Cardiac ion channelopathies encompass a set of inherited or acquired conditions that are due to dysfunction in ion channels or their associated proteins, typically in the presence of structurally normal hearts. They are associated with the development of ventricular arrhythmias and sudden cardiac death. The aim of this review is to provide a historical perspective and recent advances in the research of the cardiac ion channelopathies, Brugada syndrome, long QT syn‑ drome and catecholaminergic polymorphic ventricular tachycardia, in Hong Kong, China. In particular, recent works on the development of novel predictive models incorporating machine learning techniques to improve risk strati‑ fication are outlined. The availability of linked records of affected patients with good longitudinal data in the public sector, together with multidisciplinary collaborations, implies that ion channelopathy research efforts have advanced significantly.

Ventricular arrhythmias (VAs) and sudden cardiac death (SCD) are significant adverse events that affect the morbidity and mortality of both the general population and patients with predisposing cardiovascular risk factors. Currently, conventional disease-specific scores are used for risk stratification purposes. However, these risk scores have several limitations, including variations among validation cohorts, the inclusion of a limited number of predictors while omitting important variables, as well as hidden relationships between predictors. Machine learning (ML) techniques are based on algorithms that describe intervariable relationships. Recent studies have implemented ML techniques to construct models for the prediction of fatal VAs. However, the application of ML study findings is limited by the absence of established frameworks for its implementation, in addition to clinicians’ unfamiliarity with ML techniques.This review, therefore, aims to provide an accessible and easy-to-understand summary of the existing evidence about the use of ML techniques in the prediction of VAs. Our findings suggest that ML algorithms improve arrhythmic prediction performance in different clinical settings. However, it should be emphasized that prospective studies comparing ML algorithms to conventional risk models are needed while a regulatory framework is required prior to their implementation in clinical practice

Cardiovascular diseases are one of the leading global causes of mortality. Currently, clinicians rely on their own analyses or automated analyses of the electrocardiogram (ECG) to obtain a diagnosis. However, both approaches can only include a finite number of predictors and are unable to execute complex analyses. Artificial intelligence (AI) has enabled the introduction of machine and deep learning algorithms to compensate for the existing limitations of cur‑ rent ECG analysis methods, with promising results. However, it should be prudent to recognize that these algorithms also associated with their own unique set of challenges and limitations, such as professional liability, systematic bias, surveillance, cybersecurity, as well as technical and logistical challenges. This review aims to increase familiarity with and awareness of AI algorithms used in ECG diagnosis, and to ultimately inform the interested stakeholders on their potential utility in addressing present clinical challenges.

Background/Aims: Serum fibrosis scores comprised of common laboratory tests have high utility to assess severity of liver fibrosis. We aimed to derive and validate a hepatocellular carcinoma (HCC) risk score based on serum fibrosis scores to predict HCC in treatment-naïve chronic hepatitis B (CHB) patients. Methods: Fifteen thousand one hundred eighty-seven treatment-naïve adult CHB patients were identified to form the training cohort in this retrospective study. Individual fibrosis score was included to construct a new HCC prediction score. The score was externally validated in an independent treatment-naïve Korean CHB cohort. Results: 180/15,187 patients (1.2%) in training cohort and 47/4,286 patients (1.1%) in validation cohort developed HCC during a mean follow-up of 52 and 50 months, respectively. The newly developed HCC risk score, Liang score, is composed of gender, age, hepatitis B virus DNA, fibrosis-4 (FIB-4) index, and ranges from 0 to 22. Area under the time-dependent receiver operating characteristic curve of Liang score was 0.79 (95% confidence interval, 0.70–0.89). A cutoff value of nine provided an extremely high negative predictive value of 99.9% and high sensitivity of 90.0% at 5 years in the validation cohort. Patients with Liang score ≤9 had HCC incidence <0.2% per year in both training and validation cohorts, in whom HCC surveillance might be exempted. Conclusion A novel HCC risk score, Liang score, based on FIB-4 index, is applicable and accurate to identify treatment-naïve CHB patients with very low risk of HCC to be exempted from HCC surveillance.

Erectile Dysfunction/therapy* ; Extracorporeal Shockwave Therapy ; High-Energy Shock Waves ; Humans ; Male ; Singapore

Background/Aims: Serum fibrosis scores comprised of common laboratory tests have high utility to assess severity of liver fibrosis. We aimed to derive and validate a hepatocellular carcinoma (HCC) risk score based on serum fibrosis scores to predict HCC in treatment-naïve chronic hepatitis B (CHB) patients. Methods: Fifteen thousand one hundred eighty-seven treatment-naïve adult CHB patients were identified to form the training cohort in this retrospective study. Individual fibrosis score was included to construct a new HCC prediction score. The score was externally validated in an independent treatment-naïve Korean CHB cohort. Results: 180/15,187 patients (1.2%) in training cohort and 47/4,286 patients (1.1%) in validation cohort developed HCC during a mean follow-up of 52 and 50 months, respectively. The newly developed HCC risk score, Liang score, is composed of gender, age, hepatitis B virus DNA, fibrosis-4 (FIB-4) index, and ranges from 0 to 22. Area under the time-dependent receiver operating characteristic curve of Liang score was 0.79 (95% confidence interval, 0.70–0.89). A cutoff value of nine provided an extremely high negative predictive value of 99.9% and high sensitivity of 90.0% at 5 years in the validation cohort. Patients with Liang score ≤9 had HCC incidence <0.2% per year in both training and validation cohorts, in whom HCC surveillance might be exempted. Conclusion A novel HCC risk score, Liang score, based on FIB-4 index, is applicable and accurate to identify treatment-naïve CHB patients with very low risk of HCC to be exempted from HCC surveillance.

PURPOSE: 83b1 is a novel quinoline derivative that has been shown to inhibit cancer growth in human esophageal squamous cell carcinoma (ESCC). This study was conducted to comprehensively evaluate the cytotoxic effects of 83b1 on a series of ESCC cell lines and investigate the mechanisms by which 83b1 suppresses cancer growth based on molecular docking analysis. MATERIALS AND METHODS: A series of ESCC and nontumor immortalized cell lines were exposed to 83b1 and cisplatin (CDDP) in a dose-dependent manner, and the cytotoxicity was examined by a MTS assay kit. Prediction of the molecular targets of 83b1 was conducted by molecular docking analysis. Expression of cyclooxygenase 2 (COX-2) mRNA and COX-2–derived prostaglandin E₂ (PGE₂) were measured by quantitative real-time polymerase chain reaction and enzymelinked immuno-sorbent assay, respectively. In vivo anti-tumor effect was determined using a nude mice xenografted model transplanted with an ESCC cell line, KYSE-450. RESULTS: 83b1 showed the significant anti-cancer effects on all ESCC cell lines compared to CDDP; however, 83b1 revealed much lower toxic effects on non-tumor cell lines than CDDP. The predicted molecular target of 83b1 is peroxisome proliferator-activated receptor delta (PPARδ), which is a widely known oncoprotein. Additionally the expression of COX-2 mRNA and COX-2–derived PGE2 were down-regulated by 83b1 in a dose-dependent manner in ESCC cell lines. Furthermore, 83b1 was shown to significantly reduce the tumor size in nude mice xenograft. CONCLUSION: The results of this study suggest that the potential anti-cancer effects of 83b1 on human esophageal cancers occur through the possible oncotarget, PPARδ, and down-regulation of the cancer related genes and molecules.
Animals ; Carcinoma, Squamous Cell* ; Cell Line ; Cisplatin ; Cyclooxygenase 2 ; Dinoprostone ; Down-Regulation* ; Epithelial Cells* ; Esophageal Neoplasms ; Heterografts ; Humans* ; Mice ; Mice, Nude ; Molecular Docking Simulation ; PPAR delta ; Quinolines ; Real-Time Polymerase Chain Reaction ; RNA, Messenger*

PURPOSE: The aim of this study was to validate a computational fluid dynamics (CFD) simulation of flow-diverter treatment through Doppler ultrasonography measurements in patient-specific models of intracranial bifurcation and side-wall aneurysms. METHODS: Computational and physical models of patient-specific bifurcation and sidewall aneurysms were constructed from computed tomography angiography with use of stereolithography, a three-dimensional printing technology. Flow dynamics parameters before and after flow-diverter treatment were measured with pulse-wave and color Doppler ultrasonography, and then compared with CFD simulations. RESULTS: CFD simulations showed drastic flow reduction after flow-diverter treatment in both aneurysms. The mean volume flow rate decreased by 90% and 85% for the bifurcation aneurysm and the side-wall aneurysm, respectively. Velocity contour plots from computer simulations before and after flow diversion closely resembled the patterns obtained by color Doppler ultrasonography. CONCLUSION: The CFD estimation of flow reduction in aneurysms treated with a flow-diverting stent was verified by Doppler ultrasonography in patient-specific phantom models of bifurcation and side-wall aneurysms. The combination of CFD and ultrasonography may constitute a feasible and reliable technique in studying the treatment of intracranial aneurysms with flow-diverting stents.
Aneurysm ; Angiography ; Computer Simulation ; Endovascular Procedures ; Hydrodynamics ; Intracranial Aneurysm* ; Stents ; Ultrasonography ; Ultrasonography, Doppler* ; Ultrasonography, Doppler, Color

BACKGROUNDIdentification of hospitalized carbapenem-resistant Enterobacteriaceae (CRE)-positive patient is important in preventing nosocomial transmission. The objective of this study was to illustrate the implementation of proactive infection control measures in preventing nosocomial transmission of CRE in a healthcare region of over 3200 beds in Hong Kong between October 1, 2010 and December 31, 2011.

METHODSThe program included active surveillance culture in patients with history of medical tourism with hospitalization and surgical operation outside Hong Kong within 12 months before admission, and "added test" as an opportunistic CRE screening in all fecal specimens submitted to the laboratory. Outbreak investigation and contact tracing were conducted for CRE-positive patients. Serial quantitative culture was performed on CRE-positive patients and the duration of fecal carriage of CRE was analyzed.

RESULTSDuring the study period, a total of 6533 patients were screened for CRE, of which 76 patients were positive (10 from active surveillance culture, 65 from "added test", and 1 secondary case from contact tracing of 223 patients with no nosocomial outbreak), resulting in an overall rate of CRE fecal carriage of 1.2%. The median time of fecal carriage of CRE was 43 days (range, 13-119 days). Beta-lactam-beta-lactamase-inhibitors, cephalosporins, and fluoroquinolones were associated significantly with high fecal bacterial load when used 90 days before CRE detection, while use of cephalosporins, carbapenems, and fluoroquinolones after CRE detection are significantly associated with longer duration of carriage. The duration of fecal carriage of CRE also correlates significantly with the initial fecal bacterial load (Pearson correlation: 0.53; P = 0.02).

CONCLUSIONProactive infection control measures by enhanced surveillance program identify CRE-positive patients and data obtained are useful for the planning of and resource allocation for CRE control.

Anti-Bacterial Agents ; therapeutic use ; Carbapenems ; therapeutic use ; Cephalosporins ; therapeutic use ; Drug Resistance, Bacterial ; Enterobacteriaceae ; drug effects ; Enterobacteriaceae Infections ; prevention & control ; transmission ; Fluoroquinolones ; therapeutic use ; Humans ; Infection Control ; methods

BACKGROUNDProactive infection control management is crucial in preventing the introduction of multiple drug resistant organisms in the healthcare setting. In Hong Kong, where vancomycin-resistant enterococci (VRE) endemicity is not yet established, contact tracing and screening, together with other infection control measures are essential in limiting intra- and inter-hospital transmission. The objective of this study was to illustrate the control measures used to eradicate a VRE outbreak in a hospital network in Hong Kong.

METHODSWe described an outbreak of VRE in a healthcare region in Hong Kong, involving a University affiliated hospital and a convalescent hospital of 1600 and 550 beds respectively. Computer-assisted analysis was utilized to facilitate contact tracing, followed by VRE screening using chromogenic agar. Multi-locus sequence typing (MLST) was performed to assess the clonality of the VRE strains isolated. A case-control study was conducted to identify the risk factors for nosocomial acquisition of VRE.

RESULTSBetween November 26 and December 17, 2011, 11 patients (1 exogenous case and 10 secondary cases) in two hospitals with VRE colonization were detected during our outbreak investigation and screening for 361 contact patients, resulting in a clinical attack rate of 2.8% (10/361). There were 8 males and 3 females with a median age of 78 years (range, 40 - 87 years). MLST confirmed sequence type ST414 in all isolates. Case-control analysis demonstrated that VRE positive cases had a significantly longer cumulative length of stay (P < 0.001), a higher proportion with chronic cerebral and cardiopulmonary conditions (P = 0.001), underlying malignancies (P < 0.001), and presence of urinary catheter (P < 0.001), wound or ulcer (P < 0.001), and a greater proportion of these patients were receiving β-lactam/β-lactamase inhibitors (P = 0.009), carbapenem group (P < 0.001), fluoroquinolones (P = 0.003), or vancomycin (P = 0.001) when compared with the controls.

CONCLUSIONExtensive contact tracing and screening with a "search-and-confine" strategy was a successful tool for outbreak control in our healthcare region.

Aged ; Aged, 80 and over ; Enterococcus faecium ; growth & development ; pathogenicity ; Female ; Gram-Positive Bacterial Infections ; epidemiology ; prevention & control ; Hong Kong ; epidemiology ; Humans ; Male ; Middle Aged ; Vancomycin Resistance