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1.
PLoS Pathog ; 16(8): e1008845, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32866210

RESUMO

Modified vaccinia virus Ankara (MVA) is an approved smallpox vaccine and a promising vaccine vector for other pathogens as well as for cancer therapeutics with more than 200 current or completed clinical trials. MVA was derived by passaging the parental Ankara vaccine virus hundreds of times in chick embryo fibroblasts during which it lost the ability to replicate in human and most other mammalian cells. Although this replication deficiency is an important safety feature, the genetic basis of the host restriction is not understood. Here, an unbiased human genome-wide RNAi screen in human A549 cells revealed that the zinc-finger antiviral protein (ZAP), previously shown to inhibit certain RNA viruses, is a host restriction factor for MVA, a DNA virus. Additional studies demonstrated enhanced MVA replication in several human cell lines following knockdown of ZAP. Furthermore, CRISPR-Cas9 knockout of ZAP in human A549 cells increased MVA replication and spread by more than one log but had no effect on a non-attenuated strain of vaccinia virus. The intact viral C16 protein, which had been disrupted in MVA, antagonized ZAP by binding and sequestering the protein in cytoplasmic punctate structures. Studies aimed at exploring the mechanism by which ZAP restricts MVA replication in the absence of C16 showed that knockout of ZAP had no discernible effect on viral DNA or individual mRNA or protein species as determined by droplet digital polymerase chain reaction, deep RNA sequencing and mass spectrometry, respectively. Instead, inactivation of ZAP reduced the number of aberrant, dense, spherical particles that typically form in MVA-infected human cells, suggesting that ZAP has a novel role in interfering with a late step in the assembly of infectious MVA virions in the absence of the C16 protein.


Assuntos
Proteínas de Ligação a RNA/metabolismo , Proteínas Repressoras/metabolismo , Vírus Vaccinia/fisiologia , Replicação Viral/fisiologia , Células A549 , Animais , Galinhas , Citoplasma/metabolismo , Citoplasma/virologia , DNA Viral/genética , DNA Viral/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Camundongos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Viral/genética , RNA Viral/metabolismo , Proteínas de Ligação a RNA/genética , RNA-Seq , Proteínas Repressoras/genética
2.
Mem Inst Oswaldo Cruz ; 115: e200006, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32997000

RESUMO

BACKGROUND: Occult hepatitis B virus (HBV) - characterized by the absence of detectable HBsAg in the presence of HBV DNA - represents a potential threat for blood safety. OBJECTIVES: This study was conducted with the aim to investigate the serological and molecular characterization of occult HBV infection (OBI) among blood donors in Mozambique. METHODS: 1,502 blood donors were tested for HBsAg. All HBsAg-negative individuals were tested for HBV DNA. Antibodies against HBV core, surface and HBe antigen (anti-HBc, anti-HBs, HBeAg) were measured in HBV DNA positive individuals. FINDINGS: 1435 serum samples were HBsAg negative and 16 positive for HBV DNA, 14 confirmed to have OBI, corresponding to a frequency of 0.98%. Of the 14 OBI infections identified, 13/14 (92.8%) were positive for anti-HBc, 4/14 (28.5%) for anti-HBs, and no samples were reactive for HBeAg. Of the 14 OBI cases, nine samples (64.2%) were sequenced for the S/P region. Eight samples (88.9%) belonged to genotype A1 and one (11.1%) to genotype E. One escape mutation (T123A) associated with OBI and various amino acid substitutions for genotype A1 and E were observed. MAIN CONCLUSIONS: Our results show the importance of using nucleic acid amplification test to detect occult hepatitis B infection in blood donors in Mozambique.


Assuntos
Doadores de Sangue , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/genética , Vírus da Hepatite B/isolamento & purificação , Hepatite B/diagnóstico , Técnicas de Amplificação de Ácido Nucleico/métodos , Adulto , Estudos Transversais , DNA Viral , Feminino , Humanos , Masculino , Moçambique , Filogenia , Reação em Cadeia da Polimerase
3.
PLoS One ; 15(9): e0238614, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32936826

RESUMO

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and associated with severe respiratory illness emerged in Wuhan, China, in late 2019. The virus has been able to spread promptly across all continents in the world. The current pandemic has posed a great threat to public health concern and safety. Currently, there are no specific treatments or licensed vaccines available for COVID-19. We isolated SARS-CoV-2 from the nasopharyngeal sample of a patient in Turkey with confirmed COVID-19. We determined that the Vero E6 and MA-104 cell lines are suitable for supporting SARS-CoV-2 that supports viral replication, development of cytopathic effect (CPE) and subsequent cell death. Phylogenetic analyses of the whole genome sequences showed that the hCoV-19/Turkey/ERAGEM-001/2020 strain clustered with the strains primarily from Australia, Canada, England, Iran and Kuwait and that the cases in the nearby clusters were reported to have travel history to Iran and to share the common unique nucleotide substitutions.


Assuntos
Betacoronavirus/isolamento & purificação , Pandemias , Cultura de Vírus/métodos , Animais , Austrália , Betacoronavirus/genética , Betacoronavirus/fisiologia , Canadá , Linhagem Celular , Chlorocebus aethiops , Busca de Comunicante , Infecções por Coronavirus , Efeito Citopatogênico Viral , DNA Complementar/genética , DNA Viral/genética , Inglaterra , Genoma Viral , Células HeLa , Humanos , Irã (Geográfico) , Kuweit , Macaca mulatta , Nasofaringe/virologia , Filogenia , Pneumonia Viral , Análise de Sequência de DNA , Viagem , Turquia/epidemiologia , Células Vero , Replicação Viral
4.
Medicine (Baltimore) ; 99(36): e22079, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32899080

RESUMO

RATIONALE: Parvovirus B19 has been linked to polyarteritis nodosa (PAN), but there is some controversy about its pathogenesis regarding whether it is triggered by the immune complex or by the activated immune cells that phagocytose viruses. PATIENT CONCERNS: A 38-year-old woman was admitted with fever and bicytopenia. She also complained of a painful palpable nodule in the left forearm. DIAGNOSIS: Her bone marrow aspirate revealed erythroblasts in abnormal megaloblastic changes, some of which presented with pseudopods, and parvovirus B19 was positive in a PCR analysis of her blood, which was compatible with parvovirus B19-induced hemophagocytic syndrome. Skin excisional biopsy of the nodule on the left forearm revealed a heavy inflammatory cell infiltrate throughout whole layers of a medium-sized vessel, the characteristic feature of PAN. PCR analysis of the vasculitis tissue showed a positive result for parvovirus B19. INTERVENTIONS: Her symptoms spontaneously resolved with supportive care. OUTCOMES: She underwent regular follow-up without recurrence of vasculitis-associated symptoms. LESSONS: This case highlights the presence of parvovirus B19 DNA in vasculitis tissues, which can support the role of cellular immune response in the pathogenesis of parvovirus-associated PAN.


Assuntos
Linfo-Histiocitose Hemofagocítica/complicações , Linfo-Histiocitose Hemofagocítica/virologia , Infecções por Parvoviridae/complicações , Poliarterite Nodosa/complicações , Poliarterite Nodosa/virologia , Adulto , DNA Viral , Feminino , Humanos , Parvovirus B19 Humano
5.
Nat Commun ; 11(1): 4506, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32908149

RESUMO

Bacteriophages play critical roles in the biosphere, but their vast genomic diversity has obscured their evolutionary origins, and phylogenetic analyses have traditionally been hindered by their lack of universal phylogenetic marker genes. In this study we mine metagenomic data and identify a clade of Caudovirales that encodes the ß and ß' subunits of multi-subunit RNA polymerase (RNAP), a high-resolution phylogenetic marker which enables detailed evolutionary analyses. Our RNAP phylogeny revealed that the Caudovirales RNAP forms a clade distinct from cellular homologs, suggesting an ancient acquisition of this enzyme. Within these multimeric RNAP-encoding Caudovirales (mReC), we find that the similarity of major capsid proteins and terminase large subunits further suggests they form a distinct clade with common evolutionary origin. Our study characterizes a clade of RNAP-encoding Caudovirales and suggests the ancient origin of this enzyme in this group, underscoring the important role of viruses in the early evolution of life on Earth.


Assuntos
Evolução Biológica , Caudovirales/genética , RNA Polimerases Dirigidas por DNA/genética , Subunidades Proteicas/genética , Proteínas Virais/genética , DNA Viral/genética , Conjuntos de Dados como Assunto , Transferência Genética Horizontal , Metagenômica , Filogenia , Análise de Sequência de DNA
6.
Z Gastroenterol ; 58(9): 868-871, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32947632

RESUMO

BACKGROUND: Concurrent cytomegalovirus (CMV) in inflammatory bowel disease (IBD)-related colitis is an important scenario associated with high rates of colectomy and other morbidity. Due to the low incidence of CMV, testing of all patients is associated with an unacceptably high consumption of resources and delay in treatment. Therefore, several predictive scores have been developed to identify patients at risk for a CMV infection. METHODS: We performed a retrospective single center study in a German University hospital including all IBD patients with available data on CMV-PCR analysis in whole blood between 2010 and 2018 and evaluated 2 prognostic scores for CMV infection for their diagnostic accuracy. RESULTS: In the study, 907 patients with IBD and CMV-PCR were identified. Of them, 21 patients (2.3 %) had a positive CMV-PCR (≥ 1000 copies/mL), 14 of them in ulcerative colitis and 7 in Crohn's disease. The Berlin Score identified 667 patients (73.1 %) as potentially CMV-positive, resulting in a positive predictive value of 2.5 % and a negative predictive value of 98.3 %. In contrast, the Münster Score identified 60 patients as potentially CMV-positive, resulting in a PPV of 20 % and an NPV of 99.4 %. CONCLUSIONS: Scoring systems can help to identify patients at risk for a CMV infection and minimize resource consumption and delay in treatment. Due to low incidence, a 2-step-algorithm, consisting of the Münster Score followed by a CMV-PCR if the score indicates a CMV infection, is preferable.


Assuntos
Infecções por Citomegalovirus/complicações , Infecções por Citomegalovirus/diagnóstico , Citomegalovirus/isolamento & purificação , Doenças Inflamatórias Intestinais/complicações , Infecções Oportunistas/complicações , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Colite Ulcerativa , Citomegalovirus/genética , Infecções por Citomegalovirus/sangue , DNA Viral/análise , Feminino , Humanos , Doenças Inflamatórias Intestinais/patologia , Masculino , Pessoa de Meia-Idade , Infecções Oportunistas/sangue , Infecções Oportunistas/patologia , Reação em Cadeia da Polimerase , Valor Preditivo dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
7.
BMJ ; 370: m2200, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32873599

RESUMO

Hepatitis B virus (HBV) infection causes chronic hepatitis and has long term complications. Individuals ever infected with HBV are at risk of viral reactivation under certain circumstances. This review summarizes studies on HBV persistence and reactivation with a focus on the definitions and mechanisms. Emphasis is placed on the interplay between HBV replication and host immunity as this interplay determines the patterns of persistence following viral acquisition. Chronic infections exhibit as overt persistence when a defective immune response fails to control the viral replication. The HBV genome persists despite an immune response in the form of covalently closed circular DNA (cccDNA) and integrated DNA, rendering an occult state of viral persistence in individuals whose infection appears to have been resolved. We have described HBV reactivation that occurs because of changes in the virus or the immune system. This review aims to raise the awareness of HBV reactivation and to understand how HBV persists, and discusses the risks of HBV reactivation in a variety of clinical settings.


Assuntos
Vírus da Hepatite B/imunologia , Hepatite B Crônica/virologia , Replicação Viral/imunologia , Animais , DNA Viral/sangue , Saúde Global , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/imunologia , Humanos , Imunossupressão , Imunossupressores/uso terapêutico , Fatores de Risco
8.
Nephrol Dial Transplant ; 35(8): 1338-1411, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32871594

RESUMO

BACKGROUND: There are only scarce data regarding the presentation, incidence, severity and outcomes of coronavirus disease 2019 (COVID-19) in patients undergoing long-term haemodialysis (HD). A prospective observational study was conducted in eight HD facilities in Alsace, France, to identify clinical characteristics of HD patients with COVID-19 and to assess the determinants of the risk of death. METHODS: All HD patients tested positive for COVID-19 from 5 March to 28 April 2020 were included. Collected data included patient characteristics, clinical features at diagnosis, laboratory data, treatments and outcomes. RESULTS: Among 1346 HD patients, 123 tested positive for COVID-19. Patients had a median age of 77 years (interquartile range 66-83), with a high number of comorbidities (3.2 ± 1.6 per patient). Symptoms were compatible in 63% of patients. Asthenia (77%), diarrhoea (34%) and anorexia (32%) were frequent at diagnosis. The delay between the onset of symptoms and diagnosis, death or complete recovery was 2 (0-5), 7 (4-11) and 32 (26.5-35) days, respectively. Treatment, including lopinavir/ritonavir, hydroxychloroquine and corticosteroids, was administered in 23% of patients. The median C-reactive protein (CRP) and lymphocyte count at diagnosis was 55 mg/L (IQR 25-106) and 690 Ly/µL (IQR 450-960), respectively. The case fatality rate was 24% and determinants associated with the risk of death were body temperature {hazard ratio [HR] 1.96 [95% confidence interval (CI) 1.11-3.44]; P = 0.02} and CRP at diagnosis [HR 1.01 (95% CI 1.005-1.017); P < 0.0001]. CONCLUSIONS: HD patients were found to be at high risk of developing COVID-19 and exhibited a high rate of mortality. While patients presented severe forms of the disease, they often displayed atypical symptoms, with the CRP level being highly associated with the risk of death.


Assuntos
Betacoronavirus/genética , Proteína C-Reativa/metabolismo , Infecções por Coronavirus/epidemiologia , DNA Viral/análise , Falência Renal Crônica/epidemiologia , Pneumonia Viral/epidemiologia , Diálise Renal/métodos , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Comorbidade , Infecções por Coronavirus/sangue , Feminino , França/epidemiologia , Humanos , Falência Renal Crônica/sangue , Falência Renal Crônica/terapia , Masculino , Pandemias , Pneumonia Viral/sangue , Estudos Prospectivos , Taxa de Sobrevida/tendências
9.
Arch Virol ; 165(10): 2355-2359, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32748178

RESUMO

Two Staphylococcus aureus bacteriophages, KSAP7 and KSAP11, were isolated from sewage and characterized. Based on morphology and DNA sequences, they were assigned to the genus Silviavirus, subfamily Twortvirinae, family Herelleviridae, whose members are hypothesized to be suitable for bacteriophage therapy. The KSAP7 and KSAP11 genomes were 137,950 and 138,307 bp in size, respectively. Although their DNA sequences were almost identical, evidence of site-specific DNA rearrangements was found in two regions. Changes in the number of PIEPEK amino acid sequence repeats encoded by orf10 and the insertion/deletion of a 541-bp sequence that includes a possible tail-related gene were identified.


Assuntos
Caudovirales/genética , DNA Viral/genética , Genoma Viral , Filogenia , Fagos de Staphylococcus/genética , Staphylococcus aureus/virologia , Sequência de Aminoácidos , Caudovirales/classificação , Caudovirales/isolamento & purificação , Rearranjo Gênico , Tamanho do Genoma , Mutação INDEL , Japão , Fases de Leitura Aberta , Terapia por Fagos , Alinhamento de Sequência , Fagos de Staphylococcus/classificação , Fagos de Staphylococcus/isolamento & purificação
10.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(4): 1386-1390, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32798431

RESUMO

OBJECTIVE: To explore the reasons causing the false positive of HBsAg single-ELISA-reactive in blood donors of Jiangsu province so as to provide reference data for the return of blood donors. METHODS: Serological test: HBsAg ELISA parallel detection was performed on 319 444 samples of blood donors from 2014 to 2017; the ECLIA was employed to confirm the single-ELISA-reactive (S/CO≥0.5) samples, the nucleic acid test was used to detect the HBV DNA on the all single-ELISA-reactive samples in 6/8 people mixed/single. Reagent evaluation: the Receiver-Operating-Characteristic curve (ROCC) was drawn by the ECLIA/NAT results as the gold standard, and the diagnostic performance of reagents A and B under different cut-off was evaluated. RESULTS: A total of 227 (0.71‰) single-ELISA-reactive samples were detected among 319 444 blood donors, including 39 cases (17.2%) of positive HBsAg and 12 cases (5.3%) of positive HBV DNA; Under the maximum YI, the COI (1.0) employed by the manufacturer recommendation has a better diagnostic value than laboratory COI (0.5), and the capability of reagent A was better than that of reagent B (AUC: 0.661 vs 0.632; Youden: 0.329 vs 0.297), but the specificity of both reagents was restricted (<60%). Under the maximum YI, the best cut-off value of reagents A and B were 2.4 and 1.4 COI, respectively. Compared with the cut-off value of manufacturer, the sensitivity of reagents A decreased by 33% and the false positive rate decreased by 60% while the sensitivity of reagent B increased by 140% and the false positive rate increased by 36%, respectively. CONCLUSION: The false positive of HBsAg single-ELISA-reactive in blood donors is caused by the limited specificity of ELISA reagent and the setting of COI values. According to ROCC maximum YI method, the COI can be set as 2.4 COI and (0.5-1.4) COI for reagent A and B to reduce false positive rate.


Assuntos
Antígenos de Superfície da Hepatite B , Hepatite B , Doadores de Sangue , DNA Viral , Ensaio de Imunoadsorção Enzimática , Vírus da Hepatite B , Humanos , Sensibilidade e Especificidade
11.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(4): 1391-1396, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32798432

RESUMO

OBJECTIVE: To analyze the reentry situation of HBsAg single reagent reactive blood donors in Anhui province, and to verify the rationality and effectiveness of reentry strategy of blood donors in Anhui province. METHODS: Shielded blood donors who were HBsAg single reagent reactive might voluntarily apply for returning to the team of blood donors after the shield of 6 months. Blood bankstaff that shielded those donors should draw blood and conduct screening tests. Samples from donors who were HBsAg negative should be delivered to Anhui Blood Center to conduct the reentry detections. Shielded blood donors were allowed to return to the team if the results of HBsAg test, neutralization test, HBcAb test and nucleic acid test were negative. RESULTS: 109 person-portions of samples for returning to team from September 2013 to December 2016 were delivered to Anhui Blood Center. After reentry tests, 60 of them were negative, 8 cases were positive, while 41 cases were undetermined, and the qualified rate was 55.05%.25 negative donors were from Hefei, 20 of them donated blood again and were negative. CONCLUSION: The shielding and reentry strategy of blood donors with HBsAg single reagent reactive in Anhui province is rational and effective. However, there are still some deficiencies in trace of donors and information transmission, which needs to be further improved.


Assuntos
Antígenos de Superfície da Hepatite B , Hepatite B , Doadores de Sangue , DNA Viral , Vírus da Hepatite B , Humanos
12.
PLoS Pathog ; 16(8): e1008752, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32760121

RESUMO

Members of the family of pyrin and HIN domain containing (PYHIN) proteins play an emerging role in innate immunity. While absent in melanoma 2 (AIM2) acts a cytosolic sensor of non-self DNA and plays a key role in inflammasome assembly, the γ-interferon-inducible protein 16 (IFI16) restricts retroviral gene expression by sequestering the transcription factor Sp1. Here, we show that the remaining two human PYHIN proteins, i.e. myeloid cell nuclear differentiation antigen (MNDA) and pyrin and HIN domain family member 1 (PYHIN1 or IFIX) share this antiretroviral function of IFI16. On average, knock-down of each of these three nuclear PYHIN proteins increased infectious HIV-1 yield from human macrophages by more than an order of magnitude. Similarly, knock-down of IFI16 strongly increased virus transcription and production in primary CD4+ T cells. The N-terminal pyrin domain (PYD) plus linker region containing a nuclear localization signal (NLS) were generally required and sufficient for Sp1 sequestration and anti-HIV-1 activity of IFI16, MNDA and PYHIN1. Replacement of the linker region of AIM2 by the NLS-containing linker of IFI16 resulted in a predominantly nuclear localization and conferred direct antiviral activity to AIM2 while attenuating its ability to form inflammasomes. The reverse change caused nuclear-to-cytoplasmic relocalization of IFI16 and impaired its antiretroviral activity but did not result in inflammasome assembly. We further show that the Zn-finger domain of Sp1 is critical for the interaction with IFI16 supporting that pyrin domains compete with DNA for Sp1 binding. Finally, we found that human PYHIN proteins also inhibit Hepatitis B virus and simian vacuolating virus 40 as well as the LINE-1 retrotransposon. Altogether, our data show that IFI16, PYHIN1 and MNDA restrict HIV-1 and other viral pathogens by interfering with Sp1-dependent gene expression and support an important role of nuclear PYHIN proteins in innate antiviral immunity.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Núcleo Celular/metabolismo , Infecções por HIV/prevenção & controle , HIV-1/imunologia , Macrófagos/imunologia , Proteínas Nucleares/metabolismo , Fator de Transcrição Sp1/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/virologia , Núcleo Celular/genética , DNA Viral/genética , Células HEK293 , Infecções por HIV/imunologia , Infecções por HIV/patologia , Infecções por HIV/virologia , HIV-1/genética , HIV-1/isolamento & purificação , Células Hep G2 , Humanos , Imunidade Inata/imunologia , Inflamassomos/genética , Inflamassomos/imunologia , Macrófagos/metabolismo , Macrófagos/virologia , Proteínas Nucleares/genética , Fator de Transcrição Sp1/genética , Replicação Viral
13.
Medicine (Baltimore) ; 99(32): e21570, 2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32769902

RESUMO

RATIONALE: Macrophage activation syndrome (MAS) is a rare life-threatening condition characterized by cytokine-mediated tissue injury and multiorgan dysfunction. PATIENT CONCERNS: We describe the unique case of young man who developed MAS as the sole manifestation of an otherwise paucisymptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. DIAGNOSES: Clinical and biological criteria led to the diagnosis of MAS; cytokine profile was highly suggestive reverse transcription polymerase chain reaction for SARS-CoV-2 in nasopharyngeal swabs was negative, but serum anti-SARS-CoV-2 immunoglobulin A and immunoglobulin G resulted positive leading to the diagnosis of SARS-CoV-2 infection. INTERVENTIONS: The patient was treated with empiric antibiotic and hydroxychloroquine. OUTCOMES: Clinical improvement ensued. At follow-up, the patient is well. LESSON: SARS-CoV-2 infection may trigger develop life-threatening complications, like MAS. This can be independent from coronavirus disease 2019 gravity.


Assuntos
Ceftriaxona/administração & dosagem , Infecções por Coronavirus/diagnóstico , Hospitalização , Hidroxicloroquina/administração & dosagem , Síndrome de Ativação Macrofágica/diagnóstico , Pneumonia Viral/diagnóstico , Adolescente , Análise Química do Sangue , China , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/tratamento farmacológico , DNA Viral/análise , Diagnóstico Diferencial , Progressão da Doença , Quimioterapia Combinada , Eletrocardiografia/métodos , Seguimentos , Humanos , Síndrome de Ativação Macrofágica/terapia , Masculino , Pandemias , Alta do Paciente , Pneumonia Viral/tratamento farmacológico , Radiografia Torácica/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Medição de Risco , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento
14.
Dan Med J ; 67(9)2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32800072

RESUMO

INTRODUCTION: As the coronavirus disease 2019 (COVID-19) epidemic evolves and test strategies change, understanding the concepts of testing (gold standard and test performance measures) becomes essential. The challenge of any novel disease is that the gold standard has yet to be defined. METHODS: We reanalysed published data on real-time reverse transcription quantitative polymerase chain reaction (RT-qPCR) of severe acute respiratory syndrome coronavirus-2 to illustrate how predictive values vary with disease prevalence, sensitivity (set to values between 30% and 95%) and specificity (set to 99% or 99.98%). We used published data on chest CT and RT-qPCR to examine the potential of latent class analysis to estimate the sensitivity and specificity of RT-qPCR when no single gold standard exists. RESULTS: For the various sensitivity values, the negative predictive value of a RT-qPCR test remained above 92% until a COVID-19 prevalence of > 10%. The positive predictive value (PPV) was more variable. For a sensitivity of 95% and a specificity of 99%, the PPV was less-than 10% at a prevalence of 0.1%, increasing to about 90% at a prevalence of 10%. This improved to a PPV of 85% and almost 100%, respectively, when specificity increased to 99.98%. In a restricted latent class analysis, the sensitivity was 97.1% and the specificity was 99.9%, which is similar to figures from the Danish Health Authority. However, derived predictive values depended on model specification. CONCLUSIONS: A high risk of false-positives should be considered when extending the testing strategy, whereas false-negatives may occur during local outbreaks. This may have consequences for, e.g., containment strategies and research. A confirmatory test (e.g., demonstrating seroconversion or repeated RT-qPCR) may be warranted. FUNDING: none. TRIAL REGISTRATION: not relevant.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/diagnóstico , DNA Viral/análise , Publicações Periódicas como Assunto , Pneumonia Viral/diagnóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Infecções por Coronavirus/virologia , Reações Falso-Negativas , Humanos , Pandemias , Pneumonia Viral/virologia
15.
Invest Ophthalmol Vis Sci ; 61(10): 29, 2020 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-32797198

RESUMO

Purpose: This systematic review aimed to determine currently reported clinical and prodromal ocular symptoms in patients with coronavirus disease 2019 (COVID-19). Methods: An online article search was performed in PubMed and EMBASE. Altogether 15 studies (retrospective, prospective, or case studies) involving 1533 patients with COVID-19, reporting on ocular symptoms, and with outcome data available were identified. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses reporting guidelines were followed. Study-specific estimates (incidence rates of ocular symptoms in patients with COVID-19) of cases were combined using one-group meta-analysis in a random-effects model. Results: Of all included studies, 11.2% (95% confidence interval, 5.5-16.9; 78/1526 cases) reported ocular symptoms. The most common ocular finding was conjunctivitis. Prodromal ocular symptoms occurred in 12.5% (13/104 cases) of patients with COVID-19. Positive real-time polymerase chain reaction results were obtained for 16.7% (10/60 cases) of conjunctival samples and 0% (0/17 cases) of tear samples. Twelve ocular conjunctival swab samples tested positive for SARS-CoV-2. Ten cases were from subjects showing ocular symptoms (16.7%, 10/60 cases), and the remaining two cases were from subjects without ocular manifestation (1.8%, 2/113 cases). Limitations included the short study period, small sample size, findings were limited to the Asian population, only seven articles included ophthalmologic examination details, and there is currently no consensus on COVID-19 management. Conclusions: Ocular symptoms may occur in the presymptomatic phase as a prodromal symptom (12.5%, 13/104 cases), suggesting the possibility of viral transmission from the conjunctiva.


Assuntos
Conjuntivite Viral/epidemiologia , Infecções por Coronavirus/epidemiologia , Pandemias/estatística & dados numéricos , Pneumonia Viral/epidemiologia , Sintomas Prodrômicos , Síndrome Respiratória Aguda Grave/diagnóstico , Técnicas de Laboratório Clínico/métodos , Conjuntivite Viral/diagnóstico , Infecções por Coronavirus/diagnóstico , DNA Viral/análise , Progressão da Doença , Feminino , Humanos , Incidência , Masculino , Pandemias/prevenção & controle , Pneumonia Viral/diagnóstico , Prognóstico , Reação em Cadeia da Polimerase em Tempo Real/métodos , Medição de Risco , Síndrome Respiratória Aguda Grave/epidemiologia
16.
PLoS One ; 15(8): e0237418, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32790779

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic has crudely demonstrated the need for massive and rapid diagnostics. By the first week of July, more than 10,000,000 positive cases of COVID-19 have been reported worldwide, although this number could be greatly underestimated. In the case of an epidemic emergency, the first line of response should be based on commercially available and validated resources. Here, we demonstrate the use of the miniPCR, a commercial compact and portable PCR device recently available on the market, in combination with a commercial well-plate reader as a diagnostic system for detecting genetic material of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causal agent of COVID-19. We used the miniPCR to detect and amplify SARS-CoV-2 DNA sequences using the sets of initiators recommended by the World Health Organization (WHO) for targeting three different regions that encode for the N protein. Prior to amplification, samples were combined with a DNA intercalating reagent (i.e., EvaGreen Dye). Sample fluorescence after amplification was then read using a commercial 96-well plate reader. This straightforward method allows the detection and amplification of SARS-CoV-2 nucleic acids in the range of ~625 to 2×105 DNA copies. The accuracy and simplicity of this diagnostics strategy may provide a cost-efficient and reliable alternative for COVID-19 pandemic testing, particularly in underdeveloped regions where RT-QPCR instrument availability may be limited. The portability, ease of use, and reproducibility of the miniPCR makes it a reliable alternative for deployment in point-of-care SARS-CoV-2 detection efforts during pandemics.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Sistemas Automatizados de Assistência Junto ao Leito , Reação em Cadeia da Polimerase/instrumentação , Reação em Cadeia da Polimerase/métodos , Sequência de Bases , Betacoronavirus/química , Infecções por Coronavirus/virologia , DNA Viral/genética , Confiabilidade dos Dados , Humanos , Proteínas do Nucleocapsídeo/genética , Pandemias , Pneumonia Viral/virologia , Reação em Cadeia da Polimerase/economia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
BMC Infect Dis ; 20(1): 600, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32795251

RESUMO

BACKGROUND: BK virus-associated nephropathy (BKVAN) is a relatively common cause of renal dysfunction in the first six months after renal transplantation. It arises from reactivation of the latent and usually harmless BK virus (BK virus) due to immunosuppression and other factors including some that are unique to renal transplantation such as allograft injury. BKVAN is much rarer in non-renal solid organ transplantation, where data regarding diagnosis and management are extremely limited. CASE PRESENTATION: We report a case of a 58-year-old man found to have worsening renal dysfunction nine months after bilateral sequential lung transplantation for chronic obstructive pulmonary disease (COPD). He had required methylprednisolone for acute allograft rejection but achieved good graft function. Urine microscopy and culture and renal ultrasound were normal. BK virus PCR was positive at high levels in urine and blood. Renal biopsy subsequently confirmed BKVAN. The patient progressed to end-stage renal failure requiring haemodialysis despite reduction in immunosuppression, including switching mycophenolate for everolimus, and the administration of intravenous immunoglobulin (IVIG). CONCLUSIONS: This very rare case highlights the challenges presented by BK virus in the non-renal solid organ transplant population. Diagnosis can be difficult, especially given the heterogeneity with which BKV disease has been reported to present in such patients, and the optimal approach to management is unknown. Balancing reduction in immunosuppression against prevention of allograft rejection is delicate. Improved therapeutic options are clearly required.


Assuntos
Transplante de Pulmão , Infecções por Polyomavirus/diagnóstico , Infecções Tumorais por Vírus/diagnóstico , Vírus BK/genética , Vírus BK/isolamento & purificação , DNA Viral/metabolismo , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Imunossupressores/uso terapêutico , Transplante de Rim , Transplante de Pulmão/efeitos adversos , Masculino , Metilprednisolona/uso terapêutico , Pessoa de Meia-Idade , Ácido Micofenólico/uso terapêutico , Infecções por Polyomavirus/virologia , Doença Pulmonar Obstrutiva Crônica/terapia , Infecções Tumorais por Vírus/virologia
18.
J Hosp Med ; 15: 538-539, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32816669

RESUMO

Viral testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), particularly early in the COVID-19 pandemic, was limited by supply of reagents. We pooled nasopharyngeal samples from patients at low risk of SARS-CoV-2 infection in groups of 3 for testing. Three weeks of testing using this strategy resulted in 530 patient tests in 179 cartridges; 4 positive test groups required the use of 11 additional cartridges with an overall positive rate of 0.8% in a low-risk population. This strategy resulted in the use of 340 fewer cartridges than if each test were performed on one patient sample. Pooled testing of low-risk populations allows for continued testing even when supplies are relatively scarce.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/diagnóstico , DNA Viral/análise , Testes Genéticos/métodos , Pacientes Internados , Pandemias , Pneumonia Viral/diagnóstico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Humanos , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia
19.
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
20.
Artigo em Inglês | MEDLINE | ID: mdl-32756824

RESUMO

Human cytomegalovirus (HCMV) infections remain a neglected public health issue. The aim of the present study was to evaluate the frequency of HCMV congenital infections in newborns up to 1 month in the Sao Paulo State, from 2010 to 2018. The molecular characterization of HCMV-positive samples was also undertaken. Urine samples from 275 potential congenital HCMV-infected patients were tested by real-time Polymerase Chain Reaction (qPCR). HCMV-positive samples were amplified by conventional PCR targeting the UL89 gene, sequenced and searched for mutations. A total of 32 (11.6%) positive-HCMV cases were detected (mean Ct 30.59); mean and median age of 10.3 and 6 days old, respectively. Children aged between 0-3 weeks had higher HCMV detection rates (84.4%; 27/32). UL89 gene was successfully sequenced in two samples, both classified as the human betaherpesvirus 5. No described resistance-associated mutations were identified. A routine screening in newborns coupled with the genetic characterization of key viral genes is vital to decrease sequels associated with congenital HCMV infections.


Assuntos
Infecções por Citomegalovirus/epidemiologia , Citomegalovirus/isolamento & purificação , DNA Viral , Brasil/epidemiologia , Criança , Citomegalovirus/genética , Infecções por Citomegalovirus/diagnóstico , Humanos , Lactente , Recém-Nascido , Programas de Rastreamento , Reação em Cadeia da Polimerase em Tempo Real
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