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1.
Cell Microbiol ; 23(4): e13302, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33432690

RESUMO

With no available therapies, infections with Zika virus (ZIKV) constitute a major public health concern as they can lead to congenital microcephaly. In order to generate an intracellular environment favourable to viral replication, ZIKV induces endomembrane remodelling and the morphogenesis of replication factories via enigmatic mechanisms. In this study, we identified the AAA+ type ATPase valosin-containing protein (VCP) as a cellular interaction partner of ZIKV non-structural protein 4B (NS4B). Importantly, its pharmacological inhibition as well as the expression of a VCP dominant-negative mutant impaired ZIKV replication. In infected cells, VCP is relocalised to large ultrastructures containing both NS4B and NS3, which are reminiscent of dengue virus convoluted membranes. Moreover, short treatment with the VCP inhibitors NMS-873 or CB-5083 drastically decreased the abundance and size of ZIKV-induced convoluted membranes. Furthermore, NMS-873 treatment inhibited ZIKV-induced mitochondria elongation previously reported to be physically and functionally linked to convoluted membranes in case of the closely related dengue virus. Finally, VCP inhibition resulted in enhanced apoptosis of ZIKV-infected cells strongly suggesting that convoluted membranes limit virus-induced cytopathic effects. Altogether, this study identifies VCP as a host factor required for ZIKV life cycle and more precisely, for the maintenance of viral replication factories. Our data further support a model in which convoluted membranes regulate ZIKV life cycle by impacting on mitochondrial functions and ZIKV-induced death signals in order to create a cytoplasmic environment favourable to viral replication.


Assuntos
Adenosina Trifosfatases/metabolismo , Apoptose , Regulação da Expressão Gênica , Proteína com Valosina/genética , Proteína com Valosina/metabolismo , Zika virus/genética , Zika virus/fisiologia , Acetanilidas/farmacologia , Adenosina Trifosfatases/genética , Animais , Benzotiazóis/farmacologia , Linhagem Celular Tumoral , Chlorocebus aethiops , Células HEK293 , Interações entre Hospedeiro e Microrganismos/efeitos dos fármacos , Interações entre Hospedeiro e Microrganismos/genética , Humanos , Indóis/farmacologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/virologia , Pirimidinas/farmacologia , Proteína com Valosina/antagonistas & inibidores , Células Vero
2.
J Appl Clin Med Phys ; 21(8): 173-182, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32506590

RESUMO

PURPOSE: To present an open-source software (https://github.com/CHUSRadOncPhys/FluoMV) for monitoring intrafraction motion that is based on the visualization of superimposed contours of projected region-of-interests from DICOM RTSTRUCT files on cine-MV images acquired and displayed in real-time during radiation therapy delivery. Clinical use with prostate gold fiducial markers is presented. METHODS: Projections of regions of interest (ROI) in the reference frame of the electronic portal imaging device are computed offline for different gantry angles before the first treatment fraction. During treatment delivery, the contrast of portal images is automatically adjusted using a histogram equalization algorithm. The projections associated with the current gantry angle are then superimposed on the images in real time. This allows the therapist to evaluate if the imaged structures of interest remain within their respective contours during treatment delivery and to potentially interrupt the treatment if deemed necessary. The spatial accuracy of the method was evaluated by imaging a ball bearing phantom in a set-up where the position of the projected ROI is highly sensitive to gantry angle errors. The visibility of fiducial markers during one fraction of seven different volumetric modulated arc therapy (VMAT) prostate treatments is characterized. RESULTS: The geometric validation showed a negligible systematic error µ < 0.1 mm for the position of the projections. The random errors associated with the time accuracy of the gantry angle readout were characterized by standard deviations σ ≤ 0.6 mm. The VMAT clinical treatments showed that the fiducial markers were frequently visible, allowing for a meaningful clinical use. CONCLUSIONS: The results demonstrate that the method presented is sufficiently accurate to be used for intrafraction monitoring of patients. The fact that this method could be implemented on many modern linacs at little to no cost and with no additional dose delivered to the patients makes this solution very attractive for improving patient care and safety in radiation therapy.


Assuntos
Radioterapia de Intensidade Modulada , Marcadores Fiduciais , Humanos , Masculino , Imagens de Fantasmas , Planejamento da Radioterapia Assistida por Computador , Software
3.
Traffic ; 18(6): 362-377, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28295920

RESUMO

In this study, newly identified host interactors of hepatitis C virus (HCV) proteins were assessed for a role in modulating the innate immune response. The analysis revealed enrichment for components of the nuclear transport machinery and the crucial interaction with NS3/4A protein in suppression of interferon-ß (IFNB1) induction. Using a comprehensive microscopy-based high-content screening approach combined to the gene silencing of nuclear transport factors, we showed that NS3/4A-interacting proteins control the nucleocytoplasmic trafficking of IFN regulatory factor 3 (IRF3) and NF-κB p65 upon Sendai virus (SeV) infection. Notably, importin ß1 (IMPß1) knockdown-a hub protein highly targeted by several viruses-decreases the nuclear translocation of both transcription factors and prevents IFNB1 and IFIT1 induction, correlating with a rapid increased of viral proteins and virus-mediated apoptosis. Here we show that NS3/4A triggers the cleavage of IMPß1 and inhibits nuclear transport to disrupt IFNB1 production. Importantly, mutated IMPß1 resistant to cleavage completely restores signaling, similar to the treatment with BILN 2061 protease inhibitor, correlating with the disappearance of cleavage products. Overall, the data indicate that HCV NS3/4A targeting of IMPß1 and related modulators of IRF3 and NF-κB nuclear transport constitute an important innate immune subversion strategy and inspire new avenues for broad-spectrum antiviral therapies.


Assuntos
Proteínas de Transporte/metabolismo , Fator Regulador 3 de Interferon/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Proteínas não Estruturais Virais/metabolismo , beta Carioferinas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/imunologia , Antivirais/farmacologia , Hepacivirus , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Carioferinas/metabolismo , Inibidores de Proteases/farmacologia
4.
PLoS Pathog ; 13(1): e1006174, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28118396

RESUMO

[This corrects the article DOI: 10.1371/journal.ppat.1005772.].

5.
PLoS Pathog ; 12(7): e1005772, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27454487

RESUMO

Spliceosomal SNRNP200 is a Ski2-like RNA helicase that is associated with retinitis pigmentosa 33 (RP33). Here we found that SNRNP200 promotes viral RNA sensing and IRF3 activation through the ability of its amino-terminal Sec63 domain (Sec63-1) to bind RNA and to interact with TBK1. We show that SNRNP200 relocalizes into TBK1-containing cytoplasmic structures upon infection, in contrast to the RP33-associated S1087L mutant, which is also unable to rescue antiviral response of SNRNP200 knockdown cells. This functional rescue correlates with the Sec63-1-mediated binding of viral RNA. The hindered IFN-ß production of knockdown cells was further confirmed in peripheral blood cells of RP33 patients bearing missense mutation in SNRNP200 upon infection with Sendai virus (SeV). This work identifies a novel immunoregulatory role of the spliceosomal SNRNP200 helicase as an RNA sensor and TBK1 adaptor for the activation of IRF3-mediated antiviral innate response.


Assuntos
Imunidade Inata/imunologia , Fator Regulador 3 de Interferon/imunologia , RNA Viral/imunologia , Ribonucleoproteínas Nucleares Pequenas/imunologia , Viroses/imunologia , Western Blotting , Ensaio de Imunoadsorção Enzimática , Imunofluorescência , Técnicas de Silenciamento de Genes , Humanos , Imunoprecipitação , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase , Proteínas Serina-Treonina Quinases/imunologia , Transdução de Sinais/imunologia , Spliceossomos/imunologia
6.
BMC Bioinformatics ; 18(1): 209, 2017 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-28399820

RESUMO

BACKGROUND: Structural interaction frequency matrices between all genome loci are now experimentally achievable thanks to high-throughput chromosome conformation capture technologies. This ensues a new methodological challenge for computational biology which consists in objectively extracting from these data the structural motifs characteristic of genome organisation. RESULTS: We deployed the fast multi-scale community mining algorithm based on spectral graph wavelets to characterise the networks of intra-chromosomal interactions in human cell lines. We observed that there exist structural domains of all sizes up to chromosome length and demonstrated that the set of structural communities forms a hierarchy of chromosome segments. Hence, at all scales, chromosome folding predominantly involves interactions between neighbouring sites rather than the formation of links between distant loci. CONCLUSIONS: Multi-scale structural decomposition of human chromosomes provides an original framework to question structural organisation and its relationship to functional regulation across the scales. By construction the proposed methodology is independent of the precise assembly of the reference genome and is thus directly applicable to genomes whose assembly is not fully determined.


Assuntos
Algoritmos , Cromatina/ultraestrutura , Cromossomos Humanos/ultraestrutura , Biologia Computacional/métodos , Genoma Humano , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Análise de Sequência de DNA
7.
J Clin Microbiol ; 53(12): 3738-49, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26354816

RESUMO

Respiratory syncytial virus (RSV) rapid antigen detection tests (RADT) are extensively used in clinical laboratories. We performed a systematic review and meta-analysis to evaluate the accuracy of RADTs for diagnosis of RSV infection and to determine factors associated with accuracy estimates. We searched EMBASE and PubMed for diagnostic-accuracy studies of commercialized RSV RADTs. Studies reporting sensitivity and specificity data compared to a reference standard (reverse transcriptase PCR [RT-PCR], immunofluorescence, or viral culture) were considered. Two reviewers independently extracted data on study characteristics, diagnostic-accuracy estimates, and study quality. Accuracy estimates were pooled using bivariate random-effects regression models. Heterogeneity was investigated with prespecified subgroup analyses. Seventy-one articles met inclusion criteria. Overall, RSV RADT pooled sensitivity and specificity were 80% (95% confidence interval [CI], 76% to 83%) and 97% (95% CI, 96% to 98%), respectively. Positive- and negative-likelihood ratios were 25.5 (95% CI, 18.3 to 35.5) and 0.21 (95% CI, 0.18 to 0.24), respectively. Sensitivity was higher in children (81% [95% CI, 78%, 84%]) than in adults (29% [95% CI, 11% to 48%]). Because of this disparity, further subgroup analyses were restricted to pediatric data (63 studies). Test sensitivity was poorest using RT-PCR as a reference standard and highest using immunofluorescence (74% versus 88%; P < 0.001). Industry-sponsored studies reported significantly higher sensitivity (87% versus 78%; P = 0.01). Our results suggest that the poor sensitivity of RSV RADTs in adults may preclude their use in this population. Furthermore, industry-sponsored studies and those that did not use RT-PCR as a reference standard likely overestimated test sensitivity.


Assuntos
Antígenos Virais/análise , Imunoensaio/métodos , Infecções por Vírus Respiratório Sincicial/diagnóstico , Vírus Sinciciais Respiratórios/isolamento & purificação , Adulto , Criança , Pré-Escolar , Humanos , Sensibilidade e Especificidade , Fatores de Tempo
8.
J Am Mosq Control Assoc ; 39(1): 12-17, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-37043605

RESUMO

Mosquito suppression strategies based on "rear and release" of male mosquitoes are attracting renewed interest from governments, municipalities, and private businesses. These include irradiation-based sterile insect technique, Wolbachia-based technologies, and genetic modification. Each of these approaches requires the mass rearing and release of adult male mosquitoes, which typically is accomplished via a rearing facility near the release site. Although some release programs have relied on centralized rearing and shipment of adult males, adult male mosquitoes are relatively fragile, and their fitness can be diminished by temperature fluctuations, humidity, nutritional deficiencies, and other stresses that occur during shipment. Furthermore, expensive, expedited shipment is typically used to maximize the amount of adult lifetime in the field following the release. In contrast, Aedes aegypti and Ae. albopictus eggs can be desiccated and stored for long periods. They are small, and many millions of eggs can be shipped without specialized environmental conditions and using less expensive means. Here we examine a model in which mosquito eggs are centrally produced and then mailed to satellite rearing facilities. As a control, a replicate set of eggs was reared at the factory of origin. At each of the rearing sites, cloud-based software was used to track and compare rearing at the different locations. The results demonstrate similar rearing outcomes (i.e., egg hatch, immature development, and number of adult males) at each of the different sites for both species. We discuss the outcome in relation to downstream applications and potential future studies.


Assuntos
Aedes , Animais , Masculino , Umidade , Controle de Mosquitos/métodos
9.
J Biol Chem ; 286(23): 20901-12, 2011 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-21502316

RESUMO

A novel double deletion in cardiac troponin T (cTnT) of two highly conserved amino acids (Asn-100 and Glu-101) was found in a restrictive cardiomyopathic (RCM) pediatric patient. Clinical evaluation revealed the presence of left atrial enlargement and marked left ventricle diastolic dysfunction. The explanted heart examined by electron microscopy revealed myofibrillar disarray and mild fibrosis. Pedigree analysis established that this mutation arose de novo. The patient tested negative for six other sarcomeric genes. The single and double recombinant cTnT mutants were generated, and their functional consequences were analyzed in porcine skinned cardiac muscle. In the adult Tn environment (cTnT3 + cardiac troponin I), the single cTnT3-ΔN100 and cTnT3-ΔE101 mutations had opposing effects on the Ca(2+) sensitivity of force development compared with WT, whereas the double deletion cTnT3-ΔN100/ΔE101 increased the Ca(2+) sensitivity + 0.19 pCa units. In addition, cTnT3-ΔN100/ΔE101 decreased the cooperativity of force development, suggesting alterations in intrafilament protein-protein interactions. In the fetal Tn environment, (cTnT1 + slow skeletal troponin I), the single (cTnT1-ΔN110) and double (cTnT1-ΔN110/ΔE111) deletions did not change the Ca(2+) sensitivity compared with control. To recreate the patient's heterozygous genotype, we performed a reconstituted ATPase activity assay. Thin filaments containing 50:50 cTnT3-ΔN100/ΔE101:cTnT3-WT also increased the myofilament Ca(2+) sensitivity compared with WT. Co-sedimentation of thin filament proteins indicated that no significant changes occurred in the binding of Tn containing the RCM cTnT mutation to actin-Tm. This report reveals the protective role of Tn fetal isoforms as they rescue the increased Ca(2+) sensitivity produced by a cTnT-RCM mutation and may account for the lack of lethality during gestation.


Assuntos
Cardiomiopatia Restritiva , Mutação INDEL , Contração Miocárdica , Miocárdio , Troponina T , Citoesqueleto de Actina/genética , Citoesqueleto de Actina/metabolismo , Citoesqueleto de Actina/patologia , Adulto , Animais , Cálcio/metabolismo , Cardiomiopatia Restritiva/genética , Cardiomiopatia Restritiva/metabolismo , Cardiomiopatia Restritiva/patologia , Criança , Pré-Escolar , Feminino , Genótipo , Humanos , Masculino , Miocárdio/metabolismo , Miocárdio/patologia , Linhagem , Proteínas Recombinantes , Suínos , Troponina T/genética , Troponina T/metabolismo
10.
Eur Heart J ; 32(5): 568-73, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21169613

RESUMO

AIMS: Although ventricular septal defects (VSD) are the most common congenital heart lesion, familial clustering has been described only in rare instances. The aim of this study was to identify genetic factors and chromosomal regions contributing to VSD. METHODS AND RESULTS: A unique, large kindred segregating various forms of septal pathologies-including VSD, ventricular septal aneurysms, and atrial septal defects (ASD)-was ascertained and characterized clinically and genetically. Eighteen family members in three generations could be studied, out of whom 10 are affected (2 ASD, 3 septal aneurysm, 4 VSD, and 1 tetralogy of Fallot). Parametric multipoint LOD scores reach significance on chromosome 10p15.3-10p15.2 (max. 3.29). The LOD score support interval is in a gene-poor region where deletions have been reported to associate with septal defects, but that is distinct from the DiGeorge syndrome 2 region on 10p. Multiple linkage analysis scenarios suggest that tetralogy of Fallot is a phenocopy and genetically distinct from the autosomal dominant form of septal pathologies observed in this family. CONCLUSION: This study maps a rare familial form of VSD/septal aneurysms to chromosome 10p15 and extends the spectrum of the genetic heterogeneity of septal pathologies. Fine mapping, haplotype construction, and resequencing will provide a unique opportunity to study the pathogenesis of septal defects and shed light on molecular mechanisms of septal development.


Assuntos
Cromossomos Humanos Par 10/genética , Ligação Genética/genética , Aneurisma Cardíaco/genética , Comunicação Interventricular/genética , Feminino , Humanos , Masculino , Linhagem , Fenótipo , Tetralogia de Fallot/genética
11.
Cell Rep ; 39(1): 110623, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-35385722

RESUMO

Motor skill learning requires the activity of the dorsal striatum, with a differential global implication of the dorsomedial and dorsolateral territories. We investigate here whether and how specific striatal neurons encode the acquisition and consolidation of a motor skill. Using ex vivo two-photon calcium imaging after rotarod training, we report that highly active (HA) striatal populations arise from distinct spatiotemporal reorganization in the dorsomedial (DMS) and dorsolateral (DLS) striatum networks and are correlated with learning performance. The DMS overall activity decreases in early training, with few and sparsely distributed HA cells, while the DLS shows a progressive and long-lasting formation of HA cell clusters. These reorganizations result from reinforcement of synaptic connections to the DMS and anatomical rearrangements to the DLS. Targeted silencing of DMS or DLS HA cells with the cFos-TRAP strategy strongly impairs individual performance. Our data reveal that discrete domains of striatal populations encode acquisition and long-lasting retention of a motor skill.


Assuntos
Aprendizagem , Destreza Motora , Corpo Estriado/fisiologia , Aprendizagem/fisiologia , Destreza Motora/fisiologia , Neostriado , Neurônios/fisiologia
12.
Nat Food ; 3(1): 11-18, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-37118482

RESUMO

Restructuring farmer-researcher relationships and addressing complexity and uncertainty through joint exploration are at the heart of On-Farm Experimentation (OFE). OFE describes new approaches to agricultural research and innovation that are embedded in real-world farm management, and reflects new demands for decentralized and inclusive research that bridges sources of knowledge and fosters open innovation. Here we propose that OFE research could help to transform agriculture globally. We highlight the role of digitalization, which motivates and enables OFE by dramatically increasing scales and complexity when investigating agricultural challenges.

13.
Med Phys ; 38(5): 2754-61, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21776812

RESUMO

PURPOSE: Three dimensional dose polymer gel dosimetry measurements provide unique information on sophisticated dose distributions. In this study, the authors propose a novel method to improve the accuracy of polymer gel dosimeters by inserting a plastic scintillation detector (PSD) to provide a dose reference. METHODS: PSD dosimeters were calibrated using chromatic deconvolution and then inserted into polyacrylanide gel (PAG) dosimeters. The gel and the PSDs were immersed into water and irradiated with 6 MV wedge filtered beams to obtain a wide range of dose variation. Calibration vials containing the same gel were also irradiated to generate a standard calibration curve. The distribution of magnetic nuclear transverse relaxation rate (R2) values of the gel was determined with a multislice multiecho MRI sequence at 1.5 T. Another calibration curve was obtained by assigning the R2 values in the gel surrounding the scintillators to the dose determined by the PSDs. A reference calibration point from a PSD located in a low dose gradient area served to correct the standard calibration method yielding three novel calibration methods. The results were compared with EBT2 GAFCHROMIC film measurements acquired in the same condition and with the Pinnacle3 treatment planning dose calculations, RESULTS: The mean absolute error of the standard calibration method ranged from 6.1 to 12.4%. The corresponding gamma index (3%/3 mm distance to agreement) criterion was satisfied for only 56% of the pixels in the middle slice of the gel compared to Pinnacle3 dose calculations and to EBT2 film measurements in the center part of the field. Calibration methods using a PSD reduced the mean absolute error to less than 4%; this value was under 2.6% for one of the three methods. In that case, 98% of the pixels satisfied the gamma index criterion. CONCLUSIONS: The accuracy of PAG dosimeters may be highly improved using one reference dose point measurement using a plastic scintillation detector. The best calibration procedure corrected the slope of the calibration curve derived from the calibration vials to match the R2 value around a PSD calibration, while keeping the R2 value at 0 Gy constant.


Assuntos
Algoritmos , Géis/efeitos da radiação , Plásticos/efeitos da radiação , Contagem de Cintilação/instrumentação , Dosimetria Termoluminescente/instrumentação , Calibragem , Canadá , Desenho de Equipamento , Análise de Falha de Equipamento , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
J Acoust Soc Am ; 127(3): 1239-43, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20329822

RESUMO

The stiffness of a consolidated granular medium experiences a drop immediately after a moderate mechanical solicitation. Then the stiffness rises back toward its initial value, following a logarithmic time evolution called slow dynamics. In the literature, slow dynamics has been probed by macroscopic quantities averaged over the sample volume, for instance, by the resonant frequency of vibrational eigenmodes. This article presents a different approach based on diffuse acoustic wave spectroscopy, a technique that is directly sensitive to the details of the sample structure. The parameters of the dynamics are found to depend on the damage of the medium. Results confirm that slow dynamics is, at least in part, due to tiny structural rearrangements at the microscopic scale, such as inter-grain contacts.


Assuntos
Modelos Teóricos , Espectrografia do Som , Ultrassom , Elasticidade , Transdutores , Vibração
15.
PLoS One ; 14(2): e0211511, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30730911

RESUMO

A two year long experimental dataset in which authors of Radin, et al., 2016 claim to find evidence of mind-matter interaction is independently re-analyzed. In this experiment, participants are asked to periodically shift their attention towards or away from a double-slit optical apparatus. Shifts in fringe visibility of the interference pattern are monitored and tested against the common sense null hypothesis that such shifts should not correlate with the participant's attention state. We propose a deeper analysis of the dataset, identifying all the necessary arbitrary pre-analysis choices one needs to make, and carefully assessing the results' robustness regarding these choices. Results are twofold. Firstly, even with a conservative correction for the multiple statistical tests the analysis calls for, we confirm the existence of significant although small anomalies in the direction predicted by the mind-matter interaction hypothesis. On the other hand, and unlike Radin, et al., 2016, we also report significant although even smaller anomalies in the control dataset. This leads us to conclude that this particular dataset does not provide strong evidence of mind-matter interaction, yet certainly contains inexplicable anomalies that should motivate replication attempts in highly controlled environments.


Assuntos
Atenção/fisiologia , Comportamento de Escolha , Humanos
16.
Vaccines (Basel) ; 7(4)2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31658677

RESUMO

With 40% of the world population at risk, infections with dengue virus (DENV) constitute a serious threat to public health. While there is no antiviral therapy available against this potentially lethal disease, the efficacy of the only approved vaccine is not optimal and its safety has been recently questioned. In order to develop better vaccines based on attenuated and/or chimeric viruses, one must consider how the human immune system is engaged during DENV infection. The activation of the innate immunity through the detection of viruses by cellular sensors is the first line of defence against those pathogens. This triggers a cascade of events which establishes an antiviral state at the cell level and leads to a global immunological response. However, DENV has evolved to interfere with the innate immune signalling at multiple levels, hence dampening antiviral responses and favouring viral replication and dissemination. This review elaborates on the interplay between DENV and the innate immune system. A special focus is given on the viral countermeasure mechanisms reported over the last decade which should be taken into consideration during vaccine development.

17.
J Immunol Res ; 2018: 9480497, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29854853

RESUMO

The role of the innate immune response in detecting RNA viruses is crucial for the establishment of proper inflammatory and antiviral responses. Different receptors, known as pattern recognition receptors (PRRs), are present in the cytoplasm, endosomes, and on the cellular surface. These receptors have the capacity to sense the presence of viral nucleic acids as pathogen-associated molecular patterns (PAMPs). This recognition leads to the induction of type 1 interferons (IFNs) as well as inflammatory cytokines and chemokines. In this review, we provide an overview of the significant involvement of cellular RNA helicases and Toll-like receptors (TLRs) 3, 7, and 8 in antiviral immune defenses.


Assuntos
Moléculas com Motivos Associados a Patógenos/imunologia , RNA Viral/imunologia , Receptores Toll-Like/metabolismo , Viroses/imunologia , Vírus/imunologia , Animais , Citocinas/metabolismo , Humanos , Imunidade Inata , Mediadores da Inflamação/metabolismo , Interferon Tipo I/metabolismo , RNA Helicases/metabolismo , Vírus/genética
18.
Am J Trop Med Hyg ; 98(2): 524-533, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29260654

RESUMO

Seasonal malaria chemoprevention (SMC) for children < 5 is a strategy that is gaining popularity in West African countries. Although its efficacy to reduce malaria incidence has been demonstrated in trials, the effects of SMC implemented in routine program conditions, outside of experimental contexts, are unknown. In 2014 and 2015, a survey was conducted in 1,311 households located in Kaya District (Burkina Faso) where SMC had been recently introduced. All children < 72 months were tested for malaria and anemia. A pre-post study with control group was designed to measure SMC impact during high transmission season. A difference-in-differences approach was coupled in the analysis with propensity score weighting to control for observable and time-invariant nonobservable confounding factors. SMC reduced the parasitemia point and period prevalence by 3.3 and 24% points, respectively; this translated into protective effects of 51% and 62%. SMC also reduced the likelihood of having moderate to severe anemia by 32%, and history of recent fever by 46%. Self-reported coverage for children at the first cycle was 83%. The SMC program was successfully added to a package of interventions already in place. To our knowledge, with prevalence < 10% during the peak of the transmission season, this is the first time that malaria can be reported as hypo-endemic in a sub-Sahelian setting in Burkina Faso. SMC has great potential, and along with other interventions, it could contribute to approaching the threshold where elimination strategies will be envisioned in Burkina Faso.


Assuntos
Antimaláricos/administração & dosagem , Quimioprevenção/normas , Malária/prevenção & controle , Estações do Ano , Adolescente , Adulto , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Burkina Faso/epidemiologia , Quimioprevenção/métodos , Quimioprevenção/estatística & dados numéricos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Malária/tratamento farmacológico , Malária/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Desenvolvimento de Programas/métodos
19.
Materials (Basel) ; 10(5)2017 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-28772912

RESUMO

Structural health monitoring (SHM) is emerging as an essential tool for constant monitoring of safety-critical engineering components. Ultrasonic guided waves stand out because of their ability to propagate over long distances and because they can offer good estimates of location, severity, and type of damage. The unique properties of the fundamental shear horizontal guided wave (SH0) mode have recently generated great interest among the SHM community. The aim of this paper is to demonstrate the feasibility of omnidirectional SH0 SHM in a thin aluminum plate using a three-transducer sparse array. Descriptions of the transducer, the finite element model, and the imaging algorithm are presented. The image localization maps show a good agreement between the simulations and experimental results. The SH0 SHM method proposed in this paper is shown to have a high resolution and to be able to locate defects within 5% of the true location. The short input signal as well the non-dispersive nature of SH0 leads to high resolution in the reconstructed images. The defect diameter estimated using the full width at half maximum was 10 mm or twice the size of the true diameter.

20.
Methods Mol Biol ; 1401: 233-52, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26831712

RESUMO

Polyketides and nonribosomal peptides constitute two large families of microbial natural products. Over the past 20 years a broad range of microbial polyketide and nonribosomal peptide biosynthetic pathways have been characterized leading to a surfeit of genetic data on polyketide and nonribosomal peptide biosynthesis. We developed the ClusterMine360 database, which stores the antiSMASH-based annotation of gene clusters in the NCBI database, linking the structure of the natural product to the biosynthetic gene cluster. This database is searchable and enables the user to access multiple sequence files for phylogenetic analysis of polyketide and nonribosomal peptide biosynthetic genes. Herein we describe how to add compound families and gene clusters to the database and search it using key words or structures to identify specific gene clusters. We also describe how to download multiple sequence files for specific catalytic domains from polyketide and nonribosomal peptide biosynthesis.


Assuntos
Bactérias/genética , Vias Biossintéticas , Genômica/métodos , Família Multigênica , Biossíntese de Peptídeos Independentes de Ácido Nucleico , Policetídeos/metabolismo , Bactérias/metabolismo , Produtos Biológicos/química , Produtos Biológicos/metabolismo , Bases de Dados Genéticas , Peptídeos/química , Peptídeos/metabolismo , Policetídeos/química
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