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1.
Insect Mol Biol ; 33(3): 228-245, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38348538

RESUMO

Aphid genomic resources enable the study of complex life history traits and provide information on vector biology, host adaption and speciation. The currant-lettuce aphid (Nasonovia ribisnigri (Hemiptera: Aphididae) (Mosley)) is a cosmopolitan pest of outdoor lettuce (Lactuca sativa (Asterales: Asteraceae) (Linnaeus)). Until recently, the use of resistant cultivars was an effective method for managing N. ribisnigri. A resistant cultivar containing a single gene (Nr-locus), introduced in the 1980s, conferred complete resistance to feeding. Overreliance of this Nr-locus in lettuce resulted in N. ribisnigri's ability to break resistance mechanism, with first reports during 2003. Our work attempts to understand which candidate gene(s) are associated with this resistance-breaking mechanism. We present two de novo draft assembles for N. ribisnigri genomes, corresponding to both avirulent (Nr-locus susceptible) and virulent (Nr-locus resistant) biotypes. Changes in gene expression of the two N. ribisnigri biotypes were investigated using transcriptomic analyses of RNA-sequencing (RNA-seq) data to understand the potential mechanisms of resistance to the Nr-locus in lettuce. The draft genome assemblies were 94.2% and 91.4% complete for the avirulent and virulent biotypes, respectively. Out of the 18,872 differentially expressed genes, a single gene/locus was identified in N. ribisnigri that was shared between two resistant-breaking biotypes. This locus was further explored and validated in Real-Time Quantitative Reverse Transcription PCR (qRT-PCR) experiments and has predicted localisations in both the cytoplasm and nucleus. This is the first study to provide evidence that a single gene/locus is likely responsible for the ability of N. ribisnigri to overcome the Nr-locus resistance in the lettuce host.


Assuntos
Afídeos , Lactuca , Lactuca/genética , Lactuca/parasitologia , Afídeos/genética , Animais , Perfilação da Expressão Gênica , Genoma de Inseto , Transcriptoma
2.
Biophys J ; 122(12): 2564-2576, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37177783

RESUMO

Could the phenomenon of catch bonding-force-strengthened cellular adhesion-play a role in sickle cell disease, where abnormal red blood cell (RBC) adhesion obstructs blood flow? Here, we investigate the dynamics of sickle RBCs adhering to a surface functionalized with the protein laminin (a component of the extracellular matrix around blood vessels) under physiologically relevant microscale flow. First, using total internal reflectance microscopy we characterize the spatial fluctuations of the RBC membrane above the laminin surface before detachment. The complex dynamics we observe suggest the possibility of catch bonding, where the mean detachment time of the cell from the surface initially increases to a maximum and then decreases as a function of shear force. We next conduct a series of shear-induced detachment experiments on blood samples from 25 sickle cell disease patients, quantifying the number and duration of adhered cells under both sudden force jumps and linear force ramps. The experiments reveal that a subset of patients does indeed exhibit catch bonding. By fitting the data to a theoretical model of the bond dynamics, we can extract the mean bond lifetime versus force for each patient. The results show a striking heterogeneity among patients, both in terms of the qualitative behavior (whether or not there is catch bonding) and in the magnitudes of the lifetimes. Patients with large bond lifetimes at physiological forces are more likely to have certain adverse clinical features, like a diagnosis of pulmonary arterial hypertension and intracardiac shunts. By introducing an in vitro platform for fully characterizing RBC-laminin adhesion dynamics, our approach could contribute to the development of patient-specific antiadhesive therapies for sickle cell disease. The experimental setup is also easily generalizable to studying adhesion dynamics in other cell types, for example, leukocytes or cancer cells, and can incorporate disease-relevant environmental conditions like oxygen deprivation.


Assuntos
Anemia Falciforme , Laminina , Humanos , Laminina/metabolismo , Eritrócitos , Adesão Celular , Eritrócitos Anormais
3.
Caries Res ; 56(5-6): 503-511, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36318884

RESUMO

The aim of this study was to evaluate the diagnostic reliability of a web-based artificial intelligence program for the detection of interproximal caries in bitewing radiographs. Three hundred bitewing radiographs of patients were subjected to the evaluation of a convolutional neural network. First, the images were visually evaluated by a previously trained and calibrated operator with radiodiagnosis experience. Then, ground truth was established and was clinically validated. For enamel caries, clinical assessment included a combination of clinical-visual and radiography evaluations. For dentin caries, clinical validation was performed by instrumentally accessing the cavity. Second, the images were uploaded and analyzed by the web-based software. Four different models were established to analyze its evaluations according to the confidence threshold (0-100%) offered by the program: model 1 (values >0% were considered positive and values of 0% were considered negative), model 2 (values ≥25% were considered positive and values <25% were considered negative), model 3 (values ≥50% were considered positive and values <50% were considered negative), and model 4 (values ≥75% were considered positive and values <75% were considered negative). The accuracy rate (A), sensitivity (S), specificity (E), positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (PLR), negative likelihood ratio (NLR), and areas under receiver operating characteristic curves (AUC) were calculated for the four models of agreement with the software. Models showed the following results respectively: A = 70.8%, 82%, 85.6%, 86.1%; S = 87%, 69.8%, 57%, 41.6%; E = 66.3%, 85.4%, 93.7%, 98.5%; PPV = 42%, 57.2%, 71.6%, 88.6%; NPV = 94.8%, 91%, 88.6%, 85.8%; PLR = 2.58, 4.78, 9.05, 27.73; NLR = 0.2, 0.35, 0.46, 0.59; AUC = 0.767, 0.777, 0.753, 0.701. Findings in the present study suggest that the artificial intelligence web-based software provides a good diagnostic reliability on the detection of dental caries. Our study highlighted model 2 for showing the best results to differentiate between healthy teeth and decayed teeth.


Assuntos
Cárie Dentária , Humanos , Cárie Dentária/diagnóstico , Inteligência Artificial , Reprodutibilidade dos Testes , Suscetibilidade à Cárie Dentária , Redes Neurais de Computação , Software , Radiografia Interproximal/métodos , Sensibilidade e Especificidade
4.
Polymers (Basel) ; 14(7)2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35406280

RESUMO

The overuse of fossil-based resources to produce thermoplastic materials and rubbers is dramatically affecting the environment, reflected in its clearest way as global warming. As a way of reducing this, multiple efforts are being undertaken including the use of more sustainable alternatives, for instance, those of natural origin as the main feedstock alternative, therefore having a lower carbon footprint. Contributing to this goal, the synthesis of bio-based rubbers based on ß-myrcene and trans-ß-farnesene was addressed in this work. Polymyrcene (PM) and polyfarnesene (PF) were synthesized via coordination polymerization using a neodymium-based catalytic system, and their properties were compared to the conventional polybutadiene (PB) and polyisoprene (PI) also obtained via coordination polymerization. Moreover, different average molecular weights were also tested to elucidate the influence over the materials' properties. The crosslinking of the rubbers was carried out via conventional and efficient vulcanization routes, comparing the final properties of the crosslinking network of bio-based PM and PF with the conventional fossil-based PB and PI. Though the mechanical properties of the crosslinked rubbers improved as a function of molecular weight, the chemical structure of PM and PF (with 2 and 3 unsaturated double bonds, respectively) produced a crosslinking network with lower mechanical properties than those obtained by PB and PI (with 1 unsaturated double bond). The current work contributes to the understanding of improvements (in terms of crosslinking parameters) that are required to produce competitive rubber with good sustainability/performance balance.

6.
Insects ; 12(7)2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34357301

RESUMO

Mitochondrial DNA variations of Peruvian honey bee populations were surveyed by using the tRNAleu-cox2 intergenic region. Only two studies have characterized these populations, indicating the presence of Africanized honey bee colonies in different regions of Peru and varied levels of Africanization, but the current status of its genetic diversity is unknown. A total of 512 honey bee colonies were sampled from three regions to characterize them. Our results revealed the presence of European and African haplotypes: the African haplotypes identified belong to sub-lineage AI (13) and sub-lineage AIII (03), and the European haplotypes to lineages C (06) and M (02). Of 24 haplotypes identified, 15 new sequences are reported here (11 sub-lineage AI, 2 sub-lineage AIII, and 2 lineage M). Peruvian honey bee populations presented a higher proportion from African than European haplotypes. High proportions of African haplotype were reported for Piura and Junín, unlike Lima, which showed more European haplotypes from lineage C. Few colonies belonging to lineage M would represent accidental purchase or traces of the introduction into Peru in the 19th century.

7.
Anal Bioanal Chem ; 413(29): 7147-7156, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34235570

RESUMO

When studying viruses, the most prevalent aspects that come to mind are their structural and functional features, but this leaves in the shadows a quite universal characteristic: their mass. Even if approximations can be derived from size and density measurements, the multi MDa to GDa mass range, featuring a majority of viruses, has so far remained largely unexplored. Recently, nano-electromechanical resonator-based mass spectrometry (NEMS-MS) has demonstrated the ability to measure the mass of intact DNA filled viral capsids in excess of 100 MDa. However, multiple factors have to be taken in consideration when performing NEMS-MS measurements. In this article, phenomena influencing NEMS-MS mass estimates are listed and discussed, including some particle's extraneous physical properties (size, aspect ratio, stiffness), and the influence of frequency noise and device fabrication defects. These factors being accounted for, we could begin to notice subtler effects linked with (e.g.) particle desolvation as a function of operating parameters. Graphical abstract.


Assuntos
Espectrometria de Massas/instrumentação , Espectrometria de Massas/métodos , Nanoestruturas/química , Vírion/química , Calibragem , Capsídeo/química , Desenho de Equipamento , Fagos T/química
9.
JMIR Med Inform ; 9(2): e22976, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33629960

RESUMO

BACKGROUND: Currently, existing biomedical literature repositories do not commonly provide users with specific means to locate and remotely access biomedical databases. OBJECTIVE: To address this issue, we developed the Biomedical Database Inventory (BiDI), a repository linking to biomedical databases automatically extracted from the scientific literature. BiDI provides an index of data resources and a path to access them seamlessly. METHODS: We designed an ensemble of deep learning methods to extract database mentions. To train the system, we annotated a set of 1242 articles that included mentions of database publications. Such a data set was used along with transfer learning techniques to train an ensemble of deep learning natural language processing models targeted at database publication detection. RESULTS: The system obtained an F1 score of 0.929 on database detection, showing high precision and recall values. When applying this model to the PubMed and PubMed Central databases, we identified over 10,000 unique databases. The ensemble model also extracted the weblinks to the reported databases and discarded irrelevant links. For the extraction of weblinks, the model achieved a cross-validated F1 score of 0.908. We show two use cases: one related to "omics" and the other related to the COVID-19 pandemic. CONCLUSIONS: BiDI enables access to biomedical resources over the internet and facilitates data-driven research and other scientific initiatives. The repository is openly available online and will be regularly updated with an automatic text processing pipeline. The approach can be reused to create repositories of different types (ie, biomedical and others).

10.
J Exp Bot ; 72(5): 1634-1648, 2021 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-33249501

RESUMO

The salicinoids are phenolic glycosides that are characteristic secondary metabolites of the Salicaceae, particularly willows and poplars. Despite the well-known pharmacology of salicin, that led to the development of aspirin >100 years ago, the biosynthetic pathways leading to salicinoids have yet to be defined. Here, we describe the identification, cloning, and biochemical characterization of SpUGT71L2 and SpUGT71L3-isozymic glycosyltransferases from Salix purpurea-that function in the glucosylation of ortho-substituted phenols. The best substrate in vitro was salicyl-7-benzoate. Its product, salicyl-7-benzoate glucoside, was shown to be endogenous in poplar and willow. Together they are inferred to be early intermediates in the biosynthesis of salicortin and related metabolites in planta. The role of this UDP-glycosyltransferase was confirmed via the metabolomic analysis of transgenic plants produced by RNAi knockdown of the poplar orthologue (UGT71L1) in the hybrid clone Populus tremula×P. alba, INRA 717-1B4.


Assuntos
Glicosídeos/biossíntese , Glicosiltransferases , Salix , Glicosiltransferases/genética , Plantas Geneticamente Modificadas/enzimologia , Populus/genética , Salix/enzimologia , Salix/genética , Difosfato de Uridina
11.
Langmuir ; 36(43): 13041-13050, 2020 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-33103438

RESUMO

Micrometer scale colloidal particles experiencing ∼kT scale interactions and suspended in a fluid are relevant to a broad spectrum of applications. Often, colloidal particles are anisotropic, either by design or by nature. Yet, there are few techniques by which ∼kT scale interactions of anisotropic particles can be measured. Herein, we present the initial development of scattering morphology resolved total internal reflection microscopy (SMR-TIRM). The hypothesis of this work is that the morphology of light scattered by an anisotropic particle from an evanescent wave is a sensitive function of particle orientation. This hypothesis was tested with experiments and simulations mapping the scattered light from colloidal ellipsoids at systemically varied orientations. Scattering morphologies were first fitted with a two-dimensional (2D) Gaussian surface. The fitted morphology was parameterized by the morphology's orientation angle Mϕ and aspect ratio MAR. Data from both experiments and simulations show Mϕ to be a function of the particle azimuthal angle, while MAR was a sensitive function of the polar angle. This analysis shows that both azimuthal and polar angles of a colloidal ellipsoid could be resolved from scattering morphology as well or better than using bright-field microscopy. The integrated scattering intensity, which will be used for determining the separation distance, was also found to be a sensitive function of particle orientation. A procedure for interpreting these confounding effects was developed that in principle would uniquely determine the separation distance, the azimuthal angle, and the polar angle. Tracking these three quantities is necessary for calculating the potential energy landscape sampled by a colloidal ellipsoid.

12.
Viruses ; 12(9)2020 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-32933109

RESUMO

The Republic of Congo (RoC) declared a chikungunya (CHIK) outbreak on 9 February 2019. We conducted a ONE-Human-Animal HEALTH epidemiological, virological and entomological investigation. Methods: We collected national surveillance and epidemiological data. CHIK diagnosis was based on RT-PCR and CHIKV-specific antibodies. Full CHIKV genome sequences were obtained by Sanger and MinION approaches and Bayesian tree phylogenetic analysis was performed. Mosquito larvae and 215 adult mosquitoes were collected in different villages of Kouilou and Pointe-Noire districts and estimates of Aedes (Ae.) mosquitos' CHIKV-infectious bites obtained. We found two new CHIKV sequences of the East/Central/South African (ECSA) lineage, clustering with the recent enzootic sub-clade 2, showing the A226V mutation. The RoC 2019 CHIKV strain has two novel mutations, E2-T126M and E2-H351N. Phylogenetic suggests a common origin from 2016 Angola strain, from which it diverged around 1989 (95% HPD 1985-1994). The infectious bite pattern was similar for 2017, 2018 and early 2019. One Ae. albopictus pool was RT-PCR positive. The 2019 RoC CHIKV strain seems to be recently introduced or be endemic in sylvatic cycle. Distinct from the contemporary Indian CHIKV isolates and in contrast to the original Central-African strains (transmitted by Ae. aegypti), it carries the A226V mutation, indicating an independent adaptive mutation in response to vector replacement (Ae. albopictus vs Ae. aegypti).


Assuntos
Febre de Chikungunya/epidemiologia , Febre de Chikungunya/virologia , Vírus Chikungunya/classificação , Adolescente , Adulto , Aedes/virologia , Animais , Teorema de Bayes , Vírus Chikungunya/genética , Vírus Chikungunya/fisiologia , Criança , Pré-Escolar , Congo/epidemiologia , Surtos de Doenças , Feminino , Humanos , Larva , Masculino , Pessoa de Meia-Idade , Mosquitos Vetores , Mutação , Filogenia , Adulto Jovem
13.
Viruses ; 12(9)2020 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-32825479

RESUMO

The last seven years have seen the greatest surge of Ebola virus disease (EVD) cases in equatorial Africa, including the 2013-2016 epidemic in West Africa and the recent epidemics in the Democratic Republic of Congo (DRC). The vaccine clinical trials that took place in West Africa and the DRC, as well as follow-up studies in collaboration with EVD survivor communities, have for the first time allowed researchers to compare immune memory induced by natural infection and vaccination. These comparisons may be relevant to evaluate the putative effectiveness of vaccines and candidate medical countermeasures such as convalescent plasma transfer. In this study, we compared the long-term functionality of anti-EBOV glycoprotein (GP) antibodies from EVD survivors with that from volunteers who received the recombinant vesicular stomatitis virus vectored vaccine (rVSV-ZEBOV) during the Phase I clinical trial in Hamburg. Our study highlights important differences between EBOV vaccination and natural infection and provides a framework for comparison with other vaccine candidates.


Assuntos
Anticorpos Antivirais/imunologia , Vacinas contra Ebola/imunologia , Ebolavirus/imunologia , Doença pelo Vírus Ebola/imunologia , Sobreviventes , Adulto , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Vacinas contra Ebola/administração & dosagem , Feminino , Doença pelo Vírus Ebola/prevenção & controle , Doença pelo Vírus Ebola/virologia , Humanos , Imunoglobulinas/sangue , Imunoglobulinas/imunologia , Memória Imunológica , Masculino , Vacinação , Vesiculovirus/imunologia , Proteínas do Envelope Viral/imunologia , Carga Viral
14.
J Virol ; 94(21)2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-32817220

RESUMO

Lassa fever (LF) is a zoonotic viral hemorrhagic fever caused by Lassa virus (LASV), which is endemic to West African countries. Previous studies have suggested an important role for T-cell-mediated immunopathology in LF pathogenesis, but the mechanisms by which T cells influence disease severity and outcome are not well understood. Here, we present a multiparametric analysis of clinical immunology data collected during the 2017-2018 Lassa fever outbreak in Nigeria. During the acute phase of LF, we observed robust activation of the polyclonal T-cell repertoire, which included LASV-specific and antigenically unrelated T cells. However, severe and fatal LF cases were characterized by poor LASV-specific effector T-cell responses. Severe LF was also characterized by the presence of circulating T cells with homing capacity to inflamed tissues, including the gut mucosa. These findings in LF patients were recapitulated in a mouse model of LASV infection, in which mucosal exposure resulted in remarkably high lethality compared to skin exposure. Taken together, our findings indicate that poor LASV-specific T-cell responses and activation of nonspecific T cells with homing capacity to inflamed tissues are associated with severe LF.IMPORTANCE Lassa fever may cause severe disease in humans, in particular in areas of endemicity like Sierra Leone and Nigeria. Despite its public health importance, the pathophysiology of Lassa fever in humans is poorly understood. Here, we present clinical immunology data obtained in the field during the 2018 Lassa fever outbreak in Nigeria indicating that severe Lassa fever is associated with activation of T cells antigenically unrelated to Lassa virus and poor Lassa virus-specific effector T-cell responses. Mechanistically, we show that these bystander T cells express defined tissue homing signatures that suggest their recruitment to inflamed tissues and a putative role of these T cells in immunopathology. These findings open a window of opportunity to consider T-cell targeting as a potential postexposure therapeutic strategy against severe Lassa fever, a hypothesis that could be tested in relevant animal models, such as nonhuman primates.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Surtos de Doenças , Mucosa Intestinal/imunologia , Febre Lassa/imunologia , Vírus Lassa/patogenicidade , Ativação Linfocitária , Adolescente , Adulto , Idoso , Animais , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/patologia , Linfócitos T CD8-Positivos/virologia , Criança , Pré-Escolar , Feminino , Regulação da Expressão Gênica , Antígenos HLA-DR/genética , Antígenos HLA-DR/imunologia , Humanos , Lactente , Recém-Nascido , Integrina beta1/genética , Integrina beta1/imunologia , Interferon gama/genética , Interferon gama/imunologia , Mucosa Intestinal/patologia , Mucosa Intestinal/virologia , Febre Lassa/genética , Febre Lassa/mortalidade , Febre Lassa/virologia , Vírus Lassa/crescimento & desenvolvimento , Vírus Lassa/imunologia , Proteína 1 de Membrana Associada ao Lisossomo/genética , Proteína 1 de Membrana Associada ao Lisossomo/imunologia , Masculino , Camundongos , Pessoa de Meia-Idade , Nigéria/epidemiologia , Estudos Retrospectivos , Índice de Gravidade de Doença , Pele/imunologia , Pele/patologia , Pele/virologia , Análise de Sobrevida , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
15.
J Virol ; 94(1)2019 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-31597768

RESUMO

Some viruses take advantage of conjugation of ubiquitin or ubiquitin-like proteins to enhance their own replication. One example is Ebola virus, which has evolved strategies to utilize these modification pathways to regulate the viral proteins VP40 and VP35 and to counteract the host defenses. Here, we show a novel mechanism by which Ebola virus exploits the ubiquitin and SUMO pathways. Our data reveal that minor matrix protein VP24 of Ebola virus is a bona fide SUMO target. Analysis of a SUMOylation-defective VP24 mutant revealed a reduced ability to block the type I interferon (IFN) pathway and to inhibit IFN-mediated STAT1 nuclear translocation, exhibiting a weaker interaction with karyopherin 5 and significantly diminished stability. Using glutathione S-transferase (GST) pulldown assay, we found that VP24 also interacts with SUMO in a noncovalent manner through a SIM domain. Mutation of the SIM domain in VP24 resulted in a complete inability of the protein to downmodulate the IFN pathway and in the monoubiquitination of the protein. We identified SUMO deubiquitinating enzyme ubiquitin-specific-processing protease 7 (USP7) as an interactor and a negative modulator of VP24 ubiquitination. Finally, we show that mutation of one ubiquitination site in VP24 potentiates the IFN modulatory activity of the viral protein and its ability to block IFN-mediated STAT1 nuclear translocation, pointing to the ubiquitination of VP24 as a negative modulator of the VP24 activity. Altogether, these results indicate that SUMO interacts with VP24 and promotes its USP7-mediated deubiquitination, playing a key role in the interference with the innate immune response mediated by the viral protein.IMPORTANCE The Ebola virus VP24 protein plays a critical role in escape of the virus from the host innate immune response. Therefore, deciphering the molecular mechanisms modulating VP24 activity may be useful to identify potential targets amenable to therapeutics. Here, we identify the cellular proteins USP7, SUMO, and ubiquitin as novel interactors and regulators of VP24. These interactions may represent novel potential targets to design new antivirals with the ability to modulate Ebola virus replication.


Assuntos
Ebolavirus/genética , Regulação da Expressão Gênica , Interações Hospedeiro-Patógeno/genética , Proteína SUMO-1/química , Peptidase 7 Específica de Ubiquitina/genética , Proteínas Virais/química , Animais , Sítios de Ligação , Chlorocebus aethiops , Ebolavirus/imunologia , Ebolavirus/patogenicidade , Células HEK293 , Células HeLa , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunidade Inata , Interferon Tipo I/genética , Interferon Tipo I/imunologia , Modelos Moleculares , Mutação , Ligação Proteica , Conformação Proteica , Domínios Proteicos , Transporte Proteico , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/imunologia , Proteína SUMO-1/genética , Proteína SUMO-1/imunologia , Transdução de Sinais , Sumoilação , Peptidase 7 Específica de Ubiquitina/imunologia , Células Vero , Proteínas Virais/genética , Proteínas Virais/imunologia , alfa Carioferinas/genética , alfa Carioferinas/imunologia
16.
JCI Insight ; 4(21)2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31550241

RESUMO

Filoviruses of the genus Ebolavirus include 6 species with marked differences in their ability to cause disease in humans. From the highly virulent Ebola virus to the seemingly nonpathogenic Reston virus, case fatality rates can range between 0% and 90%. In order to understand the molecular basis of these differences, it is imperative to establish disease models that recapitulate human disease as faithfully as possible. Nonhuman primates (NHPs) are the gold-standard models for filovirus pathogenesis, but comparative studies are skewed by the fact that Reston virus infection can be lethal for NHPs. Here we used HLA-A2-transgenic, NOD-scid-IL-2γ receptor-knockout (NSG-A2) mice reconstituted with human hematopoiesis to compare Ebola virus and Reston virus pathogenesis in a human-like environment. While markedly less pathogenic than Ebola virus, Reston virus killed 20% of infected mice, a finding that was linked to exacerbated inflammation and viral replication in the liver. In addition, the case fatality ratios of different Ebolavirus species in humans were recapitulated in the humanized mice. Our findings point to humanized mice as a putative model to test the pathogenicity of newly discovered filoviruses, and suggest that further investigations on Reston virus pathogenesis in humans are warranted.


Assuntos
Doença pelo Vírus Ebola/patologia , Animais , Modelos Animais de Doenças , Ebolavirus/patogenicidade , Ebolavirus/fisiologia , Doença pelo Vírus Ebola/virologia , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Mucosa/virologia , Carga Viral , Replicação Viral
17.
AMIA Annu Symp Proc ; 2019: 457-466, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32308839

RESUMO

The integration of genetic information in current clinical routine has raised a need for tools to exploit family genetic knowledge. On the clinical side, an application for managing and visualizing pedigree diagrams could provide genetics specialists with an integrated environment with potential positive impact on their current practice. This article presents a web tool (genoDraw) that provides clinical practitioners with the ability to create, maintain and visualize patients' and their families' information in the form of pedigree diagrams. genoDraw implements a graph-based three-step process for generating diagrams according to a de facto standard in the area and clinical terminologies. It also complies with five characteristics identified as indispensable for the next-generation of pedigree drawing software: comprehensiveness, data-drivenness, automation, interactivity and compatibility with biomedical vocabularies. The platform was implemented and tested, confirming its potential interest to clinical routine.


Assuntos
Ontologias Biológicas , Gráficos por Computador , Linhagem , Terminologia como Assunto , Humanos , Internet , Software , Vocabulário Controlado
18.
Science ; 362(6417): 918-922, 2018 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-30467165

RESUMO

Measurement of the mass of particles in the mega- to gigadalton range is challenging with conventional mass spectrometry. Although this mass range appears optimal for nanomechanical resonators, nanomechanical mass spectrometers often suffer from prohibitive sample loss, extended analysis time, or inadequate resolution. We report on a system architecture combining nebulization of the analytes from solution, their efficient transfer and focusing without relying on electromagnetic fields, and the mass measurements of individual particles using nanomechanical resonator arrays. This system determined the mass distribution of ~30-megadalton polystyrene nanoparticles with high detection efficiency and effectively performed molecular mass measurements of empty or DNA-filled bacteriophage T5 capsids with masses up to 105 megadaltons using less than 1 picomole of sample and with an instrument resolution above 100.


Assuntos
Capsídeo/química , Capsídeo/ultraestrutura , Espectrometria de Massas/métodos , Nanotecnologia/métodos , DNA Viral/química , Campos Eletromagnéticos , Nanopartículas/química , Poliestirenos/química , Fagos T/química , Fagos T/ultraestrutura
19.
J Virol ; 92(11)2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29514907

RESUMO

Zaire and Sudan ebolavirus species cause a severe disease in humans and nonhuman primates (NHPs) characterized by a high mortality rate. There are no licensed therapies or vaccines against Ebola virus disease (EVD), and the recent 2013 to 2016 outbreak in West Africa highlighted the need for EVD-specific medical countermeasures. Here, we generated and characterized head-to-head the immunogenicity and efficacy of five vaccine candidates against Zaire ebolavirus (EBOV) and Sudan ebolavirus (SUDV) based on the highly attenuated poxvirus vector modified vaccinia virus Ankara (MVA) expressing either the virus glycoprotein (GP) or GP together with the virus protein 40 (VP40) forming virus-like particles (VLPs). In a human monocytic cell line, the different MVA vectors (termed MVA-EBOVs and MVA-SUDVs) triggered robust innate immune responses, with production of beta interferon (IFN-ß), proinflammatory cytokines, and chemokines. Additionally, several innate immune cells, such as dendritic cells, neutrophils, and natural killer cells, were differentially recruited in the peritoneal cavity of mice inoculated with MVA-EBOVs. After immunization of mice with a homologous prime/boost protocol (MVA/MVA), total IgG antibodies against GP or VP40 from Zaire and Sudan ebolavirus were differentially induced by these vectors, which were mainly of the IgG1 and IgG3 isotypes. Remarkably, an MVA-EBOV construct coexpressing GP and VP40 protected chimeric mice challenged with EBOV to a greater extent than a vector expressing GP alone. These results support the consideration of MVA-EBOVs and MVA-SUDVs expressing GP and VP40 and producing VLPs as best-in-class potential vaccine candidates against EBOV and SUDV.IMPORTANCE EBOV and SUDV cause a severe hemorrhagic fever affecting humans and NHPs. Since their discovery in 1976, they have caused several sporadic epidemics, with the recent outbreak in West Africa from 2013 to 2016 being the largest and most severe, with more than 11,000 deaths being reported. Although some vaccines are in advanced clinical phases, less expensive, safer, and more effective licensed vaccines are desirable. We generated and characterized head-to-head the immunogenicity and efficacy of five novel vaccines against EBOV and SUDV based on the poxvirus MVA expressing GP or GP and VP40. The expression of GP and VP40 leads to the formation of VLPs. These MVA-EBOV and MVA-SUDV recombinants triggered robust innate and humoral immune responses in mice. Furthermore, MVA-EBOV recombinants expressing GP and VP40 induced high protection against EBOV in a mouse challenge model. Thus, MVA expressing GP and VP40 and producing VLPs is a promising vaccine candidate against EBOV and SUDV.


Assuntos
Vacinas contra Ebola/imunologia , Ebolavirus/imunologia , Glicoproteínas/imunologia , Doença pelo Vírus Ebola/prevenção & controle , Proteínas da Matriz Viral/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Linhagem Celular Tumoral , Quimiocinas/imunologia , Embrião de Galinha , República Democrática do Congo , Células Dendríticas/imunologia , Ebolavirus/genética , Glicoproteínas/biossíntese , Glicoproteínas/genética , Células HEK293 , Células HeLa , Doença pelo Vírus Ebola/imunologia , Doença pelo Vírus Ebola/virologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Interferon beta/imunologia , Células Matadoras Naturais/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Neutrófilos/imunologia , Sudão , Vacinação , Vacinas de DNA , Proteínas da Matriz Viral/biossíntese , Proteínas da Matriz Viral/genética , Vacinas Virais/genética
20.
Nanomaterials (Basel) ; 7(11)2017 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-29137126

RESUMO

This study presents the impact of carbon nanotubes (CNTs) on mitochondrial oxygen mass flux (Jm) under three experimental conditions. New experimental results and a new methodology are reported for the first time and they are based on CNT Raman spectra star graph transform (spectral moments) and perturbation theory. The experimental measures of Jm showed that no tested CNT family can inhibit the oxygen consumption profiles of mitochondria. The best model for the prediction of Jm for other CNTs was provided by random forest using eight features, obtaining test R-squared (R²) of 0.863 and test root-mean-square error (RMSE) of 0.0461. The results demonstrate the capability of encoding CNT information into spectral moments of the Raman star graphs (SG) transform with a potential applicability as predictive tools in nanotechnology and material risk assessments.

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