominance of an H5N1 influenza variant in China. Proc Natl Acad Sci U S A 2006; 103:16936-41. [PMID: 17075062 PMCID: PMC1636557 DOI: 10.1073/pnas.0608157103] [Citation(s) in RCA: 225] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The development of highly pathogenic avian H5N1 influenza viruses in poultry in Eurasia accompanied with the increase in human infection in 2006 suggests that the virus has not been effectively contained and that the pandemic threat persists. Updated virological and epidemiological findings from our market surveillance in southern China demonstrate that H5N1 influenza viruses continued to be panzootic in different types of poultry. Genetic and antigenic analyses revealed the emergence and predominance of a previously uncharacterized H5N1 virus sublineage (Fujian-like) in poultry since late 2005. Viruses from this sublineage gradually replaced those multiple regional distinct sublineages and caused recent human infection in China. These viruses have already transmitted to Hong Kong, Laos, Malaysia, and Thailand, resulting in a new transmission and outbreak wave in Southeast Asia. Serological studies suggest that H5N1 seroconversion in market poultry is low and that vaccination may have facilitated the selection of the Fujian-like sublineage. The predominance of this virus over a large geographical region within a short period directly challenges current disease control measures.
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MESH Headings
- Animals
- Antigenic Variation
- Antigens, Viral/genetics
- China/epidemiology
- Evolution, Molecular
- Genetic Variation
- Hemagglutinin Glycoproteins, Influenza Virus/genetics
- Hemagglutinin Glycoproteins, Influenza Virus/immunology
- Humans
- Influenza A Virus, H5N1 Subtype/genetics
- Influenza A Virus, H5N1 Subtype/immunology
- Influenza A Virus, H5N1 Subtype/isolation & purification
- Influenza A Virus, H5N1 Subtype/pathogenicity
- Influenza in Birds/epidemiology
- Influenza in Birds/virology
- Influenza, Human/epidemiology
- Influenza, Human/virology
- Molecular Epidemiology
- Molecular Sequence Data
- Phylogeny
- Poultry/virology
- Selection, Genetic
- Time Factors
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Affiliation(s)
- G. J. D. Smith
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, Li Ka Shing Faculty of Medicine, University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong Special Administration Region, China; and
| | - X. H. Fan
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, Li Ka Shing Faculty of Medicine, University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong Special Administration Region, China; and
| | - J. Wang
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, Li Ka Shing Faculty of Medicine, University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong Special Administration Region, China; and
| | - K. S. Li
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, Li Ka Shing Faculty of Medicine, University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong Special Administration Region, China; and
| | - K. Qin
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, Li Ka Shing Faculty of Medicine, University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong Special Administration Region, China; and
| | - J. X. Zhang
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, Li Ka Shing Faculty of Medicine, University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong Special Administration Region, China; and
| | - D. Vijaykrishna
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, Li Ka Shing Faculty of Medicine, University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong Special Administration Region, China; and
| | - C. L. Cheung
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, Li Ka Shing Faculty of Medicine, University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong Special Administration Region, China; and
| | - K. Huang
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, Li Ka Shing Faculty of Medicine, University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong Special Administration Region, China; and
| | - J. M. Rayner
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, Li Ka Shing Faculty of Medicine, University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong Special Administration Region, China; and
| | - J. S. M. Peiris
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, Li Ka Shing Faculty of Medicine, University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong Special Administration Region, China; and
| | - H. Chen
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, Li Ka Shing Faculty of Medicine, University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong Special Administration Region, China; and
| | - R. G. Webster
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, Li Ka Shing Faculty of Medicine, University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong Special Administration Region, China; and
- Virology Division, Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN 38105
- To whom correspondence may be addressed. E-mail:
or
| | - Y. Guan
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, Li Ka Shing Faculty of Medicine, University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong Special Administration Region, China; and
- To whom correspondence may be addressed. E-mail:
or
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15
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Tang XC, Zhang JX, Zhang SY, Wang P, Fan XH, Li LF, Li G, Dong BQ, Liu W, Cheung CL, Xu KM, Song WJ, Vijaykrishna D, Poon LLM, Peiris JSM, Smith GJD, Chen H, Guan Y. Prevalence and genetic diversity of coronaviruses in bats from China. J Virol 2006; 80:7481-90. [PMID: 16840328 PMCID: PMC1563713 DOI: 10.1128/jvi.00697-06] [Citation(s) in RCA: 259] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Coronaviruses can infect a variety of animals including poultry, livestock, and humans and are currently classified into three groups. The interspecies transmissions of coronaviruses between different hosts form a complex ecosystem of which little is known. The outbreak of severe acute respiratory syndrome (SARS) and the recent identification of new coronaviruses have highlighted the necessity for further investigation of coronavirus ecology, in particular the role of bats and other wild animals. In this study, we sampled bat populations in 15 provinces of China and reveal that approximately 6.5% of the bats, from diverse species distributed throughout the region, harbor coronaviruses. Full genomes of four coronavirues from bats were sequenced and analyzed. Phylogenetic analyses of the spike, envelope, membrane, and nucleoprotein structural proteins and the two conserved replicase domains, putative RNA-dependent RNA polymerase and RNA helicase, revealed that bat coronaviruses cluster in three different groups: group 1, another group that includes all SARS and SARS-like coronaviruses (putative group 4), and an independent bat coronavirus group (putative group 5). Further genetic analyses showed that different species of bats maintain coronaviruses from different groups and that a single bat species from different geographic locations supports similar coronaviruses. Thus, the findings of this study suggest that bats may play an integral role in the ecology and evolution of coronaviruses.
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Affiliation(s)
- X C Tang
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, The University of Hong Kong, Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong SAR, China
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16
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Smith GJD, Naipospos TSP, Nguyen TD, de Jong MD, Vijaykrishna D, Usman TB, Hassan SS, Nguyen TV, Dao TV, Bui NA, Leung YHC, Cheung CL, Rayner JM, Zhang JX, Zhang LJ, Poon LLM, Li KS, Nguyen VC, Hien TT, Farrar J, Webster RG, Chen H, Peiris JSM, Guan Y. Evolution and adaptation of H5N1 influenza virus in avian and human hosts in Indonesia and Vietnam. Virology 2006; 350:258-68. [PMID: 16713612 DOI: 10.1016/j.virol.2006.03.048] [Citation(s) in RCA: 181] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2006] [Revised: 03/21/2006] [Accepted: 03/27/2006] [Indexed: 11/24/2022]
Abstract
Highly pathogenic avian influenza virus H5N1 is endemic in poultry in East and Southeast Asia with disease outbreaks recently spreading to parts of central Asia, Europe and Africa. Continued interspecies transmission to humans has been reported in Vietnam, Thailand, Cambodia, Indonesia and China, causing pandemic concern. Here, we genetically characterize 82 H5N1 viruses isolated from poultry throughout Indonesia and Vietnam and 11 human isolates from southern Vietnam together with sequence data available in public databases to address questions relevant to virus introduction, endemicity and evolution. Phylogenetic analysis shows that all viruses from Indonesia form a distinct sublineage of H5N1 genotype Z viruses suggesting this outbreak likely originated from a single introduction that spread throughout the country during the past two years. Continued virus activities in Indonesia were attributed to transmission via poultry movement within the country rather than through repeated introductions by bird migration. Within Indonesia and Vietnam, H5N1 viruses have evolved over time into geographically distinct groups within each country. Molecular analysis of the H5N1 genotype Z genome shows that only the M2 and PB1-F2 genes were under positive selection, suggesting that these genes might be involved in adaptation of this virus to new hosts following interspecies transmission. At the amino acid level 12 residues were under positive selection in those genotype Z viruses, in the HA and PB1-F2 proteins. Some of these residues were more frequently observed in human isolates than in avian isolates and are related to viral antigenicity and receptor binding. Our study provides insight into the ongoing evolution of H5N1 influenza viruses that are transmitting in diverse avian species and at the interface between avian and human hosts.
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Affiliation(s)
- G J D Smith
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, The University of Hong Kong, Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong SAR, China
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17
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Chen H, Smith GJD, Li KS, Wang J, Fan XH, Rayner JM, Vijaykrishna D, Zhang JX, Zhang LJ, Guo CT, Cheung CL, Xu KM, Duan L, Huang K, Qin K, Leung YHC, Wu WL, Lu HR, Chen Y, Xia NS, Naipospos TSP, Yuen KY, Hassan SS, Bahri S, Nguyen TD, Webster RG, Peiris JSM, Guan Y. Establishment of multiple sublineages of H5N1 influenza virus in Asia: implications for pandemic control. Proc Natl Acad Sci U S A 2006; 103:2845-50. [PMID: 16473931 PMCID: PMC1413830 DOI: 10.1073/pnas.0511120103] [Citation(s) in RCA: 453] [Impact Index Per Article: 25.2] [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: 02/05/2023] Open
Abstract
Preparedness for a possible influenza pandemic caused by highly pathogenic avian influenza A subtype H5N1 has become a global priority. The spread of the virus to Europe and continued human infection in Southeast Asia have heightened pandemic concern. It remains unknown from where the pandemic strain may emerge; current attention is directed at Vietnam, Thailand, and, more recently, Indonesia and China. Here, we report that genetically and antigenically distinct sublineages of H5N1 virus have become established in poultry in different geographical regions of Southeast Asia, indicating the long-term endemicity of the virus, and the isolation of H5N1 virus from apparently healthy migratory birds in southern China. Our data show that H5N1 influenza virus, has continued to spread from its established source in southern China to other regions through transport of poultry and bird migration. The identification of regionally distinct sublineages contributes to the understanding of the mechanism for the perpetuation and spread of H5N1, providing information that is directly relevant to control of the source of infection in poultry. It points to the necessity of surveillance that is geographically broader than previously supposed and that includes H5N1 viruses of greater genetic and antigenic diversity.
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Affiliation(s)
- H. Chen
- Joint Influenza Research Centre (Shantou University Medical College and Hong Kong University), Shantou University Medical College, Shantou, Guangdong 515031, China
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, University of Hong Kong, Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong SAR, China
| | - G. J. D. Smith
- Joint Influenza Research Centre (Shantou University Medical College and Hong Kong University), Shantou University Medical College, Shantou, Guangdong 515031, China
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, University of Hong Kong, Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong SAR, China
| | - K. S. Li
- Joint Influenza Research Centre (Shantou University Medical College and Hong Kong University), Shantou University Medical College, Shantou, Guangdong 515031, China
| | - J. Wang
- Joint Influenza Research Centre (Shantou University Medical College and Hong Kong University), Shantou University Medical College, Shantou, Guangdong 515031, China
| | - X. H. Fan
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, University of Hong Kong, Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong SAR, China
| | - J. M. Rayner
- Joint Influenza Research Centre (Shantou University Medical College and Hong Kong University), Shantou University Medical College, Shantou, Guangdong 515031, China
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, University of Hong Kong, Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong SAR, China
| | - D. Vijaykrishna
- Joint Influenza Research Centre (Shantou University Medical College and Hong Kong University), Shantou University Medical College, Shantou, Guangdong 515031, China
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, University of Hong Kong, Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong SAR, China
| | - J. X. Zhang
- Joint Influenza Research Centre (Shantou University Medical College and Hong Kong University), Shantou University Medical College, Shantou, Guangdong 515031, China
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, University of Hong Kong, Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong SAR, China
| | - L. J. Zhang
- Joint Influenza Research Centre (Shantou University Medical College and Hong Kong University), Shantou University Medical College, Shantou, Guangdong 515031, China
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, University of Hong Kong, Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong SAR, China
| | - C. T. Guo
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, University of Hong Kong, Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong SAR, China
| | - C. L. Cheung
- Joint Influenza Research Centre (Shantou University Medical College and Hong Kong University), Shantou University Medical College, Shantou, Guangdong 515031, China
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, University of Hong Kong, Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong SAR, China
| | - K. M. Xu
- Joint Influenza Research Centre (Shantou University Medical College and Hong Kong University), Shantou University Medical College, Shantou, Guangdong 515031, China
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, University of Hong Kong, Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong SAR, China
| | - L. Duan
- Joint Influenza Research Centre (Shantou University Medical College and Hong Kong University), Shantou University Medical College, Shantou, Guangdong 515031, China
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, University of Hong Kong, Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong SAR, China
| | - K. Huang
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, University of Hong Kong, Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong SAR, China
| | - K. Qin
- Joint Influenza Research Centre (Shantou University Medical College and Hong Kong University), Shantou University Medical College, Shantou, Guangdong 515031, China
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, University of Hong Kong, Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong SAR, China
| | - Y. H. C. Leung
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, University of Hong Kong, Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong SAR, China
| | - W. L. Wu
- Joint Influenza Research Centre (Shantou University Medical College and Hong Kong University), Shantou University Medical College, Shantou, Guangdong 515031, China
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, University of Hong Kong, Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong SAR, China
| | - H. R. Lu
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, University of Hong Kong, Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong SAR, China
| | - Y. Chen
- Research Center for Medical Molecular Virology of Fujian Province, Xiamen University, Xiamen, Fujian 361005, China
| | - N. S. Xia
- Research Center for Medical Molecular Virology of Fujian Province, Xiamen University, Xiamen, Fujian 361005, China
| | - T. S. P. Naipospos
- Ministry of Agriculture and Animal Health, Government of Indonesia, Pasar Minggu, Jakarta Selatan 12550, Indonesia
| | - K. Y. Yuen
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, University of Hong Kong, Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong SAR, China
| | - S. S. Hassan
- Veterinary Research Institute, 31 400 Ipoh, Malaysia
| | - S. Bahri
- Ministry of Agriculture and Animal Health, Government of Indonesia, Pasar Minggu, Jakarta Selatan 12550, Indonesia
| | - T. D. Nguyen
- **National Institute of Veterinary Research, Dong Da, Hanoi, Vietnam; and
| | - R. G. Webster
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, University of Hong Kong, Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong SAR, China
- **National Institute of Veterinary Research, Dong Da, Hanoi, Vietnam; and
- To whom correspondence may be addressed. E-mail:
or
| | - J. S. M. Peiris
- Joint Influenza Research Centre (Shantou University Medical College and Hong Kong University), Shantou University Medical College, Shantou, Guangdong 515031, China
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, University of Hong Kong, Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong SAR, China
| | - Y. Guan
- Joint Influenza Research Centre (Shantou University Medical College and Hong Kong University), Shantou University Medical College, Shantou, Guangdong 515031, China
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, University of Hong Kong, Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong SAR, China
- To whom correspondence may be addressed. E-mail:
or
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18
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Guan Y, Poon LLM, Cheung CY, Ellis TM, Lim W, Lipatov AS, Chan KH, Sturm-Ramirez KM, Cheung CL, Leung YHC, Yuen KY, Webster RG, Peiris JSM. H5N1 influenza: a protean pandemic threat. Proc Natl Acad Sci U S A 2004; 101:8156-61. [PMID: 15148370 PMCID: PMC419573 DOI: 10.1073/pnas.0402443101] [Citation(s) in RCA: 298] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Infection with avian influenza A virus of the H5N1 subtype (isolates A/HK/212/03 and A/HK/213/03) was fatal to one of two members of a family in southern China in 2003. This incident was preceded by lethal outbreaks of H5N1 influenza in waterfowl, which are the natural hosts of these viruses and, therefore, normally have asymptomatic infection. The hemagglutinin genes of the A/HK/212/03-like viruses isolated from humans and waterfowl share the lineage of the H5N1 viruses that caused the first known cases of human disease in Hong Kong in 1997, but their internal protein genes originated elsewhere. The hemagglutinin of the recent human isolates has undergone significant antigenic drift. Like the 1997 human H5N1 isolates, the 2003 human H5N1 isolates induced the overproduction of proinflammatory cytokines by primary human macrophages in vitro, whereas the precursor H5N1 viruses and other H5N1 reassortants isolated in 2001 did not. The acquisition by the viruses of characteristics that enhance virulence in humans and waterfowl and their potential for wider distribution by infected migrating birds are causes for renewed pandemic concern.
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Affiliation(s)
- Y Guan
- Department of Microbiology, University of Hong Kong, Hong Kong SAR, People's Republic of China.
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19
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Guan Y, Zheng BJ, He YQ, Liu XL, Zhuang ZX, Cheung CL, Luo SW, Li PH, Zhang LJ, Guan YJ, Butt KM, Wong KL, Chan KW, Lim W, Shortridge KF, Yuen KY, Peiris JSM, Poon LLM. Isolation and characterization of viruses related to the SARS coronavirus from animals in southern China. Science 2003; 302:276-8. [PMID: 12958366 DOI: 10.1126/science.1087139] [Citation(s) in RCA: 1549] [Impact Index Per Article: 73.8] [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: 11/02/2022]
Abstract
A novel coronavirus (SCoV) is the etiological agent of severe acute respiratory syndrome (SARS). SCoV-like viruses were isolated from Himalayan palm civets found in a live-animal market in Guangdong, China. Evidence of virus infection was also detected in other animals (including a raccoon dog, Nyctereutes procyonoides) and in humans working at the same market. All the animal isolates retain a 29-nucleotide sequence that is not found in most human isolates. The detection of SCoV-like viruses in small, live wild mammals in a retail market indicates a route of interspecies transmission, although the natural reservoir is not known.
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Affiliation(s)
- Y Guan
- Department of Microbiology, The University of Hong Kong, University Pathology Building, Queen Mary Hospital, Hong Kong Special Administrative Region, People's Republic of China.
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20
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Schnitzler GR, Cheung CL, Hafner JH, Saurin AJ, Kingston RE, Lieber CM. Direct imaging of human SWI/SNF-remodeled mono- and polynucleosomes by atomic force microscopy employing carbon nanotube tips. Mol Cell Biol 2001; 21:8504-11. [PMID: 11713285 PMCID: PMC100013 DOI: 10.1128/mcb.21.24.8504-8511.2001] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Chromatin-remodeling complexes alter chromatin structure to facilitate, or in some cases repress, gene expression. Recent studies have suggested two potential pathways by which such regulation might occur. In the first, the remodeling complex repositions nucleosomes along DNA to open or occlude regulatory sites. In the second, the remodeling complex creates an altered dimeric form of the nucleosome that has altered accessibility to transcription factors. The extent of translational repositioning, the structure of the remodeled dimer, and the presence of dimers on remodeled polynucleosomes have been difficult to gauge by biochemical assays. To address these questions, ultrahigh-resolution carbon nanotube tip atomic force microscopy was used to examine the products of remodeling reactions carried out by the human SWI/SNF (hSWI/SNF) complex. We found that mononucleosome remodeling by hSWI/SNF resulted in a dimer of mononucleosomes in which approximately 60 bp of DNA is more weakly bound than in control nucleosomes. Arrays of evenly spaced nucleosomes that were positioned by 5S rRNA gene sequences were disorganized by hSWI/SNF, and this resulted in long stretches of bare DNA, as well as clusters of nucleosomes. The formation of structurally altered nucleosomes on the array is suggested by a significant increase in the fraction of closely abutting nucleosome pairs and by a general destabilization of nucleosomes on the array. These results suggest that both the repositioning and structural alteration of nucleosomes are important aspects of hSWI/SNF action on polynucleosomes.
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Affiliation(s)
- G R Schnitzler
- Department of Biochemistry, Tufts University School of Medicine, 136 Harrison Ave., Boston, MA 02111, USA.
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21
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Abstract
Atomic force microscopy (AFM) has great potential as a tool for structural biology, a field in which there is increasing demand to characterize larger and more complex biomolecular systems. However, the poorly characterized silicon and silicon nitride probe tips currently employed in AFM limit its biological applications. Carbon nanotubes represent ideal AFM tip materials due to their small diameter, high aspect ratio, large Young's modulus, mechanical robustness, well-defined structure, and unique chemical properties. Nanotube probes were first fabricated by manual assembly, but more recent methods based on chemical vapor deposition provide higher resolution probes and are geared towards mass production, including recent developments that enable quantitative preparation of individual single-walled carbon nanotube tips [J. Phys. Chem. B 105 (2001) 743]. The high-resolution imaging capabilities of these nanotube AFM probes have been demonstrated on gold nanoparticles and well-characterized biomolecules such as IgG and GroES. Using the nanotube probes, new biological structures have been investigated in the areas of amyloid-beta protein aggregation and chromatin remodeling, and new biotechnologies have been developed such as AFM-based haplotyping. In addition to measuring topography, chemically functionalized AFM probes can measure the spatial arrangement of chemical functional groups in a sample. However, standard silicon and silicon nitride tips, once functionalized, do not yield sufficient resolution to allow combined structural and functional imaging of biomolecules. The unique end-group chemistry of carbon nanotubes, which can be arbitrarily modified by established chemical methods, has been exploited for chemical force microscopy, allowing single-molecule measurements with well-defined functionalized tips.
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Affiliation(s)
- J H Hafner
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
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22
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Abstract
Metallic single-walled carbon nanotubes have been proposed to be good one-dimensional conductors. However, the finite curvature of the graphene sheet that forms the nanotubes and the broken symmetry due to the local environment may modify their electronic properties. We used low-temperature atomically resolved scanning tunneling microscopy to investigate zigzag and armchair nanotubes, both thought to be metallic. "Metallic" zigzag nanotubes were found to have energy gaps with magnitudes that depend inversely on the square of the tube radius, whereas isolated armchair tubes do not have energy gaps. Additionally, armchair nanotubes packed in bundles have pseudogaps, which exhibit an inverse dependence on tube radius. These observed energy gaps suggest that most "metallic" single-walled nanotubes are not true metals, and they have implications for our understanding of the electronic properties and potential applications of carbon nanotubes.
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Affiliation(s)
- M Ouyang
- Department of Chemistry and Chemical Biology, Division of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA
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23
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Abstract
Intramolecular junctions in single-walled carbon nanotubes are potentially ideal structures for building robust, molecular-scale electronics but have only been studied theoretically at the atomic level. Scanning tunneling microscopy was used to determine the atomic structure and electronic properties of such junctions in single-walled nanotube samples. Metal-semiconductor junctions are found to exhibit an electronically sharp interface without localized junction states, whereas a more diffuse interface and low-energy states are found in metal-metal junctions. Tight-binding calculations for models based on observed atomic structures show good agreement with spectroscopy and provide insight into the topological defects forming intramolecular junctions. These studies have important implications for applications of present materials and provide a means for assessing efforts designed to tailor intramolecular junctions for nanoelectronics.
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Affiliation(s)
- M Ouyang
- Department of Chemistry and Chemical Biology and, Division of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA
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24
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Abstract
Single-walled carbon nanotubes are ideal systems for investigating fundamental properties and applications of one-dimensional electronic systems. The interaction of magnetic impurities with electrons confined in one dimension has been studied by spatially resolving the local electronic density of states of small cobalt clusters on metallic single-walled nanotubes with a low-temperature scanning tunneling microscope. Spectroscopic measurements performed on and near these clusters exhibit a narrow peak near the Fermi level that has been identified as a Kondo resonance. Using the scanning tunneling microscope to fabricate ultrasmall magnetic nanostructures consisting of small cobalt clusters on short nanotube pieces, spectroscopic studies of this quantum box structure exhibited features characteristic of the bulk Kondo resonance, but also new features due to finite size.
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Affiliation(s)
- T W Odom
- Department of Chemistry and Chemical Biology, and Division of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA
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25
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Abstract
Carbon nanotubes represent ideal probes for high-resolution structural and chemical imaging of biomolecules with atomic force microscopy. Recent advances in fabrication of carbon nanotube probes with sub-nanometer radii promise to yield unique insights into the structure, dynamics and function of biological macromolecules and complexes.
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Affiliation(s)
- A T Woolley
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA 02138, USA
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26
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Abstract
A concept for molecular electronics exploiting carbon nanotubes as both molecular device elements and molecular wires for reading and writing information was developed. Each device element is based on a suspended, crossed nanotube geometry that leads to bistable, electrostatically switchable ON/OFF states. The device elements are naturally addressable in large arrays by the carbon nanotube molecular wires making up the devices. These reversible, bistable device elements could be used to construct nonvolatile random access memory and logic function tables at an integration level approaching 10(12) elements per square centimeter and an element operation frequency in excess of 100 gigahertz. The viability of this concept is demonstrated by detailed calculations and by the experimental realization of a reversible, bistable nanotube-based bit.
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Affiliation(s)
- T Rueckes
- Department of Chemistry and Chemical Biology, Division of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA
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27
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Cheung CL, Hafner JH, Lieber CM. Carbon nanotube atomic force microscopy tips: direct growth by chemical vapor deposition and application to high-resolution imaging. Proc Natl Acad Sci U S A 2000; 97:3809-13. [PMID: 10737761 PMCID: PMC18098 DOI: 10.1073/pnas.050498597] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.0] [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: 11/18/2022] Open
Abstract
Carbon nanotubes are potentially ideal atomic force microscopy probes because they can have diameters as small as one nanometer, have robust mechanical properties, and can be specifically functionalized with chemical and biological probes at the tip ends. This communication describes methods for the direct growth of carbon nanotube tips by chemical vapor deposition (CVD) using ethylene and iron catalysts deposited on commercial silicon-cantilever-tip assemblies. Scanning electron microscopy and transmission electron microscopy measurements demonstrate that multiwalled nanotube and single-walled nanotube tips can be grown by predictable variations in the CVD growth conditions. Force-displacement measurements made on the tips show that they buckle elastically and have very small (</= 100 pN) nonspecific adhesion on mica surfaces in air. Analysis of images recorded on gold nanoparticle standards shows that these multi- and single-walled carbon nanotube tips have radii of curvature of 3-6 and 2-4 nm, respectively. Moreover, the nanotube tip radii determined from the nanoparticle images are consistent with those determined directly by transmission electron microscopy imaging of the nanotube ends. These molecular-scale CVD nanotube probes have been used to image isolated IgG and GroES proteins at high-resolution.
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Affiliation(s)
- C L Cheung
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
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28
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Abstract
Carbon nanotubes combine a range of properties that make them well suited for use as probe tips in applications such as atomic force microscopy (AFM). Their high aspect ratio, for example, opens up the possibility of probing the deep crevices that occur in microelectronic circuits, and the small effective radius of nanotube tips significantly improves the lateral resolution beyond what can be achieved using commercial silicon tips. Another characteristic feature of nanotubes is their ability to buckle elastically, which makes them very robust while limiting the maximum force that is applied to delicate organic and biological samples. Earlier investigations into the performance of nanotubes as scanning probe microscopy tips have focused on topographical imaging, but a potentially more significant issue is the question of whether nanotubes can be modified to create probes that can sense and manipulate matter at the molecular level. Here we demonstrate that nanotube tips with the capability of chemical and biological discrimination can be created with acidic functionality and by coupling basic or hydrophobic functionalities or biomolecular probes to the carboxyl groups that are present at the open tip ends. We have used these modified nanotubes as AFM tips to titrate the acid and base groups, to image patterned samples based on molecular interactions, and to measure the binding force between single protein-ligand pairs. As carboxyl groups are readily derivatized by a variety of reactions, the preparation of a wide range of functionalized nanotube tips should be possible, thus creating molecular probes with potential applications in many areas of chemistry and biology.
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Affiliation(s)
- S S Wong
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA
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Tonnaer JA, Cheung CL, De Boer T. cGMP formation and phosphoinositide turnover in rat brain slices are mediated by pharmacologically distinct muscarinic acetylcholine receptors. Eur J Pharmacol 1991; 207:183-8. [PMID: 1680060 DOI: 10.1016/0922-4106(91)90029-h] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [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: 12/28/2022]
Abstract
The cGMP response and the accumulation of inositol monophosphate (IP) induced by carbachol were compared in slices of different rat brain structures. Basal cGMP and the responses of cGMP to carbachol appeared dependent on the concentration of added Ca2+, suggesting that distinct Ca(2+)-mediated and Ca(2+)-sensitive muscarinic receptor-mediated mechanisms stimulate guanylate cyclase. Regional responses of cGMP to carbachol or to direct stimulation of guanylate cyclase with sodium nitroprusside were markedly distinct, indicating that a major proportion of guanylate cyclase in the cortex, an intermediate proportion in other forebrain regions, and only a minor proportion in the brainstem is sensitive to muscarinic receptor stimulation. The regional patterns of IP and cGMP responses to carbachol were different in the forebrain. Maximal IP accumulation was found in the cortex, whereas cGMP responses were highest in the hippocampus. Moreover, IP and cGMP formation in the hippocampus were differently antagonized by atropine, 4-diphenylacetoxy-N-methyl piperidine methiodide (4-DAMP), the M2-receptor subtype-preferring antagonist AF-DX 116 and the M1-selective antagonist pirenzepine. These data support the notion that the IP formation induced by carbachol in the forebrain predominantly is mediated by muscarinic receptors of the M1 subtype, and indicate the involvement of muscarinic receptors of the M3 subtype in the carbachol-induced cGMP formation.
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Affiliation(s)
- J A Tonnaer
- CNS Pharmacology Department, Organon International, Oss, The Netherlands
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