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1.
researchsquare; 2022.
Preprint in English | PREPRINT-RESEARCHSQUARE | ID: ppzbmed-10.21203.rs.3.rs-1940265.v1

ABSTRACT

Recently, wearing facemasks in public has been raised due to the coronavirus disease 2019 epidemic worldwide. However, the performance and effectiveness of many existing products have raised significant concerns among people and professionals. In this respect, doping or impregnating facemask fabrics with metallic substances or nanoparticles like silver nanoparticles has been proposed. Therefore, in the present study, we aimed to sonochemically deposit silver nanoparticles on the non-woven Spunbond substrates at different sonication times and concentrations to develop reusable antibacterial and antiviral facemask for protection against coronavirus. The coated substrates were characterized in terms of morphological, mechanical, and functional characteristics. The results confirmed high and uniform deposition of silver nanoparticles on Spunbond fabrics with desirable stability and mechanical properties. Evaluation of functional characteristics of the resultant fabrics showed suitable particle filtration efficiency, pressure drop, and electrical conductivity, which are essential elements for a desired facemask with enhanced protection and support of normal breath. The prepared fabrics also showed high antibacterial activity against E. coli and S. aureus bacteria without any significant cytotoxicity effect toward HEK 293 cells and brine shrimp.


Subject(s)
COVID-19
2.
researchsquare; 2021.
Preprint in English | PREPRINT-RESEARCHSQUARE | ID: ppzbmed-10.21203.rs.3.rs-709499.v1

ABSTRACT

The Sputnik V COVID-19 vaccine, have shown excellent safety and efficacy against COVID-19 in phase 3 of the clinical trial. We provided independent evidence on side effects and immunogenicity following the administration of the Sputnik V COVID-19 in Iran. In this observational study, the healthcare workers who vaccinated with the Sputnik V COVID-19 vaccine within February and April 2021 were evaluated. Among a total of 13435 vaccinated healthcare workers, we received 3236 self-declaration reports of Sputnik V associated adverse events with the mean age 39.32±10.19 years old which 38.8% were men and 61.2% were women. The most common side effect was a pain in the injection site (56.9%), fatigue (50.9%), body pain (43.9%), headache (35.7%), fever (32.9%), joint pain (30.3%), chilling (29.8%) and drowsiness (20.3%). Side effects of the vaccine were significantly more frequent in females and younger individuals. Among a total of 238 participants, more than 90% after the first and second dose of vaccine had a detectable level of SARS-CoV-2 RBD antibody and SARS-CoV-2 neutralizing antibody. Although the overall the rate of adverse effects was higher than the interim results from randomized controlled trials, our findings support the manufacturer’s reports about the high humoral immunogenicity of vaccine against COVID-19.


Subject(s)
COVID-19
3.
ssrn; 2021.
Preprint in English | PREPRINT-SSRN | ID: ppzbmed-10.2139.ssrn.3647115

ABSTRACT

Background: As the COVID-19 pandemic unfolded, rapid case increase was observed in multiple cities in Iran. However, in the absence of seroprevalence surveys, the true infection rate remains unknown. In this population-based study we assessed the seroprevalence of SARS-CoV-2 antibodies in eighteen cities of Iran.Methods: We randomly selected and invited study participants from the general population (N = 3,547) and occupations with high risk of COVID-19 exposure, defined as high-risk population (e.g., supermarket employees) (N = 5,391), in eighteen cities of Iran. SARS-CoV-2 ELISA kits were used to detect antibody against COVID-19. Crude, population weight adjusted, and test performance adjusted seroprevalence rates were estimated.Findings: The population weight adjusted and test performance adjusted prevalence rates of antibody seropositivity in general population were 13·1% (95% CI 11·6-14·8%) and 18·5% (95% CI 16·1-21·3%), respectively. The population-weighted seroprevalence estimate implies that 3,290,633 (95% CI 2,907185-3,709,167) individuals, from the eighteen included cities in this study, were infected by end of April 2020.The overall prevalence rate was higher among individuals aged ≥ 60 years (32·0%, 95% CI 23·9-40·8%) and with comorbidity condition (23·7%, 95% CI 18·5-28·8%). The estimated seroprevalence of SARS-CoV-2 antibodies varied greatly by city and the highest population test-adjusted prevalence rates were in Rasht 78·1% (95% CI 58·3-98·3%) and Qom (66·5%, 95% CI 39·9-95·4%) cities. The test-adjusted prevalence did not differ between low and high-risk populations and was about 20.0%.Interpretations: The findings of this study imply that prevalence of seropositivity is likely much higher than the reported prevalence rates based on confirmed COVID-19 cases in Iran. Despite the high seroprevalence rates in a few cities, the low overall prevalence estimates indicate that a large proportion of population is still susceptible to the virus. The similar seroprevalence estimates between low and high-risk occupations might be an indicator of inadequate or low adherence to infection control measures among general population.Funding Statement: Iranian Ministry of Health and Medical Education COVID-19 Grant (number 99-1-97-47964).Declaration of Interests: None to disclose.Ethics Approval Statement: Ethics approval for this study was granted by Vice-Chancellor in Research Affairs-Tehran University of Medical Sciences (IR. TUMS.VCR.REC.1399.308)


Subject(s)
COVID-19
4.
researchsquare; 2020.
Preprint in English | PREPRINT-RESEARCHSQUARE | ID: ppzbmed-10.21203.rs.3.rs-21833.v1

ABSTRACT

The Outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections in late 2019 in China and many other countries around the world necessitate immediate action to develop new drugs against the virus. Repurposing of existing drugs for new targets is a fast, safe and unexpansive approach for this goal. Studies have shown that naproxen could specifically interact with the RNA binding domain of nueclporteins of RNA viruses such as the influenza virus. Therefore, this study aimed to evaluate the binding properties of naproxen to the nucleocapsid protein of SARS-CoV-2. 3D structure of N and C terminal domains of SARS-CoV- 2 nucleocapsid were constructed and each were docked with naproxen and analyzed during 100 ns of molecular dynamics. The results showed that naproxen interacts with the N terminal domain of the nucleocapsid via two salt bridges with Arg 88 and 92 and a network of h-bonds. Molecular dynamics analysis was also revealed that all the coordinations of naproxen with N terminal domain were kept during 100 ns of simulation time. The results of this study provide insights how naproxen can specifically interact with the conserved RNA binding module of the nucleocapsid of SARS-CoV-2 that would inhibit the packaging of viral genome into capsid and virus assembly. Therefore we recommend evaluating the antiviral effects of naproxen against SARS-CoV-2 in in vitro studies and clinical trials.


Subject(s)
Coronavirus Infections
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