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1.
Atmosphere-Korea ; 32(1):51-60, 2022.
Article in Korean | Web of Science | ID: covidwho-1822624

ABSTRACT

Corona Virus Disease 19 pandemic (COVID-19) causes many deaths worldwide, and has enormous impacts on society and economy. The COVID-19 was caused by a new type of coronavirus (Severe Acute Respiratory Syndrome Cornonavirus 2;SARS-CoV-2), which has been found that these viruses can be effectively inactivated by ultraviolet (UV) radiation of 290315 nm. In this study, 90% inactivation time of the SARS-CoV-2 virus was analyzed using ground observation data from Brewer spectrophotometer at Yonsei University, Seoul and simulation data from UVSPEC for the period of 2015-2017 and 2020. Based on 12:00-13:00 noon time, the shortest virus inactivation time were estimated as 13.5 minutes in June and 4.8 minutes in July/August, respectively, under all sky and clear sky conditions. In the diurnal and seasonal variations, SARS-CoV-2 could be inactivated by 90% when exposed to UV radiation within 60 minutes from 10:00 to 14:00, for the period of spring to autumn. However, in winter season, the natural prevention effect was meaningless because the intensity of UV radiation weakened, and the time required for virus inactivation increased. The spread of infectious diseases such as COVID-19 is related to various and complex interactions of several variables, but the natural inactivation of viruses by UV radiation presented in this study, especially seasonal differences, need to be considered as major variables.

2.
Vaccines ; 10(4), 2022.
Article in English | EMBASE | ID: covidwho-1822451

ABSTRACT

COVID-19 remains a deadly disease that poses a serious threat to humanity. COVID-19 vaccines protect the public and limit viral spread. However, public acceptance is significantly dependent on the efficacy and side effects (SEs) of the vaccinations being produced. Four important mechanisms have been examined for COVID-19 vaccines: DNA-based, mRNA-based, protein-based, and inactivated viruses. Vaccination safety research was formerly limited to manufacturer-sponsored studies, but numerous additional cross-sectional survey-based studies conducted globally have contributed to the generation of vaccine-related safety data reports. Twenty-seven studies and twenty-four case reports published-up till 2021 were overviewed for the presentation of SEs and their severity. Injection site pain remained the most dominant localized SE, while headache and fatigue were the most prevalent systemic SEs. Most studies reported that all vaccinations were safe, with very little or no adverse effects, but the nature of SEs was reported to be more persistent in DNA-and mRNA-based vaccines, while inactivated viral vaccines were associated with longer-duration SEs. Overall, SEs were found to be more dominant in women and youngsters. Case reports of adverse reactions have also been documented, but there is still a need to find out their pathological linkage with the COVID-19 vaccination.

3.
FASEB Journal ; 35(SUPPL 1), 2021.
Article in English | EMBASE | ID: covidwho-1821960

ABSTRACT

Introduction and Objectives Novel SARS-CoV-2 virus has been implicated in prompting a bold immune response that leads to severe Coronavirus disease 2019 (COVID-19). Recent studies have shown that SARSCoV-2-infected monocytes and macrophages are stimulated to produce an overabundance of pro-inflammatory cytokines and chemokines to generate a cytokine storm. Cytokines in excess can contribute to local tissue inflammation and the pathogenesis of COVID-19. However, the mechanism by which SARS-CoV-2 signal macrophage-derived inflammatory response remains unclear. In the present study, we used RAW 264.7 cells, a wellcharacterized macrophage model, to study the in vitro effects of SARS-CoV-2 on reactive oxygen species (ROS) production and its potential role in the signal transduction of cytokine production. Methods The effect of SARS-CoV-2 on ROS and cytokine generation in macrophages was assessed by treating RAW 264.7 cells with SARS-CoV-2 heat inactivated virus (0-20 million viral particles) or recombinant proteins for 24 hours. 2',7'-Dichlorodihydrofluorescein (2',7'-DCF) fluorescence analysis was utilized to quantify ROS generation within the RAW 264.7 macrophage cell line. Cell culture medium was sampled to quantify the levels of tumor necrosis factor (TNF) using enzyme-linked immunosorbent assay (ELISA). To assess the effects of SARS-CoV-2 on mitochondrial function, cells were treated with SARS-CoV-2 heat inactivated virus (0-20 million viral particles) for 24 hrs. Mitochondria-derived superoxide was measured using the MitoSOX™ red mitochondrial superoxide indicator. Results Treatment of RAW 264.7 cells with inactivated SARS-CoV-2 viral particles or recombinant proteins stimulated ROS production. Mitochondria-derived superoxide and hydrogen peroxide production were increased in response to inactivated SARS-CoV-2 viral particles and recombinant protein exposure. The increased ROS generation is linked to macrophage activation induced by SARS-CoV-2 exposures. Along with the ROS generation, increased TNF production was observed. Conclusions The results of this study suggest that both SARS-CoV-2 viral proteins and heat-inactivated viral particle exposures cause significant generation of ROS and cytokines by RAW 264.7 cells. ROS generation and the subsequent cytokine release apparently play a significant role in the pathogenesis associated with the SARS-CoV-2 viral infection. The imbalanced cellular defense system against oxidative stress commonly associated with aging could explain the increased occurrence of more severe SARS-CoV-2 illness in seniors and in patients with underlying health conditions. Based on the results from this study, we propose that antioxidants such as N-acetyl-L-cysteine, resveratrol, or Vitamin E in combination with antiinflammatory drug could be used to control excess ROS and cytokines in patients with severe COVID-19.

4.
Bioactive Materials ; 2022.
Article in English | ScienceDirect | ID: covidwho-1821146

ABSTRACT

The ongoing pandemic caused by the novel coronavirus, SARS-CoV-2, is influencing global health. Moreover, there is a major threat of future coronaviruses affecting the entire world in a similar, or even more dreadful, manner. Therefore, effective and biocompatible therapeutic options against coronaviruses are urgently needed. To address this challenge, medical specialists require a well-informed and safe approach to treating human coronaviruses (HCoVs). Herein, an environmental friendly approach for viral inactivation, based on plasma technology, was considered. A microwave plasma system was employed for the generation of the high amount of gaseous nitric oxide to prepare nitric oxide enriched plasma-activated water (NO-PAW), the effects of which on coronaviruses, have not been reported to date. To determine these effects, alpha-HCoV-229E was used in an experimental model. We found that NO-PAW treatment effectively inhibited coronavirus infection in host lung cells, visualized by evaluating the cytopathic effect and expression level of spike proteins. Interestingly, NO-PAW showed minimal toxicity towards lung host cells, suggesting its potential for therapeutic application. Moreover, this new approach resulted in viral inactivation and greatly improved the gene levels involved in host antiviral responses. Together, our findings provide evidence of an initiation point for further progress toward the clinical development of antiviral treatments, including such coronaviruses.

5.
Clinical & Translational Immunology ; 11(4):15, 2022.
Article in English | Web of Science | ID: covidwho-1820890

ABSTRACT

Background and objectives. Because of its beneficial off-target effects against non-mycobacterial infectious diseases, bacillus Calmette-Guerin (BCG) vaccination might be an accessible early intervention to boost protection against novel pathogens. Multiple epidemiological studies and randomised controlled trials (RCTs) are investigating the protective effect of BCG against coronavirus disease 2019 (COVID-19). Using samples from participants in a placebo-controlled RCT aiming to determine whether BCG vaccination reduces the incidence and severity of COVID-19, we investigated the immunomodulatory effects of BCG on in vitro immune responses to SARS-CoV-2. Methods. This study used peripheral blood taken from participants in the multicentre RCT and BCG vaccination to reduce the impact of COVID-19 on healthcare workers (BRACE trial). The whole blood taken from BRACE trial participants was stimulated with 7-irradiated SARS-CoV-2-infected or mock-infected Vero cell supernatant. Cytokine responses were measured by multiplex cytokine analysis, and single-cell immunophenotyping was made by flow cytometry. Results. BCG vaccination, but not placebo vaccination, reduced SARS-CoV-2-induced secretion of cytokines known to be associated with severe COVID-19, including IL-6, TNF-alpha and IL-10. In addition, BCG vaccination promoted an effector memory phenotype in both CD4(+) and CD8(+) T cells, and an activation of eosinophils in response to SARS-CoV-2. Conclusions. The immunomodulatory signature of BCG's off-target effects on SARS-CoV-2 is consistent with a protective immune response against severe COVID-19.

6.
Indoor and Built Environment ; : 19, 2022.
Article in English | Web of Science | ID: covidwho-1819962

ABSTRACT

The novel corona respiratory viruses usually leave the host via droplets and float in the air or settle down. Medically, the decay characteristics of aerosolized viruses have been simulated and measured by atomizing suspensions into air, but there has been no systematic study on the effect of ambient temperature and humidity. In this study, we collected experimental data from existing medical studies, then introduced and calculated the initial decay constant (k(1)) and the secondary decay constant (k(2)) based on these data as a unified standard to quantify the decay process of the aerosolized viruses. Additionally, the influence of various factors on the decay constant of respiratory viruses in the air was statistically analyzed. The results showed that the phase decay of aerosolized viruses was very evident, and k(1) (0.1 similar to 50) was usually one order of magnitude higher than k(2) (0.005 similar to 3.2). Furthermore, the relationship between the decay constant and the survival rate of viruses, representing the risk of virus transmission, and the decay time constants, reflecting the effective period of prevention and control, was discussed. According to the decay law, the main contradiction between virus transmission and epidemic prevention and control at different time nodes was pointed out, and scientific measures to reduce the transmission risk in the built environment were recommended.

7.
Cell Stem Cell ; 29(5):810-825.e8, 2022.
Article in English | ScienceDirect | ID: covidwho-1819607

ABSTRACT

Summary Trophoblast organoids derived from placental villi provide a 3D model system of human placental development, but access to first-trimester tissues is limited. Here, we report that trophoblast stem cells isolated from naive human pluripotent stem cells (hPSCs) can efficiently self-organize into 3D stem-cell-derived trophoblast organoids (SC-TOs) with a villous architecture similar to primary trophoblast organoids. Single-cell transcriptome analysis reveals the presence of distinct cytotrophoblast and syncytiotrophoblast clusters and a small cluster of extravillous trophoblasts, which closely correspond to trophoblast identities in the post-implantation embryo. These organoid cultures display clonal X chromosome inactivation patterns previously described in the human placenta. We further demonstrate that SC-TOs exhibit selective vulnerability to emerging pathogens (SARS-CoV-2 and Zika virus), which correlates with expression levels of their respective entry factors. The generation of trophoblast organoids from naive hPSCs provides an accessible 3D model system of the developing placenta and its susceptibility to emerging pathogens.

8.
Asia-Pacific Journal of Molecular Biology and Biotechnology ; 29:57, 2021.
Article in English | ProQuest Central | ID: covidwho-1812906

ABSTRACT

The novel human coronavirus (CoV) 2019 known as COVID-19, similar to previous CoVs infections outbreaks has posed a serious and an unprecedented challenge on the entire health care system in the world, that needs aggressive preventive and easily accessible measures, policies for effective regular disinfection. Rampant use of disinfectants may pose toxicity to human, environmental hazards and, in some cases, decrease effectiveness and development of resistance due to other ingredients in the disinfectant agents. This review comprehensively highlights the effects of physical and chemical countermeasures and their related potential toxicity on human and environment. The study reveals that physical inactivation especially the effects of temperature, humidity and light mostly ultraviolet-C (UV-C), have significantly demonstrated proven efficacy in reducing the spread of CoV infections. Similarly, chemical countermeasures especially alcoholand iodine-based disinfecting agents have shown potentials inhibition against the survival of the viruses and other pathogenic micro-organisms on surfaces. Large number of disinfectants were reported to contain corrosive chemicals that are toxic to humans especially children and destroy the environment due to unhealthy accumulation and pollution, and other additional ingredients having potentials to develop resistance and decrease effectiveness of the disinfectants. This review sumarizes the imporatnce of physical and chemical preventive countermeasures currently in use against CoV infections for further modifications and translational study to design improved disinfecting agents.

9.
Journal of New Materials for Electrochemical Systems ; 24(4):293-296, 2021.
Article in English | Web of Science | ID: covidwho-1811435

ABSTRACT

As human knowledge has increased, the efficacy and precision of tools to solve clinical problems have also increased. The challenge of COVID-19 has posed a significant threat to human life and reflects the need to upgrade existing technologies and make treatments more precise. Since the corona virus particle is in the nanometer range, the need for a device with accuracy beyond the nanometer range is apparent to control and eliminate it. Using Picosecond Pulsed Electric Fields (PPEF) could be a good antiviral picotechnology candidate. PPEF energy can (1) increase the innate immunity function of polymorphonuclear neutrophils, (2) destroy bacteria and other pathogens, and (3) potentially inactivate viral particles. This characteristic of PPEFs has already been used in the food industry. Both PPEF and nanosecond PEF technology is being used to treat cancer in research animals and has reached the stage of pre-clinical and clinical human trials with use in clinical practice soon to follow. Applying advanced PPEF technology against COVID-19 should provide new opportunities for effective human antiviral treatment. .

10.
Molecules ; 27(8):2560, 2022.
Article in English | ProQuest Central | ID: covidwho-1810042

ABSTRACT

Herpes simplex type 2 (HSV-2) infection causes a significant life-long disease. Long-term side effects of antiviral drugs can lead to the emergence of drug resistance. Thus, propolis, a natural product derived from beehives, has been proposed to prevent or treat HSV-2 infections. Unfortunately, therapeutic applications of propolis are still limited due its poor solubility. To overcome this, a nanoparticle-based drug delivery system was employed. An ethanolic extract of propolis (EEP) was encapsulated in nanoparticles composed of poly(lactic-co-glycolic acid) and chitosan using a modified oil-in-water single emulsion by using the solvent evaporation method. The produced nanoparticles (EEP-NPs) had a spherical shape with a size of ~450 nm and presented satisfactory physicochemical properties, including positively charged surface (38.05 ± 7.65 mV), high entrapment efficiency (79.89 ± 13.92%), and sustained release profile. Moreover, EEP-NPs were less cytotoxic on Vero cells and exhibited anti-HSV-2 activity. EEP-NPs had a direct effect on the inactivation of viral particles, and also disrupted the virion entry and release from the host cells. A significant decrease in the expression levels of the HSV-2 replication-related genes (ICP4, ICP27, and gB) was also observed. Our study suggests that EEP-NPs provide a strong anti-HSV-2 activity and serve as a promising platform for the treatment of HSV-2 infections.

11.
Journal of the Korean Physical Society ; 80(8):817-851, 2022.
Article in English | ProQuest Central | ID: covidwho-1803196

ABSTRACT

Nonthermal biocompatible plasma (NBP) sources operating in atmospheric pressure environments and their characteristics can be used for plasma bioscience, medicine, and hygiene applications, especially for COVID-19 and citizen. This review surveyed the various NBP sources, including a plasma jet, micro-DBD (dielectric barrier discharge) and nanosecond discharged plasma. The electron temperatures and the plasma densities, which are produced using dielectric barrier discharged electrode systems, can be characterized as 0.7 ~ 1.8 eV and (3–5) × 1014–15 cm−3, respectively. Herein, we introduce a general schematic view of the plasma ultraviolet photolysis of water molecules for reactive oxygen and nitrogen species (RONS) generation inside biological cells or living tissues, which would be synergistically important with RONS diffusive propagation into cells or tissues. Of the RONS, the hydroxyl radical [OH] and hydrogen peroxide H2O2 species would mainly result in apoptotic cell death with other RONS in plasma bioscience and medicines. The diseased biological protein, cancer, and mutated cells could be treated by using a NBP or plasma activated water (PAW) resulting in their apoptosis for a new paradigm of plasma medicine.

12.
Aims Bioengineering ; 9(2):93-101, 2022.
Article in English | Web of Science | ID: covidwho-1798847

ABSTRACT

The spread of infections, as in the coronavirus pandemic, leads to the desire to perform disinfection measures even in the presence of humans. UVC radiation is known for its strong antimicrobial effect, but it is also harmful to humans. Visible light, on the other hand, does not affect humans and laboratory experiments have already demonstrated that intense visible violet and blue light has a reducing effect on bacteria and viruses. This raises the question of whether the development of pathogen-reducing illumination is feasible for everyday applications. For this purpose, a lighting device with white and violet LEDs is set up to illuminate a work surface with 2,400 lux of white light and additionally with up to 2.5 mW/cm2 of violet light (405 nm). Staphylococci are evenly distributed on the work surface and the decrease in staphylococci concentration is observed over a period of 46 hours. In fact, the staphylococci concentration decreases, but with the white illumination, a 90% reduction occurs only after 34 hours;with the additional violet illumination the necessary irradiation time is shortened to approx. 3.5 hours. Increasing the violet component probably increases the disinfection effect, but the color impression moves further away from white and the low disinfection durations of UVC radiation can nevertheless not be achieved, even with very high violet emissions.

13.
Int J Circumpolar Health ; 81(1): 2064597, 2022 Dec.
Article in English | MEDLINE | ID: covidwho-1795423

ABSTRACT

In the spring of 2020, the Alaska Native Tribal Health Consortium (ANTHC) designed and built a sanitizing treatment system to address shortages of filtering facepiece respirators (FFRs). The design criteria included sanitizing large numbers of FFRs, repeatedly achieving FFR fit test requirements, and deactivating enveloped respiratory viruses, such as SARS-CoV-2. The outcome was the Mobile Sanitizing Trailer (MST), a 20 by 8-foot modified trailer designed to process up to 1,000 FFRs during a standard heat cycle. This paper reports on the MST's ability to: (1) sustain a target temperature, (2) produce tolerable conditions for FFRs as measured by fit factor and (3) successfully deactivate an infectious model virus. We found that the MST reliably and uniformly produced 75 degrees Celsius in the treatment chamber for the prescribed periods. Quantitative analysis showed that the FFRs achieved acceptable post-treatment fit factor even after 18, 60-minute heat cycles. Finally, the treated FFR materials had at least a log 3.0 reduction in viral RNA and no viable virus after 30, 60 or 90 minutes of heat treatment. As a sanitizing treatment during supply shortages, we found the MST a viable option for deactivation of virus and extending the usable life of FFRs.

14.
Mediterr. J. Infect. Microbes Antimicrob. ; 11:8, 2022.
Article in English | Web of Science | ID: covidwho-1792136

ABSTRACT

As Severe acute respiratory syndrome-Coronavirus-2 (SARS-CoV-2) emerged in 2019, scientists sought to find a way of inactivating this new virus to effectively disinfect surfaces, air, hands, etc. The first proposed manners were on the basis of chemical disinfectants such as chlorine and bleach, however, application of these methods can result in some hazards for human beings and the environment. Therefore, new methods such as ultraviolet (UV) radiation were recommended. Not only these new methods can accelerate the inactivation of SARS-CoV-2 in a more efficient way, their hazards and side effects are also less when compared to chlorine-based disinfectants. In this review, we discussed the utilization of UV-C, hydrogen peroxide, ozone, and cold plasma as new, nonthermal methods to disinfect personal protective equipment, air, and surfaces in hospitals, since hospitals were one of the major sources of Coronavirus disease-2019 infection and members of health care team were highly prone to being infected.

15.
Microbiology Spectrum ; 10(1):16, 2022.
Article in English | Web of Science | ID: covidwho-1790428

ABSTRACT

The vascular endothelial injury occurs in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections, but the mechanisms are poorly understood. We sought to determine the frequency and type of cytokine elevations and their relationship to endothelial injury induced by plasma from patients with SARS-CoV-2 versus controls. Plasma from eight consecutively enrolled patients hospitalized with acute SARS-CoV-2 infection was compared to controls. Endothelial cell (EC) barrier integrity was evaluated using ECIS (electric cell-substrate impedance sensing) on human lung microvascular EC. Plasma from all SARS-CoV-2 but none from controls decreased transendothelial resistance to a greater degree than that produced by tumor necrosis factor-alpha (TNF-alpha), the positive control for the assay. Thrombin, angiopoietin 2 (Ang2), and vascular endothelial growth factor (VEGF), complement factor C3a and C5a, and spike protein increased endothelial permeability, but to a lesser extent and a shorter duration when compared to SARS-CoV-2 plasma. Analysis of Ang2, VEGF, and 15 cytokines measured in plasma revealed striking patient-to-patient variability within the SARS-CoV-2 patients. Pretreatment with thrombin inhibitors, single, or combinations of neutralizing antibodies against cytokines, Ca3 and C5a receptor antagonists, or with ACE2 antibody failed to lessen the SARS-CoV-2 plasma-induced EC permeability. The EC barrier destructive effects of plasma from patients with SARS-CoV-2 were susceptible to heat inactivation. Plasma from patients hospitalized with acute SARS-CoV-2 infection uniformly disrupts lung microvascular integrity. No predicted single, or set of, cytokine(s) accounted for the enhanced vascular permeability, although the factor(s) were heat-labile. A still unidentified but potent circulating factor(s) appears to cause the EC disruption in SARS-CoV-2 infected patients. IMPORTANCE Lung vascular endothelial injury in SARS-CoV-2 patients is one of the most important causes of morbidity and mortality and has been linked to more severe complications including acute respiratory distress syndrome (ARDS) and subsequent death due to multiorgan failure. We have demonstrated that in eight consecutive patients with SARS-CoV-2, who were not selected for evidence of endothelial injury, the diluted plasma-induced intense lung microvascular damage, in vitro. Known endothelial barrier-disruptive agents and proposed mediators of increased endothelial permeability in SARS-CoV-2, induced changes in permeability that were smaller in magnitude and shorter in duration than plasma from patients with SARSCoV-2. The effect on endothelial cell permeability of plasma from patients with SARS-CoV-2 was heat-labile. The main plasma factor that causes the increased endothelial permeability remains to be identified. Our study provides a possible approach for future studies to understand the underlying mechanisms leading to vascular injury in SARS-CoV-2 infections.

16.
Nanotechnology Reviews ; 11(1):1555-1569, 2022.
Article in English | ProQuest Central | ID: covidwho-1789224

ABSTRACT

A new virus, the coronavirus (COVID-19), is causing serious respiratory infections in humans. Rapid, specific, and sensitive diagnostic techniques for early-stage detection of SARS-CoV-2 viral protein are developing as a necessary response for effective smart diagnostics, treatment optimization, and exploration of therapeutics with better effectiveness in the fight against the COVID-19 pandemic. Keeping the considerations mentioned above, we propose a new modeling graphene nanocomposite-based biosensing device for detecting COVID-19 at the site of the epidemic as the best way to manage the pandemic. It is important to address the problems of COVID-19 management. With the challenges and aspects of COVID-19 management in mind, we present in this review a collective approach involving electrochemical COVID-19 biosensing required for early-stage COVID-19 diagnosis and the direct interaction with viral surface glycoproteins and metal nanoparticles that can enter cells and neutralize viruses by interacting directly with the viral genome (ribonucleic acid), which identifies the COVID-19 spike protein and antiviral procedure including virus inactivation, host cell receptor inactivation, electrostatic entrapment, and physicochemical destruction of viral species by nucleotide ring opening. The interactions between the graphene composite and virus may be boosted by functionalization of the carbon surface and decoration of metallic components that enhance these interactions. Our proposed new modeling molecular dynamic simulation-based neutralizing mechanism and real-time detection of COVID-19 on graphene nanocomposite-based biosensors are suitable for point-of-care diagnostic applications, and this sensing platform can be modified for the early diagnosis of severe viral infections using real samples. For the potential application, the suggested one is the chemical reaction and bond breaking between the metallic component and molecule of COVID19 with computer simulation data.

17.
J Appl Microbiol ; 132(4): 2625-2632, 2022 Apr.
Article in English | MEDLINE | ID: covidwho-1788869

ABSTRACT

AIMS: Viral pathogens are the primary agents in bovine respiratory disease cases, and there is no direct effective antiviral drug application. Thymbra is a genus of oregano commonly found in Turkey. The primary component (34.9%) of the extract obtained from Thymbra spicata L. is the carvacrol which is used in traditional medicine. This study evaluates the potential antiviral activity and inactivation efficiency of T. spicata L. extract against bovine respiratory viruses, including BCoV, BPIV-3, BRSV, BVDV and BoHV-1. METHODS AND RESULTS: To evaluate its effect on viral replication, viral titres were taken from infected cells treated with non-cytotoxic T. spicata L. extract concentrations (0.75% and 1.5%, 1.32 and 2.64 µg/ml of carvacrol as active ingredient, respectively) and compared to non-treated infected cells. The viruses were treated directly with 1.5% T. spicata L. extract, and the viral titres were evaluated at certain time points to determine the efficiency of direct inactivation. The number of infectious virions for BCoV, BPIV-3, BRSV, BVDV and BoHV-1 treated with 1.5% T. spicata L. extract were decreased by 99.44%, 100.0%, 94.38%, 99.97% and 99.87%, respectively.T. spicata L. extract strongly inhibits the replication of mentioned viruses in a dose-dependent manner in vitro. In addition, T. spicata L. extract shared direct inactivation efficiency on the mentioned viruses in a time-dependent manner. CONCLUSION: This study shows the antiviral efficiency of T. spicata L. on BRD-related viral agents for the first time. The oregano species T. spicata and its main component, carvacrol, may have a potential for antiviral activity in the alternative treatment of respiratory viral diseases in cattle. SIGNIFICANCE AND IMPACT OF THE STUDY: Given the similarity of replication strategies, obtained data suggest the possible efficiency of T. spicata L. on human respiratory viruses.


Subject(s)
Cattle Diseases , Lamiaceae , Viruses , Animals , Antiviral Agents/pharmacology , Cattle , Plant Extracts/pharmacology
18.
Journal of Photochemistry and Photobiology ; : 100120, 2022.
Article in English | ScienceDirect | ID: covidwho-1778332

ABSTRACT

The quick spreading of the SARS-CoV-2 virus, initiating the global pandemic with a significant impact on economics and health, highlighted an urgent need for effective and sustainable restriction mechanisms of pathogenic microorganisms. UV-C radiation, causing inactivation of many viruses and bacteria, is one of the tools for disinfection of different surfaces, liquids, and air;however, mainly mercury 254 nm line is commonly used for it. In this paper, we report our results of the experiments with newly elaborated special type polychromatic non-mercury UV light sources, having spectral lines in the spectral region from 190 nm to 280 nm. Inactivation tests were performed with both Escherichia coli (E.coli) bacteria and Semliki Forest virus (SFV) as a representative of human enveloped RNA viruses. In addition, the effect of prepared lamps on virus samples in liquid and dry form (dried virus-containing solution) was tested. Reduction of 4 log10 of E.coli was obtained after 10 minutes of irradiation with both thallium-antimony and arsenic high-frequency electrodeless lamps. High reduction results for the arsenic light source demonstrated sensitivity of E. coli to wavelengths below 230 nm, including spectral lines around 200 nm. For the Semliki Forest virus, the thallium-antimony light source showed virus inactivation efficiency with a high virus reduction rate in the range of 3.10 to > 4.99 log10 within 5 minutes of exposure. Thus, the new thallium-antimony light source showed the most promising disinfection effect in bacteria and viruses, and arsenic light sources for bacteria inactivation, opening doors for many applications in disinfection systems, including for pathogenic human RNA viruses.

19.
Food Microbiology ; : 104036, 2022.
Article in English | ScienceDirect | ID: covidwho-1773312

ABSTRACT

Severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) is primarily transmitted from human to human via droplets and aerosols. While transmission via contaminated surfaces is also considered possible, the overall risk of this transmission route is assumed to be low. Nevertheless, transmission through contaminated drinking glasses may pose an increased risk as the glass is in direct contact with the mouth and oral cavity. Using human coronavirus 229E (HCoV-229E) as surrogate for SARS-CoV-2, this study examined coronavirus stability on glass, inactivation by dishwashing detergents, and virus elimination by a manual glass scrubbing device. Infectious HCoV-229E was recovered from glass up to 7 and 21 days storage under daylight and dark conditions, respectively. Near complete inactivation of HCoV-229E (>4 log10 reduction) was observed after incubation with two common dishwashing detergents at room temperature for 15 s, whereas incubation at 43 °C for 60 s was necessary for a third detergent to achieve a similar titer reduction. The virus was efficiently removed from contaminated drinking glasses using a manual glass scrubbing device in accordance with German standard DIN 6653-3. The results confirm that coronaviruses are relatively stable on glass, but indicate that common manual dishwashing procedures can efficiently eliminate coronaviruses from drinking glasses.

20.
Nanomaterials (Basel) ; 12(6)2022 Mar 18.
Article in English | MEDLINE | ID: covidwho-1765798

ABSTRACT

All Muslim pilgrims must wear Ihram clothes during the Hajj and Umrah seasons, which presents a great challenge regarding how to eliminate the spread of microbes attached to the cotton fabric of Ihram from the surrounding environment. Targeted fashion research of the recent past presents a new industrial treatment, which has led us to study the impact of heat directed from an atmospheric pressure plasma jet (APPJ), coupled with photocatalytic nanomaterials, for the antibacterial treatment of Escherichia coli (E. coli) attached to cotton fabric samples, to improve pollutant remediation. The average rates of heat transfer to the bacterial colonies attached to cotton fabric samples, as a function of the laminar mode, were 230 and 77 mW for dry and wet argon discharges, respectively. The jet temperatures (TJ) and heat transfer (QH) decreased more for wet argon discharge than for dry argon discharge. This is because, due to the wettability by TiO2 photocatalyst concentration dosage increases from 0 to 0.5 g L-1, a proportion of the energy from the APPJ photons is expended in overcoming the bandgap of TiO2 and is used in the creation of electron-hole pairs. In the Weibull deactivation function used for the investigation of the antibacterial treatment of E. coli microbes attached to cotton fabric samples, the deactivation kinetic rate of E. coli increased from 0.0065 to 0.0152 min-1 as the TiO2 precursor concentration increased. This means that the sterilization rate increased despite (TJ) and (QH) decreasing as the wettability by TiO2 photocatalyst increases. This may be due to photocatalytic disinfection and the generation of active substances, in addition to the effect of the incident plume of the non-thermal jet.

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