Repurposing existing medications for coronavirus disease 2019: protocol for a rapid and living systematic review.

BACKGROUND: Coronavirus disease 2019 (COVID-19) has no confirmed specific treatments. However, there might be in vitro and early clinical data as well as evidence from severe acute respiratory syndrome and Middle Eastern respiratory syndrome that could inform clinicians and researchers. This systematic review aims to create priorities for future research of drugs repurposed for COVID-19. METHODS: This systematic review will include in vitro, animal, and clinical studies evaluating the efficacy of a list of 34 specific compounds and 4 groups of drugs identified in a previous scoping review. Studies will be identified both from traditional literature databases and pre-print servers. Outcomes assessed will include time to clinical improvement, time to viral clearance, mortality, length of hospital stay, and proportions transferred to the intensive care unit and intubated, respectively. We will use the GRADE methodology to assess the quality of the evidence. DISCUSSION: The challenge posed by COVID-19 requires not just a rapid review of drugs that can be repurposed but also a sustained effort to integrate new evidence into a living systematic review. TRIAL REGISTRATION: PROSPERO 2020 CRD42020175648.

Repurposing Existing Medications for Coronavirus Disease 2019: Protocol for a Rapid and Living Systematic Review.

BACKGROUND: Coronavirus Disease 2019 (COVID-19) has no known specific treatments. However, there might be in vitro and early clinical data as well as evidence from Severe Acute Respiratory Syndrome and Middle Eastern Respiratory Syndrome that could inform clinicians and researchers. This systematic review aims to create priorities for future research of drugs repurposed for COVID-19. METHODS: This systematic review will include in vitro, animal, and clinical studies evaluating the efficacy of a list of 34 specific compounds and four groups of drugs identified in a previous scoping review. Studies will be identified both from traditional literature databases and pre-print servers. Outcomes assessed will include time to clinical improvement, time to viral clearance, mortality, length of hospital stay, and proportions transferred to the intensive care unit and intubated, respectively. We will use the GRADE methodology to assess the quality of the evidence. DISCUSSION: The challenge posed by COVID-19 requires not just a rapid review of drugs that can be repurposed but also a sustained effort to integrate new evidence into a living systematic review. SYSTEMATIC REVIEW REGISTRATION: PROSPERO 2020 CRD42020175648.

Prospective cross-sectional study of tuberculosis screening in United Arab Emirates.

OBJECTIVES: Intense migrations from tuberculosis endemic areas to Gulf countries create special risks for people in the region. The purpose of this study was to provide data that could justify implementing universal, regular TB screening in UAE. DESIGN: This prospective, cross-sectional study used interferon-γ release assay (IGRA) to screen for TB among Emirati citizens between August-2016 and May-2017; expatriates were not included in this study. Participants were recruited from Emiratis attending Tawam Hospital Polyclinics for problems unrelated to TB risk assessment. IGRA was requested for all enrolled participants. A risk-assessment questionnaire was completed by all participants. In addition, a retrospective review of IGRA results (January-2011 to April-2016) was conducted to compare prevalence of positive IGRA in the 'prospective sample' with that in 'patients screened in the past'. RESULTS: Four hundred fifty-five participants (69% females) were enrolled in this study. Participants' age (mean±SD) was 42±16y. The majority of participants had traveled to or had helpers from TB-endemic areas. Two hundred forty (53%) participants had IGRA test. Forty-five (18.8%) participants had positive IGRA, similar to the retrospective results of 12.4% to 23.5%. CONCLUSIONS: The prevalence of positive-IGRA in this study is high.

Crystal structure of A-site deficient La0.2Sr0.7-xCaxTiO3 perovskite at ambient conditions and high temperatures: a neutron powder diffraction study.

The crystal structures of several members of the solid solution perovskite La(0.2)Sr(0.7-x)CaxTiO(3) were investigated using the Rietveld analysis of neutron powder diffraction patterns collected in ambient conditions and high temperatures. At room temperature, samples showed a tetragonal I4/mcm symmetry for compositions with 0.1 ≤x≤ 0.35 followed by a phase transition to the orthorhombic Pbnm symmetry for compositions with 0.4 ≤x≤ 0.7. Samples with the orthorhombic symmetry showed two reversible phase transitions in the temperature range 20 °C-900 °C. The first phase transition was a discontinuous Pbnm-I4/mcm around 300 °C and the second was a continuous I4/mcm-Pm3[combining macron]m transition around 900 °C. The lower symmetries resulted from very small distortions and changes in tilts of the BO(6) octahedra of this perovskite material; which was a direct result from the A-site ionic radius mismatch.