Percutaneous transhepatic cholangioscopy (PTCS) in management of biliary tract stones: preliminary experience in Tung Wah Hospital

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Mutagenesis and genome engineering of Epstein-Barr virus in cultured human cells by CRISPR/Cas9

The clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR associated protein 9 nuclease (Cas9) system is a powerful genome-editing tool for both chromosomal and extrachromosomal DNA. DNA viruses such as Epstein–Barr virus (EBV), which undergoes episomal replication in human cells, can be effectively edited by CRISPR/Cas9. We have demonstrated targeted editing of the EBV genome by CRISPR/Cas9 in several lines of EBV-infected cells. CRISPR/Cas9-based mutagenesis and genome engineering of EBV provides a new method for genetic analysis, which has some advantages over bacterial artificial chromosome-based recombineering. This approach might also prove useful in the cure of EBV infection. In this chapter, we use the knockout of the BART promoter as an example to detail the experimental procedures for construction of recombinant EBV in human cells.postprin

Harmonic evaluation of traction system by Monte Carlo simulation

This paper presents a method to predict the harmonic current level of traction system with phase-controlled DC Drives by Monte Carlo simulation. Based on Behavioral Modeling Technique (BMT), a model for electrical unit of traction is proposed. The probability density functions (pdf) of speed and notch numbers are obtained from longtime field measurement. The mean and variance of harmonic current of single electrical unit is obtained based on the speed pdf and traction electrical unit model. The results of Monte Carlo simulation are in good accordance with the experimental and analytic conclusions. The harmonics of a different number of trains are systematically investigated. It is shown the Total Harmonic Distortion (THD) decreases with the increase of the number of trains and the harmonic current per train decreases with the train number because of the harmonic cancellation.published_or_final_versio

Modeling of electric railway vehicle for harmonic analysis of traction power-supply system using spline interpolation in frequency domain

It is essential to model nonlinear traction converter loads for harmonic analysis of traction systems. A behavioral model in frequency domain to represent electric railway vehicle based on testing and measurement is proposed for harmonic analysis. The harmonic current characteristics are represented by a set of polynomials generated from cubic smoothing spline interpolation. The purpose of this paper is to report and discuss the development of an electric railway model for harmonic analysis and demonstrate results from the simulation with this train load model. System simulation based on this model is performed and the results match satisfactorily with field measurement.published_or_final_versio

Comparative host gene transcription by microarray analysis early after infection of the Huh7 cell line by SARS coronavirus and human coronavirus 229E

During the early stages of infection, SARS-CoV produces more severe perturbation of host cell gene expression in a human epithelial cell line of liver origin than the HCoV-229E.published_or_final_versio

Adenoviral delivery of RNA decoys restores cellular proapoptotic protein PUMA expression by silencing Epstein-Barr virus-encoded miR-BART5 in nasopharyngeal carcinoma cells

Poster Session 1 - Vaccines and Anti-Viral Therapeutics: no. 3.17Epstein-Barr virus (EBV) encodes 48 mature microRNAs that play important roles in viral maintenance and promote host cell survival by regulating viral transcripts expression, inhibiting apoptosis or facilitating to evade cell immune surveillance. We have previously shown that EBV-encoded miR-BART5 targets and downregulates cellular pro-apoptotic protein p53-upregulated modulator of apoptosis (PUMA) to promote cellular survival of EBV-infected nasopharyngeal carcinoma (NPC) cells. Since compromising miR-BART5 might induce apoptosis of EBV-infected NPC cell, in this study we have established an adenoviral expression system to deliver anti-miR-BART5 decoys to NPC cells. The anti-miR-BART5 decoys comprised 6 tandem repeats of miR-BART5 binding sites and their expression was driven by EBVEBER2 promoter. They were designed to serve as a competitive inhibitor of miR-BART5 to reverse miR-BART5's inhibitory effects on PUMA in EBV-infected NPC cells. The RNA polymerase III-dependent EBER2 promoter is particularly strong in ...postprin

Probabilistic characterization of current harmonics of electrical traction power supply system by analytic method

Current harmonics of an urban railway traction system in Hong Kong are investigated by analytic approach. With the statistic knowledge of speed and notch number of the trains in the system, the mean and variance of harmonic current of individual trains are computed based on a behavior oriented model of the traction electrical unit. According to the Large Number Law and Central Limit Theorem, current harmonics at a substation, which is a vectorial summation of harmonics of random number of trains electrically connected to it, are normally distributed provided that the number of trains is large enough. A set of equations are established by which probability density functions (pdfs) of current harmonics at a substation are calculated and found to be in good accordance with results obtained by Monte Carlo simulation. This approach of harmonics evaluation for traction system with random loading has evident advantages of cheap, fast and convenience and with no compromise of accuracy.published_or_final_versio

Traction system scheduling to minimize harmonic current level at substation by genetic algorithm

Harmonics of individual trains are closely related to its loading, speed and operation mode. The harmonic current at substations is the sum of the individual components from all the trains electrically connected to the substation. There will be cancellation of the harmonics if the harmonics are not of the same phase angles. It is possible to schedule the traction system so as to minimize the harmonic distortion, improve the power factor and reduce the harmonic currents at substations. In this study genetic algorithm (GA) is used to find out the optimal schedule of the system with minimum harmonic levels. The optimized solution can be integrated into automatic train operation (ATO) controller to control the departure, speed regulation of each train of the system. Mathematical description of the problem is first presented and the genetic algorithm is introduced. The optimal solution is given at the end of this paper. It is demonstrated that the scheduling of traction system is applicable to harmonic reduction and GA is fit for such kinds of optimization problems. Such method of harmonics reduction can bring about considerable saving in filtering equipment.published_or_final_versio

BanLec, a banana lectin, is a potent inhibitor of Middle East respiratory syndrome coronavirus in in vitro assays

Poster Abstract Session - Viral Infections: Treatment and Prevention: no. 1159BACKGROUND: Middle East respiratory syndrome coronavirus (MERS-CoV) continues to cause human infections with multiple clusters two years after the onset of the epidemic. Though mild cases have been recognized, the infection is severe in those with co-morbidities and >30% of patients die from the infection. Our recent structure-based development of a fusion inhibitor is one of the few treatment options for MERS and it led us to hypothesize that other existing antivirals that block cellular entry may also be active against MERS-CoV. BanLec is a jacalin-related banana lectin that has potent anti-HIV activity through binding to glycosylated viral envelope proteins and blocking cellular entry. We assessed the anti-MER-CoV activity of BanLec in cell culture assays. METHODS: The anti-MERS-CoV activity of BanLec was assessed by cytopathic effect (CPE) inhibition, viral yield reduction, and plaque reduction (PRA) assays in Vero, Calu-3, and/or HK2 cells. The cytotoxicity of BanLec was also assessed. RESULTS: The CC50 of BanLec was >10 nM in Vero and Calu-3 cells. CPE was completely absent in Vero and HK2 cells infected with MERS-CoV on 3 dpi with 30.00 nM of BanLec. In Calu-3 cells, CPE was completely absent at 90.00 nM of the drug. The EC50 of BanLec ranged from 3.99-4.82 nM (Table 1). The mean viral loads reduced by 7.13, 3.40, and 3.63 log10 copies/ml in Vero, Calu-3, and HK2 cells respectively (Fig. 1A to C). The highest percentage of plaque reduction at a concentration of >10 nM of BanLec were 100% and 59.5% in Vero cells and HK2 cells respectively (Fig. 2A & B). CONCLUSION: BanLec exhibits potent in vitro anti-MERS-CoV activity. The detailed mechanism and in vivo correlation of its antiviral activity should be further tested in animal models. The potential advantages of using BanLec for MERS include its high stability and the prospect of using it as a topical treatment or prophylaxis for exposed patients. (Table see attachment)BACKGROUND: Middle East respiratory syndrome coronavirus (MERS-CoV) continues to cause human infections with multiple clusters two years after the onset of the epidemic. Though mild cases have been recognized, the infection is severe in those with co-morbidities and >30% of patients die from the infection. Our recent structure-based development of a fusion inhibitor is one of the few treatment options for MERS and it led us to hypothesize that other existing antivirals that block cellular entry may also be active against MERS-CoV. BanLec is a jacalin-related banana lectin that has potent anti-HIV activity through binding to glycosylated viral envelope proteins and blocking cellular entry. We assessed the anti-MER-CoV activity of BanLec in cell culture assays. METHODS: The anti-MERS-CoV activity of BanLec was assessed by cytopathic effect (CPE) inhibition, viral yield reduction, and plaque reduction (PRA) assays in Vero, Calu-3, and/or HK2 cells. The cytotoxicity of BanLec was also assessed. RESULTS: The CC50 of BanLec was >10 nM in Vero and Calu-3 cells. CPE was completely absent in Vero and HK2 cells infected with MERS-CoV on 3 dpi with 30.00 nM of BanLec. In Calu-3 cells, CPE was completely absent at 90.00 nM of the drug. The EC50 of BanLec ranged from 3.99-4.82 nM (Table 1). The mean viral loads reduced by 7.13, 3.40, and 3.63 log10 copies/ml in Vero, Calu-3, and HK2 cells respectively (Fig. 1A to C). The highest percentage of plaque reduction at a concentration of >10 nM of BanLec were 100% and 59.5% in Vero cells and HK2 cells respectively (Fig. 2A & B). CONCLUSION: BanLec exhibits potent in vitro anti-MERS-CoV activity. The detailed mechanism and in vivo correlation of its antiviral activity should be further tested in animal models. The potential advantages of using BanLec for MERS include its high stability and the prospect of using it as a topical treatment or prophylaxis for exposed patients

Effect of an advocacy intervention on mental health in Chinese women survivors of intimate partner violence: A randomized controlled trial

Context: Intimate partner violence (IPV) against women can have negative mental health consequences for survivors; however, the effect of interventions designed to improve survivors' depressive symptoms is unclear. Objective: To determine whether an advocacy intervention would improve the depressive symptoms of Chinese women survivors of IPV. Design, Setting, and Participants: Assessor-blinded randomized controlled trial of 200 Chinese women 18 years or older with a history of IPV, conducted from February 2007 to June 2009 in a community center in Hong Kong, China. Intervention: The intervention group (n=100) received a 12-week advocacy intervention comprising empowerment and telephone social support. The control group (n=100) received usual community services including child care, health care and promotion, and recreational programs. Main Outcome Measures: Primary outcome was change in depressive symptoms (Chinese version of the Beck Depression Inventory II) between baseline and 9 months. Secondary outcomes were changes in IPV (Chinese Revised Conflict Tactics Scales), health-related quality of life (12-Item Short Form Health Survey), and perceived social support (Interpersonal Support Evaluation List) between baseline and 9 months. Usefulness of the intervention and usual community services was evaluated at 9 months. Results: At 3 months, themeanchange in depressive symptom score was 11.6(95%CI, 9.5 to 13.7) in the control group and 14.9(95%CI, 12.4 to 17.5) in the intervention group; respective changes at 9 months were 19.6 (95% CI, 16.6 to 22.7) and 23.2 (95% CI, 20.4 to 26.0). Intervention effects at 3 and 9 months were not significantly different (P=.86). The intervention significantly reduced depressive symptoms by 2.66(95%CI, 0.26 to 5.06; P=.03) vs the control, less than the 5-unit minimal clinically important difference. Statistically significant improvement was found in partner psychological aggression (-1.87[95% CI, -3.34 to -0.40]; mean change at 3 months, 1.5 [95% CI, -1.0 to 3.9] in the control group and 0.3 [95% CI, -0.7 to 1.4] in the intervention group; mean change at 9 months, -6.4 [95% CI, -7.8 to -5.0] and -8.9 [95% CI, -10.6 to -7.2]) and perceived social support (2.18[95%CI, 0.48 to 3.89]; meanchange at 3 months, 6.4[95%CI, 4.9 to 7.8] and 9.2 [95% CI, 7.7 to 10.8]; mean change at 9 months, 12.4 [95% CI, 10.5 to 14.3] and 14.4 [95% CI, 12.7 to 16.1]) but not in physical assault, sexual coercion, or health-related quality of life. By end of study, more women in the intervention group found the advocacy intervention useful or extremely useful in improving intimate relationships vs those in the control group receiving usual community services (93.8%vs81.7%;difference,12.1% [95% CI, 2.1% to 22.0%]; P=.02) and in helping them to resolve conflicts with their intimate partners (97.5% vs 84.1%; difference,13.4%[95%CI,4.7%to 22.0%];P=.001). Conclusion: Among community-dwelling abused Chinese women, an advocacy intervention did not result in a clinically meaningful improvement in depressive symptoms. Trial Registration: clinicaltrials.gov Identifier: NCT01054898. ©2010 American Medical Association. All rights reserved.postprin