A low-complexity multiscale error diffusion algorithm for digital halftoning

Centre for Multimedia Signal Processing, Department of Electronic and Information EngineeringRefereed conference paper2005-2006 > Academic research: refereed > Refereed conference paperVersion of RecordPublishe

Early detection of neurodegeneration in brain ischemia by manganese-enhanced MRI

This study aims to employ in vivo manganese-enhanced MRI (MEMRI) to detect neurodegenerative changes in two models of brain ischemia, photothrombotic cortical injury (PCI) and transient middle cerebral artery occlusion (MCAO) in rodents. After systemic Mn 2+ injection to both ischemic models, a close pattern of Tl-weighted hyperintensity was observed throughout different brain regions in comparison to the distribution of GFAP, MnSOD and GS immunoreactivities, whereby conventional MRI could hardly detect such. In addition, the infarct volumes in the posterior parts of the brain had significantly reduced after Mn 2+ injection to the MCAO model. It is suggested that exogenous Mn 2+ injection may provide enhanced MEMRI detection of oxidative stress and gliosis early after brain ischemia. Manganese may also mediate infarctions at remote brain regions in transient focal cerebral ischemia before delayed secondary damage takes place. © 2008 IEEE.published_or_final_versionThe 30th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBS) 2008, Vancouver, BC., 20-25 August 2008. in Proceedings of the 30th EMBS, 2008, p. 3884-388

Association of Long-Acting Injectable Antipsychotics and Oral Antipsychotics With Disease Relapse, Health Care Use, and Adverse Events Among People With Schizophrenia

IMPORTANCE: Evidence for improved clinical outcomes with long-acting injectable antipsychotics (LAIAs) vs oral antipsychotics (OAs) is limited in Asian populations and special patient groups, including older people (>65 years), people with substance use, and early initiators of LAIAs. OBJECTIVE: To compare the risk of disease relapse, health care use, and adverse events associated with the use of LAIAs vs OAs among people in Hong Kong with schizophrenia. DESIGN, SETTINGS, AND PARTICIPANTS: In this self-controlled case series study, individuals with a diagnosis of schizophrenia who were prescribed LAIAs and OAs between January 1, 2004, and December 31, 2019, were identified from the Clinical Database Analysis and Reporting System of the Hong Kong Hospital Authority. Data analysis was conducted from May to August in 2021. EXPOSURES: Use of LAIAs vs OAs. MAIN OUTCOMES AND MEASURES: Risk of disease relapse (hospitalizations for psychiatric disorders, hospitalizations for schizophrenia, and suicide attempts), health care use (all-cause emergency department visits and hospitalizations), and adverse events (hospitalizations for somatic disorders, hospitalizations for cardiovascular diseases, and extrapyramidal symptoms) between the period in which patients were treated with LAIAs and the period in which patients were treated with OAs were compared using Poisson regression. RESULTS: Of the 70 396 individuals with schizophrenia (37 200 women [52.8%]; mean [SD] age, 44.2 [15.8] years), 23 719 (33.7%) were prescribed both LAIAs and OAs. Compared with OAs, LAIAs were associated with a lower risk of hospitalizations for any cause (n = 20 973; incidence rate ratio [IRR], 0.63 [95% CI, 0.61-0.65]), hospitalizations for psychiatric disorders (n = 19 283; IRR, 0.52 [95% CI, 0.50-0.53]), hospitalizations for schizophrenia (n = 18 385; IRR, 0.53 [95% CI, 0.51-0.55]), and incident suicide attempts (n = 1453; IRR, 0.56 [95% CI, 0.44-0.71]). During full treatment with LAIAs, there was a reduction in hospitalizations for somatic disorders (n = 15 396; IRR, 0.88 [95% CI, 0.85-0.91]), hospitalizations for cardiovascular diseases (n = 3710; IRR, 0.88 [95% CI, 0.81-0.96]), and extrapyramidal symptoms (n = 22 182; IRR, 0.86 [95% CI, 0.82-0.91]) compared with full treatment with OAs. No significant difference was found for emergency department visits. Similar associations were observed during the subsequent treatment periods (beyond 90 days) and among older people and those with substance use, except for an increased risk of extrapyramidal symptoms among older people when initiating LAIAs (first 90 days). Compared with late initiators, early LAIA initiators had a greater reduction in these outcome events. CONCLUSIONS AND RELEVANCE: This self-controlled case series study of people in Hong Kong with schizophrenia suggests that LAIAs were associated with a lower risk of disease relapse and hospitalization than OAs, without an increased risk of adverse events. Clinicians should more broadly consider the long-term use of LAIAs for Chinese people with schizophrenia, especially early in the course of illness

De novo large rare copy-number variations contribute to conotruncal heart disease in Chinese patients

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Homozygous Missense Mutation in ABR Causes Cerebellar Hypoplasia with Early Lethality - A New Condition Identified by Exome Sequencing?

Poster PresentationWe performed whole exome sequencing (WES) in a consanguineous Pakistani family with a recurrent pattern of cerebellar hyposplasia, intra-uterine growth restriction, and various CNS/non-CNS malformations, resulting in early lethality (1 perinatal death and 1 intrauterine death). Karyotype (in the first pregnancy) and oligonucleotide array (in the 2nd affected pregnancy) were normal. Parents declined post-mortem examination. By WES, a novel homozygous missense mutation was identified in the ABR gene (ABR: NM_021962.4:c.G2455T: p.A819S) in both affected pregnancies. Both parents were identified to be heterozygous of the same mutation while the healthy child did not carry any mutation. The mutation is located in a highly conserved region and is predicted to be highly damaging by all the commonly used in silico mutation prediction tools. The protein encoded by ABR gene contains a GTPase-activating protein domain, a domain found in members of the Rho family of GTP-binding proteins. Previous reports showed that OPHN1, mutations in which cause X-linked mental retardation with cerebellar hypoplasia (OMIM300486), also encodes for a regulator of GTPase-activating protein. Both OPHN1 and ABR are highly expressed in the human brain especially in the cerebellum, and both contain a GTPase-activating domain. Rho proteins are important mediators of intracellular signal transduction, which affects cell migration and cell morphogenesis. Other studies have demonstrated a regulatory role of Rho GTPase in differentiation of cerebellar neurons, and that ethanolassociated impairment of Rho GTPase might contribute to brain defects in fetal alcohol syndrome. Further functional studies, including zebrafish morpholino studies, are currently ongoing. WES can be helpful in individual families with undiagnosed lethal MCA syndromes to identify potentially responsible autosomal recessive mutations and may lead to a better understanding of the role of various developmental pathways in human embryogenesis.published_or_final_versio

Early intervention for psychosis in Hong Kong - the EASY programme

Aim: This article aims to describe the Hong Kong experience in developing and implementing an early psychosis programme. Methods: In 2001, the Early Assessment Service for Young People with Psychosis programme was launched in Hong Kong, providing both educational and service components. Public education includes promotion of timely help-seeking, accessible channels to service and knowledge of psychosis. The 2-year phase-specific intervention includes intensive medical follow-up and individualized psychosocial intervention. The programme has adopted the case-management approach, in which case managers provide protocol-based psychosocial intervention. The programme collaborates with non-governmental organizations and community networks in the provision of rehabilitation service. Results: An average of over 600 young patients enter the programme for intensive treatment each year. Based on preliminary data from a 3-year outcome study, patients in the programme have remarkable reductions in hospital stay accompanied by improvements in vocational functioning. Conclusions: The results suggested that the programme improved patients' outcome. Additional costs such as extra medical staff and medications may be offset by the shortened hospital stay. Further directions in early intervention are also discussed. © 2010 Blackwell Publishing Asia Pty Ltd.postprin

Longitudinal Assessments of Normal and Perilesional Tissues in Focal Brain Ischemia and Partial Optic Nerve Injury with Manganese-enhanced MRI

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CFTR founder mutation causes protein trafficking defects in Chinese patients with cystic fibrosis

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Absence of association between angiotensin converting enzyme polymorphism and development of adult respiratory distress syndrome in patients with severe acute respiratory syndrome: a case control study

BACKGROUND: It has been postulated that genetic predisposition may influence the susceptibility to SARS-coronavirus infection and disease outcomes. A recent study has suggested that the deletion allele (D allele) of the angiotensin converting enzyme (ACE) gene is associated with hypoxemia in SARS patients. Moreover, the ACE D allele has been shown to be more prevalent in patients suffering from adult respiratory distress syndrome (ARDS) in a previous study. Thus, we have investigated the association between ACE insertion/deletion (I/D) polymorphism and the progression to ARDS or requirement of intensive care in SARS patients. METHOD: One hundred and forty genetically unrelated Chinese SARS patients and 326 healthy volunteers were recruited. The ACE I/D genotypes were determined by polymerase chain reaction and agarose gel electrophoresis. RESULTS: There is no significant difference in the genotypic distributions and the allelic frequencies of the ACE I/D polymorphism between the SARS patients and the healthy control subjects. Moreover, there is also no evidence that ACE I/D polymorphism is associated with the progression to ARDS or the requirement of intensive care in the SARS patients. In multivariate logistic analysis, age is the only factor associated with the development of ARDS while age and male sex are independent factors associated with the requirement of intensive care. CONCLUSION: The ACE I/D polymorphism is not directly related to increased susceptibility to SARS-coronavirus infection and is not associated with poor outcomes after SARS-coronavirus infection

Hepatitis B and Renal Disease

Glomerulonephritis is an important extrahepatic manifestation of chronic hepatitis B virus (HBV) infection. The uncommon occurrence, variability in renal histopathology, and heterogeneity in clinical course present challenges in clinical studies and have resulted in a relative paucity of data and uncertainty with regard to the optimal management of HBV-related glomerular diseases. The advent of nucleos(t)ide analogue medications that effectively suppress HBV replication has markedly altered the clinical outcomes of kidney transplant recipients with HBV infection, but the emergence of drug resistance is an escalating problem. This article reviews the recent knowledge of the pathogenesis and treatment of HBV-related membranous nephropathy, and discusses the management of hepatitis B in kidney transplant recipients, which is continuously evolving