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1.
Hong Kong Med J ; 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39188163

RESUMO

Chronic kidney disease (CKD) imposes a significant burden on healthcare systems worldwide, and diabetes is a major risk factor for CKD. There is currently no consensus in Hong Kong regarding the prioritisation of early identification and intervention for CKD. A comprehensive and Hong Kong-specific diabetes and CKD treatment guideline is also lacking. A multidisciplinary group of experts discussed issues surrounding the current management of CKD and reviewed evidence in the context of local experience to support recommendations. The experts used a modified Delphi approach to finalise recommendations. Consensus was regarded as ≥75% acceptability among all expert panel members. The panel members finalised 14 CKD-focused consensus statements addressing disease definition, screening, disease monitoring, lifestyle management, and treatment strategies. The recommendations provided are relevant to the Hong Kong healthcare setting and can be used as a guide by physicians across various specialties to facilitate the appropriate management of CKD.

2.
J Endocrinol Invest ; 45(11): 2149-2156, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35831586

RESUMO

PURPOSE: Thyroid dysfunction in COVID-19 carries clinical and prognostic implications. In this study, we developed a prediction score (ThyroCOVID) for abnormal thyroid function (TFT) on admission amongst COVID-19 patients. METHODS: Consecutive COVID-19 patients admitted to Queen Mary Hospital were prospectively recruited during July 2020-May 2021. Thyroid-stimulating hormone (TSH), free thyroxine (fT4) and free triiodothyronine (fT3) were measured on admission. Multivariable logistic regression analysis was performed to identify independent determinants of abnormal TFTs. ThyroCOVID was developed based on a clinical model with the lowest Akaike information criteria. RESULTS: Five hundred and forty six COVID-19 patients were recruited (median age 50 years, 45.4% men, 72.9% mild disease on admission). 84 patients (15.4%) had abnormal TFTs on admission. Patients with abnormal TFTs were more likely to be older, have more comorbidities, symptomatic, have worse COVID-19 severity, higher SARS-CoV-2 viral loads and more adverse profile of acute-phase reactants, haematological and biochemical parameters. ThyroCOVID consisted of five parameters: symptoms (malaise), comorbidities (ischaemic heart disease/congestive heart failure) and laboratory parameters (lymphocyte count, C-reactive protein, and SARS-CoV-2 cycle threshold values). It was able to identify abnormal TFT on admission with an AUROC of 0.73 (95% CI 0.67-0.79). The optimal cut-off of 0.15 had a sensitivity of 75.0%, specificity of 65.2%, negative predictive value of 93.5% and positive predictive value of 28.1% in identifying abnormal TFTs on admission amongst COVID-19 patients. CONCLUSION: ThyroCOVID, a prediction score to identify COVID-19 patients at risk of having abnormal TFT on admission, was developed based on a cohort of predominantly non-severe COVID-19 patients.


Assuntos
COVID-19 , Tri-Iodotironina , Proteína C-Reativa , COVID-19/diagnóstico , COVID-19/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , SARS-CoV-2 , Testes de Função Tireóidea , Glândula Tireoide , Tireotropina , Tiroxina
3.
J Endocrinol Invest ; 44(3): 523-530, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32602078

RESUMO

PURPOSE: Findings on trabecular bone score (TBS), an index of bone quality, have been reported in prediabetes defined by impaired fasting glucose or HbA1c. Here, we assessed the bone mineral density (BMD) and TBS in prediabetes individuals with impaired glucose tolerance (IGT), and investigated the association of these bone parameters with serum levels of fibroblast growth factor 21 (FGF21), a hormone implicated in bone metabolism and with higher levels in IGT. METHODS: Chinese postmenopausal women aged 55-80 years, without diabetes, were recruited from the Hong Kong Cardiovascular Risk Factor Prevalence Study in 2016-2018. Normal glucose tolerance (NGT) was defined by fasting glucose < 5.6 mmol/L and 2-h plasma glucose (2hG) < 7.8 mmol/L, and IGT by 2hG 7.8-11 mmol/L. Serum levels of FGF21 and other bone metabolism regulators were measured. Insulin sensitivity was assessed by the Matsuda index. Independent determinants of TBS were evaluated using multivariable stepwise linear regression. RESULTS: 173 individuals with NGT and 73 with IGT were included. TBS was lower in those with IGT compared to those with NGT, while BMD was comparable. Individuals with IGT had significantly higher serum FGF21 levels, which in turn showed an independent inverse relationship with TBS, attenuated after inclusion of the Matsuda index. Serum FGF21 levels, however, did not correlate with BMD. CONCLUSION: Among Chinese postmenopausal women, bone quality was worse in IGT, despite comparable bone density. FGF21 levels showed a significant independent inverse relationship with TBS, partly attributed to insulin resistance. Whether FGF21 contributes to the impaired bone quality in IGT remains speculative.


Assuntos
Biomarcadores/metabolismo , Glicemia/análise , Densidade Óssea , Fatores de Crescimento de Fibroblastos/metabolismo , Fraturas Ósseas/patologia , Intolerância à Glucose/complicações , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Estudos Transversais , Feminino , Seguimentos , Fraturas Ósseas/etiologia , Fraturas Ósseas/metabolismo , Teste de Tolerância a Glucose , Humanos , Resistência à Insulina , Pessoa de Meia-Idade , Prognóstico
4.
J Endocrinol Invest ; 43(3): 347-355, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31529391

RESUMO

PURPOSE: Accurate subtyping of the primary aldosteronism into aldosterone-producing adenoma (APA) and idiopathic adrenal hyperplasia (IAH) is important to direct for specific treatment modalities. The objective of the study was to compare the clinical and biochemical parameters of APA and IAH patients to derive a Clinical Prediction Score reliably predicting APA from IAH. METHODS: This was a retrospective multi-centre study recruiting 38 APA patients and 42 IAH patients from four major hospitals in Hong Kong using database from Surgical Outcomes Monitoring and Improvement Programme and Clinical Data Analysis and Reporting System. Their clinical and biochemical parameters were evaluated. RESULTS: Patients in APA group were younger than IAH group (mean age 48.6 ± 9.2 vs. 57.1 ± 7.3 years old, p < 0.001), had more suppressed renin before saline infusion in saline infusion test (SIT) (median 0.19 [IQR 0.15-0.37] vs. 0.39 [IQR 0.19-0.69] ng/mL/h, p = 0.01), and higher aldosterone level after saline infusion in SIT (median 674 [IQR 498-1000] vs. 327 [IQR 242-483] pmol/L, p < 0.001). A clinical prediction score using three parameters was devised, comprising age at diagnosis < 50 years, PRA before saline infusion in SIT ≤ 0.26 ng/mL/h, and aldosterone level after saline infusion in SIT ≥ 424 pmol/L. A score of 2 would predict APA with a sensitivity of 84.2% and specificity of 88.1%, and a score of 3 would predict APA with a sensitivity of 31.6% and specificity of 100%. CONCLUSIONS: Clinical Prediction Score based on the combination of age at diagnosis, PRA, and aldosterone level in the saline infusion tests could reliably predict APA from IAH.


Assuntos
Neoplasias do Córtex Suprarrenal/complicações , Adenoma Adrenocortical/complicações , Aldosterona/sangue , Hiperaldosteronismo/etiologia , Neoplasias do Córtex Suprarrenal/sangue , Adenoma Adrenocortical/sangue , Adulto , Fatores Etários , Feminino , Humanos , Hiperaldosteronismo/sangue , Hiperplasia/complicações , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
5.
Med J Malaysia ; 74(3): 215-218, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31256176

RESUMO

INTRODUCTION: This study was designed to determine the influence of bariatric surgery on changes in the body mass index (BMI), and the control of diabetes, hypertension and dyslipidaemia among obese patients in Malaysia. MATERIALS AND METHODS: This was a retrospective cohort study undertaken at a public tertiary care centre in the state of Perak, Malaysia. Information of obese patients who underwent bariatric surgery was obtained from their medical records. The changes in the BMI, HbA1C, systolic and diastolic blood pressure (SBP and DBP), and lipid levels between three months before and after the surgery were assessed. RESULTS: The patients (n=106) were mostly Malay (66.0%), had at least one comorbidity (61.3%), and had a mean age of 40.38±11.75 years. Following surgery, the BMI of the patients was found to reduce by 9.78±5.82kg/m2. For the patients who had diabetes (n=24) and hypertension (n=47), their mean HbA1C, SBP and DBP were also shown to reduce significantly by 2.02±2.13%, 17.19±16.97mmHg, and 11.45±12.63mmHg, respectively. Meanwhile, the mean total cholesterol, triglyceride and low-density lipoprotein levels of those who had dyslipidaemia (n=21) were, respectively, lowered by 0.91±1.18mmol/L, 0.69±1.11mmol/L and 0.47±0.52mmol/L. CONCLUSION: The findings suggest that in addition to weight reduction, bariatric surgery is helpful in improving the diabetes, hypertension and dyslipidaemia control among obese patients. However, a large-scale trial with a control group is required to verify our findings.


Assuntos
Cirurgia Bariátrica , Diabetes Mellitus/prevenção & controle , Dislipidemias/prevenção & controle , Hipertensão/prevenção & controle , Obesidade/cirurgia , Redução de Peso , Adulto , Índice de Massa Corporal , Doença Crônica , Feminino , Humanos , Malásia , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Estudos Retrospectivos , Resultado do Tratamento
6.
Diabet Med ; 34(9): 1276-1283, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28636749

RESUMO

AIM: To develop models to estimate the direct medical costs associated with diabetes-related complications in the event year and in subsequent years. METHODS: The public direct medical costs associated with 13 diabetes-related complications were estimated among a cohort of 128 353 people with diabetes over 5 years. Private direct medical costs were estimated from a cross-sectional survey among 1825 people with diabetes. We used panel data regression with fixed effects to investigate the impact of each complication on direct medical costs in the event year and subsequent years, adjusting for age and co-existing complications. RESULTS: The expected annual public direct medical cost for the baseline case was US$1,521 (95% CI 1,518 to 1,525) or a 65-year-old person with diabetes without complications. A new lower limb ulcer was associated with the biggest increase, with a multiplier of 9.38 (95% CI 8.49 to 10.37). New end-stage renal disease and stroke increased the annual medical cost by 5.23 (95% CI 4.70 to 5.82) and 5.94 (95% CI 5.79 to 6.10) times, respectively. History of acute myocardial infarction, congestive heart failure, stroke, end-stage renal disease and lower limb ulcer increased the cost by 2-3 times. The expected annual private direct medical cost of the baseline case was US$187 (95% CI 135 to 258) for a 65-year-old man without complications. Heart disease, stroke, sight-threatening diabetic retinopathy and end-stage renal disease increased the private medical costs by 1.5 to 2.5 times. CONCLUSIONS: Wide variations in direct medical cost in event year and subsequent years across different major complications were observed. Input of these data would be essential for economic evaluations of diabetes management programmes.


Assuntos
Complicações do Diabetes/economia , Complicações do Diabetes/epidemiologia , Custos de Cuidados de Saúde , Saúde Pública/economia , Idoso , Estudos Transversais , Angiopatias Diabéticas/economia , Angiopatias Diabéticas/epidemiologia , Nefropatias Diabéticas/economia , Nefropatias Diabéticas/epidemiologia , Retinopatia Diabética/economia , Retinopatia Diabética/epidemiologia , Feminino , Hong Kong/epidemiologia , Humanos , Falência Renal Crônica/economia , Falência Renal Crônica/epidemiologia , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/economia , Infarto do Miocárdio/epidemiologia , Acidente Vascular Cerebral/economia , Acidente Vascular Cerebral/epidemiologia
7.
Osteoporos Int ; 27(5): 1747-54, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26659066

RESUMO

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.


Assuntos
Cálcio/sangue , Diabetes Mellitus Tipo 2/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Diabetes Mellitus Tipo 2/epidemiologia , Hong Kong/epidemiologia , Humanos , Incidência , Pessoa de Meia-Idade , Estudos Observacionais como Assunto , Estudos Retrospectivos , Fatores de Risco , Albumina Sérica/análise , Adulto Jovem
8.
Horm Metab Res ; 47(11): 833-8, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26267327

RESUMO

Identification of germline mutation in patients with apparently sporadic pheochromocytomas and paragangliomas is crucial. Clinical indicators, which include young age, bilateral or multifocal, extra-adrenal, malignant, or recurrent tumors, predict the likelihood of harboring germline mutation in Caucasian subjects. However, data on the prevalence of germline mutation, as well as the applicability of these clinical indicators in Chinese, are lacking. We conducted a cross-sectional study at a single endocrine tertiary referral center in Hong Kong. Subjects with pheochromocytomas and paragangliomas were evaluated for the presence of germline mutations involving 10 susceptibility genes, which included NF1, RET, VHL, SDHA, SDHB, SDHC, SDHD, TMEM 127, MAX, and FH genes. Clinical indicators were assessed for their association with the presence of germline mutations. Germline mutations, 2 being novel, were found in 24.4% of the 41 Chinese subjects recruited and 11.4% among those with apparently sporadic presentation. The increasing number of the afore-mentioned clinical indicators significantly correlated with the likelihood of harboring germline mutation in one of the 10 susceptibility genes. (r=0.757, p=0.026). The presence of 2 or more clinical indicators should prompt genetic testing for germline mutations in Chinese subjects. In conclusion, our study confirmed that a significant proportion of Chinese subjects with apparently sporadic pheochromocytoma and paraganglioma harbored germline mutations and these clinical indicators identified from Caucasians series were also applicable in Chinese subjects. This information will be of clinical relevance in the design of appropriate genetic screening strategies in Chinese populations.


Assuntos
Neoplasias das Glândulas Suprarrenais/genética , Povo Asiático/genética , Predisposição Genética para Doença , Paraganglioma/genética , Feocromocitoma/genética , Adulto , China , Mutação em Linhagem Germinativa/genética , Humanos , Pessoa de Meia-Idade , Curva ROC
9.
Osteoporos Int ; 25(3): 1017-23, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24196720

RESUMO

SUMMARY: A total of 2,266 postmenopausal Chinese women were followed for 4.5 years to determine the incidence of new fractures. The positive predictive value, negative predictive value, sensitivity and specificity of different treatment strategies were compared. Using a fixed optimal threshold calculated from receiver operating characteristics (ROC) curve had the highest sensitivity but lowest specificity. INTRODUCTION: There is no specific intervention threshold based on FRAX to guide treatment for Asian populations. This prospective study sought to determine the impact of applying different intervention thresholds to a cohort of Chinese postmenopausal women. METHODS: This study was part of the Hong Kong Osteoporosis Study. A total of 2,266 treatment-naïve postmenopausal women underwent clinical risk factor and BMD assessments. The subjects were followed to assess fractures. We calculated the FRAX probability of major osteoporotic fractures corresponding to women with prior fractures but no other clinical risk factors. Different treatment strategies which include treating women with prior fractures, women with age-specific FRAX probability corresponding to those with prior fractures, women with osteoporosis as well as women with FRAX probability above a fixed cut-off based on optimizing sensitivity and specificity on the ROC curve were compared. RESULTS: The mean age at baseline was 62.1 ± 8.5 years, and the mean follow-up time was 4.5 ± 2.8 years. One hundred six new major osteoporotic fractures were reported. An optimal (FRAX, with BMD) cut-off point of 9.95 % was identified. All strategies had negative predictive value of >90 %. Using a fixed cut-off had the highest sensitivity (62.3 %) but lowest specificity (73.5 %) and positive predictive value (10.3 %). Using a fixed cut-off would direct treatment from younger women with lower absolute risk to elderly women with higher absolute risk. CONCLUSION: Targeting only women with prior fractures is unlikely to reduce fracture burden. Other treatment strategies with higher sensitivity need to be considered but they have different shortcomings.


Assuntos
Fraturas por Osteoporose/prevenção & controle , Absorciometria de Fóton/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea/fisiologia , Estudos de Coortes , Técnicas de Apoio para a Decisão , Feminino , Hong Kong/epidemiologia , Humanos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/diagnóstico , Osteoporose Pós-Menopausa/epidemiologia , Osteoporose Pós-Menopausa/fisiopatologia , Osteoporose Pós-Menopausa/terapia , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/etiologia , Fraturas por Osteoporose/fisiopatologia , Valor Preditivo dos Testes , Medição de Risco/métodos , Fatores de Risco
10.
Diabet Med ; 30(6): 702-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23432638

RESUMO

AIMS: The receptor for advanced glycation end products (RAGE) plays an important role in the pathogenesis of diabetic complications. RAGE transcript splicing generates a number of isoforms, including a full-length membrane-bound receptor and a soluble isoform, endogenous secretory RAGE (esRAGE). Soluble forms of the receptor (sRAGE) can also be formed by ectodomain shedding of the membrane-associated receptor. We have evaluated serum levels of sRAGE and esRAGE in Chinese patients with Type 1 diabetes and investigated the effect of insulin on the generation of esRAGE and sRAGE in vitro. METHODS: Serum sRAGE and esRAGE were measured by ELISA. The in vitro effect of insulin was investigated by incubating THP-1 macrophages with insulin and RAGE isoforms in cell lysate and conditioned media determined. RESULTS: In patients with diabetes, both serum esRAGE and sRAGE were significantly higher than in age-matched healthy subjects without diabetes. In vitro, insulin increased esRAGE and total RAGE isoform expression in cell lysate on a western blot, and reverse transcription-polymerase chain reaction showed an increase in esRAGE and full-length RAGE mRNA. This was accompanied by an increase in esRAGE and sRAGE in cell conditioned media. Pretreatment of THP-1 cells with a general metalloproteinase inhibitor GM6001 significantly reduced the production of sRAGE, suggesting that insulin also increased the cleavage of full-length cell surface RAGE to form sRAGE. CONCLUSIONS: Chinese patients with Type 1 diabetes have higher serum levels of esRAGE and sRAGE. In vitro, insulin not only increases both full-length RAGE and esRAGE expression, but can also stimulate the shedding of sRAGE from the membrane-bound receptor.


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Receptores Imunológicos/sangue , Regulação para Cima/efeitos dos fármacos , Adulto , Biomarcadores/sangue , Biomarcadores/química , Biomarcadores/metabolismo , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , China , Estudos Transversais , Meios de Cultivo Condicionados/química , Diabetes Mellitus Tipo 1/sangue , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Hipoglicemiantes/farmacologia , Insulina/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Inibidores de Metaloproteinases de Matriz/farmacologia , Pessoa de Meia-Idade , Isoformas de Proteínas/sangue , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismo , Proteólise/efeitos dos fármacos , Receptor para Produtos Finais de Glicação Avançada , Receptores Imunológicos/química , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo , Solubilidade
11.
Neural Comput ; 25(2): 450-72, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23148414

RESUMO

During the past few decades, remarkable progress has been made in solving pattern recognition problems using networks of spiking neurons. However, the issue of pattern recognition involving computational process from sensory encoding to synaptic learning remains underexplored, as most existing models or algorithms target only part of the computational process. Furthermore, many learning algorithms proposed in the literature neglect or pay little attention to sensory information encoding, which makes them incompatible with neural-realistic sensory signals encoded from real-world stimuli. By treating sensory coding and learning as a systematic process, we attempt to build an integrated model based on spiking neural networks (SNNs), which performs sensory neural encoding and supervised learning with precisely timed sequences of spikes. With emerging evidence of precise spike-timing neural activities, the view that information is represented by explicit firing times of action potentials rather than mean firing rates has been receiving increasing attention. The external sensory stimulation is first converted into spatiotemporal patterns using a latency-phase encoding method and subsequently transmitted to the consecutive network for learning. Spiking neurons are trained to reproduce target signals encoded with precisely timed spikes. We show that when a supervised spike-timing-based learning is used, different spatiotemporal patterns are recognized by different spike patterns with a high time precision in milliseconds.


Assuntos
Algoritmos , Modelos Neurológicos , Neurônios/fisiologia , Reconhecimento Fisiológico de Modelo/fisiologia , Animais , Humanos
12.
Osteoporos Int ; 23(7): 1877-87, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22215184

RESUMO

SUMMARY: Periostin (POSTN) as a regulator of osteoblast differentiation and bone formation may affect susceptibility to osteoporosis. This study suggests POSTN as a candidate gene for bone mineral density (BMD) variation and vertebral fracture risk, which could better our understanding about the genetic pathogenesis of osteoporosis and will be useful in clinic in the future. INTRODUCTION: The genetic determination of osteoporosis is complex and ill-defined. Periostin (POSTN), an extracellular matrix secreted by osteoblasts and a regulator of osteoblast differentiation and bone formation, may affect susceptibility to osteoporosis. METHODS: We adopted a tag-single nucleotide polymorphism (SNP) based association method followed by imputation-based verification and identification of a causal variant. The association was investigated in 1,572 subjects with extreme-BMD and replicated in an independent population of 2,509 subjects. BMD was measured by dual X-ray absorptiometry. Vertebral fractures were identified by assessing vertebral height from X-rays of the thoracolumbar spine. Association analyses were performed with PLINK toolset and imputation analyses with MACH software. The top imputation finding was subsequently validated by genotyping. Interactions between POSTN and another BMD-related candidate gene sclerostin (SOST) were analyzed using MDR program and validated by logistical regression analyses. The putative transcription factor binding with target sequence was confirmed by electrophoretic mobility shift assay (EMSA). RESULTS: Several SNPs of POSTN were associated with BMD or vertebral fractures. The most significant polymorphism was rs9547970, located at the -2,327 bp upstream (P = 6.8 × 10(-4)) of POSTN. Carriers of the minor allele G per copy of rs9547970 had 1.33 higher risk of vertebral fracture (P = 0.007). An interactive effect between POSTN and SOST upon BMD variation was suggested (P < 0.01). A specific binding of CDX1 to the sequence of POSTN with the major allele A of rs9547970 but not the variant G allele was confirmed by EMSA. CONCLUSIONS: Our results suggest POSTN as a candidate gene for BMD variation and vertebral fracture risk.


Assuntos
Densidade Óssea/genética , Moléculas de Adesão Celular/genética , Proteínas de Homeodomínio/metabolismo , Fraturas por Osteoporose/genética , Fraturas da Coluna Vertebral/genética , Adulto , Idoso , Sítios de Ligação/genética , Moléculas de Adesão Celular/metabolismo , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Fraturas por Osteoporose/fisiopatologia , Polimorfismo de Nucleotídeo Único , Ligação Proteica/genética , Fraturas da Coluna Vertebral/fisiopatologia
13.
Osteoporos Int ; 23(3): 879-85, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21461720

RESUMO

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.


Assuntos
Fraturas por Osteoporose/etnologia , Fraturas da Coluna Vertebral/etnologia , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Antropometria/métodos , Povo Asiático/estatística & dados numéricos , Feminino , Fraturas do Quadril/etnologia , Hong Kong/epidemiologia , Humanos , Incidência , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Distribuição por Sexo , Suécia/epidemiologia , População Branca/estatística & dados numéricos
14.
Diabetes Obes Metab ; 11(6): 534-43, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19175378

RESUMO

High-density lipoprotein (HDL) plays an important protective role against atherosclerosis, and the anti-atherogenic properties of HDL include the promotion of cellular cholesterol efflux and reverse cholesterol transport (RCT), as well as antioxidant, anti-inflammatory and anticoagulant effects. RCT is a complex pathway, which transports cholesterol from peripheral cells and tissues to the liver for its metabolism and biliary excretion. The major steps in the RCT pathway include the efflux of free cholesterol mediated by cholesterol transporters from cells to the main extracellular acceptor HDL, the conversion of free cholesterol to cholesteryl esters and the subsequent removal of cholesteryl ester in HDL by the liver. The efficiency of RCT is influenced by the mobilization of cellular lipids for efflux and the intravascular remodelling and kinetics of HDL metabolism. Despite the increased cardiovascular risk in people with type 2 diabetes, current knowledge on RCT in diabetes is limited. In this article, abnormalities in RCT in type 2 diabetes mellitus and therapeutic strategies targeting HDL and RCT will be reviewed.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Lipoproteínas HDL/metabolismo , Fígado/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Anticolesterolemiantes/farmacologia , Apolipoproteína A-I/farmacologia , Transporte Biológico , Proteínas de Transferência de Ésteres de Colesterol/antagonistas & inibidores , Ésteres do Colesterol/metabolismo , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Hipolipemiantes/farmacologia , Lipoproteínas HDL/efeitos dos fármacos , Receptores X do Fígado , Camundongos , Niacina/farmacologia , Receptores Nucleares Órfãos/agonistas , Receptores Ativados por Proliferador de Peroxissomo/agonistas , Quinolinas , Coelhos , Receptores Depuradores Classe B/metabolismo , Tiazolidinedionas/farmacologia
15.
Transplant Proc ; 40(8): 2492-3, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18929776

RESUMO

Mortality from acute liver failure (ALF) is high. Live donor liver transplantation (LDLT) is the treatment of choice for ALF in Asia, because cadaveric donors are rare. We sought to review our results in ALF patients with undergoing LDLT at our center. One hundred two LDLTs were performed at our center from April 2002 to November 2007, 15 (14%) because of ALF. Mean (SEM; median, range) follow-up was 1,065 (189; 1400; 3-2046) days. Nine patients (60%) had acute exacerbation of chronic hepatitis B; and 6 (40%) had drug-induced liver injury. Age was 47 (3; 50; 27-65) years. Ten patients (67%) were men. At transplantation, laboratory values were included bilirubin, 449 (35) micromol/L; creatinine concentration, 182 (32) mmol/L. The international normalized ratio was 2.4 (0.2). The Model for End-Stage Liver Disease (MELD) score was 34 (2). Both inpatient and long-term mortality was 20% 3 of 15 patients died. The 5-year survival was 80%. Compared with survivors, patients who died had a significantly higher creatinine concentration 289 vs 155 micromol/L, international normalized ratio (3.4 vs 2.1), MELD score (47 vs 32). We conclude that despite being sick with median and mean MELD scores of 32 and 34, 80% of patients with ALF can achieve good long-term survival after LDLT.


Assuntos
Falência Hepática Aguda/cirurgia , Transplante de Fígado/fisiologia , Doadores Vivos , Adolescente , Adulto , Criança , Pré-Escolar , Creatinina/sangue , Feminino , Humanos , Coeficiente Internacional Normatizado , Fígado/efeitos dos fármacos , Fígado/lesões , Testes de Função Hepática , Transplante de Fígado/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida , Sobreviventes
16.
Transplant Proc ; 40(8): 2507-9, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18929781

RESUMO

Living-donor liver transplantation (LDLT) is an effective treatment for patients with unresectable hepatocellular carcinoma (HCC). However, it remains controversial whether expanded listing criteria can be used for LDLT. We aimed to review results of LDLT for patients with HCC at our center. Patients with HCC were accepted for LDLT if there was no extrahepatic spread on computed tomography (CT) and positron emission tomography CT scan. Transarterial chemoembolization was performed before LDLT to control the tumors. Sirolimus or everolimus was used as part of the immunosuppressive protocol for all patients. Over the last 6 years, 35 of the 102 (34%) LDLT were performed at our center for HCC. Age (mean +/- SEM) was 55.3 +/- 1.3 years; 28 patients (80%) were men. Eight (23%) had LDLT performed in 2002 or 2003 (period 1), and 27 (77%) in 2004 to 2007 (period 2). Eleven (31%) were within and 23 (69%) were outside the Milan criteria. After 583 +/- 76 days follow-up, nine (25%) died, three of recurrent HCC. Three-year survival was significantly better in period 2 than in period 1 (90% vs 13%; P < .001). Although the 3-year survival for those within Milan criteria was better than those outside Milan criteria, the difference did not reach statistical significance (86% vs 57%; P = .26). Six (17%) had HCC recurrence, of whom five died. We concluded that reasonable medium-term survival can be obtained for patients with HCC. The experience level of the transplant team seemed to be the most important predictor of patient outcome.


Assuntos
Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado/estatística & dados numéricos , Doadores Vivos , Equipe de Assistência ao Paciente/normas , Hepatite B Crônica/complicações , Hepatite B Crônica/cirurgia , Hepatite C Crônica/complicações , Hepatite C Crônica/cirurgia , Humanos , Transplante de Fígado/mortalidade , Pessoa de Meia-Idade , Equipe de Assistência ao Paciente/estatística & dados numéricos , Seleção de Pacientes , Período Pós-Operatório , Sobreviventes , Fatores de Tempo
17.
IEEE Trans Syst Man Cybern B Cybern ; 38(3): 808-25, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18558544

RESUMO

Binary representation suffers from the problem of positional dependence, where the amplitude of phenotype variation is dependent on the position of the altered genotype bits. However, this is contrary to conventional variation operations that treat each genotype bit equally. Positional dependence can be attributed to the poor locality, which results in neighboring genotypes having low correlation in the phenotype space, reducing the effectiveness of systematic local search and evolutionary search based on small mutation steps. For this purpose, this paper will propose an alternative genotype-phenotype mapping for binary representation that introduces redundancy into the mapping and removes the exponential orderings between the alleles, hence improving the locality between the genotype and phenotype search space. Empirical study conducted based on distribution, locality, and mutation innovation revealed key algorithmic characteristics of the proposed code, and its practicality is validated by comparative studies based on different benchmark optimization problems. Possible approaches to resolve the overrepresentation problem due to redundancy will be suggested, exhibiting its flexibility and variability in implementation.


Assuntos
Algoritmos , Biomimética/métodos , Modelos Estatísticos , Processamento de Sinais Assistido por Computador , Simulação por Computador
18.
Transplant Proc ; 39(5): 1314-6, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17580129

RESUMO

An 11-year retrospective review (1993 to 2003) of 102 severe burn patients (>40% total body surface area and undergone wound excision surgery) was performed to determine the efficacy of early wound debridement and coverage of large burns with skin allografts, a treatment introduced here in 1998 with the establishment of a skin banking facility. While there was no significant reduction in mortality, length of hospital stay decreased by 15.7 days (P < .05) during the post-skin-banking period. Skin allograft donation rates from multiorgan donors were consistently fewer compared with corneal donation, mainly due to strong cultural beliefs and public misconceptions regarding skin harvesting. The overall tissue donation rate in Singapore may improve if efforts focus on deceased cases sent to the state coroner where retrieval and counseling can be centralized.


Assuntos
Queimaduras/cirurgia , Transplante de Pele/estatística & dados numéricos , Doadores de Tecidos/estatística & dados numéricos , Adolescente , Adulto , Idoso , Cadáver , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Singapura , Transplante Homólogo/estatística & dados numéricos
19.
IEEE Trans Syst Man Cybern B Cybern ; 37(1): 42-50, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17278557

RESUMO

In this paper, a new memetic algorithm (MA) for multiobjective (MO) optimization is proposed, which combines the global search ability of particle swarm optimization with a synchronous local search heuristic for directed local fine-tuning. A new particle updating strategy is proposed based upon the concept of fuzzy global-best to deal with the problem of premature convergence and diversity maintenance within the swarm. The proposed features are examined to show their individual and combined effects in MO optimization. The comparative study shows the effectiveness of the proposed MA, which produces solution sets that are highly competitive in terms of convergence, diversity, and distribution.


Assuntos
Algoritmos , Inteligência Artificial , Comportamento Animal , Biomimética/métodos , Modelos Biológicos , Movimento , Animais , Simulação por Computador , Software , Teoria de Sistemas
20.
Atherosclerosis ; 263: 24-28, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28595104

RESUMO

BACKGROUND AND AIMS: Pre-ß1 HDL, being a major acceptor of free cholesterol from cells, plays an important role in reverse cholesterol transport. This study was performed to determine whether abnormalities in pre-ß1 HDL concentration were present in type 2 diabetes irrespective of their HDL-cholesterol levels, and the impact on cholesterol efflux. METHODS: 640 type 2 diabetic patients with or without cardiovascular disease (CVD) and 360 non-diabetic controls matched for serum HDL-cholesterol levels were recruited. Plasma pre-ß1 HDL was measured by ELISA, and cholesterol efflux to serum, mediated by ATP-binding cassette transporter A1 (ABCA1), was determined by measuring the transfer of [3H]cholesterol from cultured cells expressing ABCA1 to the medium containing the tested serum. RESULTS: Despite the diabetic subjects having matched HDL-cholesterol and total apoA1 as controls, plasma pre-ß1 HDL was significantly reduced in both male (p < 0.01) and female diabetic patients (p < 0.05), and patients with CVD had the lowest pre-ß1 HDL level. Serum capacity to induce ABCA1-mediated cholesterol efflux was impaired in the diabetic group (p < 0.01) and cholesterol efflux correlated with pre-ß1 HDL (Pearson's r = 0.38, p < 0.01), and this association remained significantly even after controlling for age, gender, body mass index, diabetes status, smoking, apoA1, triglyceride and LDL. CONCLUSIONS: Plasma pre-ß1 HDL level was significantly decreased in type 2 diabetes and was associated with a reduction in cholesterol efflux mediated by ABCA1. Our data would suggest that low pre-ß1 HDL might cause impairment in reverse cholesterol transport in type 2 diabetes.


Assuntos
Transportador 1 de Cassete de Ligação de ATP/sangue , HDL-Colesterol/sangue , Diabetes Mellitus Tipo 2/sangue , Lipoproteínas de Alta Densidade Pré-beta/sangue , Adulto , Idoso , Transporte Biológico , Índice de Massa Corporal , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/complicações , Estudos de Coortes , Diabetes Mellitus Tipo 2/complicações , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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