Pre-primary education in Hong Kong : the evolution of governance and policy tools

published_or_final_versionPolitics and Public AdministrationMasterMaster of Public Administratio

Gametogenesis, Embryogenesis, and Fertilization Ecology of Platygyra acuta

Understanding the reproductive biology of dominant coral species in subtropical nonreefal coral communities is critical in providing important information on the processes underlying the distribution limits of coral species and communities. This is the first study that investigates the reproduction cycle, gametogenesis, and fertilization ecology of Platygyra acuta. Results indicated that P. acuta is hermaphroditic and exhibits a single annual gametogenic cycle. Oogenic and spermatogenic cycle occurs for 6-7 months and for 2 months, respectively, prior to annual mass spawning event in May to June in Hong Kong. It took 18 hours for P. acuta to complete embryonic development, develop cilia, and start to rotate. High (>70%) fertilization success can be achieved under a broad range of sperm concentrations from 104 to 107 sperms mL−1. Fertilization success remained consistently high 6 h after spawning, indicating a prolonged viability of its gametes that is much longer than that recorded for other coral species. Significantly higher percentage of fertilization success was recorded in the first of the two consecutive nights of spawning, suggesting differences in the quality of the eggs and/or sperms between days of spawning. These results serve as important baseline information for better understanding of corals in marginal communities

The Spill-Over Impact of the Novel Coronavirus-19 Pandemic on Medical Care and Disease Outcomes in Non-communicable Diseases: A Narrative Review

OBJECTIVES: The coronavirus-19 (COVID-19) pandemic has claimed more than 5 million lives worldwide by November 2021. Implementation of lockdown measures, reallocation of medical resources, compounded by the reluctance to seek help, makes it exceptionally challenging for people with non-communicable diseases (NCD) to manage their diseases. This review evaluates the spill-over impact of the COVID-19 pandemic on people with NCDs including cardiovascular diseases, cancer, diabetes mellitus, chronic respiratory disease, chronic kidney disease, dementia, mental health disorders, and musculoskeletal disorders. METHODS: Literature published in English was identified from PubMed and medRxiv from January 1, 2019 to November 30, 2020. A total of 119 articles were selected from 6,546 publications found. RESULTS: The reduction of in-person care, screening procedures, delays in diagnosis, treatment, and social distancing policies have unanimously led to undesirable impacts on both physical and psychological health of NCD patients. This is projected to contribute to more excess deaths in the future. CONCLUSION: The spill-over impact of COVID-19 on patients with NCD is just beginning to unravel, extra efforts must be taken for planning the resumption of NCD healthcare services post-pandemic

Carboxyl-terminal truncated HBx regulates a distinct microRNA transcription program in Hepatocellular carcinoma development

Background: The biological pathways and functional properties by which misexpressed microRNAs (miRNAs) contribute to liver carcinogenesis have been intensively investigated. However, little is known about the upstream mechanisms that deregulate miRNA expressions in this process. In hepatocellular carcinoma (HCC), hepatitis B virus (HBV) X protein (HBx), a transcriptional trans-activator, is frequently expressed in truncated form without carboxyl-terminus but its role in miRNA expression and HCC development is unclear. Methods: Human non-tumorigenic hepatocytes were infected with lentivirus-expressing full-length and carboxyl-terminal truncated HBx (Ct-HBx) for cell growth assay and miRNA profiling. Chromatin immunoprecipitation microarray was performed to identify the miRNA promoters directly associated with HBx. Direct transcriptional control was verified by luciferase reporter assay. The differential miRNA expressions were further validated in a cohort of HBV-associated HCC tissues using real-time PCR. Results: Hepatocytes expressing Ct-HBx grew significantly faster than the full-length HBx counterparts. Ct-HBx decreased while full-length HBx increased the expression of a set of miRNAs with growth-suppressive functions. Interestingly, Ct-HBx bound to and inhibited the transcriptional activity of some of these miRNA promoters. Notably, some of the examined repressed-miRNAs (miR-26a, -29c, -146a and -190) were also significantly down-regulated in a subset of HCC tissues with carboxyl-terminal HBx truncation compared to their matching non-tumor tissues, highlighting the clinical relevance of our data. Conclusion: Our results suggest that Ct-HBx directly regulates miRNA transcription and in turn promotes hepatocellular proliferation, thus revealing a viral contribution of miRNA deregulation during hepatocarcinogenesis. © 2011 Yip et al.published_or_final_versio

Human germline heterozygous gain-of-function STAT6 variants cause severe allergic disease

STAT6 (signal transducer and activator of transcription 6) is a transcription factor that plays a central role in the pathophysiology of allergic inflammation. We have identified 16 patients from 10 families spanning three continents with a profound phenotype of early-life onset allergic immune dysregulation, widespread treatment-resistant atopic dermatitis, hypereosinophilia with esosinophilic gastrointestinal disease, asthma, elevated serum IgE, IgE-mediated food allergies, and anaphylaxis. The cases were either sporadic (seven kindreds) or followed an autosomal dominant inheritance pattern (three kindreds). All patients carried monoallelic rare variants in STAT6 and functional studies established their gain-of-function (GOF) phenotype with sustained STAT6 phosphorylation, increased STAT6 target gene expression, and TH2 skewing. Precision treatment with the anti-IL-4Rα antibody, dupilumab, was highly effective improving both clinical manifestations and immunological biomarkers. This study identifies heterozygous GOF variants in STAT6 as a novel autosomal dominant allergic disorder. We anticipate that our discovery of multiple kindreds with germline STAT6 GOF variants will facilitate the recognition of more affected individuals and the full definition of this new primary atopic disorder

Influence of membrane chemistry on transport property

MFI-type zeolites with their three-dimensional channel network are strong candidate materials for separation of straight chain and aromatic hydrocarbons. They have captured the main focus in the research area of zeolite membranes. High permselectivity has been observed in the separations of gases, close-boiling hydrocarbons, along with butane and xylene isomers using MFI zeolite membranes. Recently, the influence of membrane microstructure (i.e. membrane thickness, grain size, morphology and film orientation) on gas permeation properties of MFI-type membranes has been reported. It is noted that membrane chemistry also plays an important role on the transport properties of the membrane. The objectives of this study are to investigate the effects of membrane chemistry and low temperature templates removal methods on the permeation properties of MFI zeolite membranes. Supported zeolite membranes with engineered microstructure and tailored chemistry were prepared using a novel synthesis method. This technique involved seeding of colloidal zeolites on the substrate followed by hydrothermal synthesis to minimize inter-crystalline porosity. Applying different membrane growth sequence, the non-uniform spatial distribution of framework ion, aluminum, ZSM-5 membrane was located at different positions of the 3-layer MFI membranes could be tailored/optimized. The results were illustrated that the gas permeance was independent of the uniform and non-uniform spatial distribution of aluminum along the membrane thickness. The three-layers, non-uniform spatial distribution of aluminum MFI membranes showed a comparable gas permeance and separation behavior to the uniform single layer aluminum distributed MFI membrane. However, the permselectivity of butane isomers is sensitive to the aluminum content in the membrane. Higher permselectivity of butane isomers is observed in aluminum rich ZSM-5 membrane when compared with silicon rich Silicalite-1 membrane. Consecutive ion exchanges with different ions were carried out successfully on the same ZSM-5 membrane. The permeation behavior of ion-exchanged ZSM-5 exhibited a strong dependency on the substituted counterions. The presence of larger counterions led to slower gas permeance. The n-butane/iso-butane ideal selectivity varied with different size of the substituted counterions in ZSM-5 membrane The substrate used also affected the selectivity of zeolite membrane. MFI zeolite membrane grown on porous γ-alumina support selectively separated hydrogen from a commercial fuel mixture (i.e., Towngas: 49.7 % H2, 27.7 % CH4, 19.5 % CO2 and 3.1% CO) whereas MFI membrane grown on porous α-alumina support preferentially separated CH4 and CO2. The ideal separation of butane isomers was different when using porous γ-alumina and α-alumina support membranes. In addition to the membrane chemistry and microstructure, the removal of organic templates from zeolite pores after the membrane synthesis also affected the transport properties of zeolite membrane. In this study, stepwise oxygen plasma method and ozone treatment at low temperature were used instead of traditional air calcination at high temperature. The pemeance of permanent gases (i.e., He, H2, N2 and Ar) and hydrocarbons (i.e., CH4, n-butane and iso-butane) displayed a strong dependence on the extent of removal of organic templates in zeolite pore and method used

Use of Miniplates and Local Bone Grafts to Prevent Spring Back in Laminoplasty for Cervical Spondylotic Myelopathy

Background/Purpose: Cervical spondylotic myelopathy/ossification of posterior longitudinal ligament can be treated by anterior or posterior decompression. For multiple levels, it is common to perform posterior decompression by laminoplasty. Hirabayashi described his open-door expansive laminoplasty in 1977, which soon became popular. Spring back of the lamina has always been a problem. Many methods including suturing to soft tissue, suture anchors, bone grafts, hydroxyapatite blocks, and ceramic spacers were used to prevent this problem, but with considerable failure. Recently, miniplates were used to prevent spring back. Methods: Twenty-nine consecutive patients who had underwent Hirabayashi open-door expansive laminoplasty in a single centre were recruited in this retrospective study. Miniplates were used to keep the laminae open. In addition, the spinous processes of lower cervical vertebrae were excised and used as local bone grafts to fill the gap between the cut laminae. Computerized tomography scans were performed postoperatively for all patients to assess bone union and spring back. Results: A total of 126 levels of laminoplasty and 51 local bone grafts were studied. The minimal follow-up period was 12 months. Signs of bone union were demonstrated in 123 hinges (97.6%) and 51 bone grafts (100%). No spring back was detected. The clinical outcome in terms of Hirabayashi recovery rate was 47.2%. Conclusion: Miniplates and local bone grafts are promising and effective tools for preventing spring back in cervical laminoplasty

Complete Genome Sequence of Staphylococcus lugdunensis Strain HKU09-01▿

Staphylococcus lugdunensis is a member of the coagulase-negative staphylococci and commonly found as part of the human skin flora. It is a significant cause of catheter-related bacteremia and also causes serious infections like native valve endocarditis in previously healthy individuals. We report the complete genome sequence of this medically important bacterium