Article

Virus Isolation from the First Patient with SARS-CoV-2 in Korea

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Abstract

Novel coronavirus (SARS-CoV-2) is found to cause a large outbreak started from Wuhan since December 2019 in China and SARS-CoV-2 infections have been reported with epidemiological linkage to China in 25 countries until now. We isolated SARS-CoV-2 from the oropharyngeal sample obtained from the patient with the first laboratory-confirmed SARS-CoV-2 infection in Korea. Cytopathic effects of SARS-CoV-2 in the Vero cell cultures were confluent 3 days after the first blind passage of the sample. Coronavirus was confirmed with spherical particle having a fringe reminiscent of crown on transmission electron microscopy. Phylogenetic analyses of whole genome sequences showed that it clustered with other SARS-CoV-2 reported from Wuhan.

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... Although the qRT-PCR technique is mature and accurate, it is time consuming, expensive in terms of the equipment and reagents, and requires trained technicians for complex sample preparation and testing procedures. These defects restrict the application of the platform to the central laboratory and occasionally lead to inaccurate results owing to insufficient materials or sample transportation problems, thus making the method unsuitable for the rapid, low-cost, and accurate detection of COVID-19 Liu R. et al., 2020;Kim Y. J. et al., 2020). Similar to qRT-PCR, RT-LAMP is based on a set of four primers and the strand displacement of active reverse transcriptase. ...
... It often requires tremendous labor to screen for the correct antibody pairs. The selected antibody needs to be specific to avoid crossreaction with severe acute respiratory syndrome coronavirus (SARS-CoV) or middle east respiratory syndrome coronavirus (MERS-CoV) because the essential functional domains of SARS-CoV-2 are highly homologous (Park et al., 2020). Kim et al. (2021) used phage display technology (Ledsgaard et al., 2018) to screen single-chain variable fragment (scFv)-crystallizable fragment (Fc) fusion proteins as specific antibodies for the detection of SARS-CoV-2 N protein. ...
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Article
The outbreak of the coronavirus disease 2019 (COVID-19) has resulted in enormous losses worldwide. Through effective control measures and vaccination, prevention and curbing have proven significantly effective; however, the disease has still not been eliminated. Therefore, it is necessary to develop a simple, convenient, and rapid detection strategy for controlling disease recurrence and transmission. Taking advantage of their low-cost and simple operation, point-of-care test (POCT) kits for COVID-19 based on the lateral flow assay (LFA) chemistry have become one of the most convenient and widely used screening tools for pathogens in hospitals and at home. In this review, we introduce essential features of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus, compare existing detection methods, and focus on the principles, merits and limitations of the LFAs based on viral nucleic acids, antigens, and corresponding antibodies. A systematic comparison was realized through summarization and analyses, providing a comprehensive demonstration of the LFA technology and insights into preventing and curbing the COVID-19 pandemic.
... MW466791.1, S clade) [15], and SARS-CoV-2/human/KOR/NCCP 43390/2021 (GenBank ID. OL966962.1, ...
... Neutralizing activity against SARS-CoV-2 WT and the Delta variant was investigated in FRNT 50 using serum samples from the Conv6mVx1, Conv18mVx1, Con-v18mVx2, NonConvVx1, and NonConvVx2 groups. 15] in the Con-v18mVx1 group, adjusted P < 0.001) (Fig. 1c). a IgG-binding activities measured using an enzyme-linked immunosorbent assay. ...
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Article
Background Practical guidance is needed regarding the vaccination of coronavirus disease 2019 (COVID-19) convalescent individuals in resource-limited countries. It includes the number of vaccine doses that should be given to unvaccinated patients who experienced COVID-19 early in the pandemic. Methods We recruited COVID-19 convalescent individuals who received one or two doses of an mRNA vaccine within 6 or around 18 months after a diagnosis of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection. Their samples were assessed for IgG-binding or neutralizing activity and cell-mediated immune responses against SARS-CoV-2 wild-type and variants of concern. Results A total of 43 COVID-19 convalescent individuals were analyzed in the present study. The results showed that humoral and cellular immune responses against SARS-CoV-2 wild-type and variants of concern, including the Omicron variant, were comparable among patients vaccinated within 6 versus around 18 months. A second dose of vaccine did not significantly increase immune responses. Conclusion One dose of mRNA vaccine should be considered sufficient to elicit a broad immune response even around 18 months after a COVID-19 diagnosis.
... The MHLW (Ministry of Health, Labor, and welfare) of Japan identified a novel coronavirus patient (COVID-19) from the similar origin on 15 January, 2020. The first novel coronavirus outbreak in Korea, similar in Wuhan, China, was verified by the National IHR Focal Point (NFP) for Korea on January 20, 2020 [13,14]. ...
... This was found that size of particles of virus ranging from 70-90 nm And most commonly found in Intracellular organelles [2]. It is determined that Coronavirus Contains a single positive sense-RNA strand that is similar to host messenger RNA, Which is about 26 to 30 kb [13,66]. The RNA of COVID-19 has single-stranded RNA with positive charge having 4 major types of structural proteins that are envelopeprotein (E), Transmembrane protein (M), Nucleocapsid protein (N), and Spike protein (S) [67]. ...
... SARS-CoV-2, as a cell-cytotoxic virus, during part of its replication cycle, leads to the death and damage of cells and tissues infected [20]. As seen in SARS-CoV patients [21], infection and proliferation of the virus in epithelial cells of the airway system can increase virus-associated pyroptosis accompanied by vascular leakage [22]. ...
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Article
Severe Acute Respiratory Syndrome-Coronavirus 2 (SARS-CoV-2) that causes COVID-19 disease could progress to Acute Respiratory Distress Syndrome (ARDS). The immune cells' migration in response to the virus leads to cell death by releasing oxidizing free radicals. These oxidizing free radicals mediate NF-κB (Nuclear Factor 'kappa-light-chain-enhancer' of activated B-cells) activation and induce transcription of cytokine-producing genes that eventually causes cytokine storm and septic shock. The over-expression of oxidative stress and enhancing Reactive Oxygen Species (ROS) and Reactive Nitrogen Species (RNS) production activate transcription factors like NF-κB. So repeating this cycle intensifies the host's inflammatory responses. In this way, antioxidants as compounds that inhibit oxidation by terminating chain reactions are suggested to alleviate COVID-19 symptoms. In the present review study, the pathogenesis of the virus, the virus immunopathology, and the balance between immune responses and oxidative stress are discussed. Also, in this review, due to the importance of oxidative stress in the pathogenesis of the disease, some of the most important antioxidant agents whose therapeutic effects have been shown in improving many viral infections, ARDS, and acute lung injury, are recommended to improve the patient's condition infected with SARS-CoV-2. Besides, the recent COVID-19 clinical studies in this field are summarized in this review article. In the present review study, the pathogenesis of the virus, the virus immunopathology, and the balance between immune responses and oxidative stress are discussed. Also, in this review, due to the importance of oxidative stress in the pathogenesis of the disease, some of the most important antioxidant agents whose therapeutic effects have been shown in improving many viral infections, ARDS, and acute lung injury, are recommended to improve the patient's condition infected with SARS-CoV-2. Besides, the recent COVID-19 clinical studies in this field are summarized in this review article. According to these studies, melatonin through promoting sleep quality, decreasing vascular permeability, reducing anxiety, and regulating blood pressure; vitamin C through decreasing the mortality rates and the requirement for mechanical ventilation; glutathione through decreasing respiratory distress in the pneumonia of COVID-19 patients; and high selenium levels could improve the COVID-19 patients' clinical outcomes.
... Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is thought to have originated as a parasitic virus in bats, which has evolved to be able to replicate and spread in human cells. 1 It is known to use angiotensin-converting enzyme 2 (ACE2) receptor, transmembrane protease serine subtype 2 (TMPRSS2), and Furin proteins as pathways to enter human cells. When the S2 domain of the SARS-CoV-2 spike binds to the ACE2 receptor of a human cell, TMPRSS2 cuts the S2 domain, and the S1 domain of the virus binds to Furin protein to allow entry to human cells. ...
Article
Background: In some patients, coronavirus disease 2019 (COVID-19) is accompanied by loss of smell and taste, and this has been reportedly associated with exposure to air pollutants. This study investigated the relationship between the occurrence of chemosensory dysfunction in COVID-19 patients and air pollutant concentrations in Korea. Methods: Information on the clinical symptom of chemosensory dysfunction, the date of diagnosis, residential area, age, and sex of 60,194 confirmed COVID-19 cases reported to the Korea Disease Control and Prevention Agency from January 20 to December 31, 2020 was collected. In addition, the daily average concentration of air pollutants for a week in the patients' residential area was collected from the Ministry of Environment based on the date of diagnosis of COVID-19. A binomial logistic regression model, using age and gender, standardized smoking rate, number of outpatient visits, 24-hour mean temperature and relative humidity at the regional level as covariates, was used to determine the effect of air pollution on chemosensory dysfunction. Results: Symptoms of chemosensory dysfunction were most frequent among patients in their 20s and 30s, and occurred more frequently in large cities. The logistic analysis showed that the concentration of particulate matter 10 (PM10) and 2.5 (PM2.5) up to 2 days before the diagnosis of COVID-19 and the concentration of sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), and ozone (O3) at least 7 days before the diagnosis of COVID-19 affected the development of chemosensory dysfunction. In the logistic regression model adjusted for age, sex, standardized smoking rate, number of outpatient visits, and daily average temperature and relative humidity, it was found that an increase in the interquartile range of PM10, PM2.5, SO2, NO2, and CO on the day of diagnosis increased the incidence of chemosensory dysfunction 1.10, 1.10, 1.17, 1.31, and 1.19-fold, respectively. In contrast, the O3 concentration had a negative association with chemosensory dysfunction. Conclusion: High concentrations of air pollutants such as PM10, PM2.5, SO2, NO2, and CO on the day of diagnosis increased the risk of developing chemosensory dysfunction from COVID-19 infection. This result underscores the need to actively prevent exposure to air pollution and prevent COVID-19 infection. In addition, policies that regulate activities and products that create high amounts of harmful environmental wastes may help in promoting better health for all during COVID-19 pandemic.
... The SARS-CoV-2 virus, whose diameter has been reported within 60-150 nm (Park et al., 2019;Kim et al., 2020;Ren et al., 2020;Zhu et al., 2020), is emitted in respiratory droplets during expiration while breathing, talking, sneezing and coughing. As the airborne particles persist in the air, their size varies strongly, depending on environmental conditions. ...
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Wearing a medical mask for longer than the manufacturer’s recommended 4 h would reduce the number of masks used and limit their environmental impact. The objective of this study was to determine if a medical mask could be worn for an extended period of time by simulating different wearing conditions. A simulator was developed to reproducibly study various experimental conditions (wearing time, breathing pattern, mask fit, inhaled air humidity) by placing the masks on a 3D replica of the upper airways connected to a respiratory pump. Medical mask performance was determined by assessing normative requirements: bacterial filtration and breathability. No impact on performance was observed for wearing times from 2h to 8h. Similarly, when simulating moderate respiratory effort or at rest, various humidity levels in the inhaled air or different fitting conditions, no influence on performance was found. These results imply that none of these experimental conditions appear to have a significant impact on mask performance. In conclusion some medical masks can be used for up to 8 h under different wearing conditions without significant decrease in their bacterial filtration and breathability performance. This recommendation of a possible rise of usage duration would limit mask waste, and thus environmental consequence.
... This mechanism promotes viral infected immune cell trafficking to the CNS via a "Trojan horse" [50]. However, at the time of viral replication in the host cells, the impairment may be created due to SARS-CoV-2 (cytoplasmic virus), which stimulates the discharge of damage-associated molecular patterns (DAMPs) [51]. Damage-associated molecular patterns (DAMPs) are endogenous compounds released through impaired cells that interact with a pattern-recognition receptor (PRR), which stimulates the endothelial cells, neighboring epithelial cells like macrophages, and a high inflammatory condition. ...
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Article
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a human coronavirus (HCoV) that has created a pandemic situation worldwide as COVID-19. This virus can invade human cells via angiotensin-converting enzyme 2 (ACE2) receptor-based mechanisms, affecting the human respiratory tract. However, several reports of neurological symptoms suggest a neuroinvasive development of coronavirus. SARS-CoV-2 can damage the brain via several routes, along with direct neural cell infection with the coronavirus. The chronic inflammatory reactions surge the brain with proinflammatory elements, damaging the neural cells, causing brain ischemia associated with other health issues. SARS-CoV-2 exhibited neuropsychiatric and neurological manifestations, including cognitive impairment, depression, dizziness, delirium, and disturbed sleep. These symptoms show nervous tissue damage that enhances the occurrence of neurodegenerative disorders and aids dementia. SARS-CoV-2 has been seen in brain necropsy and isolated from the cerebrospinal fluid of COVID-19 patients. The associated inflammatory reaction in some COVID-19 patients has increased proinflammatory cytokines, which have been investigated as a prognostic factor. Therefore, the immunogenic changes observed in Parkinson's and Alzheimer's patients include their pathogenetic role. Inflammatory events have been an important pathophysiological feature of neurodegenerative diseases (NDs) such as Parkinson's and Alzheimer's. The neuroinflammation observed in AD has exacerbated the Aβ burden and tau hyperphosphorylation. The resident microglia and other immune cells are responsible for the enhanced burden of Aβ and subsequently mediate tau phosphorylation and ultimately disease progression. Similarly, neuroinflammation also plays a key role in the progression of PD. Several studies have demonstrated an interplay between neuroinflammation and pathogenic mechanisms of PD. The dynamic proinflammation stage guides the accumulation of α-synuclein and neurodegenerative progression. Besides, few viruses may have a role as stimulators and generate a cross-autoimmune response for α-synuclein.
... There are many changes in the metabolic and nuclear activities of virus infected cell (Fig. 1). Approximate calculation implicates that, production of virion particles per infected cell (viral burst size is not applicable because virion come out by budding from the host cells) is about 104 to 105 [28,29]. Synthesis of this huge amount of virion particles exploits the cellular metabolic pathways [30,31], including glycolysis, amino acids and nucleotides biosynthesis. ...
Article
COVID-19 has caused numerous deaths as well as imposed social isolation and upheaval world-wide. Although, the genome and the composition of the virus, the entry process and replication mechanisms are well investigated from by several laboratories across the world, there are many unknown remaining questions. For example, what are the functions of membrane lipids during entry, packaging and exit of virus particles? Also, the metabolic aspects of the infected tissue cells are poorly understood. In the course of virus replication and formation of virus particles within the host cell, the enhanced metabolic activities of the host is directly proportional to viral loads. The epigenetic landscape of the host cells is also altered, particularly the expression/repression of genes associated with cellular metabolism as well as cellular processes that are antagonistic to the virus. Metabolic pathways are enzyme driven processes and the expression profile and mechanism of regulations of the respective genes encoding those enzymes during the course of pathogen invasion might be highly informative on the course of the disease. Recently, the metabolic profile of the patients' sera have been analysed from few patients. In view of this, and to gain further insights into the roles that epigenetic mechanisms might play in this scenario in regulation of metabolic pathways during the progression of COVID-19 are discussed and summarised in this contribution for ensuring best therapy.
... CoV is a singlestranded positive sense, enveloped RNA virus with a genome size of 26-32 kb [24], while SARS-CoV-2 has a genome size of 29.8-29.9 kb [16] and a diameter of SARS-CoV-2 virion could be varied between 60-140 nm [49], however, under electron microscopy, SARS CoV-2 with virus particle sizes varying from 70-90 nm was observed under a broad range of intracellular organelles [28]. The genome can function as mRNAs, and its purified genome is infectious in nature [17], which was also a concern in terms of biosafety both inside and outside the laboratory. ...
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Severe acute respiratory syndrome coronavirus 2, SARS-CoV-2 (COVID-19) infection emerged in Wuhan city of China, December 2019 and subsequently WHO announced COVID-19 pandemic. In the absence of effective antiviral drugs, change in genomic make-up which leads to evolution of new variant, effective biosafety measure in place, front line health care workers or laboratory personnel engaged in diagnosis and research are always at risk. As per the scientific risk assessments, the SARS-CoV-2 comes under Risk group 3 pathogens, and to prevent laboratory-acquired infections and disease transmission in the local population and environment, adequate biosafety containment levels are required. Therefore, non propagative work and diagnosis of SARS-CoV-2 with inactivated samples should be performed at least under Biosafety Level 2 (BSL2), while diagnosis with non-inactivated samples should be carried out under BSL3 or BSL2 with inward unidirectional air flow along with BSL3 safety equipments and work practices. However, SARS-CoV-2 culture and isolation, as well as research and development activities, must take place inside the BSL3 containment facility. We attempted to establish adequate and efficient biosafety strategies for avoiding SARS-CoV-2 infections within the laboratory. This may be accomplished by conducting a systematic and comprehensive biosafety risk assessment on a continuous basis in order to cope with evolving risks in the laboratory setting. Furthermore, the healthcare workers in hospital or researchers in the laboratories may be unaware of the possibility of aerosols and droplets mediated infection in the laboratory during the process of centrifugation, vortexing, pipetting, and so on, or by SARS-CoV-2 infected individual during the process of breathing, coughing and sneezing and that aerosolized virus may travel up to 1- 6 m. Therefore, aim of this review is to describe the importance of biosafety measures against SARS-CoV-2 that should be introduced in laboratories undertaking diagnosis/research on SARS-CoV-2/any mutant form of SARS-CoV-2 like omicron suspected samples.
... As done by other groups, Vero E6 cells were used for the isolation of SARS-CoV-2 viruses (Banerjee et al., 2020;Caccuri et al., 2020). A robust virus-induced CPE was observed from the fifth passage onward, similar to the findings of previous reports (Park et al., 2020). The viral titers were around 1 × 10 6 TCID 50 /mL in final passages for all the isolates (Figures 1A,B), similar to the titers reported by other groups (Harcourt et al., 2020a;Brandolini et al., 2021). ...
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The emergence of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) as a serious pandemic has altered the global socioeconomic dynamics. The wide prevalence, high death counts, and rapid emergence of new variants urge for the establishment of research infrastructure to facilitate the rapid development of efficient therapeutic modalities and preventive measures. In agreement with this, SARS-CoV-2 strains were isolated from patient swab samples collected during the first COVID-19 wave in Odisha, India. The viral isolates were adapted to in vitro cultures and further characterized to identify strain-specific variations in viral growth characteristics. The neutralization susceptibility of viral isolates to vaccine-induced antibodies was determined using sera from individuals vaccinated in the Government-run vaccine drive in India. The major goal was to isolate and adapt SARS-CoV-2 viruses in cell culture with minimum modifications to facilitate research activities involved in the understanding of the molecular virology, host–virus interactions, drug discovery, and animal challenge models that eventually contribute toward the development of reliable therapeutics.
... 7,31 The active replication of the virus and its release generates an increase in the plasma levels of angiotensin II, which suggests an imbalance in the renin angiotensin system. 32 In turn, the cytopathic activity of the virus induces the lysis of cells, 33 which, together with angiotensin II, induces a strong immune response; the triggering of a storm of inflammatory cytokines such as IL-1β, IL-6, IP-10, TNF-α, IL-8, IFN-γ, MIP1α, MIP1β, and MCP1 has been observed in patients with moderate and severe COVID-19-These cytokines further activate immune cells and increase the pulmonary infiltration that can develop ARDS with significant lung damage that can culminate in the death of the patient. 24,34 On the other hand, the early production of some cytokines, such as IL-17A and IFN type I and III, may tend to a favourable resolution of the disease, since these are increased in those patients who manage to recover without squealed, compared to the critically ill. ...
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Article
At the end of 2019, an outbreak of a severe respiratory disease occurred in Wuhan China, and an increase in cases of unknown pneumonia was alerted. In January 2020, a new coronavirus named SARS-CoV-2 was identified as the cause. The virus spreads primarily through the respiratory tract, and lymphopenia and cytokine storms have been observed in severely ill patients. This suggests the existence of an immune dysregulation as an accompanying event during a serious illness caused by this virus. Natural killer (NK) cells are innate immune responders, critical for virus shedding and immunomodulation. Despite its importance in viral infections, the contribution of NK cells in the fight against SARS-CoV-2 has yet to be deciphered. Different studies in patients with COVID-19 suggest a significant reduction in the number and function of NK cells due to their exhaustion. In this review, we summarize the current understanding of how NK cells respond to SARS-CoV-2 infection.
... Though the SARS-CoV-2 diameter has been reported within 60−150 nm (Kim et al., 2020;Park et al., 2019;Ren et al., 2020;Zhu et al., 2020), respiratory viruses are emitted from the respiratory tracts attached to droplets in the respiratory secretions during respiratory activities. Particles generated by respiratory activities range from 10 nm to 500 µm (Gralton et al., 2011). ...
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Article
Reusability of masks is a rising environmental concern. Community face masks present a more eco-friendly option as they can be washed and reused several times. The potential reuse of single use medical face masks is also of interest. In this work, the impact of 20 wash cycles (at 60 °C with detergent and air-drying) on the particle filtration efficiency (particle size range 0.1-6. 5μm) and breathability of masks was studied. With regards to the performance of new masks, the medical mask had breathability of 31 Pa.cm ⁻² whilst it ranged from 9 to 59 Pa.cm ⁻² for the community face masks. Additionally, for 3μm particles, the filtration efficiency was 99% for the medical mask and ranged from 28%–89% for the community face masks. Mixed fabric masks were able to maintain their performance up to 20 washing cycles. The washed 100% cotton masks were less breathable but with higher filtration efficiency because of shrinkage of the fabric. The washed medical face mask was able to maintain its breathability and filtration efficiency for sizes ≥ 3μm, however the filtration efficiency was significantly reduced for the submicron particles. This was because the presence of detergent caused the loss of electrostatic charges and led to a decrease of the particle collection by the electrostatic forces. All things considered, both the medical face mask and community face masks can be reused several times, with performances in terms of breathability and filtration efficiency (for particle sizes ≥ 3μm) that remain globally little changed after washing.
... The size of the SARS-CoV-2 virion varies between 70 and 90 nanometers [6,7], and an average concentration of the virus in the sputum of 7.0 × 10 6 copies/mL and a maximum of 2 of 19 2.35 × 10 9 copies/mL [8]. Consequently, the viral load occupies 2.14 × 106% del bioaerosol on average. ...
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Article
The global acceptance of the SARS-CoV-2 airborne transmission led to prevention measures based on quality control and air renewal. Among them, carbon dioxide (CO2) measurement has positioned itself as a cost-efficiency, reliable, and straightforward method to assess indoor air renewal indirectly. Through the control of CO2, it is possible to implement and validate the effectiveness of prevention measures to reduce the risk of contagion of respiratory diseases by aerosols. Thanks to the method scalability, CO2 measurement has become the gold standard for diagnosing air quality in shared spaces. Even though collective transport is considered one of the environments with the highest rate of COVID-19 propagation, little research has been done where the air inside vehicles is analyzed. This work explores the generation and accumulation of metabolic CO2 in a tramway (Zaragoza, Spain) operation. Importantly, we propose to use the indicator ppm/person as a basis for comparing environments under different conditions. Our study concludes with an experimental evaluation of the benefit of modifying some parameters of the Heating–Ventilation–Air conditioning (HVAC) system. The study of the particle retention efficiency of the implemented filters shows a poor air cleaning performance that, at present, can be counteracted by opening windows. Seeking a post-pandemic scenario, it will be crucial to seek strategies to improve air quality in public transport to prevent the transmission of infectious diseases.
... Viruses in general have negative charge, at pH 7, but also have patches of different charges due to various surface compounds (Joonaki et al., 2020). [In the following it may be remembered that SARS-Cov-2 probably have a size of 70-90 nm Park et al., 2020), whereas the NMs from the current paper are generally smaller (10-20 nm)]. Recognition can first occur upon interaction with surface receptors typically innate immune pattern recognition receptors (PRRs) (Boraschi et al., 2020), similar to the surface receptors of viruses. ...
Article
Current human research on COVID-19 – SARS-CoV-2 (Severe Acute Respiratory Syndrome-Corona Virus) showed that ACE2 (Angiotensin Converting Enzyme 2) is a functional receptor to which the spike proteins attach. Invertebrates have been exposed to a wide array of threats for millennia and their immune system has evolved to deal with these efficiently. The annelid Enchytraeus crypticus, a standard ecotoxicological species, is an invertebrate species where extensive mechanisms of response studies are available, covering all levels from gene to population responses. Nanomaterials (NMs) are often perceived as invaders (e.g. virus) and can enter the cell covered by a corona, triggering similar responses. We created a database on E. crypticus ACE gene expression, aiming to analyse the potential knowledge transfer between invertebrates and vertebrates. Total exposure experiments sum 87 stress conditions for 18 different nanomaterials (NMs). ACE expression following TiO2 NM exposure was clearly different from other NMs showing a clear (6-7 fold) ACE down-regulation, not observed for any other NMs. Other NMs, notably Ag NMs, and to some extent Cu NMs, caused ACE up-regulation (up to 4 fold). The extensive knowledge from response to NMs can support the immuno-research community, especially to develop therapies for virus that trigger the innate immune system.
... Though the SARS-CoV-2 diameter has been reported within 60−150 nm (Kim et al., 2020;Park et al., 2019;Ren et al., 2020;Zhu et al., 2020), respiratory viruses are emitted from the respiratory tracts attached to droplets in the respiratory secretions during respiratory activities. Particles generated by respiratory activities range from 10 nm to 500 µm (Gralton et al., 2011). ...
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The influence of the number of wash cycles, the wash temperature and the use of detergent was evaluated on the performance of one medical face masks (MFM) and ten community face masks (CFM). The performance of the new and washed masks was characterized from the bacterial filtration efficiency (BFE) and the differential pressure (DP). The tests on the new masks showed that the MFM had always better BFE than CFMs. Although two of the CFMs showed a BFE value exceeding 95%, only one can be classified as type I MFM based on both BFE and DP requirements. The influence of the washing parameters was investigated on the MFM and these two CMFs with excellent BFE properties. The parameters had no effect on the BFE of CFMs whilst the MFM exhibited a loss in efficiency when washed with detergent as a result of the loss of electrostatic charges on the meltblown layer. The DP of masks were not impacted by the washing. The results clearly show that even though a compromise has to be made between the BFE and breathability, it seems possible to manufacture CFMs with performances similar to a type I MFM, without being able to achieve type II requirements.
... The size of the SARS-CoV-2 virion varies between 70 and 90 nm [25,26], and a mean virus concentration in sputum of 7.0 × 10 6 copies/mL and a maximum of 2.4 × 10 9 copies/mL has been reported [27]. Consequently, the viral load occupies 2.1 × 10 −6 % of the bioaerosol on average. ...
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Article
The spread dynamics of the SARS-CoV-2 virus have not yet been fully understood after two years of the pandemic. The virus’s global spread represented a unique scenario for advancing infectious disease research. Consequently, mechanistic epidemiological theories were quickly dismissed, and more attention was paid to other approaches that considered heterogeneity in the spread. One of the most critical advances in aerial pathogens transmission was the global acceptance of the airborne model, where the airway is presented as the epicenter of the spread of the disease. Although the aerodynamics and persistence of the SARS-CoV-2 virus in the air have been extensively studied, the actual probability of contagion is still unknown. In this work, the individual heterogeneity in the transmission of 22 patients infected with COVID-19 was analyzed by close contact (cough samples) and air (environmental samples). Viral RNA was detected in 2/19 cough samples from patient subgroups, with a mean Ct (Cycle Threshold in Quantitative Polymerase Chain Reaction analysis) of 25.7 ± 7.0. Nevertheless, viral RNA was only detected in air samples from 1/8 patients, with an average Ct of 25.0 ± 4.0. Viral load in cough samples ranged from 7.3 × 105 to 8.7 × 108 copies/mL among patients, while concentrations between 1.1–4.8 copies/m3 were found in air, consistent with other reports in the literature. In patients undergoing follow-up, no viral load was found (neither in coughs nor in the air) after the third day of symptoms, which could help define quarantine periods in infected individuals. In addition, it was found that the patient’s Ct should not be considered an indicator of infectiousness, since it could not be correlated with the viral load disseminated. The results of this work are in line with proposed hypotheses of superspreaders, which can attribute part of the heterogeneity of the spread to the oversized emission of a small percentage of infected people.
... The coronavirus disease 2019 (COVID-19) pandemic, caused by SARS-CoV-2, was officially classified as a pandemic by the World Health Organization (WHO) in March of 2020, as the number of cases drastically escalated worldwide [5]. Upon successful isolation of the virus from infected patients [6][7][8][9], this novel zoonotic coronavirus was identified as belonging to the Coronaviridae family [10]. SARS-CoV-2 is an enveloped virus and contains a positive-strand RNA genome~30 kb in size. ...
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Article
The ongoing coronavirus disease 2019 (COVID-19) pandemic continues to disrupt essential health services in 90 percent of countries today. The spike (S) protein found on the surface of the causative agent, the SARS-CoV-2 virus, has been the prime target for current vaccine research since antibodies directed against the S protein were found to neutralize the virus. However, as new variants emerge, mutations within the spike protein have given rise to potential immune evasion of the response generated by the current generation of SARS-CoV-2 vaccines. In this study, a modified, HexaPro S protein subunit vaccine, delivered using a needle-free high-density microarray patch (HD-MAP), was investigated for its immunogenicity and virus-neutralizing abilities. Mice given two doses of the vaccine candidate generated potent antibody responses capable of neutralizing the parental SARS-CoV-2 virus as well as the variants of concern, Alpha and Delta. These results demonstrate that this alternative vaccination strategy has the potential to mitigate the effect of emerging viral variants.
... The cytopathic effect of viral infection is defined as pathological and morphological changes in cells caused by viruses, including SARS-CoV-2 8,9 . However, it has been observed that the cytopathic effect of SARS-CoV-2 occurs only in specific cell lines 10 . ...
Article
Several receptors for the angiotensin-converting enzyme 2 (ACE2), essential for the penetration of SARS-CoV-2 into cells, are located in the tissues of the endocrine glands. Therefore, it has been suggested that SARS-CoV-2 infection results in the development of hormonal disturbances. To date, several cases of endocrine disturbances related to the dysfunction of all endocrine glands during and after SARS-CoV-2 infection have been described. In this review, we discuss the endocrine system disturbances in patients with COVID-19 and post-COVID-19 syndrome. Based on the case reports described in the literature, patients with COVID-19 may develop endocrine disturbances that are immediately life-threatening. In addition, patients with post-COVID-19 syndrome may develop chronic endocrine disturbances. In summary, the diagnostics of endocrine system disturbances based on clinical symptoms should be taken into account in both patients with COVID-19 and post-COVID-19 syndrome.
... Neutralization assays based on cytopathic effect (CPE) were performed as previously described [13]. Briefly, 50 μL serum samples diluted from 2-to 4,096-fold were added to 50 μL of cell culture medium containing 50 times the tissue culture infective dose of the WT virus without the D614G mutation (BetaCoV/Korea/SNU01/2020) [14] or the Delta variant virus (isolated from SNUH, GenBank accession no.MZ853946) in each of a 96-well plate, and the plates were incubated at 37 °C for 2 h in CO2 5% vol/vol. Virus antibody mix was added to these wells, and the plates were incubated at 37°C for 5 days. ...
Article
Background: Humoral immunity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may wane rapidly in persons recovered from mild coronavirus disease 2019 (COVID-19), but little is known about the longevity. Methods: Serum samples were obtained 8, 12, and 18 months after infection from 20 patients with mild COVID-19. The binding activities of serum antibodies (IgA, IgG, and IgM) against SARS-CoV-2 antigens of the Wuhan-1 reference strain (wild-type) and the B.1.1.7, P.1, B.1.167.2, and B.1.1.529 variants were measured by enzyme-linked immunosorbent assays. Neutralizing antibody titers were measured using a cytopathic effect-based live virus neutralization assay. Results: Serum IgA and IgG antibodies against spike or receptor-binding domain (RBD) protein of wild-type SARS-CoV-2 were detected for up to 18 months, and neutralizing antibodies persisted for 8 to 18 months after infection. However, any significant antibody responses against RBD proteins of SARS-CoV-2 variants were not observed, and median neutralizing antibody titers against the Delta variant at 8, 12, and 18 months were 8-11 fold lower than against wild-type viruses (P < .001). Conclusions: Humoral immunity persisted for up to 18 months after SARS-CoV-2 infection in patients with mild COVID-19. Humoral immune activity against more recently circulating variants, however, was reduced in this population.
... SARS-CoV-2, as a cell-cytotoxic virus, during part of its replication cycle, leads to the death and damage of cells and tissues infected [20]. As seen in SARS-CoV patients [21], infection and proliferation of the virus in epithelial cells of the airway system can increase virus-associated pyroptosis accompanied by vascular leakage [22]. ...
Article
Severe Acute Respiratory Syndrome-Coronavirus 2 (SARS-CoV-2) that causes COVID-19 disease could progress to Acute Respiratory Distress Syndrome (ARDS). The immune cells’ migration in response to the virus leads to cell death by releasing oxidizing free radicals. These oxidizing free radicals mediate NF-κB (Nuclear Factor ‘kappa-light-chain-enhancer’ of activated B-cells) activation and induce transcription of cytokine-producing genes that eventually causes cytokine storm and septic shock. The over-expression of oxidative stress and enhancing Reactive Oxygen Species (ROS) and Reactive Nitrogen Species (RNS) production activate transcription factors like NF-κB. So repeating this cycle intensifies the host’s inflammatory responses. In this way, antioxidants as compounds that inhibit oxidation by terminating chain reactions are suggested to alleviate COVID-19 symptoms. In the present review study, the pathogenesis of the virus, the virus immunopathology, and the balance between immune responses and oxidative stress are discussed. Also, in this review, due to the importance of oxidative stress in the pathogenesis of the disease, some of the most important antioxidant agents whose therapeutic effects have been shown in improving many viral infections, ARDS, and acute lung injury, are recommended to improve the patient’s condition infected with SARS-CoV-2. Besides, the recent COVID-19 clinical studies in this field are summarized in this review article. In the present review study, the pathogenesis of the virus, the virus immunopathology, and the balance between immune responses and oxidative stress are discussed. Also, in this review, due to the importance of oxidative stress in the pathogenesis of the disease, some of the most important antioxidant agents whose therapeutic effects have been shown in improving many viral infections, ARDS, and acute lung injury, are recommended to improve the patient’s condition infected with SARS-CoV-2. Besides, the recent COVID-19 clinical studies in this field are summarized in this review article. According to these studies, melatonin through promoting sleep quality, decreasing vascular permeability, reducing anxiety, and regulating blood pressure; vitamin C through decreasing the mortality rates and the requirement for mechanical ventilation; glutathione through decreasing respiratory distress in the pneumonia of COVID-19 patients; and high selenium levels could improve the COVID-19 patients’ clinical outcomes.
... Blind passage to new monolayer Vero cell culture was performed three days after inoculation by injecting 1 mL supernatant media from infected cells, followed by a one-hour incubation before adding 4 mL of fresh MEM supplemented with 10% FBS medium. The cytopathogenic effect (CPE) and plaque-forming unit (PFU) assays were used to evaluate viral growth (Park et al., 2020). ...
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Article
Context: The SARS-CoV-2 virus is the cause of the COVID-19 pandemic, which is a severe public health crisis worldwide.Aims: To analyze the SARS-CoV-2 isolates of Surabaya and predict ORF1ab polyprotein epitopes through the bioinformatics approach for vaccine candidate development. Methods: Three genomic sequences of Surabaya isolates were obtained from the GISAID, NCBI and PDB Gen-bank databases and MEGA-11 software were used to understand the transformations in the isolates. The IEDB and VaxiJen, AllerTop, and ToxinPred web servers were used to predict B-cell epitopes and analyze their antigenicity, non-allergenicity, non-toxicity, respectively. Moreover, these epitopes were linked by EAAAK for 3D modeling, refinement, and validation through Swiss-Model, Galaxy Refine, and RAMPAGE web tools. Results: The Surabaya isolates, RSDS-RCVTD-UNAIR-49-A, 54-A, and 42-A, had 10, 20, and 16 mutations in nucleotides and depicted a phylogenetically close relationship to isolates of Egypt, Pakistan, and Bangladesh, respectively. A total of 71 sequential Orf1ab B-cell epitopes were predicted, and only three peptides were found to be antigenic, non-allergenic, and non-toxic. These epitopes were linked with the EAAAK linker to develop a 3D refined and validated structure. This construct was docked with TLR-3 receptor by the Cluspro webserver and found a high affinity of ORF1ab+TLR3 due to 15 hydrogen bonds. The construct demonstrated good humoral and cellular immune responses in the C-ImmSim server, and cloning in the expression vector pET28a (+) yielded a colon of 846bp. Conclusions: ORF1ab B-cell epitopes could be useful for developing effective vaccines to combat SARS-CoV-2 infection.
... SARS-CoV-2 was first described in December 2019 in Wuhan/China [17] and rapidly spread over many countries, including Thailand, Japan, Korea, Vietnam, Singapore [8,10,14,16] and Italy [11], until it reached Austria not even three months later. ...
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Article
Since its outbreak in 2019, Severe Acute Respiratory Syndrome Coronavirus 2 keeps surprising the medical community by evolving diverse immune escape mutations in a rapid and effective manner. To gain deeper insight into mutation frequency and dynamics, we isolated ten ancestral strains of SARS-CoV-2 and performed consecutive serial incubation in ten replications in a suitable and common cell line and subsequently analysed them using RT-qPCR and whole genome sequencing. Along those lines we hoped to gain fundamental insights into the evolutionary capacity of SARS-CoV-2 in vitro. Our results identified a series of adaptive genetic changes, ranging from unique convergent substitutional mutations and hitherto undescribed insertions. The region coding for spike proved to be a mutational hotspot, evolving a number of mutational changes including the already known substitutions at positions S:484 and S:501. We discuss the evolution of all specific adaptations as well as possible reasons for the seemingly inhomogeneous potential of SARS-CoV-2 in the adaptation to cell culture. The combination of serial passage in vitro with whole genome sequencing uncovers the immense mutational potential of some SARS-CoV-2 strains. The observed genetic changes of SARS-CoV-2 in vitro could not be explained solely by selectively neutral mutations but possibly resulted from the action of directional selection accumulating favourable genetic changes in the evolving variants, along the path of increasing potency of the strain. Competition among a high number of quasi-species in the SARS-CoV-2 in vitro population gene pool may reinforce directional selection and boost the speed of evolutionary change.
... Next, we examined the antiviral efficacy of TFQ on the viral production and infection rates of SARS-CoV-2. Vero E6 cells, which are kidney epithelial cells isolated from an African green monkey and commonly used to produce SARS-CoV-2 [36,50] were infected with SARS-CoV-2 [51,52]. Vero E6 cells are susceptible to SARS-CoV-2 infection, which induces CPE [53]. ...
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Article
The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has severely affected human lives around the world as well as the global economy. Therefore, effective treatments against COVID-19 are urgently needed. Here, we screened a library containing Food and Drug Administration (FDA)-approved compounds to identify drugs that could target the SARS-CoV-2 main protease (Mpro), which is indispensable for viral protein maturation and regard as an important therapeutic target. We identified anti-malarial drug tafenoquine (TFQ), which is approved for radical cure of Plasmodium vivax and malaria prophylaxis, as a top candidate to inhibit Mpro protease activity. The crystal structure of SARS-CoV-2 Mpro in complex with TFQ revealed that TFQ noncovalently bound to and reshaped the substrate binding pocket of Mpro by altering the loop region (residues 139-144) near the catalytic Cys145, which could block the catalysis of its peptide substrates. We also found that TFQ inhibited human transmembrane protease serine 2 (TMPRSS2). Furthermore, one TFQ derivative, compound 7, showed a better therapeutic index than TFQ on TMPRSS2, and may therefore inhibit the infectibility of SARS-CoV-2, including that of several mutant variants. These results suggest new potential strategies to block infection of SARS-CoV-2 and rising variants.
... SARS-CoV-2 particles attached to the cell surfaces with an average diameter of 76 nanometers and with spherical morphology exhibiting spikes on their envelope, which is characteristic of viruses belonging to the Coronaviridae family. This data is very consistent with previous in vitro studies of SARS-CoV [9] and SARS-CoV-2 in which the virion diameter ranged from 60 to 140 nm [14,38,[40][41][42]. ...
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Article
The pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has impacted public health and the world economy and fueled a worldwide race to approve therapeutic and prophylactic agents, but so far there are no specific antiviral drugs. Understanding the biology of the virus is the first step in structuring strategies to combat it, and in this context several studies have been conducted with the aim of understanding the replication mechanism of SARS-CoV-2 in vitro systems. In this work, studies using transmission and scanning electron microscopy and 3D electron microscopy modeling were performed with the goal of characterizing the morphogenesis of SARS-CoV-2 in Vero-E6 cells. Several ultrastructural changes were observed—such as syncytia formation, cytoplasmic membrane projections, lipid droplets accumulation, proliferation of double-membrane vesicles derived from the rough endoplasmic reticulum, and alteration of mitochondria. The entry of the virus into cells occurred through endocytosis. Viral particles were observed attached to the cell membrane and in various cellular compartments, and extrusion of viral progeny took place by exocytosis. These findings allow us to infer that Vero-E6 cells are highly susceptible to SARS-CoV-2 infection as described in the literature and their replication cycle is similar to that described with SARS-CoV and MERS-CoV in vitro models.
... The BFE method was modified, and Staphylococcus aureus (S. aureus) was replaced by nano-bacteria (the hypothesized nano-bacteria are mostly 0.05 to 0.2 mm in size) as the test specimen [41], which is roughly similar to the SARS-CoV-2 diameter [42]. This precautionary change was applied to this experiment, so that the chosen nano-bacteria can represent SAR-CoV-2 [21]. ...
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Article
Membrane materials might be used for face protection because they can decontaminate the inhaled air from particle pollution and viruses like the SARS-Cov0-2 which damages our respiration system. In this study, plyethersulfone membranes (PES) were synthesized with green solvent at room temperature and its filtration effectiveness was investigated against nano-bacteria (size 0.05 to 0.2 µm) by measuring their Bacterial Filtration Efficiency (BFE) and micro aerosol size (0.3 µm), and Particulate Filtration Efficiency (PFE). The average SARS-CoV-2 diameters are between 50 nm to 160 nm. A series of experiments were performed to accomplish between 0.03 to 0.21 µm PES sponge like diameters so that can be used for SARS-CoV-2 filtration. Results showed that nanofiltration/ultrafiltration could filter 99.9% of bacteria and aerosol from contaminated air the size of the Covid-19 molecule.
... coronaviruse/ situation-reports/20200423-sitrep-94-covid-19.pdf?sfvrsn =b8304bf0_4). The virus is small in size ranging in diameter between 66-81nm (Park et al., 2019). The World Health Organization has (WHO) designated the coronavirus disease caused by the virus as COVID-19. ...
Article
Coronavirus disease (COVID-19) pandemic has recently become a global health crisis. On the basis of this study the data reported from ten different countries on confirmed daily deaths caused by COVID-19. By fitting the linear regression models based on the data from ten countries to find the relationship between the new cases and deaths reported daily. We also used the autoregressive integrated moving average model (ARIMA) to predict the potential number of daily deaths caused by COVID-19 in these countries in the next 3 Months. The R2value obtained for Iran (0.24) implies that 24% of daily deaths correspond to the daily cases. The R2of Pakistan 0.662 which indicates that 66.2% of daily deaths are explained by our predictor variable. In Turkey 70.2% of daily deaths are explained by daily cases and India recorded the highest number of deaths while UAE had the lowest number of deaths. Our results suggest that the pandemic is under control in China, UAE and Australia. Pakistan, Iran, Germany and Italy however, showed an upward trend in the spread of the disease, which may correlate with a high increase in death rate as the data indicated.
... 6 The JKMS issues are now published every Monday, enabling rapid dissemination of cutting-edge knowledge in medicine and public health. All COVID-19 submissions have been separately handled in line 12 with an urgently designed fast-track processing, editing, and publishing strategy. Such strategy coupled with advanced global visibility positions the JKMS among the best target journals amidst the ongoing COVID-19 pandemic. ...
Article
During the coronavirus disease 2019 (COVID-19) pandemic, publications on the disease have exploded globally. The present study analyzed PubMed and KoreaMed indexed COVID-19 publications by Korean researchers from January 1, 2020 to August 19, 2021. A total of 83,549 COVID-19 articles were recorded in PubMed and 1,875 of these were published by Korean authors in 673 journals (67 Korean and 606 overseas journals). The KoreaMed platform covered 766 articles on COVID-19, including 612 by Korean authors. Among the Journal of Korean Medical Science (JKMS) articles on COVID-19, PubMed covered 176 and KoreaMed 141 documents. Korean researchers contributed to 2.2% of global publications on COVID-19 in PubMed. The JKMS has published most articles on COVID-19 in Korea.
... On the other hand, there are some alternatives that significantly improve the tightness and thus the RPL. The methodology proposed in our study is based on the measurement of the particles that managed to pass through the RPE, unlike the Fit Testing Procedure method, indicated by the Occupational Safety & Health Administration (OSHA) (16) , where a detector is used, based on the condensation principle, which includes the measurement of particles of 0.02 to 0.08 μm, which are unlikely to contain at least one unit of active SARS-CoV-2 virus, whose size has been estimated at 0.08 +/-0.01 μm (17,18) . Despite the limited evidence on the presence of active SARS-CoV-2 and its distribution in particles smaller than 10 µm, the capacity of particles to transport active viruses has been determined to increase with their size, which could be explained by a greater shielding effect of the virus as the size of the droplets increases (19) . ...
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Preprint
Objective: To develop a methodology for evaluating the level of respiratory protection provided by respirators , surgical masks and community face masks used by the Peruvian population; protection was evaluated against particles of a size similar to those containing active SARS-CoV-2 virus. Materials and methods: A direct linear relationship has been determined between the logarithm of the concentration of airborne particles and the elapsed time; thus, it is possible to compare the quantity of particles inside and outside of the mask or respirator in the same time period, as well as to obtain the percentage of respiratory protection for each evaluated sample. Results: A methodology was established to evaluate the level of respiratory protection against aerosols smaller than 5.0 μm. Also, the use of accessories such as rubber bands or adjusters behind the head and neck, and the use of robust nasal clips, significantly increased the level of respiratory protection against particles with a high probability of containing SARS-CoV-2. Conclusions: We found concordance between the obtained respiratory protection values and those expected, considering the filtration level of the material used for each surgical mask or respirator, as well as the tightness. A significant increase in the levels of respiratory protection was observed.
... Finally, the vesicles containing the virus particles fuse with the plasma membrane to release the virus that causes pyroptosis of the host cell-associated with vascular leakage in the airway epithelial cells and tissues. Pyroptosis, a highly inflammatory programmed cell death is commonly seen in the case of cytopathic viral infection as observed in the case of SARS-COV-2 infection [15,16]. ...
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Article
Coronavirus disease 2019 or COVID-19, the unprecedented global pandemic is caused by Severe Acute Respiratory Syndrome Coronavirus 2 or SARS-COV-2 which has a long incubation period, higher transmission rate than other viruses, and it is transmitted through zoonotic modes where bats are found to be the main reservoir for these types of viruses. The innate and adaptive immune system plays a very crucial role in preventing viral infection. But, sometimes, the host’s own immune system is dysregulated causing hyper inflammation and impaired pulmonary gas exchange, severe multi-organ damage and eventually death. In the present review, we have highlighted the “battle of triad”, i.e., interaction among SARS-COV-2, healthy immune system and dysfunctional immune system. The association between dysfunctional immune system and disease severity resulting in hyper-inflammation, cytokine storm and penultimate death of COVID-19 patients may serve as a key factor for developing effective vaccines and other therapeutics against SARS-COV-2. Till now, a number of therapeutic strategies have been developed to combat COVID-19 and in the present review, we have summarized several potential therapeutic strategies such as immunomodulatory drugs, plasma therapy, anti-viral treatments and active immunizations via vaccine development that has been proved to be useful to prevent the severity of this disease. The present review may help to understand the overall perspective of host-pathogen interaction that may resolve the enigma in further therapeutic development to combat the devastating effect of this disease.
... It causes respiratory illnesses to both humans and animals and was not considered harmful to humans until the outbreak of SARS-CoV (Cui et al., 2018). The genome of coronavirus is large, with approximately 30 kb in length (Park et al., 2020). The coronavirus has 6 to 11 open reading frames and encodes 9,680 amino acids polyproteins and lacks hemagglutinin-esterase gene . ...
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Article
COVID-19 is a worldwide epidemic that continues to pose a major health risk to everyone. This study focused on the possible potential of antioxidants in enhancing immunity of individuals against COVID-19 by delineating which antioxidant food supplements has the potential effectiveness against the COVID-19 infection, what mechanisms these antioxidant food supplements possess, and what regulations must be observed for the safe and efficacious administration of food supplements in relation to a person's age and health status. The descriptive study approach was utilized to evaluate the components, features, processes, and effects of several antioxidant food supplements on strengthening the immune system of people who were infected with COVID-19. T-test for unequal variances was employed to observe if there was a significant difference in the suppression of IL-6 and TNF-α between the treatment group and the control group of the gathered studies. As shown, virgin coconut oil, curcumin, selenium, and those supplements incorporating more than three combinations of antioxidants exhibited a great potential effectiveness against the COVID-19 infection. Supporting diverse adaptive and innate immune responses are the primary mechanisms of antioxidant food supplements. Curcumin, selenium, and N-acetylcysteine, in particular, have been found to reduce inflammatory factors connected to the worsened COVID-19 development. The safe and effective use of appropriate supplements may vary according to age and health status.
... SARS-CoV-2 is a spherical, crown-shaped, enveloped, positive-sense single-stranded RNA virus 66-100 nm in diameter with a genome size of~29 kb [18]. For host tropism, the S protein of SARS-CoV-2 binds to cell-surface ACE2 proteins through their receptor-binding domain (RBD). ...
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Article
Currently, the third and fourth waves of the coronavirus disease -19 (COVID-19) pandemic are creating havoc in many parts of the world. Although vaccination programs have been launched in most countries, emerging new strains of the virus along with geographical variations are leading to varying success rates of the available vaccines. The presence of comorbidities such as diabetes, cardiovascular diseases and hypertension is responsible for increasing the severity of COVID-19 and, thus, the COVID-19 mortality rate. Angiotensin-converting enzyme 2 (ACE2), which is utilized by SARS-CoV-2 for entry into host cells, is widely expressed in the lungs, kidneys, testes, gut, adipose tissue, and brain. Infection within host cells mediates RAS overactivation, which leads to a decrease in the ACE2/ACE ratio, AT2R/AT1R ratio, and MasR/AT1R ratio. Such imbalances lead to the development of heightened inflammatory responses, such as cytokine storms, leading to post-COVID-19 complications and mortality. As the association of SARS-CoV-2 infection and hypertension remains unclear, this report provides an overview of the effects of SARS-CoV-2 infection on patients with hypertension. We discuss here the interaction of ACE2 with SARS-CoV-2, focusing on neuronal ACE2 (nACE2), and further shed light on the possible involvement of nACE2 in hypertension. SARS-CoV-2 enters the brain through neuronal ACE2 and spreads in various regions of the brain. The effect of viral binding to neuronal ACE2 in areas of the brain that regulate salt/water balance and blood pressure is also discussed in light of the neural regulation of hypertension in COVID-19.
... SARS-CoV-2 has been the focus of much study in certain fields such as molecular biology by electron microscopy (EM) [5][6][7], which is a powerful tool in the field of microbiology. It has played a key role in the rapid identification of viruses in patient samples and has contributed significantly to the clarification of viral structure and function, which help guide the public health response to emerging viral infections [8]. ...
Article
SARS-CoV-2 is the cause of COVID-19. The three-dimensional morphology of viral particles existing and multiplying in infected cells has not been established by electron tomography, which is different from cryo-electron tomography using frozen samples. In this study, we establish the morphological structure of SARS-CoV-2 particles by three-dimensional reconstruction of images obtained by electron tomography and transmission electron microscopy of biological samples embedded in epoxy resin. The characteristic roots of spike structures were found to be arranged at the surface of a virion covered with an envelope. A high-electron-density structure that appears to be a nucleocapsid was observed inside the envelope of the virion on three-dimensional images reconstructed by electron tomography. The SARS-CoV-2 particles that budded in the vacuoles in the cytoplasm were morphologically identical to those found outside the cells, suggesting that mature and infectious SARS-CoV-2 particles were already produced in the vacuoles. Here, we show the three-dimensional morphological structure of SARS-CoV-2 particles reconstructed by electron tomography. To control infection, inhibition of viral release from vacuoles would be a new target in the development of prophylactic agents against SARS-CoV-2.
... Expiratory particles size emitted during breathing and speech are sufficiently large to carry viable virus, i.e. within 60-140 nm according to several authors Matsuyama et al., 2020;Park et al., 2020;Ren et al., 2020). But they are small enough to be inhaled, penetrate deeper into the respiratory tract and, consequently, have more serious health implications. ...
Article
The tension on the supply of surgical and FFP2 masks during the first wave of the COVID-19 pandemic leads to study the potential reuse of these masks. As washing is easily adaptable at home, this treatment solution was retained. In this work, thirty-six references of surgical masks and four FFP2 masks were tested without being worn or washed and after several washing cycles. The results highlighted a great heterogeneity of performances depending on the mask trademarks, both for surgical masks and FFP2. The quality of the meltblown and spunbond layers and the presence/absence of electrostatic charges at the fiber surface are put forward to explain the variability of results, both on differential pressures and filtration efficiencies. The differential pressure and the particle filtration efficiency of the washed masks were maintained up to 10 washing cycles and met the standard requirements. However, an immersion in water with a detergent induces an efficiency decrease for submicronic particles. This lower performance, constant after the first washing cycle, can be explained by the loss of electrostatic charges during the washing cycle. The modifications of surface properties after washing also lead to a loss of the hydrophobic behavior of type IIR surgical masks, which can therefore no more be considered as resistant to blood projections.
... A constant effort is also being devoted to track the virus spread at the regional, national and global level since the first epidemic outbreak. In February 2020, Park et al. [123] analyzed the first COVID-19 case in Korea using phylogenetic analysis and found that it clustered together with other SARS-CoV-2 sequences reported from Wuhan. Subsequently, by fitting a molecular clock model, Zehender et al. [180] analyzed the viral sequences isolated from three patients in the first outbreak of COVID-19 in Italy and concluded that the virus was present in Italy weeks before the first case was reported in 21 February 2020. ...
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Article
SARS-CoV-2 caused the first severe pandemic of the digital era. Computational approaches have been ubiquitously used in an attempt to timely and effectively cope with the resulting global health crisis. In order to extensively assess such contribution, we collected, categorized and prioritized over 17 000 COVID-19-related research articles including both peer-reviewed and preprint publications that make a relevant use of computational approaches. Using machine learning methods, we identified six broad application areas i.e. Molecular Pharmacology and Biomarkers, Molecular Virology, Epidemiology, Healthcare, Clinical Medicine and Clinical Imaging. We then used our prioritization model as a guidance through an extensive, systematic review of the most relevant studies. We believe that the remarkable contribution provided by computational applications during the ongoing pandemic motivates additional efforts toward their further development and adoption, with the aim of enhancing preparedness and critical response for current and future emergencies.
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Article
The number of confirmed cases of COVID-19 globally is well over 400 million, however, the number of cases is showing a downward trend especially in developed countries largely as a result of effective vaccination against COVID-19. In developing countries, vaccination coverage is still very low as a result of vaccine hesitancy, which could be attributed to misconceptions about COVID-19 itself and its newly developed vaccines. This study assessed COVID-19 vaccine acceptance and perception amongst the adult population in Sokoto state, Nigeria. A cross-sectional study was conducted in Sokoto state among 854 respondents selected via a multi-stage sampling technique. Data was collected electronically using a set of structured questionnaire and analysis was done using IBM SPSS version 25. Respondents’ perception was assessed using a 5-point Likert scale ranging from strongly disagree (1) to strongly agree (5). Respondents having a score of 3 and below were graded as having poor perception and those having scores above 3 were graded as having good perception. Respondents’ ages ranged from 17 to 76 years, with a mean of 34.8±12.07; more than half [474(53.7%)] of the respondents were males, 667(75.5%) were married and 539(61.0%) had formal education. The majority [839(95.0%)] of the respondents had a good perception of COVID -19 vaccine; 49.9% agreed enough research would be required on the safety of the vaccine. The majority, (72.4%) expressed their willingness to accept the COVID- 19 vaccine (male 38.4% vs. female 34.0%); 410(47.4%) said they can spend more than one hour to get the vaccine. Significant predictors of willingness to accept COVID 19 vaccine include age (p = 0.006; aOR = 0.223; 95% CI = 0.077–0.645), education (p
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Introduction The innate immune responses of upper airway could further our understanding toward antiviral strategies against SARS-CoV-2. We characterize the potential of interferon (IFN)-λ as an innate immune inducer for the rapid clearance of SARS-CoV-2 in the lung and the therapeutic efficacy of intranasal inoculation of IFN-λ to resolve acute lung infection. Methods Syrian golden hamsters were infected with SARS-CoV-2 and the dynamics of SARS-CoV-2 infection depending on IFN-λ inoculation were tested. Results SARS-CoV-2-infected Syrian golden hamsters exhibited a significant decrease in body weight and high viral mRNA level at 3 days post-infection (dpi). Although viral replication was reduced completely from 7 dpi, the pathologic findings remained prominent until 14 dpi in the lung of hamsters. The transcription of IFN-λ was significantly induced in response to SARS-CoV-2 infection with the increase of IFN-stimulated genes. Intranasal inoculation of IFN-λ restricted SARS-CoV-2 replication in the lungs of infected completely from 3 dpi with markedly reduction of inflammatory cytokines. The transcriptional phenotypes were altered to the direction of damage repair and tissue remodeling in the lungs of SARS-CoV-2-infected hamsters following intranasal inoculation of IFN-λ, which improved SARS-CoV-2-caused lung damage. Conclusion Collectively, our findings suggest that IFN-λ might be a potent innate immune inducer in the lung and intranasal inoculation of IFN-λ resolves SARS-CoV-2 infection with rapid viral clearance and improvement of lung damage.
Article
Several systems are being developed and investigated for the delivery of COVID-19 vaccines. A crucial challenge is the ability to maintain vaccine efficacy through the use of an effective delivery system. Some of these vaccine delivery systems such as lipid nanoparticles (LNPs) have been approved for the use by regulatory authorities in numerous countries. LNPs are currently used for the delivery of Moderna and Pfizer/BioNtech vaccines. LNPs consist of four constituents: Cholesterol for LNP stabilization, cationic lipids for the protection of messenger RNA (mRNA) molecules from nuclease degradation, and helper phospholipids that aid the formation and intracellular release of mRNA and PEGylated lipids that reduce nonspecific interactions. Researchers have also used virus-like particles (VLPs) for COVID-19 vaccine delivery. VLPs consist of several hollow viral proteins without the viral genome. VLPs are structurally identical to the native virus and can activate the human adaptive immune response. The nanosized VLPs self-assemblies have investigated as potential platforms for the delivery of COVID-19 vaccines. Liposomal vesicles are amphiphilic since the polar headgroups of phospholipids are oriented toward water molecules and the hydrophobic chains are in the internal area of the vesicles. The rationale behind the utilization of liposomes as vaccine delivery systems is their versatility and flexibility. Messenger RNA coding for SARS-CoV-2 spike protein can be entrapped into liposomes that are designed to remain stable in the bloodstream until their uptake by phagocytic cells. Other vaccine delivery approaches such as the use of microneedles and electroporation provide transdermal vaccine transport enable COVID-19 vaccines to cross the skin but not the cells of deep-lying tissues.
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The recent outbreak of COVID-19 rose a new wave of interest to coronaviruses though the first coronaviruses were discovered in the first half of the XX century. That time coronaviruses were considered as a quite serious veterinary problem but they were not believed to become highly dangerous for humans. However, such ideas were revised in 2002 when SARS-CoV was transferred to human population in the Southeast Asia assumably from the bats, and later in 2012 when natural focus of the MERS-CoV was discovered in the Arabian countries. Due to the increased interest a large number of new Coronaviridae family members was revealed in the first decades of the XXI century. Since then taxonomic structures of coronaviruses underwent significant changes. This review is focused on the need for continued monitoring of the biological diversity of coronaviruses. The structural studies of coronaviruses regardless of the host species may allow us to identify early changes that can affect the evolutionary drift process of a particular HCoV species in volved in viral transmission from bats or birds to humans.
Article
Evidence of micro- and macro-thrombi in the arteries and veins of critically ill COVID-19 patients and in autopsies highlight the occurrence of COVID-19-associated coagulopathy (CAC). Clinical findings of critically ill COVID-19 patients point to various mechanisms for CAC; however, the definitive underlying cause is unclear. Multiple factors may contribute to the prothrombotic state in patients with COVID-19. Aberrant expression of tissue factor (TF), an initiator of the extrinsic coagulation pathway, leads to thrombotic complications during injury, inflammation, and infections. Clinical evidence suggests that TF-dependent coagulation activation likely plays a role in CAC. Multiple factors could trigger abnormal TF expression and coagulation activation in patients with severe COVID-19 infection. Proinflammatory cytokines that are highly elevated in COVID-19 (IL-1β, IL-6 and TNF-α) are known induce TF expression on leukocytes (e.g. monocytes, macrophages) and non-immune cells (e.g. endothelium, epithelium) in other conditions. Antiphospholipid antibodies, TF-positive extracellular vesicles, pattern recognition receptor (PRR) pathways and complement activation are all candidate factors that could trigger TF-dependent procoagulant activity. In addition, coagulation factors, such as thrombin, may further potentiate the induction of TF via protease-activated receptors on cells. In this systematic review, with other viral infections, we discuss potential mechanisms and cell-type-specific expressions of TF during SARS-CoV-2 infection and its role in the development of CAC.
Chapter
Viral infectious diseases may cause neurological symptoms primarily in two nonexclusive ways. Infection may lead to an excessive inflammatory response that damages the neuronal system, which is referred to as immunopathology, or the pathogen is able to infect brain cells, such as neurons or nonneuronal glial cells, like oligodendrocytes, microglia, and astrocytes. Viruses that target and infect cells of the CNS, in general, are called neurotropic. 3D brain organoids provide favorable conditions to study target cells and induced pathomechanisms associated with such viral neurotropism. In the context of highly pathogenic viruses, strict safety precautions (safety level-3 laboratory) must be taken if infectious laboratory strains or strains from clinical samples are to be used for infection experiments. Likewise, safe inactivation protocols must be used for subsequent analysis. This chapter will discuss appropriate protocols, focusing on methodological aspects for each of these steps, and discuss advantages and disadvantages when working with 3D brain organoids while handling biosafety level-3 pathogens based on our work with severe acute respiratory virus type 2 (SARS-CoV-2).Key words3D brain organoids SARS-CoV-2 Biosafety level-3 (BSL-3) Neurotropism Viral replicationPathomechanisms
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Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a highly transmissible and virulent human-infecting coronavirus that emerged in late December 2019 in Wuhan, China, causing a respiratory disease called coronavirus disease 2019 (COVID-19), which has massively impacted global public health and caused widespread disruption to daily life. The crisis caused by COVID-19 has mobilized scientists and public health authorities across the world to rapidly improve our knowledge about this devastating disease, shedding light on its management and control, and spawned the development of new countermeasures. Here we provide an overview of the state of the art of knowledge gained in the last 2 years about the virus and COVID-19, including its origin and natural reservoir hosts, viral etiology, epidemiology, modes of transmission, clinical manifestations, pathophysiology, diagnosis, treatment, prevention, emerging variants, and vaccines, highlighting important differences from previously known highly pathogenic coronaviruses. We also discuss selected key discoveries from each topic and underline the gaps of knowledge for future investigations.
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COVID-19 was declared by WHO as a pandemic since March 2020. The vaccination program has been implemented worldwide. Specific antiviral drugs such as remdesivir, molnupiravir and ritonavir-based nirmatrelvir were effective against SARS-CoV-2 infection. However, the new SARS-CoV-2 variants have been elevated due to viral mutation causing vaccine resistance and rapid spreading. Long-term COVID-19 complications have been life-threatening in some recovery cases. To overcome viral adaptation, cell culture model is essential to comprehend SARS-CoV-2 infection, pathophysiology, complications, and drug target alterations. The classical 2D culture cell was frequency used for viral propagation and high-throughput screening. Modern 3D culture has recapitulated key cellular and molecular events of tissue physiology. Here, we reviewed the cell lines, 3D culture, organoid and relevant models for the aforementioned applications.
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In transmission electron microscopy (TEM), electrons are transmitted through a plastic-embedded specimen, and an image is formed. TEM enables the resolution and visualization of detail not apparent via light microscopy, even when combined with immunohistochemical analysis. Ultrastructural examination of tissues, cells and microorganisms plays a vital role in diagnostic pathology and biologic research. TEM is used to study the morphology of cells and their organelles, and in the identification and characterization of viruses, bacteria, protozoa and fungi. In this protocol, we present a TEM method for preparing specimens obtained in clinical or research settings, discussing the particular requirements for tissue and cell preparation and analysis, the need for rapid fixation and the possibility of analysis of tissue already fixed in formalin or processed into paraffin blocks. Details of fixation, embedding and how to prepare thin and semi-thin sections, which can be used for analysis complementary to that performed ultimately using TEM, are also described.
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In December 2019, a viral pneumonia outbreak caused by a novel betacoronavirus, the 2019 novel coronavirus (2019-nCoV), began in Wuhan, China. We report the epidemiological and clinical features of the first patient with 2019-nCoV pneumonia imported into Korea from Wuhan. This report suggests that in the early phase of 2019-nCoV pneumonia, chest radiography would miss patients with pneumonia and highlights taking travel history is of paramount importance for early detection and isolation of 2019-nCoV cases.
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Most existing methods for DNA sequence analysis rely on accurate sequences or genotypes. However, in applications of the next-generation sequencing (NGS), accurate genotypes may not be easily obtained (e.g. multi-sample low-coverage sequencing or somatic mutation discovery). These applications press for the development of new methods for analyzing sequence data with uncertainty. We present a statistical framework for calling SNPs, discovering somatic mutations, inferring population genetical parameters and performing association tests directly based on sequencing data without explicit genotyping or linkage-based imputation. On real data, we demonstrate that our method achieves comparable accuracy to alternative methods for estimating site allele count, for inferring allele frequency spectrum and for association mapping. We also highlight the necessity of using symmetric datasets for finding somatic mutations and confirm that for discovering rare events, mismapping is frequently the leading source of errors. http://samtools.sourceforge.net. hengli@broadinstitute.org.
A novel coronavirus from patients with pneumonia in China
  • N Zhu
  • D Zhang
  • W Wang
  • X Li
  • Yang B Song
Zhu N, Zhang D, Wang W, Li X, Yang B, Song J, et al. A novel coronavirus from patients with pneumonia in China, 2019. N Engl J Med 2020. DOI: 10.1056/NEJMoa2001017.