Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 7 de 7
Filter
1.
ScientificWorldJournal ; 2021: 9342748, 2021.
Article in English | MEDLINE | ID: covidwho-1495720

ABSTRACT

BACKGROUND: Recently, an outbreak of a novel human coronavirus SARS-CoV-2 has become a world health concern leading to severe respiratory tract infections in humans. Virus transmission occurs through person-to-person contact, respiratory droplets, and contaminated hands or surfaces. Accordingly, we aim at reviewing the literature on all information available about the persistence of coronaviruses, including human and animal coronaviruses, on inanimate surfaces and inactivation strategies with biocides employed for chemical and physical disinfection. METHOD: A comprehensive search was systematically conducted in main databases from 1998 to 2020 to identify various viral disinfectants associated with HCoV and methods for control and prevention of this newly emerged virus. RESULTS: The analysis of 62 studies shows that human coronaviruses such as severe acute respiratory syndrome (SARS) coronavirus, Middle East respiratory syndrome (MERS) coronavirus or endemic human coronaviruses (HCoV), canine coronavirus (CCV), transmissible gastroenteritis virus (TGEV), and mouse hepatitis virus (MHV) can be efficiently inactivated by physical and chemical disinfectants at different concentrations (70, 80, 85, and 95%) of 2-propanol (70 and 80%) in less than or equal to 60 s and 0.5% hydrogen peroxide or 0.1% sodium hypochlorite within 1 minute. Additionally, glutaraldehyde (0.5-2%), formaldehyde (0.7-1%), and povidone-iodine (0.1-0.75%) could readily inactivate coronaviruses. Moreover, dry heat at 56°C, ultraviolet light dose of 0.2 to 140 J/cm2, and gamma irradiation could effectively inactivate coronavirus. The WHO recommends the use of 0.1% sodium hypochlorite solution or an ethanol-based disinfectant with an ethanol concentration between 62% and 71%. CONCLUSION: The results of the present study can help researchers, policymakers, health decision makers, and people perceive and take the correct measures to control and prevent further transmission of COVID-19. Prevention and decontamination will be the main ways to stop the ongoing outbreak of COVID-19.


Subject(s)
COVID-19/prevention & control , Disinfectants/pharmacology , Disinfection/instrumentation , SARS-CoV-2 , Virus Inactivation/drug effects , 2-Propanol/pharmacology , Animals , COVID-19/virology , Coronavirus, Canine/drug effects , Disinfection/methods , Ethanol/pharmacology , Formaldehyde/pharmacology , Gamma Rays , Glutaral/pharmacology , Hot Temperature , Humans , Hydrogen Peroxide/pharmacology , Mice , Middle East Respiratory Syndrome Coronavirus/drug effects , Murine hepatitis virus/drug effects , Povidone-Iodine/pharmacology , SARS Virus/drug effects , Sodium Hypochlorite/pharmacology , Transmissible gastroenteritis virus/drug effects , Ultraviolet Rays
2.
Sci Rep ; 11(1): 19888, 2021 10 06.
Article in English | MEDLINE | ID: covidwho-1454817

ABSTRACT

To cope with the shortage of filtering facepiece respirators (FFRs) during the coronavirus (COVID-19) pandemic, healthcare institutions were forced to reuse FFRs after applying different decontamination methods including gamma-irradiation (GIR). The aim of this study was to evaluate the effect of GIR on the filtration efficiency (FE) of FFRs and on SARS-CoV-2 detection. The FE of 2 FFRs types (KN95 and N95-3 M masks) was assessed at different particle sizes (0.3-5 µm) following GIR (0-15 kGy) delivered at either typical (1.65 kGy/h) or low (0.5088 kGy/h) dose rates. The detection of two SARS-CoV-2 RNA genes (E and RdRp4) following GIR (0-50 kGy) was carried out using RT-qPCR assay. Both masks showed an overall significant (P < 0.001) reduction in FE with increased GIR doses. No significant differences were observed between GIR dose rates on FE. The GIR exhibited significant increases (P ≤ 0.001) in the cycle threshold values (ΔCt) of both genes, with no detection following high doses. In conclusion, complete degradation of SARS-CoV-2 RNA can be achieved by high GIR (≥ 30 kGy), suggesting its potential use in FFRs decontamination. However, GIR exhibited adverse effects on FE in dose- and particle size-dependent manners, rendering its use to decontaminate FFRs debatable.


Subject(s)
COVID-19/virology , Decontamination/methods , Masks , SARS-CoV-2/isolation & purification , Ventilators, Mechanical , COVID-19/prevention & control , COVID-19/transmission , Filtration , Gamma Rays , Humans , Particle Size
3.
Sci Rep ; 11(1): 15799, 2021 08 04.
Article in English | MEDLINE | ID: covidwho-1343474

ABSTRACT

The SARS-CoV-2 virus caused the most severe pandemic around the world, and vaccine development for urgent use became a crucial issue. Inactivated virus formulated vaccines such as Hepatitis A and smallpox proved to be reliable approaches for immunization for prolonged periods. In this study, a gamma-irradiated inactivated virus vaccine does not require an extra purification process, unlike the chemically inactivated vaccines. Hence, the novelty of our vaccine candidate (OZG-38.61.3) is that it is a non-adjuvant added, gamma-irradiated, and intradermally applied inactive viral vaccine. Efficiency and safety dose (either 1013 or 1014 viral RNA copy per dose) of OZG-38.61.3 was initially determined in BALB/c mice. This was followed by testing the immunogenicity and protective efficacy of the vaccine. Human ACE2-encoding transgenic mice were immunized and then infected with the SARS-CoV-2 virus for the challenge test. This study shows that vaccinated mice have lowered SARS-CoV-2 viral RNA copy numbers both in oropharyngeal specimens and in the histological analysis of the lung tissues along with humoral and cellular immune responses, including the neutralizing antibodies similar to those shown in BALB/c mice without substantial toxicity. Subsequently, plans are being made for the commencement of Phase 1 clinical trial of the OZG-38.61.3 vaccine for the COVID-19 pandemic.


Subject(s)
COVID-19 Vaccines/immunology , COVID-19/prevention & control , SARS-CoV-2/immunology , Angiotensin-Converting Enzyme 2/genetics , Angiotensin-Converting Enzyme 2/metabolism , Animals , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Chlorocebus aethiops , Cytokines/metabolism , Dose-Response Relationship, Immunologic , Gamma Rays , Humans , Immunity , Lung/pathology , Mice , Mice, Inbred BALB C , Mice, Transgenic , RNA, Viral , SARS-CoV-2/radiation effects , Vaccination , Vaccines, Inactivated/immunology , Vero Cells , Virus Replication
4.
PLoS One ; 16(4): e0248859, 2021.
Article in English | MEDLINE | ID: covidwho-1172874

ABSTRACT

In response to personal protective equipment (PPE) shortages in the United States due to the Coronavirus Disease 2019, two models of N95 respirators were evaluated for reuse after gamma radiation sterilization. Gamma sterilization is attractive for PPE reuse because it can sterilize large quantities of material through hermetically sealed packaging, providing safety and logistic benefits. The Gamma Irradiation Facility at Sandia National Laboratories was used to irradiate N95 filtering facepiece respirators to a sterilization dose of 25 kGy(tissue). Aerosol particle filtration performance testing and electrostatic field measurements were used to determine the efficacy of the respirators after irradiation. Both respirator models exhibited statistically significant decreases in particle filtering efficiencies and electrostatic potential after irradiation. The largest decrease in capture efficiency was 40-50% and peaked near the 200 nm particle size. The key contribution of this effort is correlating the electrostatic potential change of individual filtration layer of the respirator with the decrease filtration efficiency after irradiation. This observation occurred in both variations of N95 respirator that we tested. Electrostatic potential measurement of the filtration layer is a key indicator for predicting filtration efficiency loss.


Subject(s)
COVID-19/prevention & control , Gamma Rays , N95 Respirators/virology , SARS-CoV-2 , Sterilization , Virus Inactivation/radiation effects , COVID-19/transmission , Humans , United States
5.
Sci Rep ; 11(1): 5804, 2021 03 11.
Article in English | MEDLINE | ID: covidwho-1132095

ABSTRACT

COVID-19 outbreak caused by SARS-CoV-2 created an unprecedented health crisis since there is no vaccine for this novel virus. Therefore, SARS-CoV-2 vaccines have become crucial for reducing morbidity and mortality. In this study, in vitro and in vivo safety and efficacy analyzes of lyophilized vaccine candidates inactivated by gamma-irradiation were performed. The candidate vaccines in this study were OZG-3861 version 1 (V1), an inactivated SARS-CoV-2 virus vaccine, and SK-01 version 1 (V1), a GM-CSF adjuvant added vaccine. The candidate vaccines were applied intradermally to BALB/c mice to assess toxicity and immunogenicity. Preliminary results in vaccinated mice are reported in this study. Especially, the vaccine models containing GM-CSF caused significant antibody production with neutralization capacity in absence of the antibody-dependent enhancement feature, when considered in terms of T and B cell responses. Another important finding was that the presence of adjuvant was more important in T cell in comparison with B cell response. Vaccinated mice showed T cell response upon restimulation with whole inactivated SARS-CoV-2 or peptide pool. This study shows that the vaccines are effective and leads us to start the challenge test to investigate the gamma-irradiated inactivated vaccine candidates for infective SARS-CoV-2 virus in humanized ACE2 + mice.


Subject(s)
COVID-19 Vaccines/immunology , Immunogenicity, Vaccine , Vaccines, Inactivated/immunology , Animals , COVID-19 Vaccines/toxicity , Female , Gamma Rays , Genome, Viral , Humans , Male , Mice, Inbred BALB C , SARS-CoV-2/genetics , Vaccines, Inactivated/toxicity
6.
Anal Chem ; 93(5): 2950-2958, 2021 02 09.
Article in English | MEDLINE | ID: covidwho-1041144

ABSTRACT

There is an urgent need for ultrarapid testing regimens to detect the severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2] infections in real-time within seconds to stop its spread. Current testing approaches for this RNA virus focus primarily on diagnosis by RT-qPCR, which is time-consuming, costly, often inaccurate, and impractical for general population rollout due to the need for laboratory processing. The latency until the test result arrives with the patient has led to further virus spread. Furthermore, latest antigen rapid tests still require 15-30 min processing time and are challenging to handle. Despite increased polymerase chain reaction (PCR)-test and antigen-test efforts, the pandemic continues to evolve worldwide. Herein, we developed a superfast, reagent-free, and nondestructive approach of attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy with subsequent chemometric analysis toward the prescreening of virus-infected samples. Contrived saliva samples spiked with inactivated γ-irradiated COVID-19 virus particles at levels down to 1582 copies/mL generated infrared (IR) spectra with a good signal-to-noise ratio. Predominant virus spectral peaks are tentatively associated with nucleic acid bands, including RNA. At low copy numbers, the presence of a virus particle was found to be capable of modifying the IR spectral signature of saliva, again with discriminating wavenumbers primarily associated with RNA. Discrimination was also achievable following ATR-FTIR spectral analysis of swabs immersed in saliva variously spiked with virus. Next, we nested our test system in a clinical setting wherein participants were recruited to provide demographic details, symptoms, parallel RT-qPCR testing, and the acquisition of pharyngeal swabs for ATR-FTIR spectral analysis. Initial categorization of swab samples into negative versus positive COVID-19 infection was based on symptoms and PCR results (n = 111 negatives and 70 positives). Following training and validation (using n = 61 negatives and 20 positives) of a genetic algorithm-linear discriminant analysis (GA-LDA) algorithm, a blind sensitivity of 95% and specificity of 89% was achieved. This prompt approach generates results within 2 min and is applicable in areas with increased people traffic that require sudden test results such as airports, events, or gate controls.


Subject(s)
Algorithms , COVID-19/diagnosis , SARS-CoV-2/physiology , Spectroscopy, Fourier Transform Infrared/methods , Virion/chemistry , COVID-19/virology , Discriminant Analysis , Gamma Rays , Humans , Point-of-Care Testing , Principal Component Analysis , SARS-CoV-2/isolation & purification , Saliva/virology , Sensitivity and Specificity , Signal-To-Noise Ratio , Virion/radiation effects , Virus Inactivation
7.
Cells ; 9(9)2020 09 02.
Article in English | MEDLINE | ID: covidwho-742752

ABSTRACT

We have previously shown that the combination of radiotherapy with human umbilical-cord-derived mesenchymal stromal/stem cells (MSCs) cell therapy significantly reduces the size of the xenotumors in mice, both in the directly irradiated tumor and in the distant nonirradiated tumor or its metastasis. We have also shown that exosomes secreted from MSCs preirradiated with 2 Gy are quantitatively, functionally and qualitatively different from the exosomes secreted from nonirradiated mesenchymal cells, and also that proteins, exosomes and microvesicles secreted by MSCs suffer a significant change when the cells are activated or nonactivated, with the amount of protein present in the exosomes of the preirradiated cells being 1.5 times greater compared to those from nonirradiated cells. This finding correlates with a dramatic increase in the antitumor activity of the radiotherapy when is combined with MSCs or with preirradiated mesenchymal stromal/stem cells (MSCs*). After the proteomic analysis of the load of the exosomes released from both irradiated and nonirradiated cells, we conclude that annexin A1 is the most important and significant difference between the exosomes released by the cells in either status. Knowing the role of annexin A1 in the control of hypoxia and inflammation that is characteristic of acute respiratory-distress syndrome (ARDS), we designed a hypothetical therapeutic strategy, based on the transplantation of mesenchymal stromal/stem cells stimulated with radiation, to alleviate the symptoms of patients who, due to pneumonia caused by SARS-CoV-2, require to be admitted to an intensive care unit for patients with life-threatening conditions. With this hypothesis, we seek to improve the patients' respiratory capacity and increase the expectations of their cure.


Subject(s)
Gamma Rays , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells/radiation effects , Respiratory Distress Syndrome/therapy , Annexin A1/metabolism , Betacoronavirus/isolation & purification , COVID-19 , Clinical Trials as Topic , Coronavirus Infections/therapy , Coronavirus Infections/virology , Exosomes/metabolism , Humans , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/metabolism , Pandemics , Pneumonia, Viral/therapy , Pneumonia, Viral/virology , Respiratory Distress Syndrome/pathology , Respiratory Distress Syndrome/virology , SARS-CoV-2
SELECTION OF CITATIONS
SEARCH DETAIL