22 research outputs found

    Copyright & Privacy - Through the Political Lens, 4 J. Marshall Rev. Intell. Prop. L. 306 (2005)

    Get PDF
    Veteran beltway players discuss the politics of P2P technology and Privacy. How far can or should Congress go? Can the United States export its values or its laws in this area? Are content owners in a losing Luddite struggle? What is the role of litigators, lobbyists and legislators in this war

    Biomarkers of vitamin B-12 status in NHANES: a roundtable summary123456

    Get PDF
    A roundtable to discuss the measurement of vitamin B-12 (cobalamin) status biomarkers in NHANES took place in July 2010. NHANES stopped measuring vitamin B-12–related biomarkers after 2006. The roundtable reviewed 3 biomarkers of vitamin B-12 status used in past NHANES—serum vitamin B-12, methylmalonic acid (MMA), and total homocysteine (tHcy)—and discussed the potential utility of measuring holotranscobalamin (holoTC) for future NHANES. The roundtable focused on public health considerations and the quality of the measurement procedures and reference methods and materials that past NHANES used or that are available for future NHANES. Roundtable members supported reinstating vitamin B-12 status measures in NHANES. They noted evolving concerns and uncertainties regarding whether subclinical (mild, asymptomatic) vitamin B-12 deficiency is a public health concern. They identified the need for evidence from clinical trials to address causal relations between subclinical vitamin B-12 deficiency and adverse health outcomes as well as appropriate cutoffs for interpreting vitamin B-12–related biomarkers. They agreed that problems with sensitivity and specificity of individual biomarkers underscore the need for including at least one biomarker of circulating vitamin B-12 (serum vitamin B-12 or holoTC) and one functional biomarker (MMA or tHcy) in NHANES. The inclusion of both serum vitamin B-12 and plasma MMA, which have been associated with cognitive dysfunction and anemia in NHANES and in other population-based studies, was preferable to provide continuity with past NHANES. Reliable measurement procedures are available, and National Institute of Standards and Technology reference materials are available or in development for serum vitamin B-12 and MMA

    Biomarkers of folate status in NHANES: a roundtable summary123456

    Get PDF
    A roundtable to discuss the measurement of folate status biomarkers in NHANES took place in July 2010. NHANES has measured serum folate since 1974 and red blood cell (RBC) folate since 1978 with the use of several different measurement procedures. Data on serum 5-methyltetrahydrofolate (5MTHF) and folic acid (FA) concentrations in persons aged ≥60 y are available in NHANES 1999–2002. The roundtable reviewed data that showed that folate concentrations from the Bio-Rad Quantaphase II procedure (Bio-Rad Laboratories, Hercules, CA; used in NHANES 1991–1994 and NHANES 1999–2006) were, on average, 29% lower for serum and 45% lower for RBC than were those from the microbiological assay (MA), which was used in NHANES 2007–2010. Roundtable experts agreed that these differences required a data adjustment for time-trend analyses. The roundtable reviewed the possible use of an isotope-dilution liquid chromatography–tandem mass spectrometry (LC-MS/MS) measurement procedure for future NHANES and agreed that the close agreement between the MA and LC-MS/MS results for serum folate supported conversion to the LC-MS/MS procedure. However, for RBC folate, the MA gave 25% higher concentrations than did the LC-MS/MS procedure. The roundtable agreed that the use of the LC-MS/MS procedure to measure RBC folate is premature at this time. The roundtable reviewed the reference materials available or under development at the National Institute of Standards and Technology and recognized the challenges related to, and the scientific need for, these materials. They noted the need for a commutability study for the available reference materials for serum 5MTHF and FA

    Natural killer cells are polarized toward cytotoxicity in chronic hepatitis C in an interferon-alfa-dependent manner

    No full text
    Background & Aims: Patients with chronic hepatitis C virus (HCV) infection display great variability in disease activity and progression. Although virus-specific adaptive immune responses have been characterized extensively and found to be impaired in chronic hepatitis C, the role of innate immune responses in disease activity and progression of chronic hepatitis C is not well understood. Methods: We studied 42 HCV-infected patients and 12 healthy uninfected controls. Results: We found an increased frequency of natural killer (NK) cells expressing tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), NKp44, NKG2C, and CD122 in chronic hepatitis C as compared with healthy controls (P < .05 for all markers) and stronger activation of NK cells in the liver than in the blood (P < .05). This NK cell phenotype was associated with polarization of NK cell function toward CD107a expression as a marker of degranulation, but with not increased interferon (IFN)-γ production of CD56dim NK cells. The polarized NK cell phenotype correlated with alanine aminotransferase levels (r2 = 0.312, P = .03). To investigate whether in vivo exposure of NK cells to HCV-induced type I IFN was causing this NK cell phenotype, peripheral blood mononuclear cells from 10 healthy controls and 8 HCV-infected patients were stimulated in the presence of IFN-alfa, which resulted in increased NK cell expression of TRAIL and CD107a (P < .001), but not IFN-γ. Conclusions: Collectively, these results describe a polarized NK cell phenotype induced by chronic exposure to HCV-induced IFN-alfa. This phenotype may contribute to liver injury through TRAIL expression and cytotoxicity, whereas the lacking increase in IFN-γ production may facilitate the inability to clear HCV

    S-adenosyl methionine improves early viral responses and interferon-stimulated gene induction in hepatitis C nonresponders

    No full text
    Background & Aims: Less than half of patients infected with hepatitis C virus (HCV) achieve sustained viral clearance after pegylated interferon (peginterferon) and ribavirin therapy. S-adenosyl methionine (SAMe) improves interferon signaling in cell culture. We assessed the effect of SAMe on the kinetics of the early antiviral response and interferon signaling in nonresponders to previous antiviral therapy and investigated the mechanisms involved. Methods: Nonresponders with HCV genotype 1 were given peginterferon alfa-2a and ribavirin for 2 weeks (course A, baseline/control). After 1 month, patients received SAMe (1600 mg daily) for 2 weeks and then peginterferon and ribavirin for 48 weeks (course B; completed by 21 of 24 patients). Viral kinetics and interferon-stimulated gene (ISG) expression in peripheral blood mononuclear cells (PBMCs) were compared between courses. Results: The decrease in HCV RNA from 0 to 48 hours (phase 1) was similar with and without SAMe. However, the second phase slope of viral decline was improved with SAMe (course A, 0.11 ± 0.04 log IU/mL/wk; course B, 0.27 ± 0.06; P = .009); 11 patients (53%) achieved an early virological response, and 10 (48%) had undetectable HCV RNA by week 24. Induction of ISGs in PBMCs was significantly greater during course B. In cultured cells, SAMe increased induction of ISGs and the antiviral effects of interferon by increasing STAT1 methylation, possibly affecting STAT1-DNA binding. Conclusions: The addition of SAMe to peginterferon and ribavirin improves the early viral kinetics and increases ISG induction in nonresponders to previous therapy. SAMe might be a useful adjunct to peginterferon-based therapies in chronic HCV infection

    HLA‐B*35:01 and Green Tea–Induced Liver Injury

    No full text
    BACKGROUND: Herbal supplements and particularly multi-ingredient products have become increasingly common causes of acute liver injury. Green tea is a frequent component in implicated products, but its role in liver injury is controversial. METHODS: Among 1414 patients enrolled in the U.S. Drug Induced Liver Injury Network who underwent formal causality assessment, 40 cases (3%) were attributed to green tea, 202 to dietary supplements without green tea, and 1142 to conventional drugs. The clinical features of green tea cases and representation of HLA class I and II alleles in cases and controls were analyzed in detail. RESULTS: Patients with green tea-associated liver injury ranged in age from 17 to 69 years (median = 40) and developed symptoms 15 to 448 days (median = 72) after starting the implicated agent. The liver injury was typically hepatocellular (95%) with marked serum aminotransferase elevations and only modest increases in alkaline phosphatase. Most patients were jaundiced (83%) and symptomatic (88%). The course was judged as severe in 14 patients (35%), necessitating liver transplantation in 3 (8%), but rarely resulting in chronic injury (3%). In three instances, injury recurred upon re-exposure to green tea with similar clinical features but shorter time to onset. HLA typing revealed a high prevalence of HLA-B*35:01, found in 72% (95% CI: 58% to 87%) of green tea cases but only 15% (95% CI: 10% to 20%) caused by other supplements and 12% (95% CI: 10% to 14%) attributed to drugs, the latter rate being similar to population controls (95% CI: 11%: 10.5% to 11.5%). CONCLUSIONS: Green tea-related liver injury has distinctive clinical features and close association with HLA-B*35:01 suggesting that it is idiosyncratic and immune-mediated

    HLA- B*35:01 and Green Tea- Induced Liver Injury

    Get PDF
    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/168251/1/hep31538-sup-0001-Supinfo.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/168251/2/hep31538_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/168251/3/hep31538.pd
    corecore