Perspectives and control of hepatitis B virus infection in Taiwan

Hepatitis B virus (HBV) infection is endemic in Taiwan. After the implementation of universal hepatitis B vaccination, there was a significant reduction of hepatitis B surface antigen (HBsAg) seropositivity and HBV-related hepatocellular carcinoma (HCC) incidence in children, teenagers, and young adults. However, the incidence of HBV-related HCC in adults remains high. Through several community- and hospital-based cohort studies, the viral factors affecting the prognosis of HBV carriers have been illustrated. Serum HBV DNA level > 2000 IU/mL at study entry starts to increase the risks of cirrhosis and HCC in adult patients with chronic HBV infection. In addition, serum HBsAg level > 1000 IU/mL is associated with a higher risk of HCC in HBeAg-negative patients with low viral load. Virologically, HBV genotype C/D and core promote/pre-S mutations correlate with an increased HCC risk. Recently, a risk calculator has been developed to predict HCC in noncirrhotic patients with external validation. Therapeutically, hospital-based cohort and population-based nationwide studies indicated that interferon and nucleos(t)ide analogue treatments could reduce the incidence of HCC over time. Towards the ultimate goal of HBV eradication, several novel agents aiming at viral and host targets are under development. In addition, the immune therapy may play a key role in HBV cure in the foreseeable future

Comment on "A special attack on the multiparty quantum secret sharing of secure direct communication using single photons"

In this comment, we show that the special attack [S.-J. Qin, F. Gao, Q.-Y. Wen, F.-C. Zhu, Opt. Commun. 281 (2008) 5472.], which claims to be able to obtain all the transmitted secret message bit values of the protocol of the multiparty quantum secret sharing of secure direct communication using single photons with random phase shift operations, fails. Furthermore, a class of similar attacks are also shown to fail to extract the secrete message.Comment: 2 pages (two-column

Risk stratification of HBV infection in Asia-Pacific region

Hepatitis B virus (HBV) infection is the major etiology of chronic liver disease worldwide and thus a global health problem, especially in Asia-Pacific region. The long-term outcomes of Asian HBV carriers vary widely; however, a significant proportion of them will finally develop end-stage liver disease. Over the past decade, several host and HBV factors predictive of clinical outcomes in Asian HBV carriers have been identified. The community-based REVEAL-HBV study illustrated the strong association between HBV-DNA level at study entry and risk of HCC over time, and male gender, older age, high serum alanine aminotransferase (ALT) level, positive HBeAg, higher HBV-DNA level, HBV genotype C infection and core promoter mutation are independently associated with a higher hepatocellular carcinoma (HCC) risk. Another hospital-based ERADICATE-B cohort further validated the HCC risk started to increase when HBV-DNA level was higher than 2,000 IU/mL. Of particular note, in patients with low viral load (HBV-DNA level <2,000 IU/mL), HBsAg level ≥1,000 IU/mL was a new independent risk factor for HCC. With the results from REVEAL-HBV study, a risk calculator for predicting HCC in adult non-cirrhotic patients has been developed and validated by independent international cohorts (REACH-B). With the combination of HBV-DNA, HBsAg, and ALT levels, ERADICATE-B study proposed an algorithm to predict disease progression and categorize risk levels of HCC as well as corresponding management in Asian HBV carriers. The introduction of transient elastography may further enhance the predictive power. In conclusion, HBsAg level can complement HBV-DNA level for the risk stratification of disease progression in Asian adult patients with chronic HBV infection

Optical properties of Pb(Zr,Ti)O[sub 3] thin films on sapphire prepared by metalorganic decomposition process

[[abstract]]Pb(Zr0.52Ti0.48)O3(PZT) thin films were synthesized on a sapphire substrate for application as planar optical waveguide devices using a metalorganic decomposition (MOD) process. Pyrochlore phase, which always forms preferentially when the PZT thin films (~200 nm) are deposited on a sapphire substrate directly, has been effectively suppressed by using a SrTiO3(STO)film (~190 nm) as a buffer layer. The PZT/sapphire thin films have a significantly larger refractive index than the STO/sapphire ones: n PZT=2.2012 and n STO=2.0639 (at 632.8 nm) by prism coupling measurement and n P'ZT=2.215 and n S'TO=2.084 (at 632.8 nm) by optical transmission spectroscopic measurement. The STO layer cannot only serve as buffer layer for enhancing the crystallization kinetics of the subsequently deposited PZT thin films, but can also serve as cladding layer in a ridge-type planar waveguide, which uses PZT thin film as core materials.[[notice]]補正完畢[[journaltype]]國

Molecular Epidemiology of Hepatitis B Virus

Although safe and effective vaccines for hepatitis B virus (HBV) have been available for nearly three decades, this virus kills at least 600,000 people annually worldwide and remains the leading global cause of chronic hepatitis, cirrhosis, and hepatocellular carcinoma. Because the HBV reverse transcriptase lacks a proofreading function, many HBV genotypes, subgenotypes, mutants, and recombinants exist. At least 10 HBV genotypes (HBV-A through J) with distinct geographic distributions have been identified; by definition, their complete genomic sequences diverge by more than 8%. HBV genotype is increasingly becoming recognized as an important factor in the progression and clinical outcome of HBV-induced disease. Infections by HBV-C or -D are significantly more likely to lead to cirrhosis and hepatocellular carcinoma than are infections by HBV-A or -B. Additionally, the hepatitis B e antigen seroconversion response to standard or pegylated interferon is more favorable in patients with HBV-A or -B than in those with HBV-C or -D. However, therapeutic responses to nucleos(t)ide analogues are generally comparable among HBV genotypes. In conclusion, genotyping of HBV is useful in identifying chronic hepatitis B patients who are at increased risk of disease progression, thereby enabling physicians to optimize antiviral therapy for these patients

Pneumothorax and mortality in the mechanically ventilated SARS patients: a prospective clinical study

INTRODUCTION: Pneumothorax often complicates the management of mechanically ventilated severe acute respiratory syndrome (SARS) patients in the isolation intensive care unit (ICU). We sought to determine whether pneumothoraces are induced by high ventilatory pressure or volume and if they are associated with mortality in mechanically ventilated SARS patients. METHODS: We conducted a prospective, clinical study. Forty-one mechanically ventilated SARS patients were included in our study. All SARS patients were sedated and received mechanical ventilation in the isolation ICU. RESULTS: The mechanically ventilated SARS patients were divided into two groups either with or without pneumothorax. Their demographic data, clinical characteristics, ventilatory variables such as positive end-expiratory pressure, peak inspiratory pressure, mean airway pressure, tidal volume, tidal volume per kilogram, respiratory rate and minute ventilation and the accumulated mortality rate at 30 days after mechanical ventilation were analyzed. There were no statistically significant differences in the pressures and volumes between the two groups, and the mortality was also similar between the groups. However, patients developing pneumothorax during mechanical ventilation frequently expressed higher respiratory rates on admission, and a lower PaO(2)/FiO(2 )ratio and higher PaCO(2 )level during hospitalization compared with those without pneumothorax. CONCLUSION: In our study, the SARS patients who suffered pneumothorax presented as more tachypnic on admission, and more pronounced hypoxemic and hypercapnic during hospitalization. These variables signaled a deterioration in respiratory function and could be indicators of developing pneumothorax during mechanical ventilation in the SARS patients. Meanwhile, meticulous respiratory therapy and monitoring were mandatory in these patients

The Effect of Prenatal Exposure to Radiation on Birth Outcomes: Exploiting a Natural Experiment in Taiwan

We estimate the effect of prenatal exposure to radiation on infant health. By exploiting the 1983 Taiwanese radiation-contaminated buildings (RCBs) accident as a natural experiment, we compare birth outcomes between siblings and cousins exposed to different radiation levels. Given the 1983 accident was unanticipated and exposed cohorts were unaware of the risk until 1992, our design isolates the effect of radiation exposure during pregnancy from other effects. We provide the first evidence that prenatal exposure to a continuous low-level dose of radiation significantly reduces gestational length and increases the probabilities of prematurity and low birth weight