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Dive into the research topics where He-Jun Yuan is active.

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Featured researches published by He-Jun Yuan.


Gut | 2005

Prognostic determinants for chronic hepatitis B in Asians: therapeutic implications.

M.-F. Yuen; He-Jun Yuan; Danny Ka-Ho Wong; John Chi-Hang Yuen; Wm Wong; Aoo Chan; B. C. Y. Wong; Kc Lai; Ching-Lung Lai

Background: Identifying risk factors for the development of complications of chronic hepatitis B (CHB) is important for setting up treatment criteria. Aim: To determine risk factors for the development of complications in Asian CHB patients. Patients and methods: A total of 3233 Chinese CHB patients (mean follow up 46.8 months) were monitored for liver biochemistry, viral serology, hepatitis B virus (HBV) DNA levels, acute exacerbation, hepatitis B e antigen (HBeAg) seroconversion, and development of cirrhotic complications and hepatocellular carcinoma. Results: Median age for HBeAg seroconversion and development of complications was 35 years and 57.2 years, respectively. Patients with alanine aminotransferase (ALT) levels of 0.5–1 times the upper limit of normal (ULN) and 1–2× ULN had an increased risk for the development of complications compared with patients with ALT levels <0.5× ULN (p<0.0001 for both). HBeAg/antibody to hepatitis B e antigen status, and number of episodes, duration, and peak ALT levels of acute exacerbations were not associated with an increased risk of complications. In patients with complications, 43.6% had HBV DNA levels less than 1.42×105 copies/ml. Male sex, stigmata of chronic liver disease, old age, low albumin, and high α fetoprotein levels on presentation were independently associated with increased cumulative risk of complications. Male sex, presence of hepatitis symptoms, old age, low albumin level, and presence of complications on presentation were independently associated with shorter survival. Conclusion: Prolonged low level viraemia causing insidious and continual liver damage, as reflected by ALT levels of 0.5–2× ULN, is the most likely pathway for the development of complications in Asian CHB patients.


Hepatology | 2004

HBsAg seroclearance in chronic hepatitis B in the Chinese: Virological, histological, and clinical aspects

Man-Fung Yuen; Danny Ka-Ho Wong; Erwin Sablon; Eric Tse; Irene Oi-Lin Ng; He-Jun Yuan; Chung-Wah Siu; Tamara J. Sander; Eric J. Bourne; Jeff Hall; Lynn D. Condreay; Ching-Lung Lai

Few studies have examined Chinese patients with chronic hepatitis B who exhibit hepatitis B surface antigen (HBsAg) seroclearance. We comprehensively studied the biochemical, virological, histological, and clinical aspects of 92 patients with HBsAg seroclearance (median follow‐up, 126 months). Ninety‐two HBsAg‐positive controls matched for age, sex, and duration of follow‐up were also recruited. Liver biochemistry, serum hepatitis B virus (HBV) DNA levels, and development of clinical complications were monitored. Intrahepatic total and covalently closed circular (ccc) HBV DNA were measured quantitatively in 16 patients. HBV genotype was determined in 30 patients. The mean age at HBsAg seroclearance was 48.8 (+ 13.81) years. There was a significant improvement in serum alanine aminotransferase levels after HBsAg seroclearance (p<0.0001). Patients with genotype B had a higher chance of HBsAg seroclearance than those with genotype C (P = .014). Ninety‐eight percent of patients had undetectable serum HBV DNA. Thirty‐seven percent of patients had low titer of intrahepatic HBV DNA, mainly in the form of cccDNA (71%‐100%). All 14 patients with liver biopsies had near normal histology. There was no difference in the risk of development of hepatocellular carcinoma (HCC) between patients with and without HBsAg seroclearance. However, the mean age of HBsAg seroclearance was significantly older in patients with HCC than in patients without HCC (P = .016). In conclusion, patients with HBsAg seroclearance had favorable biochemical, virological, and histological parameters. Intrahepatic HBV DNA level was low and predominantly in the form of cccDNA. However, HCC could still develop, particularly in patients with cirrhosis who had HBsAg seroclearance at an older age. (HEPATOLOGY 2004;39:1694–1701.)


Gut | 2003

A large population study of spontaneous HBeAg seroconversion and acute exacerbation of chronic hepatitis B infection: implications for antiviral therapy

Man-Fung Yuen; He-Jun Yuan; C.-K. Hui; D. K.-H. Wong; W.-M. Wong; Annie O.O. Chan; Benjamin Chun-Yu Wong; Ching-Lung Lai

Background and aim: Clinical data on spontaneous hepatitis B e antigen (HBeAg) seroconversion and acute exacerbation of chronic hepatitis B (CHB) virus infection from large population studies are lacking. In the present study we examined the clinical features and significance of HBeAg seroconversion and acute exacerbation in 3063 Chinese CHB patients. Methods: Clinical assessment, liver biochemistry, hepatitis B virus (HBV) serology and HBV DNA, time of HBeAg seroconversion, and acute exacerbation were monitored. Results: Median age at HBeAg seroconversion was 34.5 years. The cumulative HBeAg seroconversion rate significantly increased with alanine aminotransferase (ALT) levels on presentation (p<0.0001). For patients with ALT levels more than twice the upper limit of normal (ULN) on presentation, the HBeAg seroconversion rate at the fifth year of follow up was 72.4%. After HBeAg seroconversion, 65.2% (73/110) of patients had undetectable HBV DNA levels by the Digene Hybrid Capture assay. Of these, 78.1% still had HBV DNA levels detectable by the Amplicor HBV Monitor Test. We found that 37.5% antibody to HBeAg (anti-HBe) positive patients had undetectable HBV DNA levels by the Digene Hybrid Capture assay before acute exacerbation. Acute exacerbations of longer duration, with higher peak ALT, bilirubin, and α fetoprotein levels were associated with an increased HBeAg seroconversion rate (p<0.0001–0.045). Acute exacerbation with peak ALT levels more than five times the ULN carried a 46.4% chance of HBeAg seroconversion within three months. HBeAg seroreversion and mortality occurred in 2.7% and 0.7% of acute exacerbations, respectively. Conclusion: In the present study we have provided information on HBeAg seroconversion and acute exacerbation, which are important in decision making for CHB treatment and in designing clinical trials.


Hepatology | 2004

Quantitation of covalently closed circular hepatitis B virus DNA in chronic hepatitis B patients

Danny Ka-Ho Wong; Man-Fung Yuen; He-Jun Yuan; Simon Siu-Man Sum; Chee-Kin Hui; Jeff Hall; Ching-Lung Lai

This study examined a signal amplification assay, the Invader assay, for the quantitation of hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) in liver biopsies and sera. DNA was extracted from liver biopsy and serum samples were collected from 16 hepatitis B e antigen (HBeAg)‐positive and 36 antibody‐to‐HBeAg‐positive (anti–HBe‐positive) chronic hepatitis B patients. The amount of total HBV DNA and cccDNA was measured using the Invader assay. Anti–HBe‐positive patients had lower median total intrahepatic HBV DNA (P < .001) and intrahepatic cccDNA levels (P = .001) than HBeAg‐positive patients. Intrahepatic cccDNA correlated positively with the total intrahepatic HBV DNA (r = 0.950, P < .001). However, the proportion of intrahepatic HBV DNA in the form of cccDNA was inversely related to the amount of total intrahepatic HBV DNA (r = −0.822, P < .001). A small amount of cccDNA was detected in 39 of 52 (75%) serum samples. Anti‐HBe‐positive patients had lower median serum cccDNA levels than HBeAg‐positive patients (P = .002). Serum HBV DNA correlated positively with intrahepatic total HBV DNA (r = 0.778, P < .001) and intrahepatic cccDNA (r = 0.481, P = .002). In conclusion, the Invader assay is a reliable assay for the quantitation of cccDNA. Serum and intrahepatic total HBV DNA and cccDNA levels become lower as the disease progresses from HBeAg‐positive to anti–HBe‐positive phase, with cccDNA becoming the predominant form of intrahepatic HBV DNA. (HEPATOLOGY 2004;40:727–737.)


Journal of Viral Hepatitis | 2005

The relationship between HBV‐DNA levels and cirrhosis‐related complications in Chinese with chronic hepatitis B

He-Jun Yuan; M.-F. Yuen; D. Ka-Ho Wong; Erwin Sablon; Ching-Lung Lai

Summary.  We studied the hepatitis B virus (HBV)‐DNA levels below which the development of cirrhosis‐related complications became unlikely in chronic hepatitis B (CHB). Seventy‐nine Chinese CHB patients with cirrhosis‐related complications and 158 age‐, sex‐ and HBeAg status‐matched patients without complications were enrolled. The precore and core promoter mutations were detected by the Line Probe assay (LiPA). HBVDNA levels were determined by Digene assay and Cobas Amplicor Monitor test. Patients with complications had higher HBVDNA levels than those without complications (P = 0.02). HBeAg‐positive patients with complications had similar alanine transferase (ALT) and HBVDNA levels and frequency of precore mutations, but higher frequency of core promoter mutations (P = 0.003), compared with those without complications. Anti‐HBe‐positive patients with complications had higher ALT and HBVDNA levels (P < 0.01) but similar frequency of precore and core promoter mutations, compared with those without complications. Anti‐HBe patients (24.5%) with complications had HBVDNA levels <104 copies/mL. The major factor for the development of cirrhotic complications was viral loads but cirrhotic complications continued to develop in patients with HBVDNA levels below 104 copies/mL.


The Journal of Infectious Diseases | 2002

Relationship between the Development of Precore and Core Promoter Mutations and Hepatitis B e Antigen Seroconversion in Patients with Chronic Hepatitis B Virus

Man-Fung Yuen; Erwin Sablon; He-Jun Yuan; Chee-Kin Hui; Danny Ka-Ho Wong; Joke Doutreloigne; Benjamin Chun-Yu Wong; Annie On-On Chan; Ching-Lung Lai

Chinese patients with chronic hepatitis B virus (332 with and 44 without cirrhosis-related complications) were studied. Fifty percent of patients <30 years old had precore mutations. The prevalence of precore mutations among hepatitis B e antigen (HBeAg)-positive patients, although lower than that among anti-HBe-positive patients (P=.031), was already high (44.2%). Median HBV DNA level in anti-HBe-positive patients was 1.5 x 10(6)-1.55 x 10(6) copies/mL, irrespective of the presence or absence of precore mutations. There was no difference in the prevalence of precore mutations between patients with and without complications (P, not significant). However the prevalence of core promoter mutations was higher among patients with complications than among those without complications (90.5% vs. 69.3%, respectively; P=.003). In conclusion, precore mutations occurred in a large proportion of Chinese patients with chronic hepatitis B virus before HBeAg seroconversion. The development of complications was not related to precore mutations but was probably due to the persistence of significant viremia after HBeAg seroconversion.


Journal of Hepatology | 2003

Clinical outcome and virologic profiles of severe hepatitis B exacerbation due to YMDD mutations

Man-Fung Yuen; Takanobu Kato; Masashi Mizokami; Annie On-On Chan; John Chi-Hang Yuen; He-Jun Yuan; Danny Ka-Ho Wong; Siu-Man Sum; Irene Oi-Lin Ng; Sheung Tat Fan; Ching-Lung Lai

BACKGROUND/AIMS To study the outcome and the virologic profiles of severe hepatitis exacerbations due to YMDD mutants in lamivudine-treated patients. METHODS Eighteen lamivudine-treated patients with severe hepatitis exacerbations due to YMDD mutants were recruited. Laboratory and clinical parameters were monitored. Viral genotypes and YMDD mutations were determined. RESULTS None of the 18 patients had YMDD wild-type during exacerbations. Three (17%) and 15 (83%) patients had genotypes B and C, respectively. Elevated bilirubin levels and prolonged prothrombin time were found in 11 (61%) and six patients (33%) respectively. Three patients (17%) had adverse outcome with the development of ascites and/or encephalopathy. One of these patients required liver transplantation and one died. Both patients had evidence of cirrhosis before treatment and hepatitis B e antigen (HBeAg) seroreversion from anti-HBe positivity. The remaining 16 patients (89%) have no evidence of pre-existing cirrhosis. Thirty seven percent of patients had normal alanine aminotransferase levels at the last follow-up. The median HBV DNA level at the last follow-up was significantly lower than the pre-treatment level (P=0.009). CONCLUSIONS Though the majority of patients with severe hepatitis exacerbations due to YMDD mutants had uneventful course, early liver transplantation should be considered in patients with pre-existing cirrhosis and HBeAg seroreversion.


The American Journal of Gastroenterology | 2003

Transarterial chemoembolization for inoperable, early stage hepatocellular carcinoma in patients with Child-Pugh grade A and B: results of a comparative study in 96 Chinese patients

Man-Fung Yuen; Annie On-On Chan; Benjamin Chun-Yu Wong; Chee-Kin Hui; G.C. Ooi; Wai-Kuen Tso; He-Jun Yuan; Danny Ka-Ho Wong; Ching-Lung Lai

Transarterial chemoembolization for inoperable, early stage hepatocellular carcinoma in patients with Child-Pugh grade A and B: Results of a comparative study in 96 Chinese patients


The American Journal of Gastroenterology | 2004

Significance of HBV DNA levels in liver histology of HBeAg and anti-HBE positive patients with chronic hepatitis B

Man-Fung Yuen; Irene Oi-Lin Ng; Sheung Tat Fan; He-Jun Yuan; Danny Ka-Ho Wong; John Chi-Hang Yuen; Simon Siu-Man Sum; Annie On-On Chan; Ching-Lung Lai

OBJECTIVE:To determine the relationship between hepatitis B virus (HBV) DNA levels and total histologic activity index (HAI), necroinflammation (HAI-NI), and fibrosis (HAI-F) scores.PATIENTS AND METHODS:Liver histology and HBV DNA levels were determined in 94 patients with chronic hepatitis B.RESULTS:There was no association between HBV DNA levels and liver histology in hepatitis-B-e antigen-positive patients (n = 43). In anti-HBe-positive patients (n = 51), HBV DNA levels correlated positively with HAI-NI (r = 0.31, P = 0.014) and HAI-F (r = 0.33, P = 0.017) scores. Though the majority of anti-HBe-positive patients with HBV DNA levels <105 copies/ml had mild necroinflammation and no fibrosis, 14.3% had established fibrosis. Anti-HBe-positive patients with core promoter mutations had a poorer histology compared to those without. There was no difference in the histology between anti-HBe-positive patients with and without precore mutations. Alanine aminotransferase (ALT) level correlated positively with HAI-NI score. Patients with persistently normal ALT levels had a significantly lower median HAI-NI score compared to patients with either persistently or intermittently elevated ALT levels.CONCLUSIONS:In anti-HBe-positive patients, though HBV DNA level <105 copies/ml was associated with better histology, 14.3% patients had established fibrosis. Further studies to define a better cut-off HBV DNA level to differentiate low- and high-risk patients for disease progression are required.


Journal of Clinical Microbiology | 2004

Real-Time PCR Assay Using Molecular Beacon for Quantitation of Hepatitis B Virus DNA

Simon Siu-Man Sum; Danny Ka-Ho Wong; Man-Fung Yuen; He-Jun Yuan; Jian Yu; Ching-Lung Lai; David D. Ho; Linqi Zhang

ABSTRACT Levels of hepatitis B virus (HBV) DNA in the blood serve as an important marker in monitoring the disease progression and treatment efficacy of chronic HBV infection. Several commercial assays are available for accurate measurement of HBV genomic DNA, but many of them are hampered by relatively low sensitivity and limited dynamic range. The aim of this study was to develop a sensitive and accurate assay for measuring HBV genomic DNA using real-time PCR with a molecular beacon (HBV beacon assay). The performance of this assay was validated by testing serial dilutions of the two EUROHEP HBV DNA standards (ad and ay subtypes) of known concentrations. The assay showed low intra-assay (<7%) and interassay (<5%) variations for both subtypes. Its dynamic range was found to be 101 to 107 copies per reaction (1.0 × 102 to 1.0 × 109 copies ml−1). The assay was further evaluated clinically using serum samples from 175 individuals with chronic hepatitis B. The HBV DNA level measured by this assay showed good correlation with that measured by the commercially available COBAS AMPLICOR HBV Monitor test (r = 0.901; P < 0.001). The higher sensitivity and broader dynamic range of this assay compared to the existing commercial assays will provide an ideal tool for monitoring disease progression and treatment efficacy in HBV-infected patients, in particular for those with low levels of HBV viremia.

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Siu-Man Sum

University of Hong Kong

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Chee-Kin Hui

University of Hong Kong

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