PCR amplification of alleles at locus D17S5: population genetic study in Hong Kong Chinese and detection of allelic loss in patients with hepatocellular carcinoma

Abstract no. 2184published_or_final_versio

Statistical Methodological Issues in Handling of Fatty Acid Data: Percentage or Concentration, Imputation and Indices

Basic aspects in the handling of fatty acid-data have remained largely underexposed. Of these, we aimed to address three statistical methodological issues, by quantitatively exemplifying their imminent confounding impact on analytical outcomes: (1) presenting results as relative percentages or absolute concentrations, (2) handling of missing/non-detectable values, and (3) using structural indices for data-reduction. Therefore, we reanalyzed an example dataset containing erythrocyte fatty acid-concentrations of 137 recurrently depressed patients and 73 controls. First, correlations between data presented as percentages and concentrations varied for different fatty acids, depending on their correlation with the total fatty acid-concentration. Second, multiple imputation of non-detects resulted in differences in significance compared to zero-substitution or omission of non-detects. Third, patients’ chain length-, unsaturation-, and peroxidation-indices were significantly lower compared to controls, which corresponded with patterns interpreted from individual fatty acid tests. In conclusion, results from our example dataset show that statistical methodological choices can have a significant influence on outcomes of fatty acid analysis, which emphasizes the relevance of: (1) hypothesis-based fatty acid-presentation (percentages or concentrations), (2) multiple imputation, preventing bias introduced by non-detects; and (3) the possibility of using (structural) indices, to delineate fatty acid-patterns thereby preventing multiple testing

A comparison of hepatitis B viral markers of patients in different clinical stages of chronic infection

Hepatitis B viral markers may be useful for predicting outcomes such as liver-related deaths or development of hepatocellular carcinoma. We determined the frequency of these markers in different clinical stages of chronic hepatitis B infection. We compared baseline hepatitis B viral markers in 317 patients who were enrolled in a prospective study and identified the frequency of these tests in immune-tolerant (IT) patients, in inactive carriers , and in patients with either hepatitis B e antigen ( HBeAg)- positive or HBeAg-negative chronic hepatitis or cirrhosis. IT patients were youngest (median age 27 years) and HBeAg- negative patients with cirrhosis were oldest (median age 58 years) (p = 0.03 to < 0.0001). The male to female ratio was similar both in IT patients and in inactive carriers, but there was a male preponderance both in patients with chronic hepatitis and in patients with cirrhosis (p < 0.0001). The A1896 precore mutants were most prevalent in inactive carriers (36.4%) and HBeAg- negative patients with chronic hepatitis (38.8%; p < 0.0001), and the T 1762/A1764 basal core promoter mutants were most often detected in HBeAg- negative patients with cirrhosis (65.1%; p = 0.02). Genotype A was detected only in 5.3% of IT patients, and genotype B was least often detected in both HBeAg-Positive patients with chronic hepatitis and cirrhosis (p = 0.03). The hepatitis B viral DNA levels were lowest in inactive carriers (2.69 log(10) IU/mL) and highest in IT patients (6. 80 log(10) IU/mL; p = 0.02 to < 0.0001). At follow-up, HBeAg-positive and HBeAg-negative patients with cirrhosis accounted for 57 of 64 (89.1%) liver-related deaths (p < 0. 0001). Differences in baseline hepatitis B viral markers were detected in patients in various clinical stages of hepatitis B virus infection. HBeAg-positive and HBeAg- negative patients with cirrhosis accounted for the majority of the liver-related fatalities

TGF-β1 Down-Regulation of NKG2D/DAP10 and 2B4/SAP Expression on Human NK Cells Contributes to HBV Persistence

The mechanism underlying persistent hepatitis B virus (HBV) infection remains unclear. We investigated the role of innate immune responses to persistent HBV infection in 154 HBV-infected patients and 95 healthy controls. The expression of NKG2D- and 2B4-activating receptors on NK cells was significantly decreased, and moreover, the expression of DAP10 and SAP, the intracellular adaptor proteins of NKG2D and 2B4 (respectively), were lower, which then impaired NK cell-mediated cytotoxic capacity and interferon-γ production. Higher concentrations of transforming growth factor-beta 1 (TGF-β1) were found in sera from persistently infected HBV patients. TGF-β1 down-regulated the expression of NKG2D and 2B4 on NK cells in our in vitro study, leading to an impairment of their effector functions. Anti-TGF-β1 antibodies could restore the expression of NKG2D and 2B4 on NK cells in vitro. Furthermore, TGF-β1 induced cell-cycle arrest in NK cells by up-regulating the expression of p15 and p21 in NK cells from immunotolerant (IT) patients. We conclude that TGF-β1 may reduce the expression of NKG2D/DAP10 and 2B4/SAP, and those IT patients who are deficient in these double-activating signals have impaired NK cell function, which is correlated with persistent HBV infection

Clinical and prognostic analysis of hepatitis B virus infection in diffuse large B-cell lymphoma

<p>Abstract</p> <p>Background</p> <p>Hepatitis B virus (HBV) infection in diffuse large B-cell lymphoma (DLBCL) patients is a common complication in China. However, the clinical relevance of HBV infection with respect to DLBCL disease stages and patient survival remains unclear. The main objective of the current study was to analyze the clinical features and to evaluate the prognostic factors of HBV infection in DLBCL patients.</p> <p>Methods</p> <p>In this retrospective study, DLBCL patients were divided into two groups as HBsAg-positive (n = 81) and HBsAg-negative (n = 181) patients. The HBsAg-positive patients were further divided into two subgroups based on their hepatic function during chemotherapy. Various statistical analyses were used to determine the significance of the relevant clinical parameters.</p> <p>Results</p> <p>Compared with the HBsAg-negative group, the HBsAg-positive DLBCL group displayed a younger median onset age (46 year vs 51), more advanced stage at grade III/IV (58% vs 42%, p = 0.016), and more frequent hepatic dysfunction before (21% vs 5.5%, p < 0.001) and during (49.4% vs 16.6%, p < 0.001) chemotherapy. Female DLBCL patients exhibited a higher frequency of HBsAg positivity (p = 0.006). However, in both groups the median overall survival (OS) duration (55.8 vs 66.8 months) and response rates (91% vs 90.4%) were similar. In the HBsAg-positive DLBCL group, the poor prognostic factors were advanced stage (p < 0.001) and hepatic dysfunction during chemotherapy (p = 0.02). The OS of HBsAg-positive patients with hepatic dysfunction during chemotherapy was significantly shorter than those without liver dysfunction (p = 0.016), and the OS rates at 3 years were 48% and 72%, respectively. The use of rituximab did not increase the rates of liver dysfunction in HBsAg-positive DLBCL patients.</p> <p>Conclusion</p> <p>Compared with HBsAg-negative patients, the HBsAg-positive DLBCL patients had earlier onset and more advanced stage. The disease stage and hepatic dysfunction during chemotherapy and were two significant prognostic factors in the HBsAg-positive DLBCL patients. This study suggests that prophylactic treatment of HBV may be of great importance in the cases of HBsAg-positive patients.</p

Measurement of the Bottom-Strange Meson Mixing Phase in the Full CDF Data Set

We report a measurement of the bottom-strange meson mixing phase \beta_s using the time evolution of B0_s -> J/\psi (->\mu+\mu-) \phi (-> K+ K-) decays in which the quark-flavor content of the bottom-strange meson is identified at production. This measurement uses the full data set of proton-antiproton collisions at sqrt(s)= 1.96 TeV collected by the Collider Detector experiment at the Fermilab Tevatron, corresponding to 9.6 fb-1 of integrated luminosity. We report confidence regions in the two-dimensional space of \beta_s and the B0_s decay-width difference \Delta\Gamma_s, and measure \beta_s in [-\pi/2, -1.51] U [-0.06, 0.30] U [1.26, \pi/2] at the 68% confidence level, in agreement with the standard model expectation. Assuming the standard model value of \beta_s, we also determine \Delta\Gamma_s = 0.068 +- 0.026 (stat) +- 0.009 (syst) ps-1 and the mean B0_s lifetime, \tau_s = 1.528 +- 0.019 (stat) +- 0.009 (syst) ps, which are consistent and competitive with determinations by other experiments.Comment: 8 pages, 2 figures, Phys. Rev. Lett 109, 171802 (2012

Asian-Pacific consensus statement on the management of chronic hepatitis B: a 2008 update

Large amounts of new data on the natural history and treatment of chronic hepatitis B virus (HBV) infection have become available since 2005. These include long-term follow-up studies in large community-based cohorts or asymptomatic subjects with chronic HBV infection, further studies on the role of HBV genotype/naturally occurring HBV mutations, treatment of drug resistance and new therapies. In addition, Pegylated interferon α2a, entecavir and telbivudine have been approved globally. To update HBV management guidelines, relevant new data were reviewed and assessed by experts from the region, and the significance of the reported findings were discussed and debated. The earlier “Asian-Pacific consensus statement on the management of chronic hepatitis B” was revised accordingly. The key terms used in the statement were also defined. The new guidelines include general management, special indications for liver biopsy in patients with persistently normal alanine aminotransferase, time to start or stop drug therapy, choice of drug to initiate therapy, when and how to monitor the patients during and after stopping drug therapy. Recommendations on the therapy of patients in special circumstances, including women in childbearing age, patients with antiviral drug resistance, concurrent viral infection, hepatic decompensation, patients receiving immune-suppressive medications or chemotherapy and patients in the setting of liver transplantation, are also included

Transient Ureteral Obstruction Prevents against Kidney Ischemia/Reperfusion Injury via Hypoxia-Inducible Factor (HIF)-2α Activation

Although the protective effect of transient ureteral obstruction (UO) prior to ischemia on subsequent renal ischemia/reperfusion (I/R) injury has been documented, the underlying molecular mechanism remains to be understood. We showed in the current study that 24 h of UO led to renal tubular hypoxia in the ipsilateral kidney in mice, with the accumulation of hypoxia-inducible factor (HIF)-2α, which lasted for a week after the release of UO. To address the functions of HIF-2α in UO-mediated protection of renal IRI, we utilized the Mx-Cre/loxP recombination system to knock out target genes. Inactivation of HIF-2α, but not HIF-1α blunted the renal protective effects of UO, as demonstrated by much higher serum creatinine level and severer histological damage. UO failed to prevent postischemic neutrophil infiltration and apoptosis induction in HIF-2α knockout mice, which also diminished the postobstructive up-regulation of the protective molecule, heat shock protein (HSP)-27. The renal protective effects of UO were associated with the improvement of the postischemic recovery of intra-renal microvascular blood flow, which was also dependent on the activation of HIF-2α. Our results demonstrated that UO protected the kidney via activation of HIF-2α, which reduced tubular damages via preservation of adequate renal microvascular perfusion after ischemia. Thus, preconditional HIF-2α activation might serve as a novel therapeutic strategy for the treatment of ischemic acute renal failure