Critical analysis: use of polymerase chain reaction to diagnose leprosy

ABSTRACT Leprosy is a neglected tropical disease and an important public health problem, especially in developing countries. It is a chronic infectious disease that is caused by Mycobacterium leprae, which has a predilection for the skin and peripheral nerves. Although it has low sensitivity, slit-skin smear (SSS) remains the conventional auxiliary laboratory technique for the clinical diagnosis of leprosy. Polymerase chain reaction (PCR) is a molecular biology technique that holds promise as a simple and sensitive diagnostic tool. In the present study, the performance of two PCR methods, using different targets, PCR-LP and PCR-P, were compared with SSS with regard to leprosy diagnosis in a reference laboratory. M. leprae DNA was extracted from 106 lymph samples of 40 patients who had clinical suspicion of leprosy. The samples were subjected to both PCR techniques and SSS. Amplification of the human b-globin gene was used as PCR inhibitor control. The specificity of both PCR techniques was 100%, and sensitivity was 0.007 and 0.015 µg/ml for PCR-LP and PCR-P, respectively. No significant difference was found between either the PCR-LP or PCR-P results and SSS results (p > 0.05). Although PCR is not yet a replacement for SSS in the diagnosis of leprosy, this technique may be used as an efficient auxiliary tool for early detection of the disease, especially in endemic regions. This strategy may also be useful in cases in which SSS results are negative (e.g., in paucibacillary patients) and cases in which skin biopsy cannot be performed

Influence of menstrual cycle phase on the efficacy of carbohydrate ingestion during prolonged exercise in trained females

grantor: University of Toronto'Purpose'. To establish the effects of menstrual cycle phase on the efficacy of CHO ingestion during prolonged exercise in trained females. 'Methods'. Six female triathletes completed four exercise trials in a double blind randomized crossover design study. Two trials were completed in each of the follicular (F) and luteal (L) phases, one under each supplement condition; 6% CHO (C) and placebo (P). Subjects exercised on a cycle ergometer at a workrate of ~72.5% V¤O2peak for 1-hr, at which point the workrate was increased to ~82.5% V¤O2peak and the subject exercised to fatigue (FT). Drink supplements were given at rest (5 ml kgBW-1) and every 15-min (3 ml kgBW -1) for the first hour of exercise. Heart rate (HR), rating of perceived exertion (RPE), respiratory exchange ratio (RER), body core temperature (Tre), glucose (GLUC), lactate (LA), insulin (INS), C-peptide (CP), glycerol (GLY), and free fatty acids (FFA) were measured every 15-min and at FT. 'Results'. There was a significant (p <= .05) phase effect in GLY and Tre, drink effect in GLUC and CP, and phase x drink effect in GLY and LA. There were no significant differences in RER, HR, RPE or FT across experimental conditions. 'Conclusions'. These data suggest that there is no phase effect on the efficacy of carbohydrate ingestion during prolonged exercise in trained females. In addition, these findings contrast what has been observed in male athletes, as there was no increase in performance, as measured by fatigue time, amongst the four conditions.M.Sc

A multi-parametric approach to remove the influence of plasma volume on the athlete biological passport during a Union Cycliste Internationale cycling stage race

Fluctuations in plasma volume (PV) present potential confounders within the concentration-based markers of the haematological athlete biological passport (ABP). Here, a multi-parametric approach involving a simple blood test is applied to the current ABP adaptive model in an attempt to remove the influence of PV expansion, induced by a cycling stage race. Blood samples were obtained from 29 professional cyclists (14 male, 15 female) before, during and after 4–5 consecutive days of racing. Whole blood was analysed in accordance with the World Anti-Doping Agency ABP guidelines for haemoglobin ([Hb]) concentration and platelets. Serum and plasma were analysed for transferrin, albumin, calcium, creatinine, total protein and low-density lipoprotein. PV variation (Z-scores) was estimated using a multi-parametric model (consisting of the biomarkers mentioned earlier) and compared against calculated variations in PV (measured via CO-rebreathing). Significant reductions in [Hb] and the OFF-score were observed in female cyclists after 3 and 4 days of racing, with accompanying increases in PV, which returned to baseline values 4 days post competition. Similarly, a significant increase in PV was observed in male cyclists after 3 and 5 days of racing. When individual estimations of PV variance were applied to the adaptive model, the upper and lower reference predictions for [Hb] and the OFF-score were refined such that all outliers consistent with racing-induced PV changes were removed. The PV model appears capable of reducing the influence of PV on concentration-dependent markers during competition. This is an important step towards the inclusion of the PV correction in the ABP haematological module

A multi‐parametric approach to remove the influence of plasma volume on the athlete biological passport during a Union Cycliste Internationale cycling stage race

Fluctuations in plasma volume (PV) present potential confounders within the concentration-based markers of the haematological athlete biological passport (ABP). Here, a multi-parametric approach involving a simple blood test is applied to the current ABP adaptive model in an attempt to remove the influence of PV expansion, induced by a cycling stage race. Blood samples were obtained from 29 professional cyclists (14 male, 15 female) before, during and after 4–5 consecutive days of racing. Whole blood was analysed in accordance with the World Anti-Doping Agency ABP guidelines for haemoglobin ([Hb]) concentration and platelets. Serum and plasma were analysed for transferrin, albumin, calcium, creatinine, total protein and low-density lipoprotein. PV variation (Z-scores) was estimated using a multi-parametric model (consisting of the biomarkers mentioned earlier) and compared against calculated variations in PV (measured via CO-rebreathing). Significant reductions in [Hb] and the OFF-score were observed in female cyclists after 3 and 4 days of racing, with accompanying increases in PV, which returned to baseline values 4 days post competition. Similarly, a significant increase in PV was observed in male cyclists after 3 and 5 days of racing. When individual estimations of PV variance were applied to the adaptive model, the upper and lower reference predictions for [Hb] and the OFF-score were refined such that all outliers consistent with racing-induced PV changes were removed. The PV model appears capable of reducing the influence of PV on concentration-dependent markers during competition. This is an important step towards the inclusion of the PV correction in the ABP haematological module

Longitudinal efficacy and toxicity of SARS-CoV-2 vaccination in cancer patients treated with immunotherapy

Abstract Despite more than 2 years having elapsed since the onset of SARS-CoV-2 pandemic, a level of hesitation around increased SARS-CoV-2 vaccine toxicity in cancer patients receiving immunotherapy (IO) remains. This hesitation stems from the idea that IO agents could elicit an overwhelming immune stimulation post vaccination and therefore increase the risk of vaccine-related toxicity. The aim of our study was to explore serological responses to SARS-CoV-2 vaccination in patients treated with IO and describe the level of immune stimulation using parameters such as blood cytokines, autoantibody levels and immune related adverse events (irAEs) post vaccination. Fifty-one evaluable patients were enrolled in this longitudinal study. Absolute levels and neutralization potential of anti-SARS-CoV-2 antibodies were not significantly different in the IO group compared to non-IO. Chemotherapy adversely affected seroconversion when compared to IO and/or targeted treatment. Following vaccination, the prevalence of grade ≥2 irAEs in patients treated with IO was not higher than the usual reported IO toxicity. We report, for the first time, that anti-SARS-CoV-2 vaccination, elicited the generation of five autoantibodies. The significantly increased autoantibodies were IgM autoantibodies against beta-2 glycoprotein (p = 0.02), myeloperoxidase (p = 0.03), nucleosome (p = 0.041), SPLUNC2 (p < 0.001) and IgG autoantibody against Myosin Heavy Chain 6 (MYH6) (p < 0.001). Overall, comprehensive analysis of a small cohort showed that co-administration of SARS-CoV-2 vaccine and IO is not associated with increased irAEs. Nevertheless, the detection of autoantibodies post anti-SARS-CoV-2 vaccination warrants further investigation (NCT03702309)