Altered ratio of IFN-γ/IL-10 in patients with drug resistant Mycobacterium tuberculosis and HIV-tuberculosis immune reconstitution inflammatory syndrome

We have described a clinical relationship between HIV-Tuberculosis Immune Reconstitution Inflammatory Syndrome (TB-IRIS) and anti-tubercular drug resistance. Here we studied the immune response of TB-IRIS patients from whom a drug-resistant (n = 11) or drug-susceptible (n = 25) Mycobacterium tuberculosis (MTB) strain was isolated after presenting with TB-IRIS. ELISpot analysis and multiplex cytokine analysis of the supernatant collected from peripheral blood mononuclear cells stimulated overnight with the heat-killed H37Rv MTB laboratory strain was used. Although there was no statistical difference in IFN-gamma ELISpot responses between the two groups, the results point towards higher bacterial load in the drug-resistant patients, possibly due to failed therapy. The ratio between secreted IFN-gamma/IL-10 and IL-2/IL-10 was significantly lower in TB-IRIS patients in whom the cause of TB was a drug-resistant strain compared to those with a fully sensitive strain (p = 0.02). Since host immune responses are dependent on the bacterial load, we hypothesise that the impaired cytokine balance is likely to be caused by the poorly controlled bacterial growth in these patients

Age-related decline in associative learning in healthy Chinese adults

10.1371/journal.pone.0080648PLoS ONE811-POLN

2015/16 seasonal vaccine effectiveness against hospitalisation with influenza a(H1N1)pdm09 and B among elderly people in Europe: Results from the I-MOVE+ project

We conducted a multicentre test-negative caseâ\u80\u93control study in 27 hospitals of 11 European countries to measure 2015/16 influenza vaccine effectiveness (IVE) against hospitalised influenza A(H1N1)pdm09 and B among people aged â\u89¥ 65 years. Patients swabbed within 7 days after onset of symptoms compatible with severe acute respiratory infection were included. Information on demographics, vaccination and underlying conditions was collected. Using logistic regression, we measured IVE adjusted for potential confounders. We included 355 influenza A(H1N1)pdm09 cases, 110 influenza B cases, and 1,274 controls. Adjusted IVE against influenza A(H1N1)pdm09 was 42% (95% confidence interval (CI): 22 to 57). It was 59% (95% CI: 23 to 78), 48% (95% CI: 5 to 71), 43% (95% CI: 8 to 65) and 39% (95% CI: 7 to 60) in patients with diabetes mellitus, cancer, lung and heart disease, respectively. Adjusted IVE against influenza B was 52% (95% CI: 24 to 70). It was 62% (95% CI: 5 to 85), 60% (95% CI: 18 to 80) and 36% (95% CI: -23 to 67) in patients with diabetes mellitus, lung and heart disease, respectively. 2015/16 IVE estimates against hospitalised influenza in elderly people was moderate against influenza A(H1N1)pdm09 and B, including among those with diabetes mellitus, cancer, lung or heart diseases

Quantum superposition of target and product states in reactive eectron scattering from CF₄ revealed through velocity slice iImaging

Exploiting the technique of velocity slice imaging, we have performed a detailed study of reactive electron scattering with CF4. We have measured the electron impact energy dependence of both the angular and kinetic energy distributions of the channels yielding F− and CF−3 anions. These data provide an unprecedented insight into the quantum superposition of the target state and product channels, respectively, of Td and C3v symmetry, and shed new light on the dissociation dynamics

Dissociative electron attachment to acetaldehyde, CH₃CHO. A laboratory study using the velocity map imaging technique

A detailed experimental investigation of the dissociative electron attachment (DEA) process to acetaldehyde, CH3CHO is presented. To investigate this process we use a time of flight spectrometer coupled with the velocity slice imaging technique. DEA in CH3CHO is found to lead to the formation of CH3−, O−, OH−, C2H−, C2HO− and CH3CO− anionic products produced through scattering resonances in the electron energy range of 6 to 13 eV. Of these product ions only O− is formed with any measurable kinetic energy distribution indicating a two-body dissociation process. CH3CO−, although formed with very low kinetic energy, shows anisotropy in the velocity slice image, indicating ejection of the H atom in the 180° direction with respect to the electron beam. The low kinetic energy distributions and absence of any anisotropy in the angular distributions of the other product ions indicate that they are formed through multiple fragmentation of the transient molecular negative ion. The angular distribution of O− is analysed in terms of the various partial waves

CovidNudge: diagnostic accuracy of a novel lab-free point-of-care diagnostic for SARS-CoV-2

Background Access to rapid diagnosis is key to the control and management of SARS-CoV-2. Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR) testing usually requires a centralised laboratory and significant infrastructure. We describe the development and diagnostic accuracy assessment of a novel, rapid point-of-care RT-PCR test, the DnaNudge® platform CovidNudge test, which requires no laboratory handling or sample pre-processing. Methods Nasopharyngeal swabs are inserted directly into a cartridge which contains all reagents and components required for RT-PCR reactions, including multiple technical replicates of seven SARS-CoV-2 gene targets (rdrp1, rdrp2, e-gene, n-gene, n1, n2 and n3) and human ribonuclease P (RNaseP) as positive control. Between April and May 2020, swab samples were tested in parallel using the CovidNudge direct-to-cartridge platform and standard laboratory RT-PCR using swabs in viral transport medium. Samples were collected from three groups: self-referred healthcare workers with suspected COVID-19 (Group 1, n=280/386; 73%); patients attending the emergency department with suspected COVID-19 (Group 2, n=15/386; 4%) and hospital inpatient admissions with or without suspected COVID-19 (Group 3, n=91/386; 23%). Results Of 386 paired samples tested across all groups, 67 tested positive on the CovidNudge platform and 71 with standard laboratory RT-PCR. The sensitivity of the test varied by group (Group 1 93% [84-98%], Group 2 100% [48-100%] and Group 3 100% [29-100%], giving an average sensitivity of 94.4% (95% confidence interval 86-98%) and an overall specificity of 100% (95%CI 99-100%; Group 1 100% [98-100%]; Group 2 100% [69-100%] and Group 3 100% [96-100%]). Point of care testing performance was comparable during a period of high (25%) and low (3%) background prevalence. Amplification of the viral nucleocapsid (n1, n2, n3) targets were most sensitive for detection of SARS-CoV2, with the assay able to detect 1×104 viral particles in a single swab. Conclusions The CovidNudge platform offers a sensitive, specific and rapid point of care test for the presence of SARS-CoV-2 without laboratory handling or sample pre-processing. The implementation of such a device could be used to enable rapid decisions for clinical care and testing programs. Evidence before this study The WHO has highlighted the development of rapid, point-of-care diagnostics for detection of SARS-CoV-2 as a key priority to tackle COVID-19. The Foundation for Innovative Diagnostics (FIND) has identified over 90 point-of-care, near patient or mobile tests for viral detection of SARS-CoV-2. However, the most widely available rapid tests to date require some sample handling which limits their use at point-of-care. In addition, pressure on supply chains is restricting access to current diagnostics and alternatives are needed urgently. Added value of this study We describe the development and clinical validation of COVID nudge, a novel point-of-care RT-PCR diagnostic, evaluated during the first wave of the SARS-CoV-2 epidemic. The platform is able to achieve high analytic sensitivity and specificity from dry swabs within a self-contained cartridge. The lack of downstream sample handling makes it suitable for use in a range of clinical settings, without need for a laboratory or specialized operator. Multiplexed assays within the cartridge allow inclusion of a positive human control, which reduces the false negative testing rate due to insufficient sampling. Implication of the available evidence Point-of-care testing can relieve pressure on centralized laboratories and increase overall testing capacity, complementing existing approaches. These findings support a role for COVID Nudge as part of strategies to improve access to rapid diagnostics to SARS-CoV-2. Since May 2020, the system has been implemented in UK hospitals and is being rolled out nationwide. Competing Interest Statement CT, RS, MS, CI, MK, TH, SDM, FL, JB and AO are employees of DnaNudge. CT is named on the patent for method and apparatus for analyzing biological specimens on the DnaNudge platform (US Patent No: US 10,093,965 B216. LSPM has consulted for bioMerieux (2013 to 2020), DNAelectronics (2015), Dairy Crest (2017 to 2018), Pfizer (2018-2020), and Umovis Lab (2020), received speaker fees from Profile Pharma (2018), received research grants from the National Institute for Health Research (2013 to 2019), Leo Pharma (2016), and CW+ Charity (2018 to 2019), and received educational support from Eumedica (2016 to 2017). NM has received speaker fees from Beyer (2016) and Pfizer (2019) and received educational support from Eumedica (2016) and Baxter (2017). All other authors have no conflicts of interest to declare. Funding Statement The work was supported by the Biomedical Research Centre of Imperial College NHS Trust. M.M.G. is supported in part by the NIHR Imperial Biomedical Research Centre. GC is an NIHR Research Professor and Investigator within the NIHR London In-vitro Diagnostic Collaborative. Part of this work was supported by the National Institute for Health Research Health Protection Research Unit (NIHR HPRU) in Healthcare Associated Infections and Antimicrobial Resistance at Oxford University in partnership with Public Health England (PHE) [grant HPRU-2012-10041] and the NIHR Biomedical Research Centre, Oxford. The views expressed in this publication are those of the authors and not necessarily those of the NHS, the National Institute for Health Research, the Department of Health or Public Health England

IFN-gamma- and TNF-independent vitamin D-inducible human suppression of mycobacteria: The role of cathelicidin LL-37

Vitamin D deficiency is associated with susceptibility to tuberculosis, and its biologically active metabolite, 1 alpha,25 dihydroxyvitamin D-3 (1 alpha,25(OH)(2)D-3), has pleiotropic immune effects. The mechanisms by which 1 alpha,25(OH)(2)D-3 protects against tuberculosis are incompletely understood. 1 alpha,25(OH)(2)D-3 reduced the growth of mycobacteria in infected human PBMC cultures in a dose-dependent fashion. Coculture with agonists or antagonists of the membrane or nuclear vitamin D receptors indicated that these effects were primarily mediated by the nuclear vitamin D receptors. 1 alpha,25(OH)(2)D-3 reduced transcription and secretion of protective IFN-gamma, IL-12p40, and TNF in infected PBMC and macrophages, indicating that 1 alpha,25(OH)(2)D-3 does not mediate protection via these cytokines. Although NOM was up-regulated by 1 alpha,25(OH)(2)D-3, inhibition of NO formation marginally affected the suppressive effect of 1 alpha,25(OH)(2)D-3 on bacillus Calmette Guerin in infected cells. By contrast, 1 alpha,25(OH)(2)D-3 strongly up-regulated the cathelicidin hCAP-18 gene, and some hCAP-18 polypeptide colocalized with CD14 in 1 alpha,25(OH)(2)D-3 stimulated PBMC, although no detectable LL-37 peptide was found in supernatants from similar 1 alpha,25(OH)(2)D-3-stimulated PBMC cultures. A total of 200 mu g/ml of the active peptide LL-37, in turn, reduced the growth of Mycobacterium tuberculosis in culture by 75.7%. These findings suggest that vitamin D contributes to protection against TB by '' nonclassical '' mechanisms that include the induction of antimicrobial peptides

The ratio of secreted cytokines measured by luminex analysis in the supernatants of peripheral blood mononuclear cells (PBMC) stimulated with heat killed H37Rv (MOI = 1∶1) for 24 hours.

<p><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0046481#s3" target="_blank">Results</a> from TB-IRIS patients with multi-drug resistant (MDR) TB are shown in black full circles (n = 7), rifampicin mono-resistant (RM) cases are shown as a cross (n = 3), and fully sensitive (FS) TB cases are shown as open circles (n = 10).</p