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1.
Drug Discov Ther ; 14(4): 153-160, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32908070

RESUMO

The COVID-19 infection has been a matter of urgency to tackle around the world today, there exist 200 countries around the world and 54 countries in Africa that the COVID-19 infection cases have been confirmed. This situation prompted us to look into the challenges African laboratories are facing in the diagnosis of novel COVID-19 infection. A limited supply of essential laboratory equipment and test kits are some of the challenges faced in combatting the novel virus in Africa. Also, there is inadequate skilled personnel, which might pose a significant danger in case there is a surge in COVID-19 infection cases. The choice of diagnostic method in Africa is limited as there are only two available diagnostic methods being used out of the six methods used globally, thereby reducing the opportunity of supplementary diagnosis, which will further lead to inappropriate diagnosis and affect the accuracy of diagnostic reports. Furthermore, challenges like inadequate power supply, the method used in sample collection, storage and transportation of specimens are also significant as they also pose their respective implication. From the observations, there is an urgent need for more investment into the laboratories for proper, timely, and accurate diagnosis of COVID-19.


Assuntos
Betacoronavirus/isolamento & purificação , Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico , Acesso aos Serviços de Saúde/organização & administração , Necessidades e Demandas de Serviços de Saúde/organização & administração , Pneumonia Viral/diagnóstico , Virologia/organização & administração , Betacoronavirus/patogenicidade , Orçamentos , Técnicas de Laboratório Clínico/economia , Infecções por Coronavirus/economia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Custos de Cuidados de Saúde , Acesso aos Serviços de Saúde/economia , Necessidades e Demandas de Serviços de Saúde/economia , Humanos , Nigéria/epidemiologia , Pandemias/economia , Pneumonia Viral/economia , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Carga Viral , Virologia/economia , Fluxo de Trabalho
2.
Biosens Bioelectron ; 166: 112436, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32750677

RESUMO

Our recent experience of the COVID-19 pandemic has highlighted the importance of easy-to-use, quick, cheap, sensitive and selective detection of virus pathogens for the efficient monitoring and treatment of virus diseases. Early detection of viruses provides essential information about possible efficient and targeted treatments, prolongs the therapeutic window and hence reduces morbidity. Graphene is a lightweight, chemically stable and conductive material that can be successfully utilized for the detection of various virus strains. The sensitivity and selectivity of graphene can be enhanced by its functionalization or combination with other materials. Introducing suitable functional groups and/or counterparts in the hybrid structure enables tuning of the optical and electrical properties, which is particularly attractive for rapid and easy-to-use virus detection. In this review, we cover all the different types of graphene-based sensors available for virus detection, including, e.g., photoluminescence and colorimetric sensors, and surface plasmon resonance biosensors. Various strategies of electrochemical detection of viruses based on, e.g., DNA hybridization or antigen-antibody interactions, are also discussed. We summarize the current state-of-the-art applications of graphene-based systems for sensing a variety of viruses, e.g., SARS-CoV-2, influenza, dengue fever, hepatitis C virus, HIV, rotavirus and Zika virus. General principles, mechanisms of action, advantages and drawbacks are presented to provide useful information for the further development and construction of advanced virus biosensors. We highlight that the unique and tunable physicochemical properties of graphene-based nanomaterials make them ideal candidates for engineering and miniaturization of biosensors.


Assuntos
Betacoronavirus/isolamento & purificação , Técnicas Biossensoriais , Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico , Grafite , Pneumonia Viral/diagnóstico , Vírus/isolamento & purificação , Reações Antígeno-Anticorpo , Betacoronavirus/genética , Betacoronavirus/patogenicidade , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/tendências , Técnicas de Laboratório Clínico/instrumentação , Técnicas de Laboratório Clínico/métodos , Técnicas de Laboratório Clínico/estatística & dados numéricos , Colorimetria , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , DNA Viral/análise , DNA Viral/genética , Técnicas Eletroquímicas , Desenho de Equipamento , Grafite/química , Humanos , Luminescência , Nanoestruturas/química , Hibridização de Ácido Nucleico , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , Pontos Quânticos/química , Análise Espectral Raman , Ressonância de Plasmônio de Superfície , Virologia/métodos , Vírus/genética , Vírus/patogenicidade
3.
J Nutr Health Aging ; 24(7): 685-691, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32744561

RESUMO

A new coronavirus, called SARS-CoV-2, was identified in Wuhan, China, in December 2019. The SARS-CoV-2 spread very rapidly, causing a global pandemic, Coronavirus Disease 2019 (COVID-19). Older adults have higher peak of viral load and, especially those with comorbidities, had higher COVID-19-related fatality rates than younger adults. In this Perspective paper, we summarize current knowledge about SARS-CoV-2 and aging, in order to understand why older people are more affected by COVID-19. We discuss about the possibility that the so-called "immunosenescence" and "inflammaging" processes, already present in a fraction of frail older adults, could allow the immune escape of SARS-CoV-2 leading to COVID-19 serious complications. Finally, we propose to use geroscience approaches to the field of COVID-19.


Assuntos
Envelhecimento , Betacoronavirus , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Geriatria , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , Virologia , Idoso , Envelhecimento/imunologia , Envelhecimento/patologia , Humanos , Inflamação/imunologia , Inflamação/patologia , Pandemias
7.
Nat Commun ; 11(1): 3505, 2020 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-32665593

RESUMO

The early steps of HIV-1 infection, such as uncoating, reverse transcription, nuclear import, and transport to integration sites are incompletely understood. Here, we imaged nuclear entry and transport of HIV-1 replication complexes in cell lines, primary monocyte-derived macrophages (MDMs) and CD4+ T cells. We show that viral replication complexes traffic to and accumulate within nuclear speckles and that these steps precede the completion of viral DNA synthesis. HIV-1 transport to nuclear speckles is dependent on the interaction of the capsid proteins with host cleavage and polyadenylation specificity factor 6 (CPSF6), which is also required to stabilize the association of the viral replication complexes with nuclear speckles. Importantly, integration site analyses reveal a strong preference for HIV-1 to integrate into speckle-associated genomic domains. Collectively, our results demonstrate that nuclear speckles provide an architectural basis for nuclear homing of HIV-1 replication complexes and subsequent integration into associated genomic loci.


Assuntos
Infecções por HIV/virologia , HIV-1/patogenicidade , Linfócitos T CD4-Positivos/metabolismo , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Núcleo Celular/genética , Núcleo Celular/metabolismo , Genoma Viral/genética , Células HEK293 , Infecções por HIV/genética , HIV-1/genética , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/fisiologia , Humanos , Microscopia de Fluorescência , Virologia , Integração Viral/genética , Integração Viral/fisiologia , Replicação Viral/genética , Replicação Viral/fisiologia
11.
Forensic Sci Med Pathol ; 16(3): 457-462, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32578131

RESUMO

Death due to respiratory infection is commonly encountered at autopsy. With only one opportunity to obtain samples for identification of a causative agent, it is important to ensure that sampling regimes are optimized to provide the greatest detection, without the expense and redundancy that can arise from over-sampling. This study was performed retrospectively using data from Coronial autopsies over the period 2012-2019 from which swabs from the nasopharyngeal region, trachea and lung parenchyma, in addition to samples of lung tissue, had been submitted for multiplex PCR detection of respiratory pathogens. From 97 cases with all four samples, there were 24 with at least one positive result for viral infection. Some cases had multiple positive results and a total of 27 respiratory tract viruses were identified, of which rhinovirus, influenza A virus and respiratory syncytial virus were the most common. Seventeen of the 27 viral infections (63%) were identified in all four samples. However, in nearly all cases (96%) the nasopharyngeal swab detected the infective agent when the multiplex PCR panel had detected infection in any of the four sample types. A nasopharyngeal swab is considered to be an optimal sample for detection of respiratory tract viral infection. As the samples analyzed were acquired before the appearance of the COVID-19 virus, the applicability of this finding for COVID-19 screening is not established.


Assuntos
DNA Viral/isolamento & purificação , Pulmão/virologia , Reação em Cadeia da Polimerase Multiplex , Nasofaringe/virologia , Infecções Respiratórias/diagnóstico , Manejo de Espécimes , Virologia , Viroses/diagnóstico , Vírus/isolamento & purificação , Adulto , Idoso , Idoso de 80 Anos ou mais , Autopsia , Causas de Morte , DNA Viral/classificação , DNA Viral/genética , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Infecções Respiratórias/virologia , Estudos Retrospectivos , Viroses/virologia , Vírus/classificação , Vírus/genética
12.
Sheng Wu Gong Cheng Xue Bao ; 36(5): 879-890, 2020 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-32567271

RESUMO

Human parvovirus B19 (B19 virus) is one of the two parvoviruses that cause human diseases. As an important pathogen to humans, it causes infectious erythema in children, acute aplastic anemia, fetal edema and death. In this review, we focus on the recent advances in the molecular virology of B19V, such as viral genotypes, viral receptor, genomic features and viral replication, viral transcription and post-transcription regulation, viral nonstructural and structural protein features and functions, viral diagnosis and antiviral agents, to provide reference for further study of B19 pathogenesis mechanisms, treatment and diagnostic strategies.


Assuntos
Parvovirus B19 Humano , Virologia , Antivirais , DNA Viral/genética , Eritema Infeccioso/diagnóstico , Eritema Infeccioso/virologia , Genótipo , Humanos , Parvovirus B19 Humano/genética , Virologia/tendências , Replicação Viral
14.
Forensic Sci Med Pathol ; 16(3): 471-476, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32399755

RESUMO

SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) is a coronavirus responsible for COVID-19 (coronavirus disease 2019) which resulted in a cluster of cases of pneumonia that originated in China around 31 December 2019 and has subsequently spread across the globe. Currently, COVID-19 represents a health emergency worldwide, leading, in severe cases, to pneumonia, severe acute respiratory syndrome, multiorgan dysfunction or failure, and death. In the context of limited scientific knowledge and evidence of SARS-CoV-2 infection, guidance is becoming increasingly necessary for pathologists who have to perform postmortem investigations on COVID-19 cases. The aim of the present report is to share a procedure applicable to cases of COVID-19-related death, particularly in cases of death without medical intervention and in the absence of an ascertained SARS-CoV-2 infection and/or COVID-19 diagnosis, therefore providing support for diagnostic activity in the present COVID-19 pandemic. For this purpose, a standard operating procedure for correct swab collection, autopsy investigation and tissue sampling is provided.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/mortalidade , Ciências Forenses/normas , Pneumonia Viral/diagnóstico , Pneumonia Viral/mortalidade , Sistema Respiratório/virologia , Manejo de Espécimes/normas , Virologia/normas , Autopsia , Causas de Morte , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Interações entre Hospedeiro e Microrganismos , Humanos , Itália , Pandemias , Pneumonia Viral/patologia , Pneumonia Viral/virologia , Valor Preditivo dos Testes , Sistema Respiratório/patologia
17.
J Med Internet Res ; 22(4): e19076, 2020 04 27.
Artigo em Inglês | MEDLINE | ID: covidwho-125505

RESUMO

BACKGROUND: At the onset of the coronavirus outbreak, the World Health Organization's (WHO) Health Emergencies Learning and Capacity Development Unit, together with the WHO's health technical lead on coronaviruses, developed a massive open online course within 3 weeks as part of the global response to the emergency. The introductory coronavirus disease (COVID­19) course was launched on January 26, 2020, on the health emergencies learning platform OpenWHO.org. OBJECTIVE: The aim of this paper is to investigate the geographic reach of different language courses accessed by a worldwide audience seeking information on COVID-19. Users' professional identities and backgrounds were explored to inform course owners on the use case. The course was developed and delivered via the open-access learning platform OpenWHO.org. The self-paced resources are available in a total of 13 languages and were produced between January 26 and March 25, 2020. METHODS: Data were collected from the online courses' statistical data and metrics reporting system on the OpenWHO platform. User patterns and locations were analyzed based on Google Analytics and the platform's own statistics capabilities, and data sets were overlaid. This analysis was conducted based on user location, with the data disaggregated according to the six WHO regions, the top 10 countries, and the proportion of use for each language version. Data included affiliation, gender, age, and other parameters for 32.43% (52,214/161,007) of the users who indicated their background. RESULTS: As of March 25, 2020, the introductory COVID-19 course totaled 232,890 enrollments across all languages. The Spanish language course was comprised of more than half (n=118,754, 50.99%) of all course enrollments, and the English language course was comprised of 38.21% (n=88,988) of enrollments. The WHO's Region of the Americas accounted for most of the course enrollments, with more than 72.47% (138,503/191,130) enrollment across all languages. Other regions were more evenly distributed with less than 10% enrollment for each. A total of 32.43% (52,214/161,007) of users specified a professional affiliation by choosing from the 12 most common backgrounds in the OpenWHO user profiles. Before the COVID-19 pandemic, users were spread over the 11 distinct affiliations, with a small fraction of users identifying themselves as "Other." With the COVID-19 introductory course, the largest number of users selected "Other" (16,527/52,214, 31.65%), suggesting a large number of users who were not health professionals or academics. The top 10 countries with the most users across all languages were Argentina, Chile, Colombia, Ecuador, India, Mexico, Peru, Spain, the United Kingdom, and the United States. CONCLUSIONS: The online course has addressed a worldwide learning need by providing WHO's technical guidance packaged in simple formats for access and use. The learning material development was expedited to meet the onset of the epidemic. Initial data suggest that the various language versions of the course, in particular Spanish, have reached new user groups, fulfilling the platform's aim of providing learning everywhere to anyone that is interested. User surveys will be carried out to measure the real impact.


Assuntos
Betacoronavirus , Infecções por Coronavirus , Educação a Distância/estatística & dados numéricos , Internacionalidade , Idioma , Pandemias , Pneumonia Viral , Estudantes/estatística & dados numéricos , Organização Mundial da Saúde/organização & administração , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Interpretação Estatística de Dados , Humanos , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , Virologia/educação
19.
J Med Internet Res ; 22(4): e19076, 2020 04 27.
Artigo em Inglês | MEDLINE | ID: covidwho-68158

RESUMO

BACKGROUND: At the onset of the coronavirus outbreak, the World Health Organization's (WHO) Health Emergencies Learning and Capacity Development Unit, together with the WHO's health technical lead on coronaviruses, developed a massive open online course within 3 weeks as part of the global response to the emergency. The introductory coronavirus disease (COVID­19) course was launched on January 26, 2020, on the health emergencies learning platform OpenWHO.org. OBJECTIVE: The aim of this paper is to investigate the geographic reach of different language courses accessed by a worldwide audience seeking information on COVID-19. Users' professional identities and backgrounds were explored to inform course owners on the use case. The course was developed and delivered via the open-access learning platform OpenWHO.org. The self-paced resources are available in a total of 13 languages and were produced between January 26 and March 25, 2020. METHODS: Data were collected from the online courses' statistical data and metrics reporting system on the OpenWHO platform. User patterns and locations were analyzed based on Google Analytics and the platform's own statistics capabilities, and data sets were overlaid. This analysis was conducted based on user location, with the data disaggregated according to the six WHO regions, the top 10 countries, and the proportion of use for each language version. Data included affiliation, gender, age, and other parameters for 32.43% (52,214/161,007) of the users who indicated their background. RESULTS: As of March 25, 2020, the introductory COVID-19 course totaled 232,890 enrollments across all languages. The Spanish language course was comprised of more than half (n=118,754, 50.99%) of all course enrollments, and the English language course was comprised of 38.21% (n=88,988) of enrollments. The WHO's Region of the Americas accounted for most of the course enrollments, with more than 72.47% (138,503/191,130) enrollment across all languages. Other regions were more evenly distributed with less than 10% enrollment for each. A total of 32.43% (52,214/161,007) of users specified a professional affiliation by choosing from the 12 most common backgrounds in the OpenWHO user profiles. Before the COVID-19 pandemic, users were spread over the 11 distinct affiliations, with a small fraction of users identifying themselves as "Other." With the COVID-19 introductory course, the largest number of users selected "Other" (16,527/52,214, 31.65%), suggesting a large number of users who were not health professionals or academics. The top 10 countries with the most users across all languages were Argentina, Chile, Colombia, Ecuador, India, Mexico, Peru, Spain, the United Kingdom, and the United States. CONCLUSIONS: The online course has addressed a worldwide learning need by providing WHO's technical guidance packaged in simple formats for access and use. The learning material development was expedited to meet the onset of the epidemic. Initial data suggest that the various language versions of the course, in particular Spanish, have reached new user groups, fulfilling the platform's aim of providing learning everywhere to anyone that is interested. User surveys will be carried out to measure the real impact.


Assuntos
Betacoronavirus , Infecções por Coronavirus , Educação a Distância/estatística & dados numéricos , Internacionalidade , Idioma , Pandemias , Pneumonia Viral , Estudantes/estatística & dados numéricos , Organização Mundial da Saúde/organização & administração , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Interpretação Estatística de Dados , Humanos , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , Virologia/educação
20.
Avian Dis ; 64(1): 85-91, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32267129

RESUMO

Avian influenza A viruses are a major threat to animal and public health. Since 1997, several highly pathogenic H5N1 avian viruses have been directly transmitted from poultry to humans, caused numerous human deaths, and had considerable economic impact on poultry markets. During 2015-2016, a highly pathogenic avian influenza outbreak occurred in southwestern France. Different subtypes circulated, including the A/chicken/France/150169a/2015 H5N1 highly pathogenic virus, which did not possess the full set of genomic determinants known to promote transmission to humans. In order to evaluate the predicted absence of zoonotic potential, a quick method based on in vitro tests was developed to analyze some genetic and phenotypic host restriction determinants. A receptor-binding assay showed that the virus preferentially recognizes avian cell receptors. Temperature sensitivity revealed a cold-sensitive phenotype of the virus at 33 C as virus replication was reduced in contrast with what is expected for human influenza viruses, according to their primary infection sites. Altogether, our quick evaluation method suggests that the A/chicken/France/150169a/2015 H5N1 highly pathogenic virus has an avian phenotype in vitro, in accordance with in silico predictions based on genomic markers.


Assuntos
Galinhas , Técnicas In Vitro/veterinária , Virus da Influenza A Subtipo H5N1/fisiologia , Influenza Aviária/virologia , Doenças das Aves Domésticas/virologia , Tropismo Viral , Animais , França , Técnicas In Vitro/métodos , Virologia/métodos
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