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1.
Environ Res ; 252(Pt 2): 118918, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38614198

RESUMO

In this study, the removal of two emerging pollutants (EPs), antipyrine and acetanilide, through adsorption on activated carbons (ACs) prepared by chemical activation of Organosolv lignin with H3PO4 were evaluated. ACs with different pore size distribution were obtained at different impregnation ratios (H3PO4/lignin, 0.5-3.0 w/w) and activating temperatures (500-900 °C). The porosity and surface chemistry of the ACs were determined, and a bimodal size distribution of micropores and narrow mesopores was observed for the different ACs. These ACs were tested for antipyrine and acetanilide adsorption in aqueous solutions in a batch system at 20 °C and low concentration levels (0.5-10 ppm). In general, the ACs exhibited higher adsorption affinity to acetanilide than to antipyrine due to its smaller molecular size. Langmuir adsorption isotherm was able to describe the adsorption equilibrium data. A new Linear Driving Force (2-LDF) kinetic model, based on the bimodal size distribution of micropores and narrow mesopores observed for the ACs has been developed. The new model provided a more accurate description of the batch adsorption rates than that obtained from conventional kinetic models, and also enabled to relate the pore size distribution of the adsorbent with the adsorption kinetics. The validity of this model was checked in small-scale column fixed bed adsorption for the AC showing the highest affinity for both EP. The kinetic model and equilibrium adsorption isotherm obtained from the batch experiments were successfully used to provide an accurate description of the bed service time and the full breakthrough profile of acetanilide and antipyrine.


Assuntos
Acetanilidas , Antipirina , Lignina , Adsorção , Lignina/química , Antipirina/química , Acetanilidas/química , Carvão Vegetal/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise
2.
Orphanet J Rare Dis ; 18(1): 390, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38102667

RESUMO

BACKGROUND: The availability of multiple treatments for type 1 Gaucher disease increases the need for real-life studies to evaluate treatment efficacy and safety and provide clinicians with more information to choose the best personalized therapy for their patients. AIMS: To determine whether treatment with eliglustat produces, in adult GD1 patients, ans optimal response in daily clinical practice. METHODS: We designed a real-life study with 2 years of follow-up (TRAZELGA [GEE-ELI-2017-01]) to uniformly evaluate the response and adverse events to eliglustat treatment. This study, conducted in 30 patients across Spain and previously treated with other therapies, included the evaluation of safety and efficacy by assessing visceral enlargement, bone disease (DEXA and T and Z scores), concomitant treatments and adverse events, as well as a quality of life evaluation (SF-36). In addition, the quantification of classical biomarkers (chitotriosidase activity, CCL18/PARC and glucosylsphingosine (GluSph)) and new candidates for GD biomarkers (YKL-40, cathepsin S, hepcidin and lipocalin-2 determined by immunoassay) were also assessed. Non-parametric statistical analysis was performed and p < 0.05 was considered statistically significant. MAIN RESULTS: Thirty patients were enrolled in the study. The median age was 41.5 years and the male-female ratio was 1.1:1. 84% of the patients had received ERT and 16% SRT as previous treatment. The most common symptoms at baseline were fatigue (42%) and bone pain (38%), no patient had a bone crisis during the study, and two years after switching, 37% had reduced their use of analgesics. Patient-reported outcomes showed a significant increase in physical function scores (p = 0.027) and physical pain scores (p = 0.010). None of the enrolled patients discontinued treatment due to adverse events, which were mild and transient in nature, mainly gastrointestinal and skin dryness. None of the biomarkers show a significant increase or decompensation after switching. CCL18/PARC (p = 0.0012), YKL-40 (p = 0.00004) and lipocalin-2 (p = 0.0155) improved after two years and GluSph after one year (p = 0.0008) and two years (p = 0.0245) of oral therapy. CONCLUSION: In summary, this real-life study, showed that eliglustat maintains stability and can improve quality of life with few side effects. Significant reductions in classic and other novel biomarkers were observed after two years of therapy.


Assuntos
Doenças Ósseas , Doença de Gaucher , Adulto , Humanos , Masculino , Feminino , Doença de Gaucher/tratamento farmacológico , Doença de Gaucher/diagnóstico , Proteína 1 Semelhante à Quitinase-3 , Lipocalina-2 , Seguimentos , Qualidade de Vida , Biomarcadores , Dor
3.
Nanomaterials (Basel) ; 13(22)2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-37999275

RESUMO

The aim of this work is to establish the Oxygen Reduction Reaction (ORR) activity of self-standing electrospun carbon fiber catalysts obtained from different metallic salt/lignin solutions. Through a single-step electrospinning technique, freestanding carbon fiber (CF) electrodes embedded with various metal nanoparticles (Co, Fe, Pt, and Pd), with 8-16 wt% loadings, were prepared using organosolv lignin as the initial material. These fibers were formed from a solution of lignin and ethanol, into which the metallic salt precursors were introduced, without additives or the use of toxic reagents. The resulting non-woven cloths were thermostabilized in air and then carbonized at 900 °C. The presence of metals led to varying degrees of porosity development during carbonization, improving the accessibility of the electrolyte to active sites. The obtained Pt and Pd metal-loaded carbon fibers showed high nanoparticle dispersion. The performance of the electrocatalyst for the oxygen reduction reaction was assessed in alkaline and acidic electrolytes and compared to establish which metals were the most suitable for producing carbon fibers with the highest electrocatalytic activity. In accordance with their superior dispersion and balanced pore size distribution, the carbon fibers loaded with 8 wt% palladium showed the best ORR activity, with onset potentials of 0.97 and 0.95 V in alkaline and acid media, respectively. In addition, this electrocatalyst exhibits good stability and selectivity for the four-electron energy pathway while using lower metal loadings compared to commercial catalysts.

4.
Polymers (Basel) ; 15(20)2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37896307

RESUMO

In this study, electrospun carbon fiber electrodes were prepared by the carbonization of PAN-Fe3O4 electrospun fibers at 800 °C for their use as catalysts in the oxygen reduction reaction in an alkaline electrolyte. Magnetic nanofiber mats were fabricated using a needle-free electrospinning method by incorporating magnetic nanoparticles into a polymer solution. Electrochemical tests revealed that the oxygen reduction reaction (ORR) activity is optimized at an intermediate magnetite loading of 30% wt. These catalysts not only show better performance compared to their counterparts but also achieve high selectivity to water at low potentials. The onset and half-wave potentials of 0.92 and 0.76 V shown by these samples are only slightly behind those of the commercial Pt 20%-carbon black ORR catalyst. The obtained results point out that the electrospinning of PAN-Fe3O4 solutions allows the preparation of advanced N-Fe ORR catalysts in fibrillar morphology.

5.
Ind Eng Chem Res ; 60(51): 18791-18805, 2021 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-34992332

RESUMO

Porous SiO2 nanospheres were modified with different loadings of ZrO2 to obtain catalysts with a Si/Zr molar ratio from 2.5 to 30. These materials were characterized by X-ray diffraction, transmission and scanning electron microscopies, N2 adsorption-desorption at -196 °C, X-ray photoelectron spectroscopy and pyridine and 2-6-dimethylpyridine thermoprogrammed desorption. The characterization of these catalysts has revealed that a high proportion of Zr favors the formation of Lewis acid sites, which are implied in catalytic transfer hydrogenation processes, whereas the low Brönsted acidity promotes a dehydration reaction, being possible to give rise to a large variety of products from furfural through consecutive reactions, such as furfuryl alcohol, i-propyl furfuryl ether, i-propyl levulinate, and γ-valerolactone, in a range of temperature of 110-170 °C and 1-6 h of reaction.

6.
Materials (Basel) ; 12(15)2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31357532

RESUMO

Activated carbon monoliths (ACMs), with 25 cells/cm2, were prepared from the direct extrusion of Alcell, Kraft lignin and olives stones particles that were impregnated with phosphoric acid, followed by activation at 700 °C. These ACMs were used as catalysts for methanol dehydration reaction under air atmosphere. ACM that was prepared from olive stone and at impregnation ratio of 2, OS2, showed the highest catalytic activity, with a methanol conversion of 75%, a selectivity to dimethyl ether (DME) higher than 90%, and a great stability under the operating conditions studied. The results suggest that the monolithic conformation, with a density channel of 25 cells/cm2 avoid the blockage of active sites by coke deposition to a large extent. Methanol conversion for OS2 was reduced to 29% in the presence of 8%v water, at 350 °C, although the selectivity to DME remained higher than 86%. A kinetic model of methanol dehydration in the presence of air was developed, while taking into account the competitive adsorption of water. A Langmuir-Hinshelwood mechanism, whose rate-limiting step was the surface reaction between two adsorbed methanol molecules, represented the experimental data under the conditions studied very well. An activation energy value of 92 kJ/mol for methanol dehydration reaction and adsorption enthalpies for methanol and water of -12 and -35 kJ/mol, respectively, were obtained.

7.
mBio ; 10(1)2019 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-30670614

RESUMO

Homologous recombination (HR) enables the exchange of genetic material between and within species. Recent studies suggest that this process plays a major role in the microevolution of microbial genomes, contributing to core genome homogenization and to the maintenance of cohesive population structures. However, we still have a very poor understanding of the possible adaptive roles of intraspecific HR and of the factors that determine its differential impact across clades and lifestyles. Here we used a unified methodological framework to assess HR in 338 complete genomes from 54 phylogenetically diverse and representative prokaryotic species, encompassing different lifestyles and a broad phylogenetic distribution. Our results indicate that lifestyle and presence of restriction-modification (RM) machineries are among the main factors shaping HR patterns, with symbionts and intracellular pathogens having the lowest HR levels. Similarly, the size of exchanged genomic fragments correlated with the presence of RM and competence machineries. Finally, genes exchanged by HR showed functional enrichments which could be related to adaptations to different environments and ecological strategies. Taken together, our results clarify the factors underlying HR impact and suggest important adaptive roles of genes exchanged through this mechanism. Our results also revealed that the extent of genetic exchange correlated with lifestyle and some genomic features. Moreover, the genes in exchanged regions were enriched for functions that reflected specific adaptations, supporting identification of HR as one of the main evolutionary mechanisms shaping prokaryotic core genomes.IMPORTANCE Microbial populations exchange genetic material through a process called homologous recombination. Although this process has been studied in particular organisms, we lack an understanding of its differential impact over the genome and across microbes with different life-styles. We used a common analytical framework to assess this process in a representative set of microorganisms. Our results uncovered important trends. First, microbes with different lifestyles are differentially impacted, with endosymbionts and obligate pathogens being those less prone to undergo this process. Second, certain genetic elements such as restriction-modification systems seem to be associated with higher rates of recombination. Most importantly, recombined genomes show the footprints of natural selection in which recombined regions preferentially contain genes that can be related to specific ecological adaptations. Taken together, our results clarify the relative contributions of factors modulating homologous recombination and show evidence for a clear a role of this process in shaping microbial genomes and driving ecological adaptations.


Assuntos
Adaptação Biológica , Archaea/genética , Bactérias/genética , Evolução Molecular , Genoma Arqueal , Genoma Bacteriano , Recombinação Homóloga , Biologia Computacional
8.
Polymers (Basel) ; 10(7)2018 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-30960660

RESUMO

Polyacrylonitrile (PAN) is one of the materials most often used for carbonization. PAN nanofiber mats, created by electrospinning, are an especially interesting source to gain carbon nanofibers. A well-known problem in this process is fixing the PAN nanofiber mats during the stabilization process which is necessary to avoid contraction of the fibers, correlated with an undesired increase in the diameter and undesired bending. Fixing this issue typically results in breaks in the nanofiber mats if the tension is too high, or it is not strong enough to keep the fibers as straight as in the original state. This article suggests a novel method to overcome this problem by electrospinning on an aluminum substrate on which the nanofiber mat adheres rigidly, stabilizing the composite and carbonizing afterwards either with or without the aluminum substrate to gain either a pure carbon nanofiber mat or a metal/carbon composite.

9.
Diagn Cytopathol ; 45(12): 1065-1072, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28949442

RESUMO

BACKGROUND: European guidelines recommend primary HPV testing for cervical cancer screening. However, the starting age remains to be defined, with an undecided window between 30 and 35 years. This pilot study compares the effectiveness of primary HPV testing to that of cytology for the detection of high-grade (CIN2+) lesions stratified by age. METHODS: Cotesting with LBC cytology and APTIMA® HPV (AHPV) was performed in 5053 women aged 25-65 in an opportunistic screening program in Madrid. AHPV-positive cases were referred to colposcopy and genotyped for HPV16 and 18/45 (AHPV-GT). Results were analyzed stratified in four age groups. RESULTS: 454 cases (9.0%) were AHPV-positive. Women under 35 had a 30.2% CIN2+ rate, compared to 21.9% and 20.4% for women aged 35-44 or 45-54. There was a significant increase (P < .05) in the rate of CIN2+ in AHPV-GT-positive women when compared to that for other HPV types (AHPV-other), being 43.3% versus 15.7%. AHPV-GT-positive women under 35 had significantly higher rates of CIN2+ lesions than any other age-group. The sensitivity of cytology for cervical CIN2+ in APHV-positive women was 60.6%. All 4 carcinomas, including one AHPV-negative endometrial adenocarcinoma, had abnormal cytology. All cervical CIN2+ lesions biopsied were AHPV-positive. CONCLUSIONS: Aptima HPV shows a significantly higher sensitivity for cervical CIN2+ lesions than cytology alone. Unexpectedly, AHPV-positive women under 35 had the highest incidence of CIN2+ lesions, particularly when they are HPV16/18/45-positive. Reconsidering HPV primary screening before the recommended age of 35 is warranted.


Assuntos
Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/patologia , Adulto , Idoso , Biópsia , Colposcopia/métodos , Citodiagnóstico/métodos , Detecção Precoce de Câncer/métodos , Feminino , Genótipo , Humanos , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Proteínas Oncogênicas Virais/genética , Papillomaviridae/genética , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia , Projetos Piloto , Neoplasias do Colo do Útero/virologia
10.
Antiviral Res ; 142: 30-36, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28315707

RESUMO

Foot-and-mouth disease virus (FMDV) is the causative agent of a highly contagious disease and a major concern in animal health worldwide. We have previously reported the use of RNA transcripts mimicking structural domains in the non-coding regions of the FMDV RNA as potent type-I interferon (IFN) inducers showing antiviral effect in vivo, as well as their immunomodulatory properties in combination with an FMD vaccine in mice. Here, we describe the enhancing effect of RNA delivery on the immunogenicity and protection induced by a suboptimal dose of a conventional FMD vaccine in pigs. Animals receiving the RNA developed earlier and higher levels of neutralizing antibodies against homologous and heterologous isolates, compared to those immunized with the vaccine alone, and had higher anti-FMDV titers at late times post-vaccination. RNA delivery also induced higher specific T-cell response and protection levels against FMDV challenge. Peripheral blood mononuclear cells from pigs inoculated with RNA and the vaccine had a higher IFN-γ specific response than those from pigs receiving the vaccine alone. When challenged with FMDV, all three animals immunized with the conventional vaccine developed antibodies to the non-structural viral proteins 3ABC and two of them developed severe signs of disease. In the group receiving the vaccine together with the RNA, two pigs were fully protected while one showed delayed and mild signs of disease. Our results support the immunomodulatory effect of these RNA molecules in natural hosts and suggest their potential use for improvement of FMD vaccines strategies.


Assuntos
Vírus da Febre Aftosa/imunologia , Febre Aftosa/imunologia , Febre Aftosa/prevenção & controle , RNA/administração & dosagem , RNA/imunologia , Vacinas Virais/imunologia , Adjuvantes Imunológicos/administração & dosagem , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Feminino , Vírus da Febre Aftosa/genética , Imunoglobulina G/sangue , Interferon Tipo I/imunologia , Interferon gama/imunologia , Cinética , Leucócitos Mononucleares/imunologia , RNA/síntese química , Pequeno RNA não Traduzido , Suínos , Doenças dos Suínos/prevenção & controle , Linfócitos T/imunologia , Vacinação , Proteínas não Estruturais Virais/imunologia
11.
Nanomedicine ; 12(5): 1185-92, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26970026

RESUMO

In this work we have tested the potential antiviral activity of silver nanoparticles formulated as Argovit™ against Rift Valley fever virus (RVFV). The antiviral activity of Argovit was tested on Vero cell cultures and in type-I interferon receptor deficient mice (IFNAR (-/-) mice) by two different approaches: (i) different dilutions of Argovit were added to previously infected cells or administrated to animals infected with a lethal dose of virus; (ii) virus was pre-incubated with different dilutions of Argovit before inoculation in mice or cells. Though the ability of silver nanoparticles to control an ongoing RVFV infection in the conditions tested was limited, the incubation of virus with Argovit before the infection led to a reduction of the infectivity titers both in vitro and in vivo. These results reveal the potential application of silver nanoparticles to control the infectivity of RVFV, which is an important zoonotic pathogen.


Assuntos
Antivirais/farmacologia , Nanopartículas/uso terapêutico , Vírus da Febre do Vale do Rift/efeitos dos fármacos , Prata/uso terapêutico , Animais , Camundongos , Febre do Vale de Rift/prevenção & controle , Vírus da Febre do Vale do Rift/patogenicidade
12.
Proc Natl Acad Sci U S A ; 111(23): E2423-30, 2014 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-24912181

RESUMO

To modulate the expression of genes involved in nitrogen assimilation, the cyanobacterial PII-interacting protein X (PipX) interacts with the global transcriptional regulator NtcA and the signal transduction protein PII, a protein found in all three domains of life as an integrator of signals of the nitrogen and carbon balance. PipX can form alternate complexes with NtcA and PII, and these interactions are stimulated and inhibited, respectively, by 2-oxoglutarate, providing a mechanistic link between PII signaling and NtcA-regulated gene expression. Here, we demonstrate that PipX is involved in a much wider interaction network. The effect of pipX alleles on transcript levels was studied by RNA sequencing of S. elongatus strains grown in the presence of either nitrate or ammonium, followed by multivariate analyses of relevant mutant/control comparisons. As a result of this process, 222 genes were classified into six coherent groups of differentially regulated genes, two of which, containing either NtcA-activated or NtcA-repressed genes, provided further insights into the function of NtcA-PipX complexes. The remaining four groups suggest the involvement of PipX in at least three NtcA-independent regulatory pathways. Our results pave the way to uncover new regulatory interactions and mechanisms in the control of gene expression in cyanobacteria.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Ligação a DNA/genética , Regulação Bacteriana da Expressão Gênica , Synechococcus/genética , Fatores de Transcrição/genética , Compostos de Amônio/metabolismo , Compostos de Amônio/farmacologia , Proteínas de Bactérias/metabolismo , Sequência de Bases , Proteínas de Ligação a DNA/metabolismo , Perfilação da Expressão Gênica/classificação , Ácidos Cetoglutáricos/farmacologia , Modelos Genéticos , Dados de Sequência Molecular , Análise Multivariada , Mutação , Nitratos/metabolismo , Nitratos/farmacologia , Nitrogênio/metabolismo , Nitrogênio/farmacologia , Motivos de Nucleotídeos/genética , Proteínas PII Reguladoras de Nitrogênio/genética , Proteínas PII Reguladoras de Nitrogênio/metabolismo , Regiões Promotoras Genéticas/genética , Ligação Proteica/efeitos dos fármacos , Homologia de Sequência do Ácido Nucleico , Synechococcus/metabolismo , Fatores de Transcrição/metabolismo , Sítio de Iniciação de Transcrição
13.
Vaccine ; 31(40): 4375-81, 2013 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-23859841

RESUMO

We have recently described the antiviral effect in mice of in vitro-transcribed RNAs mimicking structural domains in the non-coding regions of the foot-and-mouth disease virus (FMDV) genome RNA. These small, synthetic and non-infectious RNA molecules (ncRNAs) are potent type-I interferon (IFN) inducers in vivo. In this work, the immunomodulatory effect of the ncRNA corresponding to the internal ribosome entry site (IRES) on immunization with two different FMD vaccine formulations, both based on inactivated virus, including or not a commercial adjuvant, was analyzed in the mice model. The effect of the time interval between RNA inoculation and immunization was also studied. RNA delivery consistently increased the titers of specific anti-FMDV antibodies, including neutralizing antibodies, elicited after vaccination. Moreover, at day 2 after immunization, significant differences in mean antibody titers could be detected between the groups of mice receiving either vaccine co-administered with the RNA and the control group, unlike those immunized with the vaccine alone. When vaccinated mice were challenged with FMDV, the mean values of viral load were lower in the groups receiving the RNA together with the vaccine. Our results show the enhancing effect of the IRES RNA on the immune response elicited after vaccination and suggest the potential of this molecule as an adjuvant for new FMD vaccine design.


Assuntos
Vírus da Febre Aftosa/imunologia , Febre Aftosa/imunologia , RNA/administração & dosagem , Vacinas Virais/imunologia , Adjuvantes Imunológicos/administração & dosagem , Animais , Animais Domésticos/imunologia , Anticorpos Neutralizantes , Anticorpos Antivirais/sangue , Febre Aftosa/prevenção & controle , Interferon Tipo I/biossíntese , Interferon Tipo I/imunologia , Camundongos , Camundongos Endogâmicos ICR , RNA/imunologia , Vacinação , Carga Viral/imunologia
14.
PLoS One ; 8(7): e70197, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23894615

RESUMO

African horse sickness virus (AHSV) belongs to the genus Orbivirus. We have now engineered naked DNAs and recombinant modified vaccinia virus Ankara (rMVA) expressing VP2 and NS1 proteins from AHSV-4. IFNAR((-/-)) mice inoculated with DNA/rMVA-VP2,-NS1 from AHSV-4 in an heterologous prime-boost vaccination strategy generated significant levels of neutralizing antibodies specific of AHSV-4. In addition, vaccination stimulated specific T cell responses against the virus. The vaccine elicited partial protection against an homologous AHSV-4 infection and induced cross-protection against the heterologous AHSV-9. Similarly, IFNAR((-/-)) mice vaccinated with an homologous prime-boost strategy with rMVA-VP2-NS1 from AHSV-4 developed neutralizing antibodies and protective immunity against AHSV-4. Furthermore, the levels of immunity were very high since none of vaccinated animals presented viraemia when they were challenged against the homologous AHSV-4 and very low levels when they were challenged against the heterologous virus AHSV-9. These data suggest that the immunization with rMVA/rMVA was more efficient in protection against a virulent challenge with AHSV-4 and both strategies, DNA/rMVA and rMVA/rMVA, protected against the infection with AHSV-9. The inclusion of the protein NS1 in the vaccine formulations targeting AHSV generates promising multiserotype vaccines.


Assuntos
Vírus da Doença Equina Africana/imunologia , Doença Equina Africana/imunologia , Modelos Animais de Doenças , Proteínas não Estruturais Virais/imunologia , Vacinas Virais/imunologia , Doença Equina Africana/prevenção & controle , Vírus da Doença Equina Africana/classificação , Animais , Linhagem Celular , Chlorocebus aethiops , Cavalos , Masculino , Camundongos , Camundongos da Linhagem 129 , Receptor de Interferon alfa e beta/genética , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Células Vero , Proteínas não Estruturais Virais/genética
15.
PLoS One ; 8(4): e60574, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23593251

RESUMO

The protective efficacy of recombinant vaccines expressing serotype 8 bluetongue virus (BTV-8) capsid proteins was tested in a mouse model. The recombinant vaccines comprised plasmid DNA or Modified Vaccinia Ankara viruses encoding BTV VP2, VP5 or VP7 proteins. These constructs were administered alone or in combination using either a homologous prime boost vaccination regime (rMVA/rMVA) or a heterologous vaccination regime (DNA/rMVA). The DNA/rMVA or rMVA/rMVA prime-boost were administered at a three week interval and all of the animals that received VP2 generated neutralising antibodies. The vaccinated and non-vaccinated-control mice were subsequently challenged with a lethal dose of BTV-8. Mice vaccinated with VP7 alone were not protected. However, mice vaccinated with DNA/rMVA or rMVA/rMVA expressing VP2, VP5 and VP7 or VP2 alone were all protected.


Assuntos
Vírus Bluetongue/imunologia , Bluetongue/imunologia , Bluetongue/prevenção & controle , Proteínas do Capsídeo/imunologia , Receptor de Interferon alfa e beta/deficiência , Vacinas de DNA/imunologia , Vacinas Sintéticas/imunologia , Animais , Anticorpos Neutralizantes/sangue , Bluetongue/sangue , Bluetongue/virologia , Galinhas , Chlorocebus aethiops , Camundongos , Plasmídeos/imunologia , RNA Viral/sangue , Receptor de Interferon alfa e beta/metabolismo , Vacinação , Células Vero , Viremia/imunologia , Viremia/prevenção & controle , Viremia/virologia
16.
MAbs ; 2(3): 275-84, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20400862

RESUMO

This paper describes the generation of monoclonal antibodies directed to immunogenic nucleoprotein N epitopes of Rift Valley fever virus (RVFV), and their application in diagnostics, both for antibody detection in competitive ELISA and for antigen capture in a sandwich ELISA. Monoclonal antibodies (mAbs) were generated after DNA immunization of Balb/c mice and characterized by western blot, ELISA and cell immunostaining assays. At least three different immunorelevant epitopes were defined by mAb competition assays. Interestingly, two of the mAbs generated were able to distinguish between RVFV strains from Egyptian or South African lineages. These monoclonal antibodies constitute useful tools for diagnosis, especially for the detection of serum anti-RVFV antibodies from a broad range of species by means of competitive ELISA.


Assuntos
Anticorpos Monoclonais/imunologia , Imunização , Proteínas do Nucleocapsídeo/imunologia , Febre do Vale de Rift/diagnóstico , Vírus da Febre do Vale do Rift/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/biossíntese , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Antígenos Virais/análise , Western Blotting , Ensaio de Imunoadsorção Enzimática , Epitopos/imunologia , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Proteínas do Nucleocapsídeo/biossíntese , Plasmídeos/genética , Plasmídeos/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/imunologia , Febre do Vale de Rift/sangue , Alinhamento de Sequência
17.
J Clin Microbiol ; 46(12): 3971-9, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18842943

RESUMO

Noroviruses (NoVs) are responsible for the majority of gastroenteritis outbreaks in humans. Recently, NoV strains which are genetically closely related to human genogroup II (GII) NoVs have been detected in fecal specimens from swine. These findings have raised concern about the possible role of pigs as reservoirs for NoVs that could infect humans. To better understand the epidemiology of swine NoVs in both the swine and the human populations, rapid immunoassays are needed. In this study, baculovirus recombinants were generated to express the capsid gene of a swine NoV GII genotype 11 (GII.11) strain which self-assembled into virus-like particles (VLPs). Subsequently, the purified VLPs were used to evoke monoclonal antibodies (MAbs) in mice. A panel of eight promising MAbs was obtained and evaluated for their ability to bind to heterologous VLPs, denaturated antigens, and truncated capsid proteins. The MAbs could be classified into two groups: two MAbs that recognized linear epitopes located at the amino-terminal half (shell domain) of the swine NoV GII.11 VLPs and that cross-reacted with human GII.4 NoV VLPs. The other six MAbs bound to conformational epitopes and did not cross-react with the human GII.4 VLPs. To our knowledge, this is the first report on the characterization of MAbs against swine NoVs. The swine NoV VLPs and the MAbs described here may be further used for the design of diagnostic reagents that could help increase our knowledge of the prevalence of NoV infections in pigs and the possible role of pigs as reservoirs for NoVs.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Infecções por Caliciviridae/veterinária , Proteínas do Capsídeo/imunologia , Proteínas do Capsídeo/metabolismo , Norovirus/imunologia , Virossomos/imunologia , Virossomos/metabolismo , Animais , Anticorpos Monoclonais/isolamento & purificação , Baculoviridae/genética , Infecções por Caliciviridae/virologia , Linhagem Celular , Reações Cruzadas , Epitopos/imunologia , Feminino , Humanos , Lepidópteros , Camundongos , Camundongos Endogâmicos BALB C , Suínos
18.
J Comp Neurol ; 496(6): 802-18, 2006 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-16628617

RESUMO

We investigated in the mouse and chick the neuroepithelial origin and development of the locus coeruleus (LoC), the most important noradrenergic neuronal population in the brain. We first studied the topography of the developing LoC in the hindbrain, using as markers the key noradrenergic marker gene Dbh and the transcription factors Phox2a and Phox2b (upstream of Dbh). In both mouse and chicken, LoC neurons first appear arranged linearly along the middle one-third of the alar plate of rhombomere 1 (r1), collinear to a reference ventricular longitudinal band that early on expresses Phox2a and Phox2b in the alar plate of r2 and later expands to r1. Double-labeling experiments with LoC markers (Dbh or Phox2a) and either alar (Pax7 and Rnx3) or basal (Otp) genetic markers suggested that LoC cells migrate from their origin in the alar plate to a final position in the lateral basal plate. To corroborate these suggestions experimentally and determine the precise origin of the LoC, we fate mapped the LoC in the chick at stage HH11 by using quail-chick homotopic grafts. The experimental results confirmed that the LoC originates in the alar plate throughout the rostrocaudal extent of r1 and ruled out a rostrocaudal translocation. They also corroborated a ventralward tangential migration of LoC cells into the lateral basal plate, where the postmigratory LoC primordium is located. Comparisons with neighboring alar r1-derived cell populations established that LoC neurons originate outside the cerebellum, in a matrix area intercalated dorsoventrally between the sources of the prospective vestibular and trigeminal columns.


Assuntos
Locus Cerúleo/citologia , Neurônios/fisiologia , Animais , Biomarcadores/metabolismo , Movimento Celular , Embrião de Galinha , Dopamina beta-Hidroxilase/metabolismo , Desenvolvimento Embrionário , Proteínas de Homeodomínio/metabolismo , Imuno-Histoquímica , Locus Cerúleo/embriologia , Camundongos , Proteínas do Tecido Nervoso/metabolismo , Células Neuroepiteliais/fisiologia , Fator de Transcrição PAX7/metabolismo , Codorniz , Rombencéfalo/embriologia , Rombencéfalo/metabolismo , Rombencéfalo/transplante , Especificidade da Espécie , Fatores de Transcrição/metabolismo
19.
FEMS Microbiol Lett ; 254(1): 41-7, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16451177

RESUMO

Cyanobacteria respond to nutrient stress conditions by degrading their light-harvesting complexes for photosynthesis, a process regulated in Synechococcus sp. PCC 7942 by the sensor histidine kinase non-bleaching sensor (NblS). In yeast two-hybrid screenings for proteins interacting with NblS we have identified a novel type of protein, named SipA for NblS interacting protein A. Specific binding between NblS and SipA is observed with both yeast and bacterial two-hybrid systems. Additional yeast two-hybrid screenings with SipA as bait further confirmed the specificity of the interaction and allowed us to map their determinants to the ATP-binding domain of NblS. Strong conservation and coevolution of both NblS and SipA in cyanobacteria further suggests the importance of SipA in the context of the NblS signal transduction network.


Assuntos
Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Resposta ao Choque Térmico , Proteínas Quinases/metabolismo , Transdução de Sinais , Synechococcus/fisiologia , Trifosfato de Adenosina/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Sítios de Ligação , Histidina Quinase , Dados de Sequência Molecular , Proteínas Quinases/química , Synechococcus/genética , Synechococcus/metabolismo , Técnicas do Sistema de Duplo-Híbrido
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