Dynamics of childhood obesity in Hong Kong throughout the COVID-19 pandemic before and after the school closures: a 3-year longitudinal study.

OBJECTIVE: This study is to evaluate if there is any difference in the balance between incidence of and remission from overweight/obesity in Hong Kong school-age children before and during the COVID-19 pandemic over three years. METHODS: This is a retrospective longitudinal study that involved children aged 6-16 years from a database of the School Physical Fitness Award Scheme. RESULTS: 2765 students were longitudinally followed up for two years. The prevalence of childhood overweight/obesity was increased between the 2019 and 2021 academic years (P < 0.001). During the COVID-19 pandemic, the rate of obesity remission significantly reduced by 7.9 % (P = 0.003), at a background of a plateau of obesity among children and adolescents. CONCLUSIONS: Our study provides evidence on the impact of school closure and home confinement as a standard infection control measure for the prevention of COVID-19, which are likely to break the balance between incidence of and remission from childhood obesity.

The view of Hong Kong parents on secondary use of dried blood spots in newborn screening program.

BACKGROUND: Residual dried blood spots (rDBS) from newborn screening programmes represent a valuable resource for medical research, from basic sciences, through clinical to public health. In Hong Kong, there is no legislation for biobanking. Parents' view on the retention and use of residual newborn blood samples could be cultural-specific and is important to consider for biobanking of rDBS. OBJECTIVE: To study the views and concerns on long-term storage and secondary use of rDBS from newborn screening programmes among Hong Kong Chinese parents. METHODS: A mixed-method approach was used to study the views and concerns on long-term storage and secondary use of rDBS from newborn screening programmes among Hong Kong Chinese parents of children 0-3 years or expecting parents through focus groups (8 groups; 33 participants) and a survey (n = 1012, 85% mothers) designed with insights obtained from the focus groups. We used framework analysis to summarise the themes as supportive factors, concerns and critical arguments for retention and secondary use of rDBS from focus group discussion. We used multiple logistic regression to assess factors associated with support for retention and secondary use of rDBS in the survey. RESULTS: Both in focus groups and survey, majority of parents were not aware of the potential secondary use of rDBS. Overall secondary use of rDBS in medical research was well accepted by a large proportion of Hong Kong parents, even if all potential future research could not be specified in a broad consent. However parents were concerned about potential risks of biobanking rDBS including leaking of data and mis-use of genetic information. Parents wanted to be asked for permission before rDBS are stored and mainly did not accept an "opt-out" approach. The survey showed that parents born in mainland China, compared to Hong Kong born parents, had lower awareness of newborn screening but higher support in biobanking rDBS. Higher education was associated with support in rDBS biobanking only among fathers. CONCLUSION: Long-term storage and secondary use of rDBS from newborn screening for biomedical research and a broad consent for biobanking of rDBS are generally acceptable to Hong Kong parents given their autonomy is respected and their privacy is protected, highlighting the importance of an accountable governance and a transparent access policy for rDBS biobanks.

Neonatal mortality in singleton pregnancies: a 20-year retrospective study from a tertiary perinatal unit in Hong Kong.

INTRODUCTION: The global neonatal death (NND) rate has been declining in recent decades, but there are no comprehensive data concerning the characteristics of NNDs in Hong Kong. This study investigated the trends and aetiologies of NNDs among singleton pregnancies in Hong Kong. METHODS: This study included all cases of NND from singleton pregnancies in a tertiary hospital in Hong Kong between 2000 and 2019. The rates, clinical characteristics, and aetiologies of NND were compared between the first (2000-2009) and the second (2010-2019) decades. RESULTS: The NND rate decreased from 1.66/1000 livebirths (97 cases) in the first decade to 1.32/1000 livebirths (87 cases) in the second decade. Congenital or genetic abnormalities (82 cases) caused 44.6% of all NNDs. There was a significant reduction from 0.82/1000 livebirths in the first decade to 0.52/1000 livebirths in the second decade (P=0.037). Other causes of NND were prematurity (69 cases; 37.5%), sepsis (16 cases; 8.7%), hypoxic-ischaemic encephalopathy (15 cases; 8.2%), and sudden infant death syndrome (2 cases; 1.1%). Gestational age-specific neonatal mortality for moderately preterm neonates (31-33 weeks of gestation) significantly decreased from 34.73/1000 in 2000-2009 to 8.63/1000 in 2010-2019 (P=0.001), but there were no significant changes in neonatal mortality for other gestations. CONCLUSION: The NND rate in Hong Kong is among the lowest worldwide. Neonatal deaths in our centre declined over the past two decades, mainly because of improvements in the prenatal diagnosis and treatment of congenital or genetic abnormalities, as well as an improved survival rate among moderately preterm neonates.

Perinatal mortality rate in multiple pregnancies: a 20-year retrospective study from a tertiary obstetric unit in Hong Kong.

INTRODUCTION: Multiple pregnancies have become more common, but their perinatal mortality rate remains higher than the rate among singleton pregnancies. This retrospective study investigated the prevalence and causes of perinatal mortality among multiple pregnancies in Hong Kong. METHODS: All multiple pregnancies in a university tertiary obstetric unit between 2000 and 2019 were reviewed, and the medical records of cases complicated by stillbirth and neonatal death were identified. The causes of perinatal mortality were determined based on clinical assessment and laboratory results, then compared between the first (2000-2009) and second (2010-2019) decades. RESULTS: The prevalence of multiple pregnancies increased from 1.41% in the first decade to 1.91% in the second decade (P<0.001). Compared with the first decade, the second decade had a lower stillbirth rate (14.72 vs 7.68 [both per 1000 births]; P=0.026), late neonatal death rate (4.78 vs 1.16 [both per 1000 livebirths]; P=0.030), and total mortality rate (25.32 vs 13.82 [both per 1000 births]; P=0.006). The decline in stillbirth rate was related to improvements in antenatal care and treatment. The decline in the late neonatal death rate was related to a reduction in preterm birth before 34 weeks (18.5% vs 15.2%; P=0.006), as well as an improvement in the mortality rate in the subgroup of 31-33 weeks (19.23 vs 0 [both per 1000 livebirths]; P=0.035). CONCLUSION: Although the prevalence of multiple pregnancies increased during the study period, the corresponding total perinatal mortality rate improved by 45.4%.

Factors associated with multidisciplinary case conference outcomes in children admitted to a regional hospital in Hong Kong with suspected child abuse: a retrospective case series with internal comparison.

INTRODUCTION: In all cases of suspected child abuse, accurate risk assessment is vital to guide further management. This study examined the relationship between risk factors in a risk assessment matrix and child abuse case conference outcomes. METHODS: Records of all children hospitalised at United Christian Hospital in Hong Kong for suspected child abuse from January 2012 to December 2014 were reviewed. Outcomes of the hospital abuse work-up as concluded in the Multi-Disciplinary Case Conference were categorised as 'established', 'high risk', or 'not established'. All cases of 'established' and 'high risk' were included in the positive case conference outcome group and all cases of 'not established' formed the comparison group. On the other hand, using the Risk Assessment Matrix developed by the California State University, Fresno in 1990, each case was allotted a matrix score of low, intermediate, or high risk in each of 15 matrix domains, and an aggregate matrix score was derived. The effect of individual matrix domain on case conference outcome was analysed. Receiver operating characteristic curve analysis was used to examine the relationship between case conference outcome and aggregate matrix score. RESULTS: In this study, 265 children suspected of being abused were included, with 198 in the positive case conference outcome group and 67 in the comparison group. Three matrix domains (severity and frequency of abuse, location of injuries, and strength of family support systems) were significantly associated with case conference outcome. An aggregate cut-off score of 23 yielded a sensitivity of 91.4% and specificity of 38.2% in relation to outcome of abuse categorisation. CONCLUSIONS: Risk assessment should be performed when handling suspected child abuse cases. A high aggregate score should arouse suspicion in all disciplines managing child abuse cases.

Cleavage of DAP5 by coxsackievirus B3 2A protease facilitates viral replication and enhances apoptosis by altering translation of IRES-containing genes.

Cleavage of eukaryotic translation initiation factor 4G (eIF4G) by enterovirus proteases during infection leads to the shutoff of cellular cap-dependent translation, but does not affect the initiation of cap-independent translation of mRNAs containing an internal ribosome entry site (IRES). Death-associated protein 5 (DAP5), a structural homolog of eIF4G, is a translation initiation factor specific for IRES-containing mRNAs. Coxsackievirus B3 (CVB3) is a positive single-stranded RNA virus and a primary causal agent of human myocarditis. Its RNA genome harbors an IRES within the 5'-untranslated region and is translated by a cap-independent, IRES-driven mechanism. Previously, we have shown that DAP5 is cleaved during CVB3 infection. However, the protease responsible for cleavage, cleavage site and effects on the translation of target genes during CVB3 infection have not been investigated. In the present study, we demonstrated that viral protease 2A but not 3C is responsible for DAP5 cleavage, generating 45- and 52-kDa N- (DAP5-N) and C-terminal (DAP5-C) fragments, respectively. By site-directed mutagenesis, we found that DAP5 is cleaved at amino acid G434. Upon cleavage, DAP5-N largely translocated to the nucleus at the later time points of infection, whereas the DAP5-C largely remained in the cytoplasm. Overexpression of these DAP5 truncates demonstrated that DAP5-N retained the capability of initiating IRES-driven translation of apoptosis-associated p53, but not the prosurvival Bcl-2 (B-cell lymphoma 2) when compared with the full-length DAP5. Similarly, DAP5-N expression promoted CVB3 replication and progeny release; on the other hand, DAP5-C exerted a dominant-negative effect on cap-dependent translation. Taken together, viral protease 2A-mediated cleavage of DAP5 results in the production of two truncates that exert differential effects on protein translation of the IRES-containing genes, leading to enhanced host cell death.

NBR1 is dispensable for PARK2-mediated mitophagy regardless of the presence or absence of SQSTM1.

Degradation of malfunctional mitochondria by mitophagy is a pivotal component of mitochondrial quality control to maintain cellular homeostasis. Mitochondrial clearance through the PINK1/PARK2 pathway is mediated by autophagic adaptor proteins. Previous studies revealed a significant involvement, but not an absolute requirement for SQSTM1 in PARK2-dependent mitophagy, suggesting that the existence of redundant adaptor proteins may compensate for the loss of SQSTM1. Here we investigated whether NBR1, a functional homolog of SQSTM1, has a role in PARK2-mediated mitophagy, either alone or as a compensatory mechanism. We showed that NBR1 does not appear to be required for mitochondrial clustering following mitochondrial depolarization. Moreover, we demonstrated that deletion of NBR1 alone or in combination with SQSTM1 does not prevent the degradation of damaged mitochondria. Our data suggest that NBR1 is dispensable for PARK2-dependent mitophagy and additional autophagic adaptor proteins, other than NBR1, are responsible for mitochondrial degradation in cells depleted of SQSTM1.

Hexokinase 2 controls cellular stress response through localization of an RNA-binding protein.

Subcellular localization of RNA-binding proteins is a key determinant of their ability to control RNA metabolism and cellular stress response. Using an RNAi-based kinome-wide screen, we identified hexokinase 2 (HK2) as a regulator of the cytoplasmic accumulation of hnRNP A1 in response to hypertonic stress and human rhinovirus infection (HRV). We show that inhibition of HK2 expression or pharmacological inhibition of HK2 activity blocks the cytoplasmic accumulation of heterogeneous nuclear ribonucleoprotein A1 (hnRNP A1), restores expression of B-cell lymphoma-extra large (Bcl-xL), and protects cells against hypertonic stress-induced apoptosis. Reduction of HK2 protein levels by knockdown results in decreased HRV replication, a delay in HRV-induced cell death, and a reduced number of infected cells, all of which can be rescued by forced expression of a cytoplasm-restricted hnRNP A1. Our data elucidate a novel role for HK2 in cellular stress response and viral infection that could be exploited for therapeutic intervention.

Cytoplasmic translocation, aggregation, and cleavage of TDP-43 by enteroviral proteases modulate viral pathogenesis.

We have previously demonstrated that infection by coxsackievirus B3 (CVB3), a positive-stranded RNA enterovirus, results in the accumulation of insoluble ubiquitin-protein aggregates, which resembles the common feature of neurodegenerative diseases. The importance of protein aggregation in viral pathogenesis has been recognized; however, the underlying regulatory mechanisms remain ill-defined. Transactive response DNA-binding protein-43 (TDP-43) is an RNA-binding protein that has an essential role in regulating RNA metabolism at multiple levels. Cleavage and cytoplasmic aggregation of TDP-43 serves as a major molecular marker for amyotrophic lateral sclerosis and frontotemporal lobar degeneration and contributes significantly to disease progression. In this study, we reported that TDP-43 is translocated from the nucleus to the cytoplasm during CVB3 infection through the activity of viral protease 2A, followed by the cleavage mediated by viral protease 3C. Cytoplasmic translocation of TDP-43 is accompanied by reduced solubility and increased formation of protein aggregates. The cleavage takes place at amino-acid 327 between glutamine and alanine, resulting in the generation of an N- and C-terminal cleavage fragment of ~35 and ~8 kDa, respectively. The C-terminal product of TDP-43 is unstable and quickly degraded through the proteasome degradation pathway, whereas the N-terminal truncation of TDP-43 acts as a dominant-negative mutant that inhibits the function of native TDP-43 in alternative RNA splicing. Lastly, we demonstrated that knockdown of TDP-43 results in an increase in viral titers, suggesting a protective role for TDP-43 in CVB3 infection. Taken together, our findings suggest a novel model by which cytoplasmic redistribution and cleavage of TDP-43 as a consequence of CVB3 infection disrupts the solubility and transcriptional activity of TDP-43. Our results also reveal a mechanism evolved by enteroviruses to support efficient viral infection.

Does gestational diabetes mellitus affect respiratory outcome in late-preterm infants?

BACKGROUND: Both gestational diabetes mellitus (GDM) and late-preterm delivery at 34-36 weeks' gestation are independently associated with neonatal respiratory complications, but it is unknown whether their combination increases further its risk. We therefore appraised the independent effect of GDM on the respiratory outcome of late-preterm infants. METHODS: In a retrospective cohort study, respiratory outcome of 911 infants delivered at 34-36 weeks' gestation between 1 January 2009 and 30 August 2012 from mothers with GDM (study group, n=130) was compared with infants delivered at the same gestation by mothers without GDM (control group, n=781). RESULTS: The study group had significantly higher incidence of transient tachypnoea of newborn (TTN, p=0.02) and air leak (p=0.012), and required more respiratory support, including oxygen, continuous positive airway pressure (CPAP), mechanical ventilation and neonatal intensive care, with a longer length of hospital stay, but not duration on respiratory support. On logistic regression analysis, GDM is an independent risk factor for TTN (aOR=1.5, 95% C.I.1.0-2.4), CPAP (aOR=2.37, 95% C.I. 1.05-4.89), mechanical ventilation (aOR=4.02 95% C.I. 1.57-10.32) and neonatal intensive care (aOR 1.83, 95% C.I. 1.05-3.87). CONCLUSIONS: Our results demonstrated an independent effect of GDM on the risk of severe respiratory complications in late-preterm infants. Additional close monitoring and timely intervention are necessary in the management of these infants.

Dominant-negative function of the C-terminal fragments of NBR1 and SQSTM1 generated during enteroviral infection.

Coxsackievirus infection induces an abnormal accumulation of ubiquitin aggregates that are generally believed to be noxious to the cells and have a key role in viral pathogenesis. Selective autophagy mediated by autophagy adaptor proteins, including sequestosome 1 (SQSTM1/p62) and neighbor of BRCA1 gene 1 protein (NBR1), are an important pathway for disposing of misfolded/ubiquitin conjugates. We have recently demonstrated that SQSTM1 is cleaved after coxsackievirus infection, resulting in the disruption of SQSTM1 function in selective autophagy. NBR1 is a functional homolog of SQSTM1. In this study, we propose to test whether NBR1 can compensate for the compromise of SQSTM1 after viral infection. Of interest, we found that NBR1 was also cleaved after coxsackievirus infection. This cleavage took place at two sites mediated by virus-encoded protease 2A(pro) and 3C(pro), respectively. In addition to the loss-of-function, we further investigated whether cleavage of SQSTM1/NBR1 leads to the generation of toxic gain-of-function mutants. We showed that the C-terminal fragments of SQSTM1 and NBR1 exhibited a dominant-negative effect against native SQSTM1/NBR1, probably by competing for LC3 and ubiquitin chain binding. Finally, we demonstrated a positive, mutual regulatory relationship between SQSTM1 and NBR1 during viral infection. We showed that knockdown of SQSTM1 resulted in reduced expression of NBR1, whereas overexpression of SQSTM1 led to increased level of NBR1, and vice versa, further excluding the possible compensation of NBR1 for the loss of SQSTM1. Taken together, the findings in this study suggest a novel mechanism through which coxsackievirus infection induces increased accumulation of ubiquitin conjugates and subsequent viral damage.

A biological phantom for evaluation of CT image reconstruction algorithms.

In recent years, iterative algorithms have become popular in diagnostic CT imaging to reduce noise or radiation dose to the patient. The non-linear nature of these algorithms leads to non-linearities in the imaging chain. However, the methods to assess the performance of CT imaging systems were developed assuming the linear process of filtered backprojection (FBP). Those methods may not be suitable any longer when applied to non-linear systems. In order to evaluate the imaging performance, a phantom is typically scanned and the image quality is measured using various indices. For reasons of practicality, cost, and durability, those phantoms often consist of simple water containers with uniform cylinder inserts. However, these phantoms do not represent the rich structure and patterns of real tissue accurately. As a result, the measured image quality or detectability performance for lesions may not reflect the performance on clinical images. The discrepancy between estimated and real performance may be even larger for iterative methods which sometimes produce "plastic-like", patchy images with homogeneous patterns. Consequently, more realistic phantoms should be used to assess the performance of iterative algorithms. We designed and constructed a biological phantom consisting of porcine organs and tissue that models a human abdomen, including liver lesions. We scanned the phantom on a clinical CT scanner and compared basic image quality indices between filtered backprojection and an iterative reconstruction algorithm.

Comparison of Bayesian network and support vector machine models for two-year survival prediction in lung cancer patients treated with radiotherapy.

PURPOSE: Classic statistical and machine learning models such as support vector machines (SVMs) can be used to predict cancer outcome, but often only perform well if all the input variables are known, which is unlikely in the medical domain. Bayesian network (BN) models have a natural ability to reason under uncertainty and might handle missing data better. In this study, the authors hypothesize that a BN model can predict two-year survival in non-small cell lung cancer (NSCLC) patients as accurately as SVM, but will predict survival more accurately when data are missing. METHODS: A BN and SVM model were trained on 322 inoperable NSCLC patients treated with radiotherapy from Maastricht and validated in three independent data sets of 35, 47, and 33 patients from Ghent, Leuven, and Toronto. Missing variables occurred in the data set with only 37, 28, and 24 patients having a complete data set. RESULTS: The BN model structure and parameter learning identified gross tumor volume size, performance status, and number of positive lymph nodes on a PET as prognostic factors for two-year survival. When validated in the full validation set of Ghent, Leuven, and Toronto, the BN model had an AUC of 0.77, 0.72, and 0.70, respectively. A SVM model based on the same variables had an overall worse performance (AUC 0.71, 0.68, and 0.69) especially in the Ghent set, which had the highest percentage of missing the important GTV size data. When only patients with complete data sets were considered, the BN and SVM model performed more alike. CONCLUSIONS: Within the limitations of this study, the hypothesis is supported that BN models are better at handling missing data than SVM models and are therefore more suitable for the medical domain. Future works have to focus on improving the BN performance by including more patients, more variables, and more diversity.

Chorioamnionitis with or without funisitis increases the risk of hypotension in very low birthweight infants on the first postnatal day but not later.

OBJECTIVE: To evaluate the relation between chorioamnionitis and hypotension in very low birthweight infants. METHODS: Retrospective cohort study in infants with a birth weight of <1500 g born between January 2002 and September 2004. The placentas were examined for evidence of chorioamnionitis and funisitis. Hypotension was defined by the use of vasopressors. RESULTS: Of 105 infants, 37 (35%) were chorioamnionitis positive. The onset of hypotension had a skewed distribution: day 1 for 30 episodes and scattered from day 2 to day 19 for the remaining 22. Of the 30 infants who developed hypotension on day 1, 17 (57%) were chorioamnionitis positive. The mean maturity of the chorioamnionitis positive group was 27.91 weeks, marginally less than the mean maturity of 29.05 weeks of the chorioamnionitis negative group (p = 0.05). After adjustment of the effects for confounding variables (birth weight, gestation, surfactant therapy, mechanical ventilation on day 1, high frequency oscillatory ventilation, patent ductus arteriosus), chorioamnionitis was the significant factor in line with hypotension developing on day 1 (adjusted odds ratio 5.14, 95% confidence interval 1.51 to 17.50). There was no evidence that hypotension developing after day 1 was associated with chorioamnionitis. CONCLUSIONS: There is a strong association between chorioamnionitis and hypotension developing on day 1 in very low birthweight infants.

Chorioamnionitis and outcome in extremely preterm infants.

INTRODUCTION: Chorioamnionitis is a risk factor for preterm delivery. Intrauterine infection leads to the fetal inflammatory response which is characterised by elevated cytokine levels. Chorioamnionitis is reported to cause accelerated but abnormal lung maturation, resulting in decreased incidence of respiratory distress syndrome (RDS) but increased chronic lung disease (CLD), and predisposes the infant to cerebral injury. OBJECTIVE: To investigate the relation between chorioamnionitis and RDS, CLD, cerebral lesions, neurodevelopmental outcome and mortality in a cohort of extremely premature infants. MATERIALS AND METHODS: Infants born between 1997 and 2001 with a gestational age of less than 28 weeks or a birth weight of less than 1000 g were divided into two groups: Group 1 with evidence of chorioamnionitis and Group 2 without. Outcomes of these two groups of infants were compared. RESULTS: A total of 388 infants were included (105 in Group 1 and 283 in Group 2). Chorioamnionitis was significantly associated with an increased risk of extreme preterm delivery. Group 1 showed a trend towards an increased incidence of CLD and mortality, while the incidence of periventricular leukomalacia, retinopathy of prematurity (ROP) and necrotising enterocolitis (NEC) were similar between the two groups. Subgroup analysis of 2-year neurodevelopmental outcome showed an increased trend towards cerebral palsy and visual impairment, while the incidence of developmental delay and hearing impairment are similar between the two groups. CONCLUSION: Extremely preterm infants with chorioamnionitis showed a trend towards an increased incidence of CLD, mortality, cerebral palsy and visual impairement, but a decreased risk of RDS.

Simple, quick and efficient site-directed antibody immobilization in a cartridge.

A method is described for the simple, quick and efficient attachment of antibody within a cartridge for use as an immunoaffinity chromatography column. Antibodies are immobilized via their Fc regions through the use of periodate-oxidized carbohydrate functionalities of the immunoglobulin G. The method allows for the in situ coupling of the immunoglobulin G without prior removal of the oxidizing periodate solution. The entire procedure can be completed in 50 minutes. This method is especially useful for quick determinations of a particular monoclonal antibody's functionality or avidity towards a specific antigen. It may also be used in place of a conventional immunoaffinity column for the rapid isolation of small amounts of an antigen. This method will reduce the lengthy process of preparing an immunoaffinity column from several days to less than an hour.

Isolated sphenoiditis: a diagnostic problem.

A case of primary isolated sphenoiditis that developed cavernous sinus thrombosis is presented. It is difficult to diagnose and patients are often not seen initially by an ENT surgeon, making it more important for other branches of medicine to be aware of this condition. We discuss isolated sphenoiditis with particular reference to the diagnosis, management and complications of this condition.