The Production of Standardized Samples with Known Concentrations for Severe Acute Respiratory Syndrome Coronavirus 2 RT-qPCR Testing Validation for Developing Countries in the Period of the Pandemic Era.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a pandemic of pneumonia spreading around the world, leading to serious threats to public health and attracting enormous attention. There is an urgent need for sensitive diagnostic testing implementation to control and manage SARS-CoV-2 in public health laboratories. The quantitative reverse transcription PCR (RT-qPCR) assay is the gold standard method, but the sensitivity and specificity of SARS-CoV-2 testing are dependent on a number of factors. METHODS: We synthesized RNA based on the genes published to estimate the concentration of inactivated virus samples in a biosafety level 3 laboratory. The limit of detection (LOD), linearity, accuracy, and precision were evaluated according to the bioanalytical method validation guidelines. RESULTS: We found that the LOD reached around 3 copies/reaction. Furthermore, intra-assay precision, accuracy, and linearity met the accepted criterion with an RSD for copies of less than 25%, and linear regression met the accepted R 2 of 0.98. CONCLUSIONS: We suggest that synthesized RNA based on the database of the NCBI gene bank for estimating the concentration of inactivated virus samples provides a potential opportunity for reliable testing to diagnose coronavirus disease 2019 (COVID-19) as well as limit the spread of the disease. This method may be relatively quick and inexpensive, and it may be useful for developing countries during the pandemic era. In the long term, it is also applicable for evaluation, verification, validation, and external quality assessment.

Impacts of Antioxidant Vitamins, Curry Consumption and Heavy Metal Levels on The Metabolic Syndrome With Comorbidities: A National Cross-Sectional Study (preprint)

The burden of metabolic syndrome (MetS) is increasing worldwide especially in the coronavirus disease 2019 (COVID-19). This phenomenon can be related to environmental, dietary, and lifestyle risk factors. We aimed to determine the association between the levels of serum heavy metals, vitamins, and curry intake, subsequently predict the risks for MetS by margin effects. Daily intake of vitamins was measured by 24-h recall was calculated using a food frequency questionnaire. Heavy metals were quantified by graphite furnace atomic absorption spectrometry, and mercury analyzer. The risk of MetS was significantly lower in the high curry consumption than in the low curry consumption, risks of Mets were reduced by 7%, 13%, 1%, and 1%, when the levels of vitamin B1, B2, B3, and C intake increased by one mg, respectively. However, risks of Mets were increased by 9%, 3%, 5%, when the levels of serum Pb, Hg, and CRP increased by one unit. The potential health benefits resulting from vitamin and curry supplementation could guard the public against the dual burden of communicable and non-communicable diseases. Further works are required to thwart risk factors related to heavy metals and determine the mechanistic dual effects of vitamins and curry in MetS.

Comparison of Primer-Probe Sets among Different Master Mixes for Laboratory Screening of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2).

BACKGROUND: There is a shortage of chemical reagents for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) diagnosis and a surge of SARS-CoV-2 cases, especially in limited-resource settings. Therefore, the combination of an optimal assay kit is necessary. METHODS: We compared the ability to screen SARS-CoV-2 among three primer-probe sets in two different master mixes, Invitrogen™ SuperScript™ III One-Step RT-PCR and LightCycler Multiplex RNA Virus Master. RESULTS: The assay with TIB-Molbiol, IDT, and Phu Sa sets for LightCycler Multiplex RNA Virus Master or Invitrogen™ SuperScript™ III One-Step RT-PCR showed positive results from a single reaction of triplicate in the three days of 4.8 copies per reaction. R squared and amplification efficiency were 0.97 and ranged from 107 to 108%, respectively. CONCLUSIONS: Our findings indicated that TIB-Molbiol, IDT, and Phu Sa primer-probe sets could be beneficial for the laboratory screening of SARS-CoV-2 by RT-qPCR assay of E gene. There is a need to consider the combination of these reagent sets as a new strategy to increase the testing capacity of screening programs for COVID-19.