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1.
BMC Med ; 18(1): 217, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32664866

RESUMO

BACKGROUND: Since the first cluster of cases was identified in Wuhan City, China, in December 2019, coronavirus disease 2019 (COVID-19) rapidly spreads globally. Scientists have made strides in estimating key transmission and epidemiological parameters. In particular, accumulating evidence points to a substantial fraction of asymptomatic or subclinical infections, which influences our understanding of the transmission potential and severity of this emerging disease. In this study, we derive estimates of the transmissibility and virulence of COVID-19 in Wuhan City, China, by reconstructing the underlying transmission dynamics using multiple data sources. METHODS: We employ statistical methods and publicly available epidemiological datasets to jointly derive estimates of transmissibility and severity associated with the novel coronavirus. For this purpose, the daily series of laboratory-confirmed COVID-19 cases and deaths in Wuhan City together with epidemiological data of Japanese repatriated from Wuhan City on board government-chartered flights were integrated into our analysis. RESULTS: Our posterior estimates of basic reproduction number (R) in Wuhan City, China, in 2019-2020 reached values at 3.49 (95% CrI 3.39-3.62) with a mean serial interval of 6.0 days, and the enhanced public health intervention after January 23 in 2020 was associated with a significantly reduced R at 0.84 (95% CrI 0.81-0.88), with the total number of infections (i.e., cumulative infections) estimated at 1,906,634 (95% CrI 1,373,500-2,651,124) in Wuhan City, elevating the overall proportion of infected individuals to 19.1% (95% CrI 13.5-26.6%). We also estimated the most recent crude infection fatality ratio (IFR) and time-delay adjusted IFR at 0.04% (95% CrI 0.03-0.06%) and 0.12% (95% CrI 0.08-0.17%), respectively, estimates that are substantially smaller than the crude CFR estimated at 4.06%. CONCLUSIONS: We have estimated key epidemiological parameters of the transmissibility and virulence of COVID-19 in Wuhan, China, during January-February 2020 using an ecological modeling approach that is suitable to infer epidemiological parameters with quantified uncertainty from partial observations collected by surveillance systems. Our estimate of time-delay adjusted IFR falls in the range of the median IFR estimates based on multiple serological studies conducted in several areas of the world.


Assuntos
Betacoronavirus/patogenicidade , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Número Básico de Reprodução , China/epidemiologia , Humanos , Modelos Teóricos , Pandemias , Virulência
3.
Arch Cardiovasc Dis ; 113(6-7): 443-447, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32636131

RESUMO

BACKGROUND: How coronavirus 2019 (COVID-19) is affecting management of myocardial infarction is a matter of concern, as medical resources have been massively reorientated and the population has been in lockdown since 17 March 2020 in France. AIMS: To describe how lockdown has affected the evolution of the weekly rate of myocardial infarctions (non-ST-segment and ST-segment elevation) hospital admissions in Lyon, the second largest city in France. To verify the trend observed, the same analysis was conducted for an identical time window during 2018-2019 and for an unavoidable emergency, i.e. birth. METHODS: Based on the national hospitalisation database [Programme de médicalisation des systèmes d'information (PMSI)], all patients admitted to the main public hospitals for a principal diagnosis of myocardial infarction or birth during the 2nd to the 14th week of 2020 were included. These were compared with the average number of patients admitted for the same diagnosis during the same time window in 2018 and 2019. RESULTS: Before lockdown, the number of admissions for myocardial infarction in 2020 differed from that in 2018-2019 by less than 10%; after the start of lockdown, it decreased by 31% compared to the corresponding time window in 2018-2019. Conversely, the numbers of births remained stable across years and before and after the start of lockdown. CONCLUSION: This study strongly suggests a decrease in the number of admissions for myocardial infarction during lockdown. Although we do not have a long follow-up to determine whether this trend will endure, this is an important warning for the medical community and health authorities.


Assuntos
Infecções por Coronavirus/epidemiologia , Infarto do Miocárdio sem Supradesnível do Segmento ST/terapia , Admissão do Paciente/tendências , Pneumonia Viral/epidemiologia , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Betacoronavirus/patogenicidade , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , França/epidemiologia , Humanos , Incidência , Infarto do Miocárdio sem Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio sem Supradesnível do Segmento ST/epidemiologia , Pandemias , Pneumonia Viral/diagnóstico , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , Prognóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/epidemiologia , Fatores de Tempo , Virulência
4.
Biomed Environ Sci ; 33(6): 385-395, 2020 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-32641201

RESUMO

Objective: This study aimed to evaluate the genetic diversity, virulence, and antimicrobial resistance of Aeromonas isolates from clinical patients, tap water systems, and food. Methods: Ninety Aeromonas isolates were obtained from Ma'anshan, Anhui province, China, and subjected to multi-locus sequence typing (MLST) with six housekeeping genes. Their taxonomy was investigated using concatenated gyrB-cpn60 sequences, while their resistance to 12 antibiotics was evaluated. Ten putative virulence factors and several resistance genes were identified by PCR and sequencing. Results: The 90 Aeromonas isolates were divided into 84 sequence types, 80 of which were novel, indicating high genetic diversity. The Aeromonas isolates were classified into eight different species. PCR assays identified virulence genes in the isolates, with the enterotoxin and hemolysin genes act, aerA, alt, and ast found in 47 (52.2%), 13 (14.4%), 22 (24.4%), and 12 (13.3%) of the isolates, respectively. The majority of the isolates (≥ 90%) were susceptible to aztreonam, imipenem, cefepime, chloramphenicol, gentamicin, tetracycline, and ciprofloxacin. However, several resistance genes were detected in the isolates, as well as a new mcr-3 variant. Conclusions: Sequence type, virulence properties, and antibiotic resistance vary in Aeromonas isolates from clinical patients, tap water systems, and food.


Assuntos
Aeromonas , Água Potável/microbiologia , Farmacorresistência Bacteriana , Microbiologia de Alimentos , Variação Genética , Infecções por Bactérias Gram-Negativas/microbiologia , Aeromonas/efeitos dos fármacos , Aeromonas/genética , Aeromonas/isolamento & purificação , Aeromonas/patogenicidade , Antibacterianos/farmacologia , China , Especificidade da Espécie , Virulência
5.
J Stroke Cerebrovasc Dis ; 29(8): 104941, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32689643

RESUMO

Coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a global health threat. Some COVID-19 patients have exhibited widespread neurological manifestations including stroke. Acute ischemic stroke, intracerebral hemorrhage, and cerebral venous sinus thrombosis have been reported in patients with COVID-19. COVID-19-associated coagulopathy is increasingly recognized as a result of acute infection and is likely caused by inflammation, including inflammatory cytokine storm. Recent studies suggest that axonal transport of SARS-CoV-2 to the brain can occur via the cribriform plate adjacent to the olfactory bulb that may lead to symptomatic anosmia. The internalization of SARS-CoV-2 is mediated by the binding of the spike glycoprotein of the virus to the angiotensin-converting enzyme 2 (ACE2) on cellular membranes. ACE2 is expressed in several tissues including lung alveolar cells, gastrointestinal tissue, and brain. The aim of this review is to provide insights into the clinical manifestations and pathophysiological mechanisms of stroke in COVID-19 patients. SARS-CoV-2 can down-regulate ACE2 and, in turn, overactivate the classical renin-angiotensin system (RAS) axis and decrease the activation of the alternative RAS pathway in the brain. The consequent imbalance in vasodilation, neuroinflammation, oxidative stress, and thrombotic response may contribute to the pathophysiology of stroke during SARS-CoV-2 infection.


Assuntos
Betacoronavirus/patogenicidade , Encéfalo/fisiopatologia , Infecções por Coronavirus/fisiopatologia , Encefalite Viral/fisiopatologia , Pneumonia Viral/fisiopatologia , Acidente Vascular Cerebral/fisiopatologia , Betacoronavirus/metabolismo , Coagulação Sanguínea , Encéfalo/metabolismo , Encéfalo/virologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/metabolismo , Infecções por Coronavirus/virologia , Encefalite Viral/epidemiologia , Encefalite Viral/metabolismo , Encefalite Viral/virologia , Interações entre Hospedeiro e Microrganismos , Humanos , Mediadores da Inflamação/metabolismo , Estresse Oxidativo , Pandemias , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/epidemiologia , Pneumonia Viral/metabolismo , Pneumonia Viral/virologia , Sistema Renina-Angiotensina , Transdução de Sinais , Glicoproteína da Espícula de Coronavírus/metabolismo , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/virologia , Vasodilatação , Virulência
6.
J Thorac Cardiovasc Surg ; 160(2): 447-451, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32689700

RESUMO

The COVID-19 pandemic necessitates aggressive infection mitigation strategies to reduce the risk to patients and healthcare providers. This document is intended to provide a framework for the adult cardiac surgeon to consider in this rapidly changing environment. Preoperative, intraoperative, and postoperative detailed protective measures are outlined. These are guidance recommendations during a pandemic surge to be used for all patients while local COVID-19 disease burden remains elevated.


Assuntos
Betacoronavirus/patogenicidade , Procedimentos Cirúrgicos Cardíacos/normas , Infecções por Coronavirus/prevenção & controle , Infecção Hospitalar/prevenção & controle , Cardiopatias/cirurgia , Controle de Infecções/normas , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Transmissão de Doença Infecciosa do Profissional para o Paciente/prevenção & controle , Salas Cirúrgicas/normas , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Sala de Recuperação/normas , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Consenso , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/transmissão , Infecção Hospitalar/virologia , Cardiopatias/epidemiologia , Humanos , Saúde do Trabalhador/normas , Segurança do Paciente/normas , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , Medição de Risco , Fatores de Risco , Virulência
7.
J Thorac Cardiovasc Surg ; 160(2): 452-455, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32689701

RESUMO

In the setting of the current novel coronavirus pandemic, this document has been generated to provide guiding statements for the adult cardiac surgeon to consider in a rapidly evolving national landscape. Acknowledging the risk for a potentially prolonged need for cardiac surgery procedure deferral, we have created this proposed template for physicians and interdisciplinary teams to consider in protecting their patients, institution, and their highly specialized cardiac surgery team. In addition, recommendations on the transition from traditional in-person patient assessments and outpatient follow-up are provided. Lastly, we advocate that cardiac surgeons must continue to serve as leaders, experts, and relevant members of our medical community, shifting our role as necessary in this time of need.


Assuntos
Betacoronavirus/patogenicidade , Procedimentos Cirúrgicos Cardíacos/normas , Infecções por Coronavirus/prevenção & controle , Infecção Hospitalar/prevenção & controle , Cardiopatias/cirurgia , Controle de Infecções/normas , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Transmissão de Doença Infecciosa do Profissional para o Paciente/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Triagem/normas , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Consenso , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/transmissão , Infecção Hospitalar/virologia , Cardiopatias/epidemiologia , Humanos , Saúde do Trabalhador/normas , Segurança do Paciente/normas , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , Medição de Risco , Fatores de Risco , Virulência
8.
Mar Pollut Bull ; 157: 111302, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32658670

RESUMO

Concentration of bacterial species indicative of fecal contamination in the gut of mangrove oysters (Crassostrea gasar) is a major concern for public health and food surveillance. Our work aimed to determine the occurrence, antibiotic-resistance, phylogenetic profile and virulence of Escherichia coli strains isolated from C. gasar farmed in four estuaries of Amazonia. Santo Antônio de Urindeua was the sampling point with the highest number of E. coli cells in oyster samples (104 per 100 g of sample). Twenty-four isolates (52.2%) showed resistance to cephalotin and 18 to amoxicillin (39.1%). Eighteen clonal populations were determined by rep-PCR and were mainly affiliated to the pathogenic and commensal phylo-groups B1 and D. The presence of elt genes suggests that 10 of these clones belong to the Enterotoxigenic Escherichia coli pathotype. Plasmids, mostly of the F incompatibility group, were detected in the majority of the strains. All isolates were susceptible to last-resort antibiotics.


Assuntos
Crassostrea , Escherichia coli , Animais , Antibacterianos , Brasil , Estuários , Filogenia , Virulência
9.
Proc Natl Acad Sci U S A ; 117(26): 15193-15199, 2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32522874

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) poses an immediate, major threat to public health across the globe. Here we report an in-depth molecular analysis to reconstruct the evolutionary origins of the enhanced pathogenicity of SARS-CoV-2 and other coronaviruses that are severe human pathogens. Using integrated comparative genomics and machine learning techniques, we identify key genomic features that differentiate SARS-CoV-2 and the viruses behind the two previous deadly coronavirus outbreaks, SARS-CoV and Middle East respiratory syndrome coronavirus (MERS-CoV), from less pathogenic coronaviruses. These features include enhancement of the nuclear localization signals in the nucleocapsid protein and distinct inserts in the spike glycoprotein that appear to be associated with high case fatality rate of these coronaviruses as well as the host switch from animals to humans. The identified features could be crucial contributors to coronavirus pathogenicity and possible targets for diagnostics, prognostication, and interventions.


Assuntos
Betacoronavirus/genética , Evolução Molecular , Genoma Viral , Proteínas do Nucleocapsídeo/genética , Glicoproteína da Espícula de Coronavírus/genética , Animais , Betacoronavirus/classificação , Betacoronavirus/patogenicidade , Especificidade de Hospedeiro , Humanos , Aprendizado de Máquina , Coronavírus da Síndrome Respiratória do Oriente Médio/classificação , Coronavírus da Síndrome Respiratória do Oriente Médio/genética , Coronavírus da Síndrome Respiratória do Oriente Médio/patogenicidade , Mutagênese Insercional , Sinais de Localização Nuclear/genética , Proteínas do Nucleocapsídeo/química , Filogenia , Homologia de Sequência , Glicoproteína da Espícula de Coronavírus/química , Virulência/genética
10.
J Thorac Cardiovasc Surg ; 160(2): 522-528, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32507689
13.
Plant Dis ; 104(8): 2111-2122, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32539592

RESUMO

The soybean cyst nematode (SCN), Heterodera glycines, is the most damaging pathogen of soybean. Use of resistant cultivars is an effective strategy to manage SCN, but it also selects for virulent populations over time. A 12-year field experiment was initiated in 2003 to study how tillage and 11 different sequences of four cultivars impact SCN population dynamics and virulence. An SCN-susceptible cultivar and three resistant cultivars (R1, R2, and R3 derived from cultivars PI 88788, Peking, and PI 437654, respectively) were used. Tillage had minimal effect on SCN population density. Compared with no till, conventional tillage resulted in a faster increase of SCN virulence to Peking when the SCN was selected by R2 and virulence to PI 88788 by R3. Among the three SCN-resistant cultivars, R1 supported the greatest population density, R2 supported intermediate population density, and R3 supported the least SCN population density. The SCN populations selected by R1 overcame the resistance in PI 88788 but not in Peking and PI 437654. R2 selected SCN populations that overcame the resistance in Peking but not in PI 88788 and PI 437654. In contrast, R3 selected SCN populations that overcame both PI 88788 and Peking sources of resistance. There was no increase of virulence to PI 437654 in any cultivar sequence. R1 in rotation with R2 or R3 had a negative effect on female index on Peking. Susceptible soybean reduced SCN virulence to Peking, indicating that there was fitness cost of the Peking virulent SCN type. These results suggest that rotation of Peking with PI 88788 is a good strategy for managing the SCN, and susceptible cultivar and no till may reduce SCN virulence selection pressure in some rotations.[Formula: see text] Copyright © 2020 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Cistos , Soja , Animais , Fenótipo , Doenças das Plantas , Densidade Demográfica , Virulência
14.
Plant Dis ; 104(8): 2095-2101, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32544001

RESUMO

Wheat leaf rust, caused by Puccinia triticina, is a common fungal disease of wheat in China. In order to identify races and determine the individual virulence of isolates in different wheat-growing regions in China, leaf rust samples collected from 18 provinces in 2011 to 2013 were tested on 37 Thatcher near-isogenic lines each carrying a different single leaf rust resistance gene. A total of 158 races were identified. Races THTT (19.5%), THTS (16.9%), PHTT (7.7%), THJS (5.0%), THJT (4.2%), and PHTS (4.0%) were the most predominant races in 2011 to 2013. All of these races were avirulent to resistance genes Lr9 and Lr24. The two most frequent races, THTT and THTS, were widely distributed. The frequencies of the isolates with virulence to Lr1, Lr2c, Lr3, Lr16, Lr26, Lr17, LrB, Lr10, Lr14a, Lr3bg, Lr14b, Lr33, Lr37, and Lr50 exceeded 90%. Frequencies of virulence to Lr2a, Lr3ka, Lr11, Lr30, Lr2b, and Lr32 exceeded 70% but were less than 90%. Frequencies of virulence to Lr18, Lr21, Lr15, Lr23, Lr33+34, Lr36, Lr39, and Lr44 were below 70%, whereas the frequency of virulence to Lr25 was less than 1%. All isolates were avirulent to Lr9, Lr19, Lr24, Lr28, Lr42, Lr29, Lr38, and Lr47. The identified races and individual virulence frequencies provide a basis for selection of effective leaf rust resistance genes for use in breeding programs and can also provide information for the study of race evolution of P. triticina.


Assuntos
Basidiomycota , Doenças das Plantas , China , Triticum , Virulência
15.
Plant Dis ; 104(8): 2233-2241, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32552282

RESUMO

Extensive mortality of Metrosideros polymorpha (`ohi`a) trees has been associated with Ceratocystis spp. on Hawai`i Island and was named rapid `ohi`a death (ROD). Both C. lukuohia and C. huliohia have been associated with ROD, although C. lukuohia appears to be the more important pathogen. Crown observations and dissections of forest trees either wound-inoculated with, or naturally infected by, C. lukuohia were conducted to confirm pathogenicity and document patterns of host colonization. In pathogenicity trials, one of three and two of three trees inoculated with the fungus in February and August, respectively, exhibited crown wilt symptoms at 92 and 69 days after inoculation. Extensive, radial, black staining of the sapwood was found in main stems, while no crown wilt or xylem staining was found in control trees. Xylem staining, necrotic phloem, and fungus presence was noted in six trees inoculated in May to June and harvested 37 to 42 days later, and these observations were compared with those in two naturally infected trees felled in early August. Contiguous xylem staining was found in the main stems and into crowns of all diseased trees, while discontinuous streaks of xylem staining extended into the main forks and side branches. Necrotic phloem associated with xylem staining occurred on the lower stems of inoculated trees. Aside from the necrotic phloem and radial staining of the sapwood, symptom development in `ohi`a infected with C. lukuohia is similar to other systemic wilt diseases on hardwood trees. We propose Ceratocystis wilt of `ohi`a as the official name of the disease.


Assuntos
Ascomicetos , Floema , Árvores , Virulência , Xilema
16.
Int J Infect Dis ; 97: 290-292, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32553720

RESUMO

A relationship between the infecting dose and the risk of disease severity has not been demonstrated for SARS-CoV-2 infection. Here, we report three clusters of individuals that were potentially exposed to distinct inoculum in Madrid. Overall each group developed divergent clinical forms of COVID-19. Our data support that a greater viral inoculum at the time of SARS-CoV-2 exposure might determine a higher risk of severe COVID-19.


Assuntos
Infecções por Coronavirus/transmissão , Pneumonia Viral/transmissão , Carga Viral , Adulto , Idoso , Idoso de 80 Anos ou mais , Betacoronavirus , Infecções por Coronavirus/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/epidemiologia , Espanha/epidemiologia , Fatores de Tempo , Virulência
17.
Plant Dis ; 104(8): 2242-2251, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32568629

RESUMO

Recently, the incidence of Myrothecium leaf spot, a foliar disease of watermelon, has increased in South Carolina. However, the identity of the fungal species responsible for outbreaks of this disease has not been determined. Sequence data from four partial gene regions were used to conduct Bayesian inference in order to identify 95 isolates of Stachybotriaceae. Isolates were collected in South Carolina between July 2015 and May 2018. In total, six species of Stachybotriaceae were identified on watermelon and two other cucurbits: Albifimbria verrucaria, Gregatothecium humicola, Paramyrothecium foliicola, P. humicola, Xenomyrothecium tongaense, and Xepicula leucotricha. Two species, G. humicola and P. foliicola, were the predominant species found. Within these two species, genetic differences within small spatial scales were detected. Five species (all except Xenomyrothecium tongaense) were tested in experiments to determine their pathogenicity and relative virulence on three hosts grown in rotation in South Carolina. Southern pea plants were less susceptible than watermelon and tomato plants, which were equally susceptible. This constitutes the first reliable report of pathogenicity of any of the five tested species of Stachybotriaceae on these three vegetable crops. Another important finding was that none of the isolates were identified as P. roridum, the species considered to be the only causal agent of Myrothecium leaf spot on cucurbits. We propose the common name "ink spot" for the foliar phase of diseases caused by genera within the family Stachybotriaceae. This name is descriptive and likely to be accepted by growers. To prevent further loss incurred by ink spot, watermelon and tomato crops should be monitored for this disease.


Assuntos
Tinta , Doenças das Plantas , Teorema de Bayes , Variação Genética , South Carolina , Virulência
18.
Plant Dis ; 104(8): 2275-2287, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32584157

RESUMO

Serious outbreaks of Alternaria leaf spot and plant decay have recently been recorded on several ornamental plants in the Biella Province (Northern Italy). Twenty-two fungal isolates were obtained from Alternaria infected plant tissues from 13 ornamental hosts. All the isolates were identified morphologically as small-spored Alternaria species. Multilocus sequence typing, carried out by means of ITS, rpb2, tef1, endoPG, Alt a 1, and OPA10-2, assigned 19 isolates as Alternaria alternata, two isolates as belonging to the Alternaria arborescens species complex, and one isolate as an unknown Alternaria sp. Haplotype analyses of ornamental and reference A. alternata isolates from 12 countries identified 14 OPA10-2 and 11 endoPG haplotypes showing a relatively high haplotype diversity. A lack of host specialization or geographic distribution was observed. The host range of the studied A. alternata isolates expanded in cross-pathogenicity assays, and more aggressiveness was frequently observed on the experimental plants than on the host plants from which the fungal isolates were originally isolated. High disease severity, population expansion, intraspecies diversity, and increased range of experimental hosts were seen in the emergence of Alternaria disease on ornamentals. More epidemiological and molecular studies should be performed to better understand these diseases, taking into consideration factors such as seed transmission and ongoing climate changes.


Assuntos
Alternaria , Itália , Virulência
19.
Ecotoxicol Environ Saf ; 201: 110782, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32497817

RESUMO

Klebsiella pneumoniae is one of the most important pathogens related to hospital-acquired infections. The incidence of infections by hypervirulent K. pneumoniae (hvKp), especially community-acquired infections, has been increasing in recent decades. The occurrence of multidrug-resistant (MDR) hvKp has been increasingly reported worldwide decreasing the treatment options, which is a concern. Aquatic environments have been considered a reservoir of MDR pathogens, which contribute to the spread of MDR pathogens. Therefore, this study aimed to characterize MDR-hvKp strains obtained from public aquatic environments using whole genome sequencing in Brazil. Resistome analysis showed ARGs to ß-lactams, quinolones, tetracyclines, sulfonamides, and fosfomycin as well as several metal resistance genes. Virulome analysis showed several virulence genes. Besides, genomic islands, CRISPR and prophage-related sequences were also detected. MLST analysis revealed the presence of two novel sequences types (STs) belonging to different clonal complexes (CCs) [ST4415 (CC515) and ST4416 (CC2654)], and one already described [ST661 (CC661)]. The presence of MDR-hvKp lineages in water sources belonging to STs and CCs associated with humans and animals shows the ability of these pathogens to spread to different aquatic environments. This study reports for the first time two novel STs of MDR-hvKp as well as the presence of a rare ST661 closely related to outbreaks in aquatic environments, and contributes to surveillance studies and MDR-hvKp monitoring worldwide.


Assuntos
Farmacorresistência Bacteriana/genética , Metais , Poluição da Água/análise , Animais , Antibacterianos , Brasil , Genes Bacterianos , Genômica , Humanos , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae/genética , Tipagem de Sequências Multilocus , Virulência/genética , Fatores de Virulência/genética , Sequenciamento Completo do Genoma
20.
Cell ; 182(2): 429-446.e14, 2020 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-32526206

RESUMO

The mode of acquisition and causes for the variable clinical spectrum of coronavirus disease 2019 (COVID-19) remain unknown. We utilized a reverse genetics system to generate a GFP reporter virus to explore severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pathogenesis and a luciferase reporter virus to demonstrate sera collected from SARS and COVID-19 patients exhibited limited cross-CoV neutralization. High-sensitivity RNA in situ mapping revealed the highest angiotensin-converting enzyme 2 (ACE2) expression in the nose with decreasing expression throughout the lower respiratory tract, paralleled by a striking gradient of SARS-CoV-2 infection in proximal (high) versus distal (low) pulmonary epithelial cultures. COVID-19 autopsied lung studies identified focal disease and, congruent with culture data, SARS-CoV-2-infected ciliated and type 2 pneumocyte cells in airway and alveolar regions, respectively. These findings highlight the nasal susceptibility to SARS-CoV-2 with likely subsequent aspiration-mediated virus seeding to the lung in SARS-CoV-2 pathogenesis. These reagents provide a foundation for investigations into virus-host interactions in protective immunity, host susceptibility, and virus pathogenesis.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Pneumonia Viral/patologia , Pneumonia Viral/virologia , Sistema Respiratório/virologia , Genética Reversa/métodos , Idoso , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Betacoronavirus/imunologia , Betacoronavirus/patogenicidade , Linhagem Celular , Células Cultivadas , Chlorocebus aethiops , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/terapia , Fibrose Cística/patologia , DNA Recombinante , Feminino , Furina/metabolismo , Humanos , Imunização Passiva , Pulmão/metabolismo , Pulmão/patologia , Pulmão/virologia , Masculino , Pessoa de Meia-Idade , Mucosa Nasal/metabolismo , Mucosa Nasal/patologia , Mucosa Nasal/virologia , Pandemias , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/imunologia , Sistema Respiratório/patologia , Serina Endopeptidases/metabolismo , Células Vero , Virulência , Replicação Viral
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