683 research outputs found
Theoretical risk assessment of magnesium alloys as degradable biomedical implants
The theoretical tolerable implant masses for ten magnesium alloys as degradable biomedical implant materials are evaluated in this study. Dose-response assessment is conducted using toxicological data from authoritative public health agencies such as the US Agency for Toxic Substances and Disease Registry and the USEPA Integrated Risk Information System, and assuming 1 year of even corrosion. Uncertainty factors adopted by the agencies are used. The tolerable limits corresponding to various component elements in an alloy are considered separately, and the lowest tolerable limit is selected as the tolerable limit of the alloy. The results show that aluminum is usually the component element with the lowest tolerance, and the tolerable mass for Al-containing magnesium alloys fall to around or below 1 g per person per year, while the limit for other magnesium alloys can well exceed 10 g. Deficits in the toxicological data of some component elements are noted. This study illustrates that toxicological calculations should be taken into consideration when developing novel degradable metallic implants. © 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.postprin
HTR4 gene structure and altered expression in the developing lung
Background: Meta-analyses of genome-wide association studies (GWAS) have identified single nucleotide polymorphisms (SNPs) spanning the 5-hydroxytryptamine receptor 4 (5-HT4R) gene (HTR4) associated with lung function. The aims of this study were to i) investigate the expression profile of HTR4 in adult and fetal lung tissue and cultured airway cells, ii) further define HTR4 gene structure and iii) explore the potential functional implications of key SNPs using a bioinformatic approach
A Smart Card-Based Electronic School Absenteeism System for Influenza-Like Illness Surveillance in Hong Kong: Design, Implementation, and Feasibility Assessment
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Minimal residual disease-based risk stratification in Chinese childhood acute lymphoblastic leukemia by flow cytometry and plasma DNA quantitative polymerase chain reaction
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Maternal benzodiazepines and z-drugs use during pregnancy and adverse birth and neurodevelopmental outcomes in offspring: a population-based cohort study
Introduction: The use of benzodiazepines and/or z-drugs in women of childbearing age has increased. /
Objective: To evaluate whether gestational benzodiazepines and/or z-drugs exposure is associated with adverse birth and neurodevelopmental outcomes. /
Methods: A population-based cohort including mother-child pairs from 2001–2018 in Hong Kong was analysed to compared gestationally exposed and nonexposed children on the risk of preterm birth, small for gestational age, autism spectrum disorder (ASD), and attention-deficit/hyperactivity disorder (ADHD) through logistic/Cox proportional hazards regression. Sibling-matched analyses and negative control analyses were applied. /
Results: When comparing gestationally exposed with gestationally nonexposed children, the weighted odds ratio (wOR) was 1.10 (95%CI=0.97–1.25) for preterm birth and 1.03 (95%CI=0.76–1.39) for small for gestational age while the weighted hazard ratio (wHR) was 1.40 (95%CI=1.13–1.73) for ASD and 1.15 (95%CI=0.94–1.40) for ADHD. Sibling-matched analyses showed no association between gestationally exposed children and their gestationally nonexposed siblings for all outcomes (preterm birth: wOR=0.84, 95%CI=0.66–1.06; small for gestational age: wOR=1.02, 95%CI=0.50–2.09; ASD: wHR=1.10, 95%CI=0.70–1.72; ADHD: wHR=1.04, 95%CI=0.57–1.90). Similarly, no significant differences were observed when comparing children whose mothers took benzodiazepines and/or z-drugs during pregnancy to children whose mothers took benzodiazepines and/or z-drugs before but not during pregnancy for all outcomes. /
Conclusions: The findings do not support a causal relationship between gestational benzodiazepines and/or z-drugs exposure and preterm birth, small for gestational age, ASD, or ADHD. Clinicians and pregnant women should carefully balance the known risks of benzodiazepines and/or z-drugs use against that of untreated anxiety and sleep problems
A particle swarm optimization based memetic algorithm for dynamic optimization problems
Copyright @ Springer Science + Business Media B.V. 2010.Recently, there has been an increasing concern from the evolutionary computation community on dynamic optimization problems since many real-world optimization problems are dynamic. This paper investigates a particle swarm optimization (PSO) based memetic algorithm that hybridizes PSO with a local search technique for dynamic optimization problems. Within the framework of the proposed algorithm, a local version of PSO with a ring-shape topology structure is used as the global search operator and a fuzzy cognition local search method is proposed as the local search technique. In addition, a self-organized random immigrants scheme is extended into our proposed algorithm in order to further enhance its exploration capacity for new peaks in the search space. Experimental study over the moving peaks benchmark problem shows that the proposed PSO-based memetic algorithm is robust and adaptable in dynamic environments.This work was supported by the National Nature Science Foundation of China (NSFC) under Grant No. 70431003 and Grant No. 70671020, the National Innovation Research Community Science Foundation of China under
Grant No. 60521003, the National Support Plan of China under Grant No. 2006BAH02A09 and the Ministry of Education, science, and Technology in Korea through the Second-Phase of Brain Korea 21 Project in 2009, the Engineering and Physical Sciences Research
Council (EPSRC) of UK under Grant EP/E060722/01 and the Hong Kong Polytechnic University Research Grants under Grant G-YH60
Association of maternal levothyroxine use during pregnancy with offspring birth and neurodevelopmental outcomes: a population-based cohort study
BACKGROUND: The influence of maternal levothyroxine treatment during pregnancy remains unclear. This study aimed to evaluate the associations of maternal levothyroxine treatment during pregnancy with the birth and neurodevelopmental outcomes in offspring. METHODS: This population-based cohort study was conducted among pregnant women using the Hong Kong Clinical Data Analysis and Reporting System. Mother-child pairs in Hong Kong from 2001 to 2015 were included and children were followed up till 2020. We defined the exposure group as mothers who were exposed to levothyroxine during pregnancy. Preterm birth and small for gestational age (SGA) were included as birth outcomes. Attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) were included as neurodevelopmental outcomes. Odds ratios (OR) or hazard ratios (HRs) with a 95% confidence interval (CI) were evaluated to assess the association of gestational levothyroxine use with offspring birth and neurodevelopmental outcomes respectively, using propensity score fine-stratification weighting and a Cox proportional hazards regression model. RESULTS: Among 422,156 mother-child pairs, 2125 children were born from mothers exposed to levothyroxine during pregnancy. A significantly increased risk of preterm birth was observed in children with maternal levothyroxine exposure during pregnancy, when compared to mothers who had no history of thyroid-related diagnoses or prescriptions (weighted OR [wOR]: 1.22, 95% CI: 1.07, 1.39). Similarly, an increased risk of preterm birth was found among children of gestational levothyroxine users, when compared to children of mothers who had used levothyroxine before but stopped during pregnancy (wOR: 2.16, 95% CI: 1.09, 4.25). Sensitivity analysis, by excluding mothers exposed to psychotropic or antiepileptic medications before or during pregnancy, also indicated a similar increased risk of preterm birth regarding the gestational use of levothyroxine (wOR: 1.26, 95% CI: 1.10, 1.45). No significant association was observed for the risk of SGA, ADHD, and ASD. CONCLUSIONS: There is no evidence that gestational use of levothyroxine is associated with SGA, ADHD, or ASD in offspring. Gestational levothyroxine treatment is associated with a higher risk of preterm birth. Such risk might be confounded by the underlying maternal thyroid disease itself, however, we cannot completely exclude the possible effect of gestational L-T4 treatment on offspring preterm birth. Our findings provided support to the current guidelines on the cautious use of levothyroxine treatment during pregnancy. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12916-022-02586-9
Reduction of covalently closed circular DNA with long-term nucleos(t)ide analogue treatment in chronic hepatitis B
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Mothers' preference and willingness to pay for human papillomavirus vaccination for their daughters: a discrete choice experiment
In Hong Kong, cervical cancer is the seventh
commonest cancer among females and accounts
for about 3.6% of all new cancer cases. To reduce
the disease burden, a cervical cancer screening
programme was launched in 2004 and two vaccines
were introduced in 2006. However, HPV vaccination
is not included in the government immunisation
schedule and is largely taken up in private
clinics opportunistically. The uptake rate of HPV
vaccination among adolescent girls in Hong Kong is
low (2.1%-9.1%).1,2
The success of a HPV vaccination programme
largely depends on the local stakeholders’ attitude
towards risks and benefits of vaccination. Our study
used a discrete choice experiment to elicit Hong
Kong mothers’ preference and willingness to pay
(WTP) for HPV vaccination for their daughters
Intussusception trends in Hong Kong children
OBJECTIVES: To assess trends in intussusception and to validate the coding in Hong Kong's computerised discharge information system. DESIGN: Case notes were reviewed for all children under the age of 5 years who had a discharge diagnosis indicating intussusception or a procedure indicating reduction of intussusception during the 6-year period 1 July 1997 through 30 June 2003. RESULTS: Intussusception rates for infants under 1 year of age (108/100,000) and under 5 years of age (38/100,000) were slightly higher than previous estimates (78-100/100,000 and 27-32/100,000, respectively) that used passive discharge data alone. CONCLUSIONS: Hong Kong's passive computer data systems could be used to monitor rates of intussusception after the introduction of new rotavirus vaccines, provided readmissions, inter-hospital transfers, and hospital follow-ups for the same episode are taken into account.published_or_final_versio
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