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1.
N Engl J Med ; 387(26): 2411-2424, 2022 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-36516078

RESUMO

BACKGROUND: Questions remain concerning the rapidity of immune responses and the durability and safety of vaccines used to prevent Zaire Ebola virus disease. METHODS: We conducted two randomized, placebo-controlled trials - one involving adults and one involving children - to evaluate the safety and immune responses of three vaccine regimens against Zaire Ebola virus disease: Ad26.ZEBOV followed by MVA-BN-Filo 56 days later (the Ad26-MVA group), rVSVΔG-ZEBOV-GP followed by placebo 56 days later (the rVSV group), and rVSVΔG-ZEBOV-GP followed by rVSVΔG-ZEBOV-GP 56 days later (the rVSV-booster group). The primary end point was antibody response at 12 months, defined as having both a 12-month antibody concentration of at least 200 enzyme-linked immunosorbent assay units (EU) per milliliter and an increase from baseline in the antibody concentration by at least a factor of 4. RESULTS: A total of 1400 adults and 1401 children underwent randomization. Among both adults and children, the incidence of injection-site reactions and symptoms (e.g., feverishness and headache) was higher in the week after receipt of the primary and second or booster vaccinations than after receipt of placebo but not at later time points. These events were largely low-grade. At month 12, a total of 41% of adults (titer, 401 EU per milliliter) and 78% of children (titer, 828 EU per milliliter) had a response in the Ad26-MVA group; 76% (titer, 992 EU per milliliter) and 87% (titer, 1415 EU per milliliter), respectively, had a response in the rVSV group; 81% (titer, 1037 EU per milliliter) and 93% (titer, 1745 EU per milliliter), respectively, had a response in the rVSV-booster group; and 3% (titer, 93 EU per milliliter) and 4% (titer, 67 EU per milliliter), respectively, had a response in the placebo group (P<0.001 for all comparisons of vaccine with placebo). In both adults and children, antibody responses with vaccine differed from those with placebo beginning on day 14. CONCLUSIONS: No safety concerns were identified in this trial. With all three vaccine regimens, immune responses were seen from day 14 through month 12. (Funded by the National Institutes of Health and others; PREVAC ClinicalTrials.gov number, NCT02876328; EudraCT numbers, 2017-001798-18 and 2017-001798-18/3rd; and Pan African Clinical Trials Registry number, PACTR201712002760250.).


Assuntos
Vacinas contra Ebola , Ebolavirus , Doença pelo Vírus Ebola , Adulto , Criança , Humanos , Anticorpos Antivirais , República Democrática do Congo , Vacinas contra Ebola/uso terapêutico , Doença pelo Vírus Ebola/prevenção & controle
2.
Clin Infect Dis ; 78(4): 870-879, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37967326

RESUMO

BACKGROUND: The rVSVΔG-ZEBOV-GP vaccine (ERVEBO®) is a single-dose, live-attenuated, recombinant vesicular stomatitis virus vaccine indicated for the prevention of Ebola virus disease (EVD) caused by Zaire ebolavirus in individuals 12 months of age and older. METHODS: The Partnership for Research on Ebola VACcination (PREVAC) is a multicenter, phase 2, randomized, double-blind, placebo-controlled trial of 3 vaccine strategies in healthy children (ages 1-17) and adults, with projected 5 years of follow-up (NCT02876328). Using validated assays (GP-ELISA and PRNT), we measured antibody responses after 1-dose rVSVΔG-ZEBOV-GP, 2-dose rVSVΔG-ZEBOV-GP (given on Day 0 and Day 56), or placebo. Furthermore, we quantified vaccine virus shedding in a subset of children's saliva using RT-PCR. RESULTS: In total, 819 children and 783 adults were randomized to receive rVSVΔG-ZEBOV-GP (1 or 2 doses) or placebo. A single dose of rVSVΔG-ZEBOV-GP increased antibody responses by Day 28 that were sustained through Month 12. A second dose of rVSVΔG-ZEBOV-GP given on Day 56 transiently boosted antibody concentrations. In vaccinated children, GP-ELISA titers were superior to placebo and non-inferior to vaccinated adults. Vaccine virus shedding was observed in 31.7% of children, peaking by Day 7, with no shedding observed after Day 28 post-dose 1 or any time post-dose 2. CONCLUSIONS: A single dose of rVSVΔG-ZEBOV-GP induced robust antibody responses in children that was non-inferior to the responses induced in vaccinated adults. Vaccine virus shedding in children was time-limited and only observed after the first dose. Overall, these data support the use of rVSVΔG-ZEBOV-GP for the prevention of EVD in at-risk children. Clinical Trials Registration. The study is registered at ClinicalTrials.gov (NCT02876328), the Pan African Clinical Trials Registry (PACTR201712002760250), and the European Clinical Trials Register (EudraCT number: 2017-001798-18).


Assuntos
Vacinas contra Ebola , Ebolavirus , Doença pelo Vírus Ebola , Adulto , Criança , Humanos , Anticorpos Antivirais , Proteínas do Envelope Viral , Vacinas Sintéticas , Vacinação/métodos , Vacinas Atenuadas , Imunogenicidade da Vacina
3.
Chem Biodivers ; 13(6): 737-47, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27135901

RESUMO

Natural extracts used in fine fragrances (alcoholic perfumes) are rare and precious. As such, they represent an interesting target for fraudulent practices called adulterations. Absolutes, important materials used in the creation of perfumes, are obtained by organic solvent extraction of raw plant materials. Because the nonvolatile part of these natural extracts is not normalized and scarcely reported, highlighting potential adulterations present in this fraction appears highly challenging. For the first time, we investigated the use of nontargeted UHPLC-ToFMS metabolomics for this purpose, considering Viola odorata l., a plant largely used in the perfume industry, as a model. Significant differences in the metabolic fingerprints of the violet leaf absolutes were evidenced according to geographical locations, and/or adulterations. Additionally, markers of the geographical origin were detected through their molecular weight/most probable molecular formula and retention time, while adulterations were statistically validated. In this study, we thus clearly demonstrated the efficiency of UHPLC-ToFMS-based metabolomics in accelerating both the identification of the origin of raw materials as well as the search for potential adulterations in absolutes, natural products of high added value.


Assuntos
Produtos Biológicos/isolamento & purificação , Produtos Biológicos/metabolismo , Aromatizantes/metabolismo , Metabolômica , Perfumes/química , Extratos Vegetais/metabolismo , Folhas de Planta/química , Viola/química , Produtos Biológicos/química , Cromatografia Líquida de Alta Pressão , Aromatizantes/química , Aromatizantes/isolamento & purificação , Espectrometria de Massas , Conformação Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/metabolismo , Spinacia oleracea/química , Spinacia oleracea/metabolismo , Viola/metabolismo
4.
Anal Bioanal Chem ; 406(30): 8041-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25344932

RESUMO

Damascena and centifolia roses are cultivated worldwide for their petal extracts that contain key odorant ingredients of perfumes. The analytical identification and quantification of pesticides in rose petals have never been described in the literature. Here, we report on a newly developed method using dispersive solid-phase extraction (d-SPE) cleanup followed by gas chromatography-tandem mass spectrometry for the quantitative determination of multi-residue pesticides in rose petals. Analytes were extracted from the matrix using acetonitrile and a mixture of salts containing magnesium sulfate, sodium citrate, sodium chloride, and sodium sesquihydrate. Samples were cleaned up twice by d-SPE applying primary and secondary amines (PSAs), magnesium sulfate, C18, and graphitized carbon black (GCB). Two fortification levels of 0.05 and 0.5 mg kg(-1) were assessed for method validation purposes. The obtained pesticide recoveries were in the range of 70-120 % with a relative standard deviation (RSD) of less than 20 %. The newly developed method was allowed for the quantification of 57 pesticides residues. It was applied to pesticide residue detection in rose petals from an organic field, without treatment, compared to those from a field with classic phytosanitary treatment using fungicide and/or insecticide. We did not detect pesticide residues in rose petals from the organic field. The classically treated samples of roses contained pesticides such as chlorpyriphos and methidathion which are in accordance with the previous application of these pesticides on the roses. Insecticides were quantified at 0.05 mg kg(-1) rose petal maximum.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Resíduos de Praguicidas/análise , Rosa/química , Extração em Fase Sólida/métodos
5.
Anal Bioanal Chem ; 406(4): 971-80, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23797908

RESUMO

Natural extracts used by the fragrance and cosmetics industries, namely essential oils, concretes, resinoids, and absolutes, are produced from natural raw materials. These are often cultivated by use of monoculture techniques that involve the use of different classes of xenobiotica, including pesticides. Because of these pesticides' potential effect on public health and the environment, laws regarding permitted residual levels of pesticides used in cultivation of raw materials for fragrance and cosmetic products are expected to become stricter. The purpose of this review is to present and classify pesticides commonly used in the cultivation of these natural raw materials. We will summarize the most recent regulations, and discuss publications on detection of pesticides via chemical analysis of raw natural extracts. Advances in analytical chemistry for identification and quantification of pesticides will be presented, including both sample preparation and modern separation and detection techniques, and examples of the identification and quantification of individual pesticides present in natural extracts, for example essential oils, will be provided.


Assuntos
Produtos Biológicos/análise , Óleos Voláteis/análise , Praguicidas/análise , Extratos Vegetais/análise , Plantas/química , Animais , Produtos Biológicos/normas , Europa (Continente) , Humanos
6.
Chem Biodivers ; 11(6): 843-60, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24934671

RESUMO

Absolutes isolated from Viola odorata leaves, valuable materials for the flavor and fragrance industry, were studied. Violets are mainly cultivated in France and Egypt and extracted locally. The absolutes of the two origins showed different olfactory profiles both in top and heart notes, as evidenced by sensory analysis. The aims of this study were i) to characterize the volatile compounds, ii) to determine the odorant-active ones, and iii) to identify some markers of the plant origin. Two complementary analytical methods were used for these purposes, i.e., headspace solid-phase microextraction (HS-SPME) using different fiber coatings followed by GC/MS analysis and gas chromatography - olfactometry/mass spectrometry (GC-O/MS) applied to violet leaf extracts. From a total of 70 identified compounds, 61 have never been reported so far for this species, 17 compounds were characterized by both techniques (with seven among them known from the literature), 23 compounds were solely identified by HS-SPME GC/MS (among them only two being already mentioned as components of violet absolutes in the literature), and, finally, 30 compounds were only identified by GC-O/MS. According to the HS-SPME GC/MS analyses, ethyl hexanoate and (2E,6Z)-nona-2,6-dienol were specific volatile compounds of the sample with French origin, while (E,E)-hepta-2,4-dienal, hexanoic acid, limonene, tridecane, and eugenol were specific of the samples with Egyptian origin. Additional compounds that were not detected by HS-SPME GC/MS analysis were revealed by GC-O analyses, some of them being markers of origin. Pent-1-en-3-ol, 3-methylbut-2-enal, 2-methoxy-3-(1-methylethyl)pyrazine, 4-ethylbenzaldehyde, ß-phenethyl formate, and 2-methoxy-3-(2-methylpropyl)pyrazine revealed to be odorant markers of the French sample, whereas cis-rose oxide, trans-rose oxide, and 3,5,5-trimethylcyclohex-2-enone were odorant markers of the Egyptian samples.


Assuntos
Odorantes , Folhas de Planta/química , Viola/química , Compostos Orgânicos Voláteis/química , Egito , França , Compostos Orgânicos Voláteis/isolamento & purificação
7.
Trials ; 22(1): 86, 2021 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-33485369

RESUMO

INTRODUCTION: The Ebola virus disease (EVD) outbreak in 2014-2016 in West Africa was the largest on record and provided an opportunity for large clinical trials and accelerated efforts to develop an effective and safe preventative vaccine. Multiple questions regarding the safety, immunogenicity, and efficacy of EVD vaccines remain unanswered. To address these gaps in the evidence base, the Partnership for Research on Ebola Vaccines (PREVAC) trial was designed. This paper describes the design, methods, and baseline results of the PREVAC trial and discusses challenges that led to different protocol amendments. METHODS: This is a randomized, double-blind, placebo-controlled phase 2 clinical trial of three vaccine strategies against the Ebola virus in healthy volunteers 1 year of age and above. The three vaccine strategies being studied are the rVSVΔG-ZEBOV-GP vaccine, with and without a booster dose at 56 days, and the Ad26.ZEBOV,MVA-FN-Filo vaccine regimen with Ad26.ZEBOV given as the first dose and the MVA-FN-Filo vaccination given 56 days later. There have been 4 versions of the protocol with those enrolled in Version 4.0 comprising the primary analysis cohort. The primary endpoint is based on the antibody titer against the Ebola virus surface glycoprotein measured 12 months following the final injection. RESULTS: From April 2017 to December 2018, a total of 5002 volunteers were screened and 4789 enrolled. Participants were enrolled at 6 sites in four countries (Guinea, Liberia, Sierra Leone, and Mali). Of the 4789 participants, 2560 (53%) were adults and 2229 (47%) were children. Those < 18 years of age included 549 (12%) aged 1 to 4 years, 750 (16%) 5 to 11 years, and 930 (19%) aged 12-17 years. At baseline, the median (25th, 75th percentile) antibody titer to Ebola virus glycoprotein for 1090 participants was 72 (50, 116) EU/mL. DISCUSSION: The PREVAC trial is evaluating-placebo-controlled-two promising Ebola candidate vaccines in advanced stages of development. The results will address unanswered questions related to short- and long-term safety and immunogenicity for three vaccine strategies in adults and children. TRIAL REGISTRATION: ClinicalTrials.gov NCT02876328 . Registered on 23 August 2016.


Assuntos
Vacinas contra Ebola , Doença pelo Vírus Ebola , Adulto , África Ocidental , Criança , Pré-Escolar , Ensaios Clínicos Fase II como Assunto , Método Duplo-Cego , Vacinas contra Ebola/efeitos adversos , Voluntários Saudáveis , Doença pelo Vírus Ebola/prevenção & controle , Humanos , Lactente , Ensaios Clínicos Controlados Aleatórios como Assunto , Vacinação
8.
Anal Chim Acta ; 992: 55-66, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29054150

RESUMO

In this paper is described for the first time the application of both gas chromatography-tandem mass spectrometry (GC-MS/MS) and ultra performance liquid chromatography-quadrupole-time of flight-mass spectrometry (UPLC-QTOF-MS) to the determination of 75 priority pesticides in orange essential oils (EOs). The sample preparation consisted in a 10-fold dilution of orange EO followed by a direct injection for GC-MS/MS technique and a freeze-out step in the case of UPLC-QTOF-MS analysis. The analytical methods were validated using the SANCO criteria and gave reporting limits (RLs) of 10 µg L-1, 25 µg L-1, 50 µg L-1 and 100 µg L-1 for 57, 13, 4 and 1 pesticides, respectively. The analysis of four others EOs in the context of a proficiency test demonstrated very good performance and versatility of the methods with a detection rate of 100%, 97.8% of correct quantifications and no false negative. Then 49 orange EOs of known origin and quality were analysed using the standard addition procedure. It enabled to highlight significant matrix effects leading to differences in response factor up to 9.0 in GC-MS/MS and 53.1 in UPLC-QTOF-MS, between an orange EO sample to another. It was found that a conventional EO contained on average 17 pesticides for a total concentration of 5.1 mg L-1. Up to 29 different pesticides, 39 in the case of a concentrated EO, were detected in one sample and the sum of the concentration reached 51.1 mg L-1. Regarding the organic samples, none were free of pesticides but the contamination was found to be clearly lower than in conventional EOs. It was found that an organic orange EO contained on average 4 pesticides for a total concentration of 0.087 mg L-1.


Assuntos
Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Óleos Voláteis/análise , Resíduos de Praguicidas/análise , Citrus sinensis/química , Óleos de Plantas/análise , Espectrometria de Massas em Tandem
10.
J Agric Food Chem ; 63(20): 4922-32, 2015 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-25942486

RESUMO

This study investigates the concentrations of 54 multiclass pesticides during the transformation processes from rose petal to concrete and absolute using roses spiked with pesticides as a model. The concentrations of the pesticides were followed during the process of transforming the spiked rose flowers from an organic field into concrete and then into absolute. The rose flowers, the concrete, and the absolute, as well as their transformation intermediates, were analyzed for pesticide content using gas chromatography/tandem mass spectrometry. We observed that all the pesticides were extracted and concentrated in the absolute, with the exception of three molecules: fenthion, fenamiphos, and phorate. Typical pesticides were found to be concentrated by a factor of 100-300 from the rose flowers to the rose absolute. The observed effect of pesticide enrichment was also studied in roses and their extracts from four classically phytosanitary treated fields. Seventeen pesticides were detected in at least one of the extracts. Like the case for the spiked samples in our model, the pesticides present in the rose flowers from Turkey were concentrated in the absolute. Two pesticides, methidathion and chlorpyrifos, were quantified in the rose flowers at approximately 0.01 and 0.01-0.05 mg kg(-1), respectively, depending on the treated field. The concentrations determined for the corresponding rose absolutes were 4.7 mg kg(-1) for methidathion and 0.65-27.25 mg kg(-1) for chlorpyrifos.


Assuntos
Perfumes/análise , Resíduos de Praguicidas/química , Rosa/química , Flores/química , Cromatografia Gasosa-Espectrometria de Massas
11.
AIDS ; 27(10): 1671-4, 2013 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-23595155

RESUMO

We report the first transmitted drug resistance survey study in HIV-2-infected patients living in France. The prevalence of transmitted drug resistance was 5.0% (95% confidence interval, 0.1-9.9) with mutations detected only in protease, not in reverse transcriptase. In this series, 10% of patients displayed X4/dual-mixed viruses. These findings classified the rate of transmitted drug resistance in the HIV-2 French Cohort as low prevalence.


Assuntos
Farmacorresistência Viral/genética , Infecções por HIV/virologia , HIV-2/genética , França/epidemiologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Inibidores da Protease de HIV/farmacologia , HIV-2/efeitos dos fármacos , Humanos , Prevalência , RNA Viral/genética , Inibidores da Transcriptase Reversa/farmacologia
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