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BACKGROUND: Feeding problems in children with autism jeopardize the well-being of both children with autism and their families. Mixed findings were reported from previous interventions, which were mostly evaluated by single subject research design (SSRD) studies. Moreover, feasibility assessment and social validity measurement were unaddressed by these SSRD studies. To fill this substantial knowledge gap, the present review systematically summarized and evaluated feeding interventions implemented in children with autism, which were assessed by studies employing group designs. METHOD: An extensive literature search in eight established online databases was conducted, and a total of 17 eligible studies published in 2009-2021 were included for further analysis. A descriptive account of the features of the investigations is provided, including assessment of study quality. RESULTS: A total of 449 children with autism and 203 parents/caregivers participated in the included studies. The multiple use of five strategic intervention components were highlighted in this review, including nutrition education/consultations, environmental modifications, sensory exposure, cognitive components, and behaviour interventions. The reviewed interventions showed a preliminarily positive effect for modifying feeding problems in children with autism. Furthermore, the evaluation based on the RE-AIM framework (reach, efficacy, adoption, implementation, and maintenance) demonstrated that an interdisciplinary multi-component intervention strategy may achieve high effectiveness and feasibility in improving feeding problems in a wide range of children with autism. CONCLUSIONS: This review found that interventions achieved and maintained a positive effect on modification of feeding problems in groups of children with autism. Information and gaps identified and summarized in the implementation process may assist both researchers and stakeholders to further support these vulnerable children.
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Transtorno Autístico , Humanos , Criança , Transtorno Autístico/terapia , Transtorno Autístico/psicologia , Projetos de Pesquisa , Transtornos de Alimentação na Infância/terapia , Transtornos de Alimentação na Infância/etiologia , Comportamento Alimentar/psicologia , Pré-EscolarRESUMO
Overweight and obesity have emerged as global health issues among children and adolescents. Restrictions related to the COVID-19 pandemic have aggravated the threat of paediatric obesity due to the prevalent reduction in physical activity (PA) in children and adolescents. However, this has also created an opportunity for healthcare professionals to explore new strategies to address this persistent problem. A systematically conducted scoping review was performed on 15 online databases to summarise and analyse the design, efficacy, and feasibility of PA-based weight management interventions for children and adolescents during the pandemic. Finally, we reviewed 23 eligible studies that were published between 2021 and 2023. The included interventions were presented to 1938 children and adolescents and 355 parents using a virtual or virtually blended face-to-face approach during the pandemic. The intervention design included a basic PA programme with three optional components (nutritional education, sociopsychological counselling, and medication consultations). Implementation generally resulted in favourable changes in body mass index (BMI) and/or body size or composition (primary outcomes), as well as health behaviours, physical health or fitness, and individual well-being (secondary outcomes). A longer duration of exposure to the intervention, female sex, and older age were associated with a higher efficacy of the included interventions. Moreover, the interventions showed high feasibility, with medium-high participant attendance, high acceptance/satisfaction in both children and adolescents and their parents and teachers, and strong participant engagement. This may be related to the high accessibility of health information, timely social support, and enhanced self-efficacy. In conclusion, both the virtual and blended delivery of well-planned weight management interventions during the pandemic show promise for the treatment and control of paediatric obesity. The lessons learned from the pandemic may help improve the design of future interventions and inform the proper integration of new technologies that have emerged in the post-pandemic world.
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COVID-19 , Manejo da Obesidade , Obesidade Infantil , Criança , Humanos , Feminino , Adolescente , Obesidade Infantil/epidemiologia , Obesidade Infantil/prevenção & controle , Pandemias/prevenção & controle , COVID-19/epidemiologia , Exercício FísicoRESUMO
BACKGROUND: The efficacy of structured physical exercise (SPE) has been examined in empirical studies to treat attention deficit hyperactivity disorder (ADHD). This review aimed (i) to systematically review and quantify the effects of SPE on ADHD symptomology and executive function (primary outcomes) and on physical health, physical fitness and mental health issues (secondary outcomes) in children/adolescents with ADHD; (ii) to evaluate the study quality and explore moderation of the effects of SPE; and (iii) to summarize the design of SPE interventions. METHODS: An extensive literature search in the databases of PubMed, Web of Science and EBSCOhost was conducted to identify eligible intervention studies for meta-analysis. A descriptive account of the features of the studies is provided, including assessment of risk/quality (ROB-2/ROBINS-I). Standardized mean difference (SMD) with 95% confidence intervals (CIs) were calculated with random effects models to compare post-intervention effects. RESULTS: A total of 18 studies were included in the review. The majority of the studies examined the effects of SPE lasting for 3-12 weeks. Assessment of bias/quality indicated half of the included studies as high quality. The meta-analysis (pooled n = 627) revealed that SPE had a positive effect on primary and secondary outcomes, that is, inattention (SMD = -1.79), executive function (SMD = 2.19), physical fitness (SMD = 1.39) and mental health issues (SMD = -0.89). Subgroup analysis showed that long-term practice of SPE, featured/tailored SPE, non-Chinese participants, taking methylphenidate and study with low quality had larger effects. CONCLUSIONS: There is emerging evidence that SPE is a promising option to enhance symptom management and physical/mental health in children/adolescents with ADHD.
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Transtorno do Deficit de Atenção com Hiperatividade , Estimulantes do Sistema Nervoso Central , Metilfenidato , Criança , Adolescente , Humanos , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Estimulantes do Sistema Nervoso Central/uso terapêutico , Metilfenidato/uso terapêutico , Exercício Físico , Terapia por ExercícioRESUMO
BACKGROUND: Covid-19 pandemic jeopardized family well-being at the population level internationally. Pandemic-related job/financial difficulties in parents have a spillover effect on their child's well-being and issues of child maltreatment. OBJECTIVE: The current review sought to systematically summarize and analyze this pandemic-related spillover effect. PARTICIPANTS AND SETTINGS: In the home setting, participants involved 11,100 adolescents, 9144 parents/caregivers, and another 7927 parent-children dyads. METHODS: An extensive literature search in 13 electronic databases was conducted. A total 21 eligible papers published from 2020 to 2022 were included for further thematic analysis. RESULTS: A significant positive relationship between the pandemic-related spillover effect from parental job or financial issues to child maltreatment and child's mental/behavioral issues was established. The internal mechanisms demonstrated that this relationship was intermediated or moderated by the interactions of parental mental health issues, parenting practice, and family relationships. Families with particular factors may be more vulnerable and sensitive to the spillover effect during the pandemic. The work-from-home arrangement was found as positively related to enhanced parenting warmth and parent-child relationship in some cases who had relatively high familial social-economic status. CONCLUSIONS: Findings of current review provided the evidences from empirical data. During the Covid-19 pandemic, spillover effect from parental job/financial issues significantly influenced the child well-being and family functioning. Future efforts for intervention/service design should be made to enhance familial protective factors and support those families with vulnerable factors.
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COVID-19 , Maus-Tratos Infantis , Adolescente , Criança , Humanos , Pandemias , Saúde da Criança , Pais/psicologia , Poder Familiar/psicologia , Maus-Tratos Infantis/psicologiaRESUMO
BACKGROUND & AIMS: Recently, a group of hepatologists proposed to rename non-alcoholic fatty liver disease (NAFLD) as metabolic associated fatty liver disease (MAFLD) with modified diagnostic criteria. We aimed to study the impact of the new definition on the epidemiology of fatty liver disease. METHODS: We randomly selected 1013 adults from the Hong Kong census database for clinical assessment, proton-magnetic resonance spectroscopy, and transient elastography. Five hundred sixty-five subjects without fatty liver at baseline underwent follow-up assessment. MAFLD was diagnosed as intrahepatic triglyceride content (IHTG) ≥5% and the presence of overweight/obesity, diabetes, or two other metabolic risk factors, with and without concomitant liver diseases. The diagnosis of NAFLD required the exclusion of concomitant liver diseases; metabolic factors were not considered. RESULTS: The population prevalence of MAFLD and NAFLD was 25.9% (95% CI 23.2-28.7%) and 25.7% (95% CI 23.1-28.5%), respectively. Among 277 subjects with IHTG ≥5%, 247 (89.2%) fulfilled both the definitions of MAFLD and NAFLD. Fourteen subjects (5.1%) had IHTG ≥5% but did not meet the metabolic criteria of MAFLD. The incidence of MAFLD was 2.8 per 100 person-years at a median interval of 47 months (range 34-60 months). Among 78 subjects with incident NAFLD, 59 (75.6%) met the criteria of MAFLD; only one of the latter, a regular drinker, had liver stiffness ≥10 kPa. CONCLUSIONS: The new definition of MAFLD does not significantly change the prevalence compared with NAFLD, but it may reduce the incidence by 25%. People with hepatic steatosis but not fulfilling the definition of MAFLD unlikely have significant liver disease.
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Diabetes Mellitus , Técnicas de Imagem por Elasticidade , Hepatopatia Gordurosa não Alcoólica , Adulto , Humanos , Incidência , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/epidemiologia , PrevalênciaRESUMO
BACKGROUND AND AIM: Hepatitis B core-related antigen (HBcrAg) has been shown to correlate with various viral markers in chronic hepatitis B, but its role in defining natural history is not well studied. We aimed to investigate the use of HBcrAg to define different phases of chronic hepatitis B. METHODS: Stored residual serum samples from longitudinal cohorts of chronic hepatitis B patients in Hong Kong and Japan were studied. Viral markers were measured in three serial serum samples for each patient. Patients were divided into six groups for analysis: hepatitis B e antigen (HBeAg)-positive chronic infection (EPI), HBeAg-positive chronic hepatitis (EPH), HBeAg seroconversion (ES), HBeAg-negative chronic hepatitis (ENH), HBeAg-negative chronic infection (ENI), and HBsAg seroclearance (SS). RESULTS: In total, 166 patients followed up for 100 (76-113) months were included. HBcrAg was correlated with hepatitis B virus DNA and HBsAg levels in both HBeAg-positive and HBeAg-negative patients. HBcrAg cut-off of ≥ 6.0 log U/mL could best differentiate HBeAg-positive from HBeAg-negative patients (area under receiver operating characteristic curve of 0.99, P < 0.001). HBcrAg could not differentiate patients in EPI and EPH phases, but HBcrAg declined dramatically at HBeAg seroconversion. In HBeAg-negative patients, HBcrAg ≥ 4.0 log U/mL could best differentiate ENH from ENI (area under receiver operating characteristic curve of 0.81; P < 0.001), with high specificity (81.6%) but only moderate sensitivity (65.7%) at baseline. Undetectable HBcrAg was found in 17%, 63%, and 89% patients in ENH, ENI, and SS groups at the last visit, respectively. CONCLUSIONS: HBcrAg provides useful information to stage the natural history of chronic hepatitis B, particularly identifying HBeAg-positive patients and HBeAg-negative patients with active disease.
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Antígenos do Núcleo do Vírus da Hepatite B/sangue , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/virologia , Adulto , Biomarcadores/sangue , DNA Viral/imunologia , Feminino , Antígenos de Superfície da Hepatite B/sangue , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Hepatite B Crônica/classificação , Hong Kong , Humanos , Japão , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Adulto JovemRESUMO
BACKGROUND AND AIMS: Type 2 diabetes is an important risk factor for nonalcoholic fatty liver disease (NAFLD) and advanced fibrosis. Current international guidelines recommend the use of noninvasive tests as initial assessments for NAFLD, but the role of noninvasive tests as monitoring tools has not been established. We aimed to study the role of transient elastography as a monitoring tool in patients with type 2 diabetes. APPROACH AND RESULTS: We recruited patients with type 2 diabetes without viral hepatitis or excessive alcohol intake from a complication screening facility in Hong Kong in 2013-2014 and repeated the assessments in 2016-2018. The primary endpoint was an increase of liver stiffness measurement (LSM) to ≥10 kPa. The secondary endpoint was the change in the controlled attenuation parameter (CAP). A total of 611 patients with type 2 diabetes and a valid LSM (mean age, 57.7 ± 10.9 years; 342 men [56.0%]) were included in this study (568 also had a valid CAP). Overall, there was moderate correlation between the baseline and follow-up LSM (r = 0.689, P < 0.001). Among 487 patients with a baseline LSM <10 kPa, 21 (4.3%) had a follow-up LSM ≥10 kPa. Baseline body mass index, alanine aminotransferase (ALT), and ∆ALT were independent factors associated with LSM increase. Among 124 patients with a baseline LSM ≥10 kPa, 70 (56.5%) had a follow-up LSM <10 kPa. Among 198 patients with a CAP <248 dB/m at baseline, 103 (52.0%) had a CAP increased to ≥248 dB/m. CONCLUSIONS: The prevalence and incidence of NAFLD in patients with type 2 diabetes are high. Although advanced fibrosis is common in this population, few patients progress to advanced fibrosis in 3 years. Future studies should define the optimal surveillance interval in patients with diabetes.
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Diabetes Mellitus Tipo 2/complicações , Técnicas de Imagem por Elasticidade/métodos , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Idoso , Alanina Transaminase/sangue , Índice de Massa Corporal , Diabetes Mellitus Tipo 2/diagnóstico por imagem , Feminino , Humanos , Cirrose Hepática/epidemiologia , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/etiologia , Estudos ProspectivosRESUMO
BACKGROUND AND AIM: The Baveno VI Consensus recommends repeating examination in patients with high liver stiffness measurement (LSM) by transient elastography to reduce false-positive diagnosis of advanced liver disease. We tested whether repeating transient elastography can increase the overall diagnostic accuracy. METHODS: Ninety-seven patients with non-alcoholic fatty liver disease who underwent two FibroScan examinations within 6 months prior to liver biopsy were evaluated. An LSM cut-off of 7.9 kPa was used to exclude F3-4 fibrosis. RESULTS: Seventy-eight patients had high LSM at baseline, among whom 27 had low LSM on repeated testing; only four had F3 and none had cirrhosis. In contrast, 31 of 51 patients with high LSM at both examinations had F3-4. Nineteen patients had low LSM at baseline; none of them had F3-4 regardless of the second LSM results. If we took LSM <7.9 kPa at either examination as sufficient to exclude F3-4, the negative predictive value remained high at 91%. The positive predictive value for F3-4 increased from 45% in patients with high LSM at baseline to 61% in those with high LSM at both examinations. Sensitivity analysis using different cut-offs yielded similar results, with 76% of patients with LSM >12 kPa at both examinations having F3-4. CONCLUSIONS: Transient elastography is a highly sensitive screening test to exclude F3-4 fibrosis in non-alcoholic fatty liver disease patients. One-third of patients with high LSM may have normal results on repeated examination. By repeating examination in cases with high LSM, one may spare patients from unnecessary liver biopsy.
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Elasticidade , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/fisiopatologia , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Idoso , Técnicas de Imagem por Elasticidade , Reações Falso-Positivas , Feminino , Humanos , Cirrose Hepática/etiologia , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/complicações , Valor Preditivo dos Testes , Reprodutibilidade dos TestesRESUMO
BACKGROUND & AIMS: Around 10-20% of patients with non-alcoholic fatty liver disease (NAFLD) are non-obese. The benefit of weight reduction in such patients is unclear. We aim to study the efficacy of lifestyle intervention in non-obese patients with NAFLD and to identify factors that predict treatment response. METHODS: A total of 154 community NAFLD patients were randomised to a 12-month lifestyle intervention programme involving regular exercise, or to standard care. The primary outcome was remission of NAFLD at Month 12 by proton-magnetic resonance spectroscopy. After the programme, the patients were prospectively followed until Year 6. The Asian body mass index (BMI) cut-off of 25â¯kg/m2 was used to define non-obese NAFLD. RESULTS: Patients were assigned to the intervention (nâ¯=â¯77) and control (nâ¯=â¯77) groups (39 and 38 in each group had baseline BMI <25 and ≥25â¯kg/m2, respectively). More patients in the intervention group achieved the primary outcome than the control group regardless of baseline BMI (non-obese: 67% vs. 18%, p <0.001; obese: 61% vs. 21%, p <0.001). Lifestyle intervention, lower baseline intrahepatic triglyceride, and reduction in body weight and waist circumference were independent factors associated with remission of NAFLD in non-obese patients. Half of non-obese patients achieved remission of NAFLD with 3-5% weight reduction; the same could only be achieved in obese patients with 7-10% weight reduction. By Year 6, non-obese patients in the intervention group remained more likely to maintain weight reduction and alanine aminotransferase normalisation than the control group. CONCLUSIONS: Lifestyle intervention is effective in treating NAFLD in both non-obese and obese patients. Weight reduction predicts remission of NAFLD in non-obese patients, but a modest weight reduction may be sufficient in this population. LAY SUMMARY: Some patients with non-alcoholic fatty liver disease (NAFLD) are non-obese. The optimal management of such patients is unclear. In this long-term follow-up study of a clinical trial, we show that remission of NAFLD can be achieved in 67% of non-obese patients after lifestyle intervention. The majority of patients can achieve NAFLD remission with modest weight loss of 3-10%. Non-obese patients are also more likely than obese patients to maintain weight reduction and normal liver enzymes in the long run.
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Estilo de Vida , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/terapia , Obesidade/complicações , Indução de Remissão , Adulto , Idoso , Índice de Massa Corporal , Dieta , Exercício Físico , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Método Simples-Cego , Resultado do Tratamento , Triglicerídeos/análise , Circunferência da Cintura , Redução de Peso/fisiologiaRESUMO
BACKGROUND AND AIM: In registration studies, combination therapy of paritaprevir/ritonavir, ombitasvir, and dasabuvir (PrOD) with and without ribavirin for 12-24 weeks can achieve > 90% sustained virological response (SVR) for genotype 1 hepatitis C virus (HCV) infection. However, data in Asia is scanty. We aimed to study the efficacy and safety of this combination therapy in chronic hepatitis C patients in Hong Kong. METHODS: We retrospectively analyzed data from six local hospitals that have prescribed PrOD with and without ribavirin to patients with genotype 1 chronic HCV infection as part of a global compassionate program. RESULTS: Among 41 patients treated, 35 (85%) patients had genotype 1b HCV infection, 6 (15%) had co-infection with human immunodeficiency virus, 35 (85%) failed previous peginterferon and ribavirin therapy, 25 (61%) had compensated liver cirrhosis, and 3 (7%) had liver transplantation. Thirty-five (85%) patients received 12-week treatment and six patients received 24-week treatment; 26 (63%) patients received ribavirin combination. Thirty-nine (95%; 95% confidence interval 88.5-100%) patients had undetectable HCV RNA at 12-week post-treatment, that is, SVR. The two patients who did not develop SVR discontinued treatment prematurely; both of them were treatment experienced with liver cirrhosis complicated by acute renal failure unrelated to the treatment of PrOD and ribavirin. No patient had hepatic decompensation. CONCLUSIONS: Paritaprevir/ritonavir, ombitasvir, and dasabuvir with or without ribavirin is effective and safe in patients with genotype 1 HCV infection in real-life clinical setting in Hong Kong.
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Anilidas/administração & dosagem , Antivirais/administração & dosagem , Carbamatos/administração & dosagem , Hepatite C Crônica/tratamento farmacológico , Compostos Macrocíclicos/administração & dosagem , Ribavirina/administração & dosagem , Ritonavir/administração & dosagem , Sulfonamidas/administração & dosagem , Uracila/análogos & derivados , 2-Naftilamina , Coinfecção , Ciclopropanos , Esquema de Medicação , Quimioterapia Combinada , Genótipo , Infecções por HIV , Hepacivirus/genética , Hepatite C Crônica/virologia , Hong Kong , Lactamas Macrocíclicas , Cirrose Hepática , Transplante de Fígado , Prolina/análogos & derivados , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Uracila/administração & dosagem , ValinaRESUMO
BACKGROUND AND AIM: Controlled attenuation parameter (CAP) evaluated with transient elastography (FibroScan) is a recent method for non-invasive assessment of steatosis. Its usefulness in non-alcoholic fatty liver disease (NAFLD) is unknown. We prospectively investigated the performance of CAP for the diagnosis of steatosis in NAFLD, factors associated with discordances between CAP and steatosis grades, and relationships between CAP and clinical or biological parameters. METHODS: All CAP examinations performed in NAFLD patients with a liver biopsy performed within 1 week of CAP measurement were included. Liver biopsies were assessed for activity and fibrosis stage, NAFLD activity score, and steatosis graded as follows: S0, steatosis < 5%; S1, 5-33%; S2, 34-66%; S3, >66%. RESULTS: Two hundred sixty-one patients (59% male, age 56 years) from two ethnic groups were included. No patient had steatosis < 5%. The area under the receiver-operating characteristics curve of CAP for steatosis ≥S2 and S3 was 0.80 and 0.66, respectively. At a cut-off value of 310 dB/m, the sensitivity, specificity, and positive and negative predictive values for ≥S2 steatosis were 79%, 71%, 86%, and 71%, respectively. Discordance of at least one grade between CAP and steatosis was observed in 81 patients. By multivariate analysis, only steatosis S2S3 was associated with no discordance. By multivariate analysis, only BMI ≥ 30 kg/m(2) was significantly associated with CAP > 310 dB/m. CONCLUSION: The association of CAP with steatosis, especially in patients with non-alcoholic steatohepatitis, and with elevated BMI could be useful for the diagnosis and follow-up of NAFLD patients.
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Técnicas de Imagem por Elasticidade/métodos , Fígado Gorduroso/diagnóstico por imagem , Fígado/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Adulto , Idoso , Biópsia , Índice de Massa Corporal , Fígado Gorduroso/patologia , Feminino , Humanos , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Hepatopatia Gordurosa não Alcoólica/patologia , Valor Preditivo dos Testes , Estudos Prospectivos , Sensibilidade e EspecificidadeRESUMO
BACKGROUND & AIMS: Because abdominal ultrasonography cannot reliably quantify hepatic steatosis, accurate data on the incidence of non-alcoholic fatty liver disease (NAFLD) are lacking. We aimed to study the population incidence of NAFLD with state-of-the-art non-invasive tests. METHODS: This was a prospective cohort study. The intrahepatic triglyceride (IHTG) content was measured serially with proton-magnetic resonance spectroscopy in community subjects. Transient elastography was performed to assess liver fibrosis. RESULTS: 565 subjects (mean age 48 years, 62.7% women) without NAFLD at baseline underwent follow-up assessment after a median interval of 47 months (range 34-60 months). 78 (13.8%) subjects developed incident fatty liver with a mean IHTG content of 8.9% (SD 5.3%). 16 (20.5%) subjects had an IHTG content ⩾ 11.0% suggestive of moderate to severe steatosis. After excluding 2 men with significant alcohol consumption, the population incidence of NAFLD at 3-5 years was 13.5% (95% CI 10.6-16.3%; 3.4% per year). Only 1 subject with incident NAFLD had high liver stiffness (11.1 kPa) suggestive of advanced fibrosis. Metabolic syndrome at baseline was the strongest predictor of incident fatty liver. Incident central obesity developed in 31.0% of subjects with incident fatty liver and 5.6% of those without (p<0.001). No subject with incident fatty liver had regression of impaired fasting glucose, which occurred in 51.1% of those without incident fatty liver (p=0.001). CONCLUSIONS: 13.5% of the Hong Kong Chinese adult population develop NAFLD in 3-5 years, but few have severe steatosis or advanced fibrosis. Metabolic syndrome is the most important risk factor of incident NAFLD.
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Espectroscopia de Ressonância Magnética/métodos , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Vigilância da População , Estudos Transversais , Feminino , Seguimentos , Hong Kong/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Estudos ProspectivosRESUMO
Two unsymmetric bipyridine-platinum(II)-alkynyl complexes have been synthesised by a post-click reaction. These metal complexes are found to exhibit emission enhancement properties. The photoluminescence quantum yield can be significantly increased from 0.03 in solution to 0.72 in solid-state thin films. Efficient solution-processable organic light-emitting diodes have been fabricated by utilizing these complexes as phosphorescent dopants. A high external quantum efficiency of up to 5.8% has been achieved.
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A novel isoquinoline-containing C^N^C ligand and its phosphorescent triphenylamine-based alkynylgold(III) dendrimers have been synthesized. These alkynylgold(III) dendrimers serve as phosphorescent dopants in the fabrication of efficient solution-processable organic light-emitting devices (OLEDs). The photophysical, electrochemical, and electroluminescence properties were studied. A saturated red emission with CIE coordinates of (0.64, 0.36) and a high EQE value of 3.62% were achieved. Unlike other red-light-emitting iridium(III) dendrimers, a low turn-on voltage of less than 3â V and a reduced efficiency roll-off at high current densities were observed; this can be accounted for by the enhanced carrier transporting ability and the relatively short lifetimes in the high-generation dendrimers. This class of alkynylgold(III) dendrimers are promising candidates as phosphorescent dopants in the fabrication of solution-processable OLEDs.
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A series of luminescent multinuclear platinum(II) alkynyl complexes containing triethynylbenzene or 1,4-bis(3,5-diethynylphenyl)buta-1,3-diyne as cores has been successfully synthesized and characterized. The electronic absorption, emission, nanosecond transient absorption and electrochemical properties of these complexes have been reported. These complexes show long-lived emissions in degassed benzene solution and in alcoholic glass at 77 K. Moreover, they are found to exhibit two-photon absorption (2PA) and two-photon induced luminescence (TPIL) properties, and their two-photon absorption cross-sections have been determined to be 6-191 GM upon excitation at 720 nm. Through a systematic comparison, it has been found that tetra- and hexanuclear platinum(II) complexes show better 2PA and TPIL properties than their di- and trinuclear counterparts.
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A series of luminescent platinum(II) alkynyl complexes containing 2,5-diphenyl-1,3,4-oxadiazole (oxa-2,5) and 10,15-dihydro-5H-diindeno[1,2-a;1',2'-c]fluorene (truxene) as the cores and different electron donors at the periphery has been synthesized and characterized. These complexes showed long-lived emissions in both solution and in the solid state at room temperature and have been found to exhibit two-photon absorption (2PA) and two-photon induced luminescence. Their 2PA cross-sections (sigma(2)) have also been determined.