25 research outputs found
Hepatitis B assays in serum, plasma and whole blood on filter paper
BACKGROUND: Screening and determining the immune status of individuals for hepatitis B is usually done by detecting hepatitis B surface antigen (HBsAg) and hepatitis B surface antigen-specific antibodies (HBsAb). In some countries with the highest viral burden, performing these assays is currently impractical. This paper explores the use of filter paper as a blood specimen transport medium. METHODS: Samples, chosen from routine clinical laboratory pool, were applied and dried onto filter paper. Eluates, from the paper samples, were analyzed as routine clinical specimens on ADVIA Centaur 5634® immunoassay analyzers using the standard HBsAg and HBsAb kits. Dried blood samples were subjected to a range of environmental conditions in order to assess stability. RESULTS: After drying and elution the assays showed linearity and precision comparable to clinical assays performed on fresh serum. Elutions at various times during a 149 day incubation period showed very little variability in the Index numbers. All analytes were temperature stable except for a decrease in the HBsAg signal at 42°C. CONCLUSIONS: Filter paper is an acceptable storage and transport medium for serum to be used in the detection of hepatitis B markers if atmospheric variability can be controlled. HBsAg, HBsAb and HBcAb are all stable for at least five months under storage conditions below room temperature. Drying specimens, particularly serum, on filter paper at remote locations, offers a reasonable solution to the problem of hepatitis surveillance in underdeveloped regions, although some attempt at temperature control might be desirable
Recommended from our members
Health care system planning for and response to a nuclear detonation
The hallmark of a successful response to a nuclear detonation will be the resilience of the community, region, and nation. An incident of this magnitude will rapidly become a national incident; however, the initial critical steps to reduce lives lost, save the lives that can be saved with the resources available, and understand and apply resources available to a complex and dynamic situation will be the responsibility of the local and regional responders and planners. Expectations of the public health and health care systems will be met to the extent possible by coordination, cooperation, and an effort to produce as consistent a response as possible for the victims. Responders will face extraordinarily stressful situations, and their own physical and psychological health is of great importance to optimizing the response. This article illustrates through vignettes and supporting text how the incident may unfold for the various components of the health and medical systems and provides additional context for the discipline-related actions outlined in the state and local planners’ playbook
Colorectal cancer incidences in Lynch syndrome: a comparison of results from the prospective lynch syndrome database and the international mismatch repair consortium
Objective To compare colorectal cancer (CRC) incidences in carriers of pathogenic variants of the MMR genes in the PLSD and IMRC cohorts, of which only the former included mandatory colonoscopy surveillance for all participants. Methods CRC incidences were calculated in an intervention group comprising a cohort of confirmed carriers of pathogenic or likely pathogenic variants in mismatch repair genes (path_MMR) followed prospectively by the Prospective Lynch Syndrome Database (PLSD). All had colonoscopy surveillance, with polypectomy when polyps were identified. Comparison was made with a retrospective cohort reported by the International Mismatch Repair Consortium (IMRC). This comprised confirmed and inferred path_MMR carriers who were first- or second-degree relatives of Lynch syndrome probands. Results In the PLSD, 8,153 subjects had follow-up colonoscopy surveillance for a total of 67,604 years and 578 carriers had CRC diagnosed. Average cumulative incidences of CRC in path_MLH1 carriers at 70 years of age were 52% in males and 41% in females; for path_MSH2 50% and 39%; for path_MSH6 13% and 17% and for path_PMS2 11% and 8%. In contrast, in the IMRC cohort, corresponding cumulative incidences were 40% and 27%; 34% and 23%; 16% and 8% and 7% and 6%. Comparing just the European carriers in the two series gave similar findings. Numbers in the PLSD series did not allow comparisons of carriers from other continents separately. Cumulative incidences at 25 years were < 1% in all retrospective groups. Conclusions Prospectively observed CRC incidences (PLSD) in path_MLH1 and path_MSH2 carriers undergoing colonoscopy surveillance and polypectomy were higher than in the retrospective (IMRC) series, and were not reduced in path_MSH6 carriers. These findings were the opposite to those expected. CRC point incidence before 50 years of age was reduced in path_PMS2 carriers subjected to colonoscopy, but not significantly so
Effect of aliskiren on post-discharge outcomes among diabetic and non-diabetic patients hospitalized for heart failure: insights from the ASTRONAUT trial
Aims The objective of the Aliskiren Trial on Acute Heart Failure Outcomes (ASTRONAUT) was to determine whether aliskiren, a direct renin inhibitor, would improve post-discharge outcomes in patients with hospitalization for heart failure (HHF) with reduced ejection fraction. Pre-specified subgroup analyses suggested potential heterogeneity in post-discharge outcomes with aliskiren in patients with and without baseline diabetes mellitus (DM). Methods and results ASTRONAUT included 953 patients without DM (aliskiren 489; placebo 464) and 662 patients with DM (aliskiren 319; placebo 343) (as reported by study investigators). Study endpoints included the first occurrence of cardiovascular death or HHF within 6 and 12 months, all-cause death within 6 and 12 months, and change from baseline in N-terminal pro-B-type natriuretic peptide (NT-proBNP) at 1, 6, and 12 months. Data regarding risk of hyperkalaemia, renal impairment, and hypotension, and changes in additional serum biomarkers were collected. The effect of aliskiren on cardiovascular death or HHF within 6 months (primary endpoint) did not significantly differ by baseline DM status (P = 0.08 for interaction), but reached statistical significance at 12 months (non-DM: HR: 0.80, 95% CI: 0.64-0.99; DM: HR: 1.16, 95% CI: 0.91-1.47; P = 0.03 for interaction). Risk of 12-month all-cause death with aliskiren significantly differed by the presence of baseline DM (non-DM: HR: 0.69, 95% CI: 0.50-0.94; DM: HR: 1.64, 95% CI: 1.15-2.33; P < 0.01 for interaction). Among non-diabetics, aliskiren significantly reduced NT-proBNP through 6 months and plasma troponin I and aldosterone through 12 months, as compared to placebo. Among diabetic patients, aliskiren reduced plasma troponin I and aldosterone relative to placebo through 1 month only. There was a trend towards differing risk of post-baseline potassium ≥6 mmol/L with aliskiren by underlying DM status (non-DM: HR: 1.17, 95% CI: 0.71-1.93; DM: HR: 2.39, 95% CI: 1.30-4.42; P = 0.07 for interaction). Conclusion This pre-specified subgroup analysis from the ASTRONAUT trial generates the hypothesis that the addition of aliskiren to standard HHF therapy in non-diabetic patients is generally well-tolerated and improves post-discharge outcomes and biomarker profiles. In contrast, diabetic patients receiving aliskiren appear to have worse post-discharge outcomes. Future prospective investigations are needed to confirm potential benefits of renin inhibition in a large cohort of HHF patients without D
Recommended from our members