Reverse transcription loop-mediated isothermal amplification assays for rapid identification of eastern and western strains of bluetongue virus in India.

Bluetongue virus (BTV) infects all ruminants, including cattle, goats and camelids, causing bluetongue disease (BT) that is often severe in naïve deer and sheep. Reverse-transcription-loop-mediated-isothermal-amplification (RT-LAMP) assays were developed to detect eastern or western topotype of BTV strains circulating in India. Each assay uses four primers recognizing six distinct sequences of BTV genome-segment 1 (Seg-1). The eastern (e)RT-LAMP and western (w)RT-LAMP assay detected BTV RNA in all positive isolates that were tested (n=52, including Indian BTV-1, -2, -3, -5, -9, -10, -16, -21 -23, and -24 strains) with high specificity and efficiency. The analytical sensitivity of the RT-LAMP assays is comparable to real-time RT-PCR, but higher than conventional RT-PCR. The accelerated eRT-LAMP and wRT-LAMP assays generated detectable levels of amplified DNA, down to 0.216 fg of BTV RNA template or 108 fg of BTV RNA template within 60-90min respectively. The assays gave negative results with RNA from foot-and-mouth-disease virus (FMDV), peste des petits ruminants virus (PPRV), or DNA from Capripox viruses and Orf virus (n=10), all of which can cause clinical signs similar to BT. Both RT-LAMP assays did not show any cross-reaction among themselves. The assays are rapid, easy to perform, could be adapted as a 'penside' test making them suitable for 'front-line' diagnosis, helping to identify and contain field outbreaks of BTV.

Impact of Digoxin on Mortality in Patients With Atrial Fibrillation Stratified by Heart Failure: Findings From Gulf Survey of Atrial Fibrillation Events in the Middle East.

OBJECTIVE: The use of digoxin in patients having atrial fibrillation (AF) with or without heart failure (HF) is not without controversy. The aim of this study was to examine the impact of digoxin therapy on mortality stratified by HF. METHODS: Gulf Survey of Atrial Fibrillation Events was a prospective, multinational, observational registry of consecutive patients with AF recruited from the emergency department of 23 hospitals in 6 countries in the Middle East. Patients were recruited between October 2009 and June 2010 and followed up for 1 year after enrollment. Analyses were performed using univariate and multivariate statistical techniques. RESULTS: The study included a total of 1962 patients with AF, with an overall mean age of 56 ± 16 years, and 52% (n = 1026) were males. At hospital discharge, digoxin was prescribed in 36% (n = 709) of the patients, whereas HF was present in 27% (n = 528) of the cohort. A total of 225 (12.1%) patients died during the 12-month follow-up period after discharge (5.3% [n = 104] were lost to follow-up). Patients with HF were consistently associated with higher mortality at 1 month (5.1% vs 2.1%; P < .001), 6 months (17.2% vs 5.0%; P < 0.001), and 12 months (24.3% vs 7.6%; P < .001) when compared to those without HF. When stratified by HF, digoxin therapy was associated with significantly higher mortality in those without HF at 6 months (8.7% vs 3.7%; adjusted odds ratio (aOR), 5.07; P < .001) and 12 months (12.3% vs 6.0%; aOR, 4.22; P < .001) but not in those with HF (6 months: 18.6% vs 14.7%; aOR, 1.62; P = .177 and 12 months: 25.4% vs 22.4%; aOR, 1.37; P = .317). CONCLUSIONS: In patients with AF and HF, digoxin did not offer any survival advantages. However, in those without HF, digoxin therapy was, in fact, associated with significantly higher long-term mortality.