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3.
J Virol ; 96(18): e0130522, 2022 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-36094313

RESUMO

Curriculum guidelines for virology are needed to best guide student learning due to the continuous and ever-increasing volume of virology information, the need to ensure that undergraduate and graduate students have a foundational understanding of key virology concepts, and the importance in being able to communicate that understanding to both other virologists and nonvirologists. Such guidelines, developed by virology educators and the American Society for Virology Education and Career Development Committee, are described herein.


Assuntos
Currículo , Universidades , Virologia , Educação de Pós-Graduação , Estados Unidos , Virologia/educação
4.
J Virol ; 96(18): e0084922, 2022 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-36037476

RESUMO

The existing cell culture-based methods to study hepatitis B virus (HBV) have limitations and do not allow for viral long-term passage. The aim of this study was to develop a robust in vitro long-term viral passage system with optimized cell culture conditions and a viral isolate with the ability to spread and passage. An HBV genotype A clinical isolate was subjected to multiple rounds of UV treatment and passaged in an optimized primary human hepatocyte (PHH)/human fibroblast coculture system. The passaged UV-treated virus was sequenced and further characterized. In addition, a panel of mutant viruses containing different combinations of mutations observed in this virus was investigated. The clinical isolate was passaged for 20 rounds with 21 days per round in an optimized PHH/human fibroblast coculture system while subject to UV mutagenesis. This passaged UV-mutated isolate harbored four mutations: G225A (sR24K) in the S gene, A2062T in the core gene, and two mutations G1764A and C1766T (xV131I) in the basal core promoter (BCP) region. In vitro characterization of the four mutations suggested that the two BCP mutations G1764A and C1766T contributed to the increased viral replication and viral infectivity. A robust in vitro long-term HBV viral passage system has been established by passaging a UV-treated clinical isolate in an optimized PHH/fibroblast coculture system. The two BCP mutations played a key role in the virus's ability to passage. This passage system can be used for studying the entire life cycle of HBV and has the potential for in vitro drug-resistance selection upon further optimization. IMPORTANCE The existing cell culture-based methods to study HBV have limitations and do not allow for viral long-term passage. In this study, an HBV genotype A clinical isolate was subjected to multiple rounds of UV treatment and passaged in an optimized PHH/human fibroblast coculture system. This passaged UV-mutated isolate carried four mutations across the HBV genome, and in vitro characterization of the four mutations suggested that the two basal core promoter (BCP) mutations G1764A and C1766T played a key role in the virus's ability to passage. In summary, we have developed a robust in vitro long-term HBV viral passage system by passaging an UV-treated HBV genotype A clinical isolate in an optimized PHH/human fibroblast coculture system. This passage system can be used for studying the entire life cycle of HBV and has the potential for in vitro drug-resistance selection upon further optimization.


Assuntos
Técnicas de Cocultura , Vírus da Hepatite B , Hepatite B , Virologia , DNA Viral/genética , Fibroblastos/virologia , Genótipo , Hepatite B/virologia , Vírus da Hepatite B/genética , Hepatócitos/virologia , Humanos , Mutagênese , Mutação , Virologia/métodos , Replicação Viral
6.
Nature ; 607(7918): 247-248, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35768603
7.
Viruses ; 14(6)2022 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-35746773

RESUMO

The Czech Republic, a part of the former Czechoslovakia, has been at the forefront of several research directions in virology, genetics and physiology [...].


Assuntos
Virologia , República Tcheca
10.
Nature ; 603(7903): 784-786, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35354995
11.
J Cell Biol ; 221(3)2022 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-35195660

RESUMO

Bo Zhong studies the regulation of the antiviral innate immunity, inflammation, and tumorigenesis by the protein ubiquitination system.


Assuntos
Alergia e Imunologia/história , Imunidade Inata , Ubiquitinação , Virologia/história , Animais , China , História do Século XXI , Interações Hospedeiro-Patógeno , Humanos
12.
Int J Biol Sci ; 18(3): 901-910, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35173525

RESUMO

The coronavirus disease 2019 (COVID-19) global pandemic evoked by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has triggered a major public health problem with significant morbidity and mortality. Understanding the pathogenesis and molecular mechanisms underlying this novel virus is crucial for both fundamental research and clinical trials in order to devise effective therapies and vaccination regimens. Basic research on SARS-CoV-2 largely depends on ex vivo models that allow viral invasion and replication. Organoid models are now emerging as a valuable tool to investigate viral biology and disease progression, serving as an efficient platform to investigate potential therapies for COVID-19. Here, we summarize various human stem cell-derived organoid types employed in SARS-CoV-2 studies. We highlight key findings from these models, including cell tropisms and molecular mechanisms in viral infection. We also describe their use in identifying potential therapeutic agents against SARS-CoV-2. As more and more advanced organoids emerge, they will facilitate the understanding of disease pathogenesis for drug development in this dreaded pandemic.


Assuntos
COVID-19 , Organoides , SARS-CoV-2 , Virologia/métodos , Humanos
13.
Viruses ; 14(2)2022 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-35215784

RESUMO

Almost two decades after the isolation of the first amoebal giant viruses, indubitably the discovery of these entities has deeply affected the current scientific knowledge on the virosphere. Much has been uncovered since then: viruses can now acknowledge complex genomes and huge particle sizes, integrating remarkable evolutionary relationships that date as early as the emergence of life on the planet. This year, a decade has passed since the first studies on giant viruses in the Brazilian territory, and since then biomes of rare beauty and biodiversity (Amazon, Atlantic forest, Pantanal wetlands, Cerrado savannas) have been explored in the search for giant viruses. From those unique biomes, novel viral entities were found, revealing never before seen genomes and virion structures. To celebrate this, here we bring together the context, inspirations, and the major contributions of independent Brazilian research groups to summarize the accumulated knowledge about the diversity and the exceptionality of some of the giant viruses found in Brazil.


Assuntos
Amoeba/virologia , Vírus Gigantes/genética , Vírus Gigantes/isolamento & purificação , Virologia/história , Biodiversidade , Brasil , Ecossistema , Genoma Viral , Vírus Gigantes/classificação , Vírus Gigantes/ultraestrutura , História do Século XXI , Filogenia
14.
Sci Rep ; 12(1): 2311, 2022 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-35145121

RESUMO

Many studies have been conducted on measuring avian influenza viruses and their hemagglutinin (HA) antigens via electrochemical principles; most of these studies have used gold electrodes on ceramic, glass, or silicon substrates, and/or labeling for signal enhancement. Herein, we present a paper-based immunosensor for label-free measurement of multiple avian influenza virus (H5N1, H7N9, and H9N2) antigens using flexible screen-printed carbon nanotube-polydimethylsiloxane electrodes. These flexible electrodes on a paper substrate can complement the physical weakness of the paper-based sensors when wetted, without affecting flexibility. The relative standard deviation of the peak currents was 1.88% when the electrodes were repeatedly bent and unfolded twenty times with deionized water provided each cycle, showing the stability of the electrodes. For the detection of HA antigens, approximately 10-µl samples (concentration: 100 pg/ml-100 ng/ml) were needed to form the antigen-antibody complexes during 20-30 min incubation, and the immune responses were measured via differential pulse voltammetry. The limits of detections were 55.7 pg/ml (0.95 pM) for H5N1 HA, 99.6 pg/ml (1.69 pM) for H7N9 HA, and 54.0 pg/ml (0.72 pM) for H9N2 HA antigens in phosphate buffered saline, and the sensors showed good selectivity and reproducibility. Such paper-based sensors are economical, flexible, robust, and easy-to-manufacture, with the ability to detect several avian influenza viruses.


Assuntos
Antígenos Virais/análise , Técnicas Biossensoriais/métodos , Dimetilpolisiloxanos , Técnicas Eletroquímicas/métodos , Eletrodos , Imunoensaio/métodos , Virus da Influenza A Subtipo H5N1/imunologia , Subtipo H7N9 do Vírus da Influenza A/imunologia , Vírus da Influenza A Subtipo H9N2/imunologia , Nanotubos de Carbono , Papel , Virologia/métodos , Animais , Aves , Humanos , Influenza Aviária/diagnóstico , Influenza Aviária/virologia , Influenza Humana/diagnóstico , Influenza Humana/virologia , Limite de Detecção , Reprodutibilidade dos Testes
16.
Nature ; 602(7895): 142-147, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35082445

RESUMO

Public databases contain a planetary collection of nucleic acid sequences, but their systematic exploration has been inhibited by a lack of efficient methods for searching this corpus, which (at the time of writing) exceeds 20 petabases and is growing exponentially1. Here we developed a cloud computing infrastructure, Serratus, to enable ultra-high-throughput sequence alignment at the petabase scale. We searched 5.7 million biologically diverse samples (10.2 petabases) for the hallmark gene RNA-dependent RNA polymerase and identified well over 105 novel RNA viruses, thereby expanding the number of known species by roughly an order of magnitude. We characterized novel viruses related to coronaviruses, hepatitis delta virus and huge phages, respectively, and analysed their environmental reservoirs. To catalyse the ongoing revolution of viral discovery, we established a free and comprehensive database of these data and tools. Expanding the known sequence diversity of viruses can reveal the evolutionary origins of emerging pathogens and improve pathogen surveillance for the anticipation and mitigation of future pandemics.


Assuntos
Computação em Nuvem , Bases de Dados Genéticas , Vírus de RNA/genética , Vírus de RNA/isolamento & purificação , Alinhamento de Sequência/métodos , Virologia/métodos , Viroma/genética , Animais , Arquivos , Bacteriófagos/enzimologia , Bacteriófagos/genética , Biodiversidade , Coronavirus/classificação , Coronavirus/enzimologia , Coronavirus/genética , Evolução Molecular , Vírus Delta da Hepatite/enzimologia , Vírus Delta da Hepatite/genética , Humanos , Modelos Moleculares , Vírus de RNA/classificação , Vírus de RNA/enzimologia , RNA Polimerase Dependente de RNA/química , RNA Polimerase Dependente de RNA/genética , Software
17.
Methods Mol Biol ; 2407: 45-55, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34985656

RESUMO

Models to study HIV latency have improved our understanding of the mechanisms involved in this process and have helped in the discovery and development of therapeutic strategies to eradicate HIV. Primary cell models are based on the in vitro generation of latently infected cells using CD4T cells isolated from blood, lymph nodes or other lymphoid organs. In this chapter, we describe the generation of HIV latently infected memory CD4T cells using blood naïve CD4T cells from peripheral blood with a phenotype resembling that of central memory CD4T cells. This model can be used to investigate the mechanisms involved in latency as well to develop strategies to target it.


Assuntos
Infecções por HIV , HIV-1 , Virologia , Latência Viral , Linfócitos T CD4-Positivos , Células Cultivadas , Infecções por HIV/patologia , Infecções por HIV/virologia , Humanos , Fenótipo , Virologia/métodos , Replicação Viral
18.
BMC Urol ; 22(1): 10, 2022 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-35093044

RESUMO

BACKGROUND: Routine human papillomavirus (HPV) testing is performed in cervival cancer and is required for classification of some head and neck cancers. In penile cancer a statement on HPV association of the carcinoma is required. In most cases p16 immunohistochemistry as a surrogate marker is applied in this setting. Since differing clinical outcomes for HPV positive and HPV negative tumors are described we await HPV testing to be requested more frequently by clinicians, also in the context of HPV vaccination, where other HPV subtypes are expected to emerge. METHOD: Therefore, a cohort of archived, formalin-fixed paraffin embedded (FFPE) penile neoplasias was stained for p16 and thereafter tested for HPV infection status via PCR based methods. Additionally to Sanger sequencing, we chose LCD-Array technique (HPV 3.5 LCD-Array Kit, Chipron; LCD-Array) for the detection of HPV in our probes expecting a less time consuming and sensitive HPV test for our probes. RESULTS: We found that LCD-Array is a sensitive and feasible method for HPV testing in routine diagnostics applicable to FFPE material in our cohort. Our cohort of penile carcinomas and carcinomas in situ was associated with HPV infection in 61% of cases. We detected no significant association between HPV infection status and histomorphological tumor characteristics as well as overall survival. CONCLUSIONS: We showed usability of molecular HPV testing on a cohort of archived penile carcinomas. To the best of our knowledge, this is the first study investigating LCD-Array technique on a cohort of penile neoplasias.


Assuntos
Papillomaviridae/classificação , Infecções por Papillomavirus/complicações , Neoplasias Penianas/virologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Penianas/diagnóstico , Virologia/métodos
19.
Sci Rep ; 12(1): 491, 2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-35017574

RESUMO

Up to 170 tick-borne viruses (TBVs) have been identified to date. However, there is a paucity of information regarding TBVs and their interaction with respective vectors, limiting the development of new effective and urgently needed control methods. To overcome this gap of knowledge, it is essential to reproduce transmission cycles under controlled laboratory conditions. In this study we assessed an artificial feeding system (AFS) and an immersion technique (IT) to infect Ixodes ricinus ticks with tick-borne encephalitis (TBE) and Kemerovo (KEM) virus, both known to be transmitted predominantly by ixodid ticks. Both methods permitted TBEV acquisition by ticks and we further confirmed virus trans-stadial transmission and onward transmission to a vertebrate host. However, only artificial feeding system allowed to demonstrate both acquisition by ticks and trans-stadial transmission for KEMV. Yet we did not observe transmission of KEMV to mice (IFNAR-/- or BALB/c). Artificial infection methods of ticks are important tools to study tick-virus interactions. When optimally used under laboratory settings, they provide important insights into tick-borne virus transmission cycles.


Assuntos
Vetores Aracnídeos/virologia , Vírus da Encefalite Transmitidos por Carrapatos/fisiologia , Encefalite Transmitida por Carrapatos/transmissão , Ixodes/virologia , Orbivirus/fisiologia , Infecções por Reoviridae/transmissão , Virologia/métodos , Animais , Vetores Aracnídeos/fisiologia , Encefalite Transmitida por Carrapatos/virologia , Interações Hospedeiro-Patógeno , Humanos , Ixodes/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Reoviridae/virologia
20.
J Nanobiotechnology ; 20(1): 41, 2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35062978

RESUMO

Early detection of viral pathogens by DNA-sensors in clinical samples, contaminated foods, soil or water can dramatically improve clinical outcomes and reduce the socioeconomic impact of diseases such as COVID-19. Clustered regularly interspaced short palindromic repeat (CRISPR) and its associated protein Cas12a (previously known as CRISPR-Cpf1) technology is an innovative new-generation genomic engineering tool, also known as 'genetic scissors', that has demonstrated the accuracy and has recently been effectively applied as appropriate (E-CRISPR) DNA-sensor to detect the nucleic acid of interest. The CRISPR-Cas12a from Prevotella and Francisella 1 are guided by a short CRISPR RNA (gRNA). The unique simultaneous cis- and trans- DNA cleavage after target sequence recognition at the PAM site, sticky-end (5-7 bp) employment, and ssDNA/dsDNA hybrid cleavage strategies to manipulate the attractive nature of CRISPR-Cas12a are reviewed. DNA-sensors based on the CRISPR-Cas12a technology for rapid, robust, sensitive, inexpensive, and selective detection of virus DNA without additional sample purification, amplification, fluorescent-agent- and/or quencher-labeling are relevant and becoming increasingly important in industrial and medical applications. In addition, CRISPR-Cas12a system shows great potential in the field of E-CRISPR-based bioassay research technologies. Therefore, we are highlighting insights in this research direction.


Assuntos
Sistemas CRISPR-Cas/fisiologia , DNA Viral/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico , Animais , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/tendências , COVID-19/virologia , DNA Viral/análise , Poluentes Ambientais/análise , Poluentes Ambientais/isolamento & purificação , Contaminação de Alimentos/análise , Humanos , Tipagem Molecular/métodos , Tipagem Molecular/tendências , Técnicas de Amplificação de Ácido Nucleico/métodos , Técnicas de Amplificação de Ácido Nucleico/tendências , SARS-CoV-2/genética , Virologia/métodos , Virologia/tendências , Viroses/classificação , Viroses/diagnóstico , Viroses/virologia
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