Relationship of influenza vaccine match and use rate to medically attended acute respiratory illnesses in older residents of Maryland. November 13, 2012

The effectiveness of seasonal influenza vaccine may be influenced by mismatches to circulating influenza viruses. The relationship of these vaccine mismatches to the occurrence of medically attended acute respiratory illnesses (MAARI)-related emergency department (ED) visits and hospitalizations for all Maryland residents aged 50 years or older was examined for seven years (2001–2008). Also, relationships of individual circulating influenza types or subtypes to these MAARI-encounters were investigated.     

Evaluation of aggressively treated patients with unresectable multiple liver metastases from colorectal cancer

PURPOSE: The aim of this study was to assess the value of aggressively treating patients with unresectable liver metastases from colorectal cancer and a poor prognosis. METHODS: From 1988 to 1999, 64 patients with unresectable multiple liver metastases from colorectal cancer who had received hepatic arterial infusion chemotherapy were investigated. All patients did not have synchronous extrahepatic metastases at the time of initiating our treatment. When liver metastases were suitable for resection after hepatic arterial infusion chemotherapy, we excised them and repeated prophylactic hepatic arterial infusion chemotherapy as long as possible. We evaluated the efficacy of hepatic arterial infusion chemotherapy by computed tomography and divided these patients into responders and nonresponders. We performed univariate analysis using the log-rank test to calculate predictive factors. In addition, the Cox proportional hazards model was used to perform multivariate analysis of factors related to survival. RESULTS: The survival rate of all patients was 67.8 percent after 1 year and 10 percent after 5 years. However, the survival rate for 16 patients who received hepatectomy after hepatic arterial infusion chemotherapy was 35.1 percent after five years. Multivariate analysis demonstrated that the response after hepatic arterial infusion chemotherapy was the most indicative prognostic factor. CONCLUSIONS: The prognosis of selected patients who responded to hepatic arterial infusion chemotherapy and received hepatectomy was improved. Applying aggressive treatment as outlined in our strategy may improve the chances of long-term survival.     

Peginterferon Alfa-2a and ribavirin in patients with chronic hepatitis C who have failed prior treatment

The most effective therapy currently available for treatment of chronic hepatitis C virus (HCV) is the combination of peginterferon and ribavirin. This study evaluated the effectiveness of this treatment in patients who were nonresponders to previous interferon-based therapy. The first 604 patients enrolled in the Hepatitis C Antiviral Long-Term Treatment Against Cirrhosis (HALT-C) Trial were evaluated. All were HCV RNA positive, previous nonresponders to interferon, with or without ribavirin, and had bridging fibrosis or cirrhosis on liver biopsy (Ishak fibrosis stage 3-6). Patients were retreated with peginterferon alfa-2a 180 μg/wk plus ribavirin 1000-1200 mg/day. Those with no detectable HCV RNA in serum at week 20 continued treatment for a total of 48 weeks and were then followed for an additional 24 weeks. Thirty-five percent of patients had no detectable HCV RNA in serum at treatment week 20, and 18% achieved sustained virologic response (SVR). Factors associated with an SVR included previous treatment with interferon monotherapy, infection with genotypes 2 or 3, a lower AST:ALT ratio, and absence of cirrhosis. Reducing the dose of ribavirin from ≥80% to ≤60% of the starting dose during the first 20 weeks of treatment was associated with a decline in SVR from 21% to 11% (P ≤ 0.05). In contrast, reducing the dose of peginterferon or reducing ribavirin after week 20, when HCV RNA was already undetectable, did not significantly affect SVR. Selected nonresponders to previous interferon-based therapy can achieve SVR following retreatment with peginterferon alfa-2a and ribavirin.     

A novel serological assay for influenza based on DiD fluorescence dequenching that is free from observer bias and potentially automatable – A proof of concept study

BackgroundSerum hemagglutination inhibition (HAI) and microneutralization (MN) antibodies are often used as a correlate of protection for influenza. However, these manual assays are labor-intensive and difficult to standardize due to variability in biologic reagents used and subjective interpretation of the results.MethodsSera with known HAI and MN titers were used to assess a novel test based on the inhibition of fluorescence ‘dequenching’. Whole influenza virions (A/California/07/2009 (H1N1), A/Hong Kong/4801/2014 (H3N2) and B/Brisbane/60/2008) labelled with 1,1′-dioctadecyl-3,3,3′,3′-tetramethylindodicarbocyanine perchlorate (DiD) were exposed to serial dilutions of serum and mixed with turkey red blood cells followed by acidification of the media (pH 5.0–5.5). The H1N1 and B/Brisbane strains were high hemagglutinating while the H3N2 strain had low hemagglutinating activity. In some experiments, labelled virions were subjected to repetitive freeze-thaw cycles prior to use in the assay.ResultsIn the absence of detectable HAI/MN antibodies, there were consistent and substantial increases from baseline DiD fluorescence upon acidification. Sera with known high titer HAI/MN antibodies reduced or completely prevented DiD dequenching at low dilutions with progressive increases in fluorescence at higher dilutions, which permitted a reproducible assignment of an antibody ‘titer’ based on baseline and acidified DiD fluorescence values. The ‘titers’ measured by the DiD dequenching assay were highly correlated with HAI/MN results for the H1N1 and B strains (Spearman’s correlation coefficients (r_s) 0.874 to 0.946, p < 10⁻⁷ to 10⁻³⁵). Correlations with HAI/MN titres for the low-hemagglutinating H3N2 strain tested were lower but remained statistically significant (r_s 0.547–0.551, p < 0.004). Freeze-thawing of the DiD pre-stained virus stocks had no significant impact on the results of the assay.ConclusionsThe DiD dequenching assay may be a labour-saving and more objective alternative to the classic serologies. This novel assay could theoretically be standardized across laboratories using pre-stained virions and has the potential to be fully automated.     

Assay of blood and tissue aldehydes by HPLC analysis of their 2,4-dinitrophenylhydrazine adducts

A new method for the assay of blood and tissue acetaldehyde is described. Samples are reacted with a methanolic solution of 2,4-dinitrophenylhydrazine (DNP) and the DNP-aldehyde adducts extracted into CHCl₃. DNP-[¹⁴C]formaldehyde is added as internal standard. The CHCl₃ extracts are washed with HC1 and H₂O and purified by aluminium oxide chromatography. The eluate is dried down, re-dissolved in methanol and subjected to quantitative analysis by HPLC. The acetaldehyde adduct was identified by co-chromatography with the authentic derivative and by mass spectrometry. Recoveries of added acetaldehyde were 85% and addition of 20 mmol ethanol to the sample gave no apparent increment in acetaldehyde content. This technique is suitable for assessment of acetaldehyde levels in clinical and experimental studies of ethanol metabolism.     

Comparison of monoclonal and polyclonal antibodies in a two-site binding enzyme immunoassay for alphafetoprotein (AFP)

A two-site binding enzyme immunoassay for the detection of alphafetoprotein (AFP) was developed by using either a combination of two monoclonal antibodies or of one monoclonal antibody and polyclonal antibodies. The conjugation of the monoclonal antibodies to peroxidase by the periodate method yielded a somewhat higher sensitivity in the enzyme immunoassay (EIA), when compared to conjugates produced by the glutaraldehyde method. The detection limit was 10 micrograms AFP per litre when using only monoclonal antibodies in the assay. Simultaneous incubation of the sample and the monoclonal labelled antibody should be avoided unless using at least two different dilutions of the sample for investigation.     

Ehanced expression of interleukin-6 in chronic hepatitis C

Abstract: Aims/Background: There is a possibility that proinflammatory cytokines such as interleukin-6 (IL-6) are involved in the inflammatory process of chronic hepatitis C. This study was undertaken to investigate the possible role of IL-6 in the pathophysiology of chronic hepatitis C. Methods: Serum IL-6 levels in 63 patients with chronic hepatitis C and in 26 normal controls were measured. Light and electron immunostaining studies to localize IL-6 protein as well as in situ hybridization to localize IL-6 messenger RNA were performed on 10 liver biopsy specimens. Results: Serum IL-6 levels were significantly (p<0.01) elevated in chronic hepatitis C compared to those in normal controls. Although no statistically significant correlation was found between serum IL-6 levels and hepatobiliary enzyme levels, a significant correlation (p<0.01) was found between serum IL-6 levels and category II of Knodell's histological activity index score. Non-parenchymal cells in hepatic sinusoids and the cells infiltrating enlarged fibrous portal tracts were definitely positive for IL-6 protein and mRNA by immunohistochemistry and in situ hybridization. In addition, immunoelectron microscopy revealed a weak and occasional positive reaction in the cytoplasm of hepatocytes. The majority of the positive cells in hepatic sinusoids showed CD68 immunoreactivity in consecutive sections indicating that these were Kupffer cells. Sinusoidal endothelial cells and hepatic stellate cells also exhibited a weak reaction. Conclusion: These results strongly suggest that Kupffer cells in liver parenchyma and macrophages infiltrating in portal tracts are the main producers of elevated IL-6 in serum. Moreover, there is a possibility that IL-6 produced by hepatocytes could also act as a regenerative stimulus to hepatocytes themselves in an autocrine fashion.