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1.
Braz. j. biol ; 83: e247237, 2023. tab, graf
Artigo em Inglês | LILACS-Express | MEDLINE, LILACSEXPRESS | ID: biblio-1339386

RESUMO

Abstract Novel coronavirus (nCoV) namely "SARS-CoV-2" is being found responsible for current PANDEMIC commenced from Wuhan (China) since December 2019 and has been described with epidemiological linkage to China in about 221 countries and territories until now. In this study we have characterized the genetic lineage of SARS-CoV-2 and report the recombination within the genus and subgenus of coronaviruses. Phylogenetic relationship of thirty nine coronaviruses belonging to its four genera and five subgenera was analyzed by using the Neighbor-joining method using MEGA 6.0. Phylogenetic trees of full length genome, various proteins (spike, envelope, membrane and nucleocapsid) nucleotide sequences were constructed separately. Putative recombination was probed via RDP4. Our analysis describes that the "SARS-CoV-2" although shows great similarity to Bat-SARS-CoVs sequences through whole genome (giving sequence similarity 89%), exhibits conflicting grouping with the Bat-SARS-like coronavirus sequences (MG772933 and MG772934). Furthermore, seven recombination events were observed in SARS-CoV-2 (NC_045512) by RDP4. But not a single recombination event fulfills the high level of certainty. Recombination mostly housed in spike protein genes than rest of the genome indicating breakpoint cluster arises beyond the 95% and 99% breakpoint density intervals. Genetic similarity levels observed among "SARS-CoV-2" and Bat-SARS-CoVs advocated that the latter did not exhibit the specific variant that cause outbreak in humans, proposing a suggestion that "SARS-CoV-2" has originated possibly from bats. These genomic features and their probable association with virus characteristics along with virulence in humans require further consideration.


Resumo O novo coronavírus (nCoV), nomeadamente "SARS-CoV-2", foi considerado responsável pela pandemia atual iniciada em Wuhan (China) desde dezembro de 2019 e foi descrito com ligação epidemiológica à China em cerca de 221 países e territórios até agora. Neste estudo, caracterizamos a linhagem genética do SARS-CoV-2 e relatamos a recombinação dentro do gênero e subgênero dos coronavírus. A relação filogenética de 39 coronavírus pertencentes a seus quatro gêneros e cinco subgêneros foi analisada usando o método de Neighbour-joining usando MEGA 6.0. Árvores filogenéticas do genoma de comprimento total, várias proteínas (espícula, envelope, membrana e nucleocapsídeo), sequências de nucleotídeos foram construídas separadamente. A recombinação putativa foi testada via RDP4. Nossa análise descreve que o "SARS-CoV-2", embora mostre grande semelhança com as sequências de Bat-SARS-CoVs em todo o genoma (dando semelhança de sequência de 89%), exibe agrupamento conflitante com as sequências de coronavírus do tipo Bat-SARS (MG772933 e MG772934) Além disso, sete eventos de recombinação foram observados em SARS-CoV-2 (NC045512) por RDP4. Mas nem um único evento de recombinação preenche o alto nível de certeza. A recombinação está alojada mais em genes de proteína de pico, principalmente, do que no resto do genoma, indicando que o cluster de ponto de interrupção surge além dos intervalos de densidade de ponto de interrupção de 95% e 99%. Os níveis de similaridade genética observados entre "SARS-CoV-2" e Bat-SARS-CoVs defendem que o último não exibe a variante específica que causa surto em humanos, sugerindo que "SARS-CoV-2" tenha se originado possivelmente de morcegos. Essas características genômicas e sua provável associação com as características do vírus, juntamente com a virulência em humanos, requerem uma consideração mais aprofundada.

2.
PLoS One ; 17(1): e0260897, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34995294

RESUMO

BACKGROUND: Coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), can manifest with varying disease severity and mortality. Genetic predisposition influences the clinical course of infectious diseases. We investigated whether genetic polymorphisms in candidate genes ACE2, TIRAP, and factor X are associated with clinical outcomes in COVID-19. METHODS: We conducted a single-centre retrospective cohort study. All patients who visited the emergency department with SARS-CoV-2 infection proven by polymerase chain reaction were included. Single nucleotide polymorphisms in ACE2 (rs2285666), TIRAP (rs8177374) and factor X (rs3211783) were assessed. The outcomes were mortality, respiratory failure and venous thromboembolism. Respiratory failure was defined as the necessity of >5 litres/minute oxygen, high flow nasal oxygen suppletion or mechanical ventilation. RESULTS: Between March and April 2020, 116 patients (35% female, median age 65 [inter quartile range 55-75] years) were included and treated according to the then applicable guidelines. Sixteen patients (14%) died, 44 patients (38%) had respiratory failure of whom 23 required endotracheal intubation for mechanical ventilation, and 20 patients (17%) developed venous thromboembolism. The percentage of TIRAP polymorphism carriers in the survivor group was 28% as compared to 0% in the non-survivor group (p = 0.01, Bonferroni corrected p = 0.02). Genotype distribution of ACE2 and factor X did not differ between survivors and non-survivors. CONCLUSION: This study shows that carriage of TIRAP polymorphism rs8177374 could be associated with a significantly lower mortality in COVID-19. This TIRAP polymorphism may be an important predictor in the outcome of COVID-19.

3.
PLoS One ; 17(1): e0261479, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34995312

RESUMO

INTRODUCTION: The Australian National COVID-19 Clinical Evidence Taskforce is producing living, evidence-based, national guidelines for treatment of people with COVID-19 which are updated each week. To continually improve the process and outputs of the Taskforce, and inform future living guideline development, we undertook a concurrent process evaluation examining Taskforce activities and experience of team members and stakeholders during the first 5 months of the project. METHODS: The mixed-methods process evaluation consisted of activity and progress audits, an online survey of all Taskforce participants; and semi-structured interviews with key contributors. Data were collected through five, prospective 4-weekly timepoints (beginning first week of May 2020) and three, fortnightly retrospective timepoints (March 23, April 6 and 20). We collected and analysed quantitative and qualitative data. RESULTS: An updated version of the guidelines was successfully published every week during the process evaluation. The Taskforce formed in March 2020, with a nominal start date of March 23. The first version of the guideline was published two weeks later and included 10 recommendations. By August 24, in the final round of the process evaluation, the team of 11 staff, working with seven guideline panels and over 200 health decision-makers, had developed 66 recommendations addressing 58 topics. The Taskforce website had received over 200,000 page views. Satisfaction with the work of the Taskforce remained very high (>90% extremely or somewhat satisfied) throughout. Several key strengths, challenges and methods questions for the work of the Taskforce were identified. CONCLUSIONS: In just over 5 months of activity, the National COVID-19 Clinical Evidence Taskforce published 20 weekly updates to the evidence-based national treatment guidelines for COVID-19. This process evaluation identified several factors that enabled this achievement (e.g. an extant skill base in evidence review and convening), along with challenges that needed to be overcome (e.g. managing workloads, structure and governance) and methods questions (pace of updating, and thresholds for inclusion of evidence) which may be useful considerations for other living guidelines projects. An impact evaluation is also being conducted separately to examine awareness, acceptance and use of the guidelines.

4.
PLoS One ; 17(1): e0261851, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34995317

RESUMO

Perceived risk clearly impacts travel behavior, including destination selection and satisfaction, but it is unclear how or why its effect is only significant in certain cases. This is because existing studies have undervalued the mediating factors of risk aversion, government initiatives, and media influence as well as the multiple forms or dimensions of risk that can mask its direct effect. This study constructs a structural equation model of perceived risk's impact on destination image and travel intention for a more nuanced model of the perceived risk mechanism in tourism, based on 413 e-questionnaires regarding travel to Chengdu, China during the COVID-19 pandemic, using the Bootstrap method to analyze suppressing effect. It finds that while perceived risk has a significant negative impact on destination image and travel intention, this is complexly mediated so as to appear insignificant. Furthermore, different mediating factors and dimensions of perceived risk operate differently according to their varied combinations in actual circumstances. This study is significant because it provides a theoretical interpretation of tourism risk, elucidates the mechanisms or paths by which perceived risk affects travel intention, and expands a framework for research on destination image and travel intention into the realms of psychology, political, and communication science. It additionally encourages people to pay greater attention to the negative impact of crises and focuses on the important role of internal and external responses in crisis management, which can help improve the effectiveness of crisis management and promote the sustainable development of the tourism industry.

5.
Lancet Public Health ; 7(1): e36-e47, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34995541

RESUMO

BACKGROUND: The COVID-19 pandemic has affected sexual and reproductive health (SRH) service use and unmet need, but the impact is unknown. We aimed to determine the proportion of participants reporting sexual risk behaviours, SRH service use and unmet need, and to assess remote sexually transmitted infection (STI) testing service use after the first national lockdown in Britain. METHODS: We used data from the National Surveys of Sexual Attitudes and Lifestyles (Natsal)-COVID cross-sectional, quasi-representative web survey (Natsal-COVID Wave 1). Adults aged 18-59 years who resided in England, Scotland, or Wales completed the survey between July 29 and Aug 10, 2020, which included questions about the approximate 4-month period after announcement of the initial lockdown in Britain (March 23, 2020). Quota-based sampling and weighting were used to achieve a quasi-representative population sample. Participants aged 45-59 years were excluded from services analysis due to low rates of SRH service use. Among individuals aged 18-44 years, we estimated reported SRH service use and inability to access, and calculated age-adjusted odds ratios (aORs) among sexually experienced individuals (those reporting any sexual partner in their lifetime) and sexually active individuals (those reporting any sexual partner in the past year). Unweighted denominators and weighted estimates are presented hereafter. FINDINGS: 6654 individuals had complete interviews and were included in the analysis. Among 3758 participants aged 18-44 years, 82·0% reported being sexually experienced, and 73·7% reported being sexually active. 20·8% of sexually experienced participants aged 18-44 years reported using SRH services in the 4-month period. Overall, 9·7% of 3108 participants (9·5% of men; 9·9% of women) reported being unable to use a service they needed, although of the participants who reported trying but not being able to use a SRH service at least once, 76·4% of participants also reported an instance of successful use. 5·9% of 1221 sexually active men and 3·6% of 1560 sexually active women reported use of STI-related services and 14·8% of 1728 sexually experienced women reported use of contraceptive services, with SRH service use highest among individuals aged 18-24 years. Sexually active participants reporting condomless sex with new partners since lockdown were much more likely to report using STI-related services than those who did not report condomless sex (aOR 23·8 [95% CI 11·6-48·9]) for men, 10·5 [3·9-28·2] for women) and, among men, were also more likely to have an unsuccessful attempt at STI-service use (aOR 13·3 [5·3-32·9]). Among 106 individuals who reported using STI testing services, 64·4% accessed services remotely (telephone, video, or online). Among 2581 women aged 25-59 years, 2·4% reported cervical screening compared with an estimated 6% in a comparable 4-month period before the pandemic. INTERPRETATION: Many people accessed SRH care during the initial lockdown; however, young people and those reporting sexual risk behaviours reported difficulties in accessing services and thus such services might need to address a backlog of need. FUNDING: Wellcome Trust, The Economic and Social Research Council, The National Institute for Health Research, Medical Research Council/Chief Scientist Office and Public Health Sciences Unit, and UCL Coronavirus Response Fund.

6.
Biomed Pharmacother ; 147: 112614, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34995938

RESUMO

Post-Covid pulmonary fibrosis is evident following severe COVID-19. There is an urgent need to identify the cellular and pathophysiological characteristics of chronic lung squeals of Covid-19 for the development of future preventive and/or therapeutic interventions. Tissue-resident memory T (TRM) cells can mediate local immune protection against infections and cancer. Less beneficially, lung TRM cells cause chronic airway inflammation and fibrosis by stimulating pathologic inflammation. The effects of Janus kinase (JAK), an inducer pathway of cytokine storm, inhibition on acute Covid-19 cases have been previously evaluated. Here, we propose that Tofacitinib by targeting the CD8+ TRM cells could be a potential candidate for the treatment of chronic lung diseases induced by acute SARS-CoV-2 infection.

7.
J Autoimmun ; 127: 102792, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34995958

RESUMO

The emergence and rapid global spread of the new Delta and, more recently, Omicron variants of SARS-CoV-2 pose a daunting public health emergency. Being an RNA virus, the Covid-19 virus is continuing to mutate, resulting in the emergence of new variants with high transmissibility, such as the recently discovered Omicron variant. In this paper, we consider the conditions that may facilitate viral mutations and the emergence of variants with the ability to evade immunity. Here, we have discussed the importance of vaccination with the currently available vaccines. These vaccines are highly effective at preventing serious disease, hospitalization, and death from Covid-19. However, the antibody response induced by these vaccines is short-lasting and there are reports of breakthrough infections. A stable and persistent interaction between T follicular helper cells and germinal center B cells is needed for robust B cell memory response. We discussed the potential reasons behind the breakthrough infections and underscored the importance of developing better second-generation vaccines that may not necessitate frequent booster immunizations and are preventive in nature. This may involve the development of multivalent vaccines and creating vaccines against other viral proteins including conserved proteins. Vaccine hesitancy remains a notable hurdle for implementing vaccination. Furthermore, we recommend different approaches to increase vaccine acceptance, which is a critical translational component of a successful vaccine strategy. These perspectives on overcoming the pandemic's current challenges provide strategies to contain SARS-CoV-2 globally.

9.
Life Sci Alliance ; 5(4)2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34996842

RESUMO

The current COVID-19 pandemic is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The positive-sense single-stranded RNA virus contains a single linear RNA segment that serves as a template for transcription and replication, leading to the synthesis of positive and negative-stranded viral RNA (vRNA) in infected cells. Tools to visualize vRNA directly in infected cells are critical to analyze the viral replication cycle, screen for therapeutic molecules, or study infections in human tissue. Here, we report the design, validation, and initial application of FISH probes to visualize positive or negative RNA of SARS-CoV-2 (CoronaFISH). We demonstrate sensitive visualization of vRNA in African green monkey and several human cell lines, in patient samples and human tissue. We further demonstrate the adaptation of CoronaFISH probes to electron microscopy. We provide all required oligonucleotide sequences, source code to design the probes, and a detailed protocol. We hope that CoronaFISH will complement existing techniques for research on SARS-CoV-2 biology and COVID-19 pathophysiology, drug screening, and diagnostics.

10.
Sci Rep ; 12(1): 188, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34996987

RESUMO

Patients with diabetes are more likely to be infected with Coronavirus disease 2019 (COVID-19), and the risk of death is significantly higher than ordinary patients. Dipeptidyl peptidase-4 (DPP4) is one of the functional receptor of human coronavirus. Exploring the relationship between diabetes mellitus targets and DPP4 is particularly important for the management of patients with diabetes and COVID-19. We intend to study the protein interaction through the protein interaction network in order to find a new clue for the management of patients with diabetes with COVID-19. Diabetes mellitus targets were obtained from GeneCards database. Targets with a relevance score exceeding 20 were included, and DPP4 protein was added manually. The initial protein interaction network was obtained through String. The targets directly related to DPP4 were selected as the final analysis targets. Importing them into String again to obtain the protein interaction network. Module identification, gene ontology (GO) analysis and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis were carried out respectively. The impact of DPP4 on the whole network was analyzed by scoring the module where it located. 43 DPP4-related proteins were finally selected from the diabetes mellitus targets and three functional modules were found by the cluster analysis. Module 1 was involved in insulin secretion and glucagon signaling pathway, module 2 and module 3 were involved in signaling receptor binding. The scoring results showed that LEP and apoB in module 1 were the highest, and the scores of INS, IL6 and ALB of cross module associated proteins of module 1 were the highest. DPP4 is widely associated with key proteins in diabetes mellitus. COVID-19 may affect DPP4 in patients with diabetes mellitus, leading to high mortality of diabetes mellitus combined with COVID-19. DPP4 inhibitors and IL-6 antagonists can be considered to reduce the effect of COVID-19 infection on patients with diabetes.

11.
Sci Rep ; 12(1): 253, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34997145

RESUMO

Vaccine hesitancy is a major global challenge facing COVID-19 immunization programs. Its main source is low public trust in the safety and effectiveness of the vaccine. In a preregistered experimental study, we investigated how using a foreign language when communicating COVID-19 vaccine information influences vaccine acceptance. Hong Kong Chinese residents (N = 611) received COVID-19 vaccine information either in their native Chinese or in English. English increased trust in the safety and effectiveness of the vaccine and, as a result, reduced vaccine hesitancy. This indicates that language can impact vaccine attitudes and demonstrate the potential of language interventions for a low cost, actionable strategy to curtail vaccine hesitancy amongst bilingual populations. Language interventions could contribute towards achieving the United Nations Sustainable Development Goal of health and well-being.

12.
Sci Rep ; 12(1): 263, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34997166

RESUMO

Cold Atmospheric Plasma (CAP) and Plasma Activated Media (PAM) are effective against bacteria, fungi, cancer cells, and viruses because they can deliver Reactive Oxygen and Nitrogen Species (RONS) on a living tissue with negligible damage on health cells. The antiviral activity of CAP against SARS-CoV-2 is being investigated, however, the same but of PAM has not been explored despite its potential. In the present study, the capability of Plasma Activated Media (PAM) to inactivate SARS-CoV-2 and PR8 H1N1 influenza virus with negligible damage on healthy cells is demonstrated. PAM acted by both virus detaching and diminished replication. Furthermore, the treatment of A549 lung cells at different times with buffered PAM did not induce interleukin 8 expression, showing that PAM did not induce inflammation. These results open a new research field by using PAM to the development novel treatments for COVID-19, influenza, and other respiratory diseases.

13.
Rev Med Virol ; 32(1): e2247, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34997677

RESUMO

The outbreak of coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is considered a global catastrophe that has overwhelmed health care systems. Since initiation of the pandemic, identification of characteristics that might influence risk of infection and poor disease outcomes have been of paramount interest. Blood group phenotypes are genetically inherited characteristics whose association with certain infectious diseases have long been debated. The aim of this review is to identify whether a certain type of blood group may influence an individual's susceptibility to SARS-CoV-2 infection and developing severe outcomes. Our review shows that blood group O protects individuals against SARS-CoV-2, whereas blood group A predisposes them to being infected. Although the association between blood groups and outcomes of COVID-19 is not consistent, it is speculated that non-O blood group carriers with COVID-19 are at higher risk of developing severe outcomes in comparison to O blood group. The interaction between blood groups and SARS-CoV-2 infection is hypothesized to be as result of natural antibodies against blood group antigens that may act as a part of innate immune response to neutralize viral particles. Alternatively, blood group antigens could serve as additional receptors for the virus and individuals who are capable of expressing these antigens on epithelial cells, which are known as secretors, would then have a high propensity to be affected by SARS-CoV-2.

14.
Rev Alerg Mex ; 69 Suppl 1: s1-s14, 2022.
Artigo em Espanhol | MEDLINE | ID: mdl-34998305

RESUMO

Even though the SARS-CoV-2 pandemic represents a historical challenge, science has had an exponential development, and the current vaccination campaigns are proof of this. Unfortunately, along came misinformation and myths regarding their production and their adverse effects. For this reason, we have considered of utter importance to review anaphylaxis, one of the most feared vaccine adverse events.Anaphylaxis can be defined as a life-threatening acute and systemic allergic reaction, with a wide clinical spectrum, which can be explained by many immunological mechanisms, and whose diagnostic complexity demands the fulfillment of strict criteria. Though infrequent, any vaccine has the potential to trigger anaphylaxis. In the United States, for the new SARS-CoV-2 vaccines, rates from 1:200 000 (Pfizer-BioNTech) to 1:360 000 doses (Moderna) have been estimated. Vaccine adverse events can be mediated by hypersensitivity reactions, either allergic or not. Unlike a typical drug allergy, rarely is the active ingredient responsible for the reaction. Therefore, excipients must be considered during the approach to this problem. Vaccine associated anaphylaxis has to be referred to an allergist so as to guarantee the maximum benefit for the patient and improve the vaccines' security profile.


Assuntos
Anafilaxia , COVID-19 , Vacinas , Anafilaxia/induzido quimicamente , Vacinas contra COVID-19 , Humanos , SARS-CoV-2 , Estados Unidos , Vacinas/efeitos adversos
15.
Am J Clin Pathol ; 2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-34999740

RESUMO

OBJECTIVES: Emerging severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant strains can be associated with increased transmissibility, more severe disease, and reduced effectiveness of treatments. To improve the availability of regional variant surveillance, we describe a variant genotyping system that is rapid, accurate, adaptable, and able to detect new low-level variants built with existing hospital infrastructure. METHODS: We used a tiered high-throughput SARS-CoV-2 screening program to characterize variants in a supraregional health system over 76 days. Combining targeted reverse transcription-polymerase chain reaction (RT-PCR) and selective sequencing, we screened SARS-CoV-2 reactive samples from all hospitals within our health care system for genotyping dominant and emerging variants. RESULTS: The median turnaround for genotyping was 2 days using the high-throughput RT-PCR-based screen, allowing us to rapidly characterize the emerging Delta variant. In our population, the Delta variant is associated with a lower cycle threshold value, lower age at infection, and increased vaccine-breakthrough cases. Detection of low-level and potentially emerging variants highlights the utility of a tiered approach. CONCLUSIONS: These findings underscore the need for fast, low-cost, high-throughput monitoring of regional viral sequences as the pandemic unfolds and the emergence of SARS-CoV-2 variants increases. Combining RT-PCR-based screening with selective sequencing allows for rapid genotyping of variants and dynamic system improvement.

16.
MAbs ; 14(1): 2013594, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35000569

RESUMO

The ongoing SARS-CoV-2 coronavirus pandemic of 2020-2021 underscores the need for manufacturing platforms that can rapidly produce monoclonal antibody (mAb) therapies. As reported here, a platform based on Nicotiana benthamiana produced mAb therapeutics with high batch-to-batch reproducibility and flexibility, enabling production of 19 different mAbs of sufficient purity and safety for clinical application(s). With a single manufacturing run, impurities were effectively removed for a representative mAb product (the ZMapp component c4G7). Our results show for the first time the reproducibility of the platform for production of multiple batches of clinical-grade mAb, manufactured under current Good Manufacturing Practices, from Nicotiana benthamiana. The flexibility of the system was confirmed by the results of release testing of 19 different mAbs generated with the platform. The process from plant infection to product can be completed within 10 days. Therefore, with a constant supply of plants, response to the outbreak of an infectious disease could be initiated within a matter of weeks. Thus, these data demonstrated that this platform represents a reproducible, flexible system for rapid production of mAb therapeutics to support clinical development.


Assuntos
Anticorpos Monoclonais , Anticorpos Antivirais , COVID-19/imunologia , Plantas Geneticamente Modificadas , SARS-CoV-2/imunologia , Tabaco , Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/química , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/biossíntese , Anticorpos Antivirais/química , Anticorpos Antivirais/genética , Anticorpos Antivirais/imunologia , COVID-19/tratamento farmacológico , Humanos , Plantas Geneticamente Modificadas/química , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/imunologia , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Tabaco/química , Tabaco/genética , Tabaco/crescimento & desenvolvimento , Tabaco/imunologia
17.
J Biosaf Biosecur ; 4(1): 33-37, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35005525

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has evolved rapidly into new variants throughout the pandemic. The Omicron variant has more than 50 mutations when compared with the original wild-type strain and has been identified globally in numerous countries. In this report, we analyzed the mutational profiles of several variants, including the per-site mutation rate, to determine evolutionary relationships. The Omicron variant was found to have a unique mutation profile when compared with that of other SARS-CoV-2 variants, containing mutations that are rare in clinical samples. Moreover, the presence of five mouse-adapted mutation sites suggests that Omicron may have evolved in a mouse host. Mutations in the Omicron receptor-binding domain (RBD) region, in particular, have potential implications for the ongoing pandemic.

18.
Bull Math Biol ; 84(2): 30, 2022 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-35006388

RESUMO

The COVID-19 pandemic has adversely affected the entire world. The effective implementation of vaccination strategy is critical to prevent the resurgence of the pandemic, especially during large-scale population migration. We establish a multiple patch coupled model based on the transportation network among the 31 provinces in China, under the combined strategies of vaccination and quarantine during large-scale population migration. Based on the model, we derive a critical quarantine rate to control the pandemic transmission and a vaccination rate to achieve herd immunity. Furthermore, we evaluate the influence of passenger flow on the effective reproduction number during the Chinese-Spring-Festival travel rush. Meanwhile, the spread of the COVID-19 pandemic is investigated for different control strategies, viz. global control and local control. The impact of vaccine-related parameters, such as the number, the effectiveness and the immunity period of vaccine, are explored. It is believed that the articulated models as well as the presented simulation results could be beneficial to design of feasible strategies for preventing COVID-19 transmission during the Chinese-Spring-Festival travel rush or the other future events involving large-scale population migration.


Assuntos
COVID-19 , Quarentena , China/epidemiologia , Férias e Feriados , Humanos , Conceitos Matemáticos , Modelos Biológicos , Pandemias/prevenção & controle , SARS-CoV-2 , Viagem , Vacinação
19.
PLoS One ; 17(1): e0261242, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35007307

RESUMO

Hyperactive and damaging inflammation is a hallmark of severe rather than mild Coronavirus disease 2019 (COVID-19). To uncover key inflammatory differentiators between severe and mild COVID-19, we applied an unbiased single-cell transcriptomic analysis. We integrated two single-cell RNA-seq datasets with COVID-19 patient samples, one that sequenced bronchoalveolar lavage (BAL) cells and one that sequenced peripheral blood mononuclear cells (PBMCs). The combined cell population was then analyzed with a focus on genes associated with disease severity. The immunomodulatory long non-coding RNAs (lncRNAs) NEAT1 and MALAT1 were highly differentially expressed between mild and severe patients in multiple cell types. Within those same cell types, the concurrent detection of other severity-associated genes involved in cellular stress response and apoptosis regulation suggests that the pro-inflammatory functions of these lncRNAs may foster cell stress and damage. Thus, NEAT1 and MALAT1 are potential components of immune dysregulation in COVID-19 that may provide targets for severity related diagnostic measures or therapy.

20.
Chem Biol Interact ; 353: 109796, 2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-35007526

RESUMO

Coronavirus disease 2019 (COVID-19) was declared a serious global public health emergency. Hospitalization and mortality rates of lung cancer patients diagnosed with COVID-19 are higher than those of patients presenting with other cancers. However, the reasons for the outcomes being disproportionately severe in lung adenocarcinoma (LUAD) patients with COVID-19 remain elusive. The present study aimed to identify the possible causes for disproportionately severe COVID-19 outcomes in LUAD patients and determine a therapeutic target for COVID-19 patients with LUAD. We used publicly available data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases and various bioinformatics tools to identify and analyze the genes implicated in SARS-CoV-2 infection in LUAD patients. Upregulation of the SARS-CoV-2 infection-related molecules dipeptidyl peptidase 4, basigin, cathepsin B (CTSB), methylenetetrahydrofolate dehydrogenase, and peptidylprolyl isomerase B rather than angiotensin-converting enzyme 2 may explain the relatively high susceptibility of LUAD patients to SARS-CoV-2 infection. CTSB was highly expressed in the LUAD tissues after SARS-CoV-2 infection, and its expression was positively correlated with immune cell infiltration and proinflammatory cytokine expression. These findings suggest that CTSB plays a vital role in the hyperinflammatory response in COVID-19 patients with LUAD and is a promising target for the development of a novel drug therapy for COVID-19 patients.

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