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1.
Emerg Infect Dis ; 28(3): 734-738, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35202536

RESUMO

We explored the association of Ebola virus antibody seropositivity and concentration with potential risk factors for infection. Among 1,282 adults and children from a community affected by the 2014-2016 Ebola outbreak in Sierra Leone, 8% were seropositive for virus antibodies but never experienced disease symptoms. Antibody concentration increased with age.


Assuntos
Ebolavirus , Doença pelo Vírus Ebola , Adulto , Criança , Surtos de Doenças , Glicoproteínas , Doença pelo Vírus Ebola/epidemiologia , Humanos , Imunoglobulina G , Estudos Soroepidemiológicos , Serra Leoa/epidemiologia
2.
Molecules ; 27(2)2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-35056658

RESUMO

The supply of nutrients, such as antioxidant agents, to fish cells still represents a challenge in aquaculture. In this context, we investigated solid lipid nanoparticles (SLN) composed of a combination of Gelucire® 50/13 and Precirol® ATO5 to administer a grape seed extract (GSE) mixture containing several antioxidant compounds. The combination of the two lipids for the SLN formation resulted in colloids exhibiting mean particle sizes in the range 139-283 nm and zeta potential values in the range +25.6-43.4 mV. Raman spectra and X-ray diffraction evidenced structural differences between the free GSE and GSE-loaded SLN, leading to the conclusion that GSE alters the structure of the lipid nanocarriers. From a biological viewpoint, cell lines from gilthead seabream and European sea bass were exposed to different concentrations of GSE-SLN for 24 h. In general, at appropriate concentrations, GSE-SLN increased the viability of the fish cells. Furthermore, regarding the gene expression in those cells, the expression of antioxidant genes was upregulated, whereas the expression of hsp70 and other genes related to the cytoskeleton was downregulated. Hence, an SLN formulation containing Gelucire® 50/13/Precirol® ATO5 and GSE may represent a compelling platform for improving the viability and antioxidant properties of fish cells.


Assuntos
Antioxidantes/administração & dosagem , Proteínas de Peixes/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Extrato de Sementes de Uva/administração & dosagem , Lipossomos/administração & dosagem , Nanopartículas/administração & dosagem , Polifenóis/administração & dosagem , Vitis/química , Animais , Antioxidantes/farmacologia , Aquicultura , Proteínas de Peixes/genética , Peixes , Extrato de Sementes de Uva/farmacologia , Lipossomos/química , Nanopartículas/química , Estresse Oxidativo , Polifenóis/farmacologia
3.
Int J Mol Sci ; 22(4)2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33670800

RESUMO

Copper (Cu) dyshomeostasis plays a pivotal role in several neuropathologies, such as Parkinson's disease (PD). Metal accumulation in the central nervous system (CNS) could result in loss-of-function of proteins involved in Cu metabolism and redox cycling, generating reactive oxygen species (ROS). Moreover, neurodegenerative disorders imply the presence of an excess of misfolded proteins known to lead to neuronal damage. In PD, Cu accumulates in the brain, binds α-synuclein, and initiates its aggregation. We assessed the correlation between neuronal differentiation, Cu homeostasis regulation, and α-synuclein phosphorylation. At this purpose, we used differentiated SHSY5Y neuroblastoma cells to reproduce some of the characteristics of the dopaminergic neurons. Here, we reported that differentiated cells expressed a significantly higher amount of a copper transporter protein 1 (CTR1), increasing the copper uptake. Cells also showed a significantly more phosphorylated form of α-synuclein, further increased by copper treatment, without modifications in α-synuclein levels. This effect depended on the upregulation of the polo-like kinase 2 (PLK2), whereas the levels of the relative protein phosphatase 2A (PP2A) remained unvaried. No changes in the oxidative state of the cells were identified. The Cu dependent alteration of α-synuclein phosphorylation pattern might potentially offer new opportunities for clinical intervention.


Assuntos
Cobre/metabolismo , Neuroblastoma/metabolismo , Neuroblastoma/patologia , alfa-Sinucleína/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cobre/farmacologia , Proteínas de Transporte de Cobre/genética , Proteínas de Transporte de Cobre/metabolismo , ATPases Transportadoras de Cobre/genética , ATPases Transportadoras de Cobre/metabolismo , Humanos , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo
4.
Molecules ; 26(4)2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33572331

RESUMO

Background: The loss of nigrostriatal neurons containing dopamine (DA) together with the "mitochondrial dysfunction" in midbrain represent the two main causes related to the symptoms of Parkinson's disease (PD). Hence, the aim of this investigation is to co-administer the missing DA and the antioxidant grape seed-derived proanthocyanidins (grape seed extract, GSE) in order to increase the levels of the neurotransmitter (which is unable to cross the Blood Brain Barrier) and reducing the oxidative stress (OS) related to PD, respectively. Methods: For this purpose, we chose Solid Lipid Nanoparticles (SLN), because they have been already proven to increase DA uptake in the brain. DA-SLN adsorbing GSE (GSE/DA-SLN) were formulated and subjected to physico-chemical characterization, and their cytocompatibility and protection against OS were examined. Results: GSE was found on SLN surface and release studies evidenced the efficiency of GSE in preventing DA autoxidation. Furthermore, SLN showed high mucoadhesive strength and were found not cytotoxic to both primary Olfactory Ensheathing and neuroblastoma SH-SY5Y cells by MTT test. Co-administration of GSE/DA-SLN and the OS-inducing neurotoxin 6-hydroxydopamine (100 µM) resulted in an increase of SH-SY5Y cell viability. Conclusions: Hence, SLN formulations containing DA and GSE may constitute interesting candidates for non-invasive nose-to-brain delivery.


Assuntos
Antioxidantes/farmacologia , Citoproteção , Dopamina/farmacologia , Extrato de Sementes de Uva/farmacologia , Nanopartículas/administração & dosagem , Neuroblastoma/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Proantocianidinas/farmacologia , Sobrevivência Celular , Dopaminérgicos/farmacologia , Quimioterapia Combinada , Humanos , Nanopartículas/química , Células Tumorais Cultivadas , Vitis/química
5.
J Infect Dis ; 220(1): 46-56, 2019 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-30796818

RESUMO

BACKGROUND: Ebola vaccine development was accelerated in response to the 2014 Ebola virus infection outbreak. This phase 1 study (VAC52150EBL1004) assessed safety, tolerability, and immunogenicity of heterologous 2-dose Ad26.ZEBOV, MVA-BN-Filo vaccination regimens in the Lake Victoria Basin of Tanzania and Uganda in mid-level altitude, malaria-endemic settings. METHODS: Healthy volunteers aged 18-50 years from Tanzania (n = 25) and Uganda (n = 47) were randomized to receive placebo or active vaccination with Ad26.ZEBOV or MVA-BN-Filo (first vaccination), followed by MVA-BN-Filo or Ad26.ZEBOV (second vaccination) dose 2, respectively, with intervals of 28 or 56 days. RESULTS: Seventy-two adults were randomized to receive vaccine (n = 60) or placebo (n = 12). No vaccine-related serious adverse events were reported. The most frequent solicited local and systemic adverse events were injection site pain (frequency, 70%, 66%, and 42% per dose for MVA-BN-Filo, Ad26.ZEBOV, and placebo, respectively) and headache (57%, 56%, and 46%, respectively). Adverse event patterns were similar among regimens. Twenty-one days after dose 2, 100% of volunteers demonstrated binding antibody responses against Ebola virus glycoprotein, and 87%-100% demonstrated neutralizing antibody responses. Ad26.ZEBOV dose 1 vaccination induced more-robust initial binding antibody and cellular responses than MVA-BN-Filo dose 1 vaccination. CONCLUSIONS: Heterologous 2-dose vaccination with Ad26.ZEBOV and MVA-BN-Filo against Ebola virus is well tolerated and immunogenic in healthy volunteers. CLINICAL TRIALS REGISTRATION: NCT02376400.


Assuntos
Formação de Anticorpos/imunologia , Vacinas contra Ebola/efeitos adversos , Vacinas contra Ebola/imunologia , Ebolavirus/imunologia , Doença pelo Vírus Ebola/imunologia , Vacinas Virais/imunologia , Adolescente , Adulto , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Surtos de Doenças/prevenção & controle , Feminino , Voluntários Saudáveis , Doença pelo Vírus Ebola/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Tanzânia , Uganda , Vacinação/efeitos adversos , Vacinas de DNA , Vacinas Virais/efeitos adversos , Adulto Jovem
7.
Clin Trials ; 15(5): 436-443, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29895178

RESUMO

Background/aims During the 2014-2016 West African Ebola epidemic, clinical trials were fast-tracked in order to identify prophylactic vaccines and experimental treatments that might be useful in preventing or treating Ebola. These trials included the ongoing EBOVAC-Salone study, which was established and implemented in Sierra Leone to assess the safety and immunogenicity of the Ad26.ZEBOV/MVA-BN-Filo prime-boost Ebola vaccine regimen. Methods This article describes the experiences of the EBOVAC-Salone research team in setting up and implementing the trial, and provides recommendations for research teams aiming to conduct clinical trials in future outbreak situations. Results Establishing a clinical trial during an outbreak brought some unique challenges, including those related to trial design and the regulatory environment, operational issues, and community engagement. The situation was further complicated by the weak infrastructure and limited experience of clinical trials in Sierra Leone. However, operating in an outbreak context also brought some benefits to the research team, including strong stakeholder support. The EBOVAC-Salone study recruited participants both during and after the outbreak, leading to additional challenges to trial implementation during the post-outbreak transition. Conclusion Many lessons have been learned about setting up and implementing a clinical trial during a devastating Ebola epidemic, and some of the experiences of the EBOVAC-Salone team were mirrored by those of other researchers operating in the region. Common to several of these research groups is a recommendation that research should be more closely incorporated into outbreak response planning, which could expedite the establishment of timely and appropriate research projects. We recommend that the lessons learned by researchers during the West African Ebola epidemic are built into programmes and strategies to improve the responses to future epidemics, wherever they occur.


Assuntos
Ensaios Clínicos como Assunto , Vacinas contra Ebola/imunologia , Adulto , Epidemias/prevenção & controle , Feminino , Doença pelo Vírus Ebola/epidemiologia , Humanos , Masculino , Seleção de Pacientes , Serra Leoa/epidemiologia
8.
BMC Med ; 13: 17, 2015 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-25630368

RESUMO

BACKGROUND: Malnourished HIV-infected African adults are at high risk of early mortality after starting antiretroviral therapy (ART). We hypothesized that short-course, high-dose vitamin and mineral supplementation in lipid nutritional supplements would decrease mortality. METHODS: The study was an individually-randomised phase III trial conducted in ART clinics in Mwanza, Tanzania, and Lusaka, Zambia. Participants were 1,815 ART-naïve non-pregnant adults with body mass index (BMI) <18.5 kg/m² who were referred for ART based on CD4 count <350 cells/µL or WHO stage 3 or 4 disease. The intervention was a lipid-based nutritional supplement either without (LNS) or with additional vitamins and minerals (LNS-VM), beginning prior to ART initiation; supplement amounts were 30 g/day (150 kcal) from recruitment until 2 weeks after starting ART and 250 g/day (1,400 kcal) from weeks 2 to 6 after starting ART. The primary outcome was mortality between recruitment and 12 weeks of ART. Secondary outcomes were serious adverse events (SAEs) and abnormal electrolytes throughout, and BMI and CD4 count at 12 weeks ART. RESULTS: Follow-up for the primary outcome was 91%. Median adherence was 66%. There were 181 deaths in the LNS group (83.7/100 person-years) and 184 (82.6/100 person-years) in the LNS-VM group (rate ratio (RR), 0.99; 95% CI, 0.80-1.21; P = 0.89). The intervention did not affect SAEs or BMI, but decreased the incidence of low serum phosphate (RR, 0.73; 95% CI, 0.55-0.97; P = 0.03) and increased the incidence of high serum potassium (RR, 1.60; 95% CI, 1.19-2.15; P = 0.002) and phosphate (RR, 1.23; 95% CI, 1.10-1.37; P <0.001). Mean CD4 count at 12 weeks post-ART was 25 cells/µL (95% CI, 4-46) higher in the LNS-VM compared to the LNS arm (P = 0.02). CONCLUSIONS: High-dose vitamin and mineral supplementation in LNS, compared to LNS alone, did not decrease mortality or clinical SAEs in malnourished African adults initiating ART, but improved CD4 count. The higher frequency of elevated serum potassium and phosphate levels suggests high-level electrolyte supplementation for all patients is inadvisable but the addition of micronutrient supplements to ART may provide clinical benefits in these patients. TRIAL REGISTRATION: PACTR201106000300631, registered on 1st June 2011.


Assuntos
Antirretrovirais/uso terapêutico , Suplementos Nutricionais , Infecções por HIV/mortalidade , Desnutrição/dietoterapia , Vitaminas/administração & dosagem , Adulto , Índice de Massa Corporal , Contagem de Linfócito CD4 , Eletrólitos/sangue , Feminino , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Masculino , Desnutrição/complicações , Pessoa de Meia-Idade , Tanzânia , Zâmbia
9.
Crit Care ; 18(6): 685, 2014 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-25498484

RESUMO

INTRODUCTION: To investigate the mechanism of action of tranexamic acid (TXA) in bleeding trauma patients, we examined the timing of its effect on mortality. We hypothesised that if TXA reduces mortality by decreasing blood loss, its effect should be greatest on the day of the injury when bleeding is most profuse. However, if TXA reduces mortality via an anti-inflammatory mechanism its effect should be greater over the subsequent days. METHODS: Exploratory analysis, including per-protocol analyses, of data from the CRASH-2 trial, a randomised placebo controlled trial of the effect of TXA on mortality in 20,211 trauma patients with, or at risk of, significant bleeding. We examined hazard ratios (HR) and 95% confidence intervals for all-cause mortality, deaths due to bleeding and non-bleeding deaths, according to the day since injury. The CRASH-2 trial is registered as ISRCTN86750102 and ClinicalTrials.gov NCT00375258. RESULTS: The effect of TXA on mortality is greatest for deaths occurring on the day of the injury (HR all-cause mortality = 0.83, 0.73 to 0.93). This survival benefit is only evident in patients in whom treatment is initiated within 3 hours of their injury (HR ≤ 3 hours = 0.78, 0.68 to 0.90; HR > 3 hours = 1.02, 0.76 to 1.36). Initiation of TXA treatment within 3 hours of injury reduced the hazard of death due to bleeding on the day of the injury by 28% (HR = 0.72, 0.60 to 0.86). TXA treatment initiated beyond 3 hours of injury appeared to increase the hazard of death due to bleeding, although the estimates were imprecise. CONCLUSIONS: Early administration of tranexamic acid appears to reduce mortality primarily by preventing exsanguination on the day of the injury.


Assuntos
Antifibrinolíticos/uso terapêutico , Causas de Morte/tendências , Hemorragia/tratamento farmacológico , Hemorragia/mortalidade , Traumatismo Múltiplo/tratamento farmacológico , Traumatismo Múltiplo/mortalidade , Estatística como Assunto , Ácido Tranexâmico/uso terapêutico , Exsanguinação/diagnóstico , Exsanguinação/tratamento farmacológico , Exsanguinação/mortalidade , Feminino , Hemorragia/diagnóstico , Humanos , Masculino , Mortalidade/tendências , Traumatismo Múltiplo/diagnóstico , Estatística como Assunto/métodos
10.
Vaccines (Basel) ; 12(2)2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38400193

RESUMO

In this prospective, observational study (ClinicalTrials.gov Identifier: NCT02661464), long-term safety information was collected from participants previously exposed to the Ebola vaccines Ad26.ZEBOV and/or MVA-BN-Filo while enrolled in phase 1, 2, or 3 clinical studies. The study was conducted at 15 sites in seven countries (Burkina Faso, France, Kenya, Tanzania, Uganda, the United Kingdom, and the United States). Adult participants and offspring from vaccinated female participants who became pregnant (estimated conception ≤28 days after vaccination with MVA-BN-Filo or ≤3 months after vaccination with Ad26.ZEBOV) were enrolled. Adults were followed for 60 months after their first vaccination, and children born to female participants were followed for 60 months after birth. In the full analysis set (n = 614 adults; median age [range]: 32.0 [18-65] years), 49 (8.0%) had ≥1 serious adverse event (SAE); the incidence rate of any SAE was 27.4 per 1000 person-years (95% confidence interval: 21.0, 35.2). The unrelated SAEs of malaria were reported in the two infants in the full analysis set, aged 11 and 18 months; both episodes were resolved. No deaths or life-threatening SAEs occurred during the study. Overall, no major safety issues were identified; one related SAE was reported. These findings support the long-term clinical safety of the Ad26.ZEBOV and MVA-BN-Filo vaccines.

11.
RSC Adv ; 14(20): 14126-14138, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38686287

RESUMO

Magnetic nanocomposites (MNC) are promising theranostic platforms with tunable physicochemical properties allowing for remote drug delivery and multimodal imaging. Here, we developed doxorubicin-loaded Fe3O4-Au MNC (DOX-MNC) using electron beam physical vapor deposition (EB-PVD) in combination with magneto-mechanochemical synthesis to assess their antitumor effect on Walker-256 carcinosarcoma under the influence of a constant magnetic (CMF) and electromagnetic field (EMF) by comparing tumor growth kinetics, magnetic resonance imaging (MRI) scans and electron spin resonance (ESR) spectra. Transmission (TEM) and scanning electron microscopy (SEM) confirmed the formation of spherical magnetite nanoparticles with a discontinuous gold coating that did not significantly affect the ferromagnetic properties of MNC, as measured by vibrating-sample magnetometry (VSM). Tumor-bearing animals were divided into the control (no treatment), conventional doxorubicin (DOX), DOX-MNC and DOX-MNC + CMF + EMF groups. DOX-MNC + CMF + EMF resulted in 14% and 16% inhibition of tumor growth kinetics as compared with DOX and DOX-MNC, respectively. MRI visualization showed more substantial tumor necrotic changes after the combined treatment. Quantitative analysis of T2-weighted (T2W) images revealed the lowest value of skewness and a significant increase in tumor intensity in response to DOX-MNC + CMF + EMF as compared with the control (1.4 times), DOX (1.6 times) and DOX-MNC (1.8 times) groups. In addition, the lowest level of nitric oxide determined by ESR was found in DOX-MNC + CMF + EMF tumors, which was close to that of the muscle tissue in the contralateral limb. We propose that the reason for the relationship between the observed changes in MRI and ESR is the hyperfine interaction of nuclear and electron spins in mitochondria, as a source of free radical production. Therefore, these results point to the use of EB-PVD and magneto-mechanochemically synthesized Fe3O4-Au MNC loaded with DOX as a potential candidate for cancer magnetic nanotheranostic applications.

12.
Biomed Microdevices ; 15(2): 299-309, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23239124

RESUMO

Surfactant nanocarriers have received considerable attention in the last several years as interesting alternative to classic liposomes. Different pH-sensitive vesicular colloidal carriers based on Tween 20 derivatives, obtained after functionalization of the head groups of the surfactant with natural, or simply modified, amino acids, were proposed as drug nanocarriers. Dynamic light scattering, Small Angle X-ray Scattering, Trasmission Electron Microscopy and fluorescence studies were used for the physico-chemical characterization of vesicles and mean size, size distribution, zeta potential, vesicle morphology and bilayer properties were evaluated. The pH-sensitivity and the stability of formulations, in absence and in presence of foetal bovine serum, were also evaluated. Moreover, the contact between surfactant vesicles and liposomes designed to model the cellular membrane was investigated by fluorescence studies to preliminary explore the potential interaction between vesicle and cell membranes. Experimental findings showed that physico-chemical and technological features of pH-sensitive vesicles were influenced by the composition of the carriers. Furthermore, proposed carriers are able to interact with mimetic cell membrane and it is reasonable to attribute the observed differences in interaction to the architectural/structural properties of Tween 20 derivatives. The findings reported in this investigation showed that a deep and extensive physico-chemical characterization of the carrier is a fundamental step, according to the evidence that the knowledge of nanocarrier properties is necessary to translate its potentiality to in vitro/in vivo applications.


Assuntos
Materiais Biomiméticos/química , Membrana Celular/química , Concentração de Íons de Hidrogênio , Lipossomos/química , Nanocápsulas/química , Tensoativos/química , Teste de Materiais , Nanocápsulas/ultraestrutura , Fosfolipídeos/química
13.
Vaccines (Basel) ; 11(8)2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37631885

RESUMO

We assessed whether the immunogenicity of the two-dose Ad26.ZEBOV, MVA-BN-Filo Ebola vaccine regimen with a 56-day interval between doses was affected by exposure to malaria before dose 1 vaccination and by clinical episodes of malaria in the period immediately after dose 1 and after dose 2 vaccinations. Previous malaria exposure in participants in an Ebola vaccine trial in Sierra Leone (ClinicalTrials.gov: NCT02509494) was classified as low, intermediate, and high according to their antibody responses to a panel of Plasmodium falciparum antigens detected using a Luminex MAGPIX platform. Clinical malaria episodes after vaccinations were recorded as part of the trial safety monitoring. Binding antibody responses against the Ebola virus (EBOV) glycoprotein (GP) were measured 57 days post dose 1 and 21 days post dose 2 by ELISA and summarized as Geometric Mean Concentrations (GMCs). Geometric Mean Ratios (GMRs) were used to compare groups with different levels of exposure to malaria. Overall, 587 participants, comprising 188 (32%) adults (aged ≥ 18 years) and 399 (68%) children (aged 1-3, 4-11, and 12-17 years), were included in the analysis. There was no evidence that the anti-EBOV-GP antibody GMCs post dose 1 and post dose 2 differed between categories of previous malaria exposure. There was weak evidence that the GMC at 57 days post dose 1 was lower in participants who had had at least one episode of clinical malaria post dose 1 compared to participants with no diagnosed clinical malaria in the same period (GMR = 0.82, 95% CI: 0.69-0.98, p-value = 0.02). However, GMC post dose 2 was not reduced in participants who experienced clinical malaria post-dose 1 and/or post-dose 2 vaccinations. In conclusion, the Ad26.ZEBOV, MVA-BN-Filo Ebola vaccine regimen is immunogenic in individuals with previous exposure to malaria and in those who experience clinical malaria after vaccination. This vaccine regimen is suitable for prophylaxis against Ebola virus disease in malaria-endemic regions.

14.
Vaccine ; 41(50): 7573-7580, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-37981473

RESUMO

BACKGROUND: People living with HIV constitute an important part of the population in regions at risk of Ebola virus disease outbreaks. The two-dose Ad26.ZEBOV, MVA-BN-Filo Ebola vaccine regimen induces strong immune responses in HIV-positive (HIV+) adults but the durability of this response is unknown. It is also unclear whether this regimen can establish immune memory to enable an anamnestic response upon re-exposure to antigen. METHODS: This paper describes an open-label, phase 2 trial, conducted in Kenya and Uganda, of Ad26.ZEBOV booster vaccination in HIV+ participants who had previously received the Ad26.ZEBOV, MVA-BN-Filo primary regimen. HIV+ adults with well-controlled infection and on highly active antiretroviral therapy were enrolled, vaccinated with booster, and followed for 28 days. The primary objectives were to assess Ad26.ZEBOV booster safety and antibody responses against the Ebola virus glycoprotein using the Filovirus Animal Non-Clinical Group ELISA. RESULTS: The Ad26.ZEBOV booster was well-tolerated in HIV+ adults with mostly mild to moderate symptoms. No major safety concerns or serious adverse events were reported. Four and a half years after the primary regimen, 24/26 (92 %) participants were still classified as responders, with a pre-booster antibody geometric mean concentration (GMC) of 726 ELISA units (EU)/mL (95 %CI 447-1179). Seven days after the booster, the GMC increased 54-fold to 38,965 EU/mL (95 %CI 23532-64522). Twenty-one days after the booster, the GMC increased 176-fold to 127,959 EU/mL (95 %CI 93872-174422). The responder rate at both post-booster time points was 100 %. CONCLUSIONS: The Ad26.ZEBOV booster is safe and highly immunogenic in HIV+ adults with well-controlled infection. The Ad26.ZEBOV, MVA-BN-Filo regimen can generate long-term immune memory persisting for at least 4·5 years, resulting in a robust anamnestic response. TRIAL REGISTRATION: Pan African Clinical Trial Registry (PACTR202102747294430). CLINICALTRIALS: gov (NCT05064956).


Assuntos
Vacinas contra Ebola , Ebolavirus , Infecções por HIV , Doença pelo Vírus Ebola , Adulto , Humanos , Anticorpos Antivirais , HIV , Infecções por HIV/tratamento farmacológico , Imunogenicidade da Vacina , Quênia , Uganda , Vaccinia virus
15.
Lancet Infect Dis ; 23(3): 352-360, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36273490

RESUMO

BACKGROUND: Children account for a substantial proportion of cases and deaths during Ebola virus disease outbreaks. We aimed to evaluate the safety and immunogenicity of a booster dose of the Ad26.ZEBOV vaccine in children who had been vaccinated with a two-dose regimen comprising Ad26.ZEBOV as dose one and MVA-BN-Filo as dose two. METHODS: We conducted an open-label, non-randomised, phase 2 trial at one clinic in Kambia Town, Sierra Leone. Healthy children, excluding pregnant or breastfeeding girls, who had received the Ad26.ZEBOV and MVA-BN-Filo vaccine regimen in a previous study, and were aged 1-11 years at the time of their first vaccine dose, received an intramuscular injection of Ad26.ZEBOV (5 × 1010 viral particles) and were followed up for 28 days. Primary outcomes were safety (measured by adverse events) and immunogenicity (measured by Ebola virus glycoprotein-specific IgG binding antibody geometric mean concentration) of the booster vaccine dose. Safety was assessed in all participants who received the booster vaccination; immunogenicity was assessed in all participants who received the booster vaccination, had at least one evaluable sample after the booster, and had no major protocol deviations that could have influenced the immune response. This trial is registered with ClinicalTrials.gov, NCT04711356. FINDINGS: Between July 8 and Aug 18, 2021, 58 children were assessed for eligibility and 50 (27 aged 4-7 years and 23 aged 9-15 years) were enrolled and received an Ad26.ZEBOV booster vaccination, more than 3 years after receiving dose one of the Ad26.ZEBOV and MVA-BN-Filo vaccine regimen. The booster was well tolerated. The most common solicited local adverse event during the 7 days after vaccination was injection site pain, reported in 18 (36%, 95% CI 23-51) of 50 participants. The most common solicited systemic adverse event during the 7 days after vaccination was headache, reported in 11 (22%, 12-36) of 50 participants. Malaria was the most common unsolicited adverse event during the 28 days after vaccination, reported in 25 (50%, 36-64) of 50 participants. No serious adverse events were observed during the study period. 7 days after vaccination, the Ebola virus glycoprotein-specific IgG binding antibody geometric mean concentration was 28 561 ELISA units per mL (95% CI 20 255-40 272), which was 44 times higher than the geometric mean concentration before the booster dose. 21 days after vaccination, the geometric mean concentration reached 64 690 ELISA units per mL (95% CI 48 356-86 541), which was 101 times higher than the geometric mean concentration before the booster dose. INTERPRETATION: A booster dose of Ad26.ZEBOV in children who had received the two-dose Ad26.ZEBOV and MVA-BN-Filo vaccine regimen more than 3 years earlier was well tolerated and induced a rapid and robust increase in binding antibodies against Ebola virus. These findings could inform Ebola vaccination strategies in paediatric populations. FUNDING: Innovative Medicines Initiative 2 Joint Undertaking. TRANSLATION: For the French translation of the abstract see Supplementary Materials section.


Assuntos
Vacinas contra Ebola , Ebolavirus , Doença pelo Vírus Ebola , Feminino , Humanos , Criança , Doença pelo Vírus Ebola/prevenção & controle , Anticorpos Antivirais , Vaccinia virus , Glicoproteínas , Imunoglobulina G , Imunogenicidade da Vacina
16.
Lancet Glob Health ; 11(11): e1743-e1752, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37858585

RESUMO

BACKGROUND: This study assessed the safety and immunogenicity of the Ad26.ZEBOV and MVA-BN-Filo Ebola virus (EBOV) vaccine regimen in infants aged 4-11 months in Guinea and Sierra Leone. METHODS: In this phase 2, randomised, double-blind, active-controlled trial, we randomly assigned healthy infants (1:1 in a sentinel cohort, 5:2 for the remaining infants via an interactive web response system) to receive Ad26.ZEBOV followed by MVA-BN-Filo (Ebola vaccine group) or two doses of meningococcal quadrivalent conjugate vaccine (control group) administered 56 days apart. Infants were recruited at two sites in west Africa: Conakry, Guinea, and Kambia, Sierra Leone. All infants received the meningococcal vaccine 8 months after being randomly assigned. The primary objective was safety. The secondary objective was immunogenicity, measured as EBOV glycoprotein-binding antibody concentration 21 days post-dose 2, using the Filovirus Animal Non-Clinical Group ELISA. This study is registered with ClinicalTrials.gov (NCT03929757) and the Pan African Clinical Trials Registry (PACTR201905827924069). FINDINGS: From Aug 20 to Nov 29, 2019, 142 infants were screened and 108 were randomly assigned (Ebola vaccine n=75; control n=33). The most common solicited local adverse event was injection-site pain (Ebola vaccine 15 [20%] of 75; control four [12%] of 33). The most common solicited systemic adverse events with the Ebola vaccine were irritability (26 [35%] of 75), decreased appetite (18 [24%] of 75), pyrexia (16 [21%] of 75), and decreased activity (15 [20%] of 75). In the control group, ten (30%) of 33 had irritability, seven (21%) of 33 had decreased appetite, three (9%) of 33 had pyrexia, and five (15%) of 33 had decreased activity. The frequency of unsolicited adverse events was 83% (62 of 75 infants) in the Ebola vaccine group and 85% (28 of 33 infants) in the control group. No serious adverse events were vaccine-related. In the Ebola vaccine group, EBOV glycoprotein-binding antibody geometric mean concentrations (GMCs) at 21 days post-dose 2 were 27 700 ELISA units (EU)/mL (95% CI 20 477-37 470) in infants aged 4-8 months and 20 481 EU/mL (15 325-27 372) in infants aged 9-11 months. The responder rate was 100% (74 of 74 responded). In the control group, GMCs for both age groups were less than the lower limit of quantification and the responder rate was 3% (one of 33 responded). INTERPRETATION: Ad26.ZEBOV and MVA-BN-Filo was well tolerated and induced strong humoral responses in infants younger than 1 year. There were no safety concerns related to vaccination. FUNDING: Janssen Vaccines & Prevention and Innovative Medicines Initiative 2 Joint Undertaking. TRANSLATION: For the French translation of the abstract see Supplementary Materials section.


Assuntos
Vacinas contra Ebola , Ebolavirus , Doença pelo Vírus Ebola , Animais , Humanos , Lactente , Vacinas contra Ebola/efeitos adversos , Doença pelo Vírus Ebola/prevenção & controle , Serra Leoa , Guiné , Anticorpos Antivirais , Método Duplo-Cego , Glicoproteínas , Febre
17.
Cell Mol Neurobiol ; 32(6): 989-1001, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22362149

RESUMO

Copper transporter 1 (CTR1), cellular prion protein (PrP(C)), natural resistance-associated macrophage protein 2 (NRAMP2) and ATP7A proteins control the cell absorption and efflux of copper (Cu) ions in nervous tissues upon physiological conditions. Little is known about their regulation under reduced Cu availability, a condition underlying the onset of diffused neurodegenerative disorders. In this study, rat neuron-like cells were exposed to Cu starvation for 48 h. The activation of Caspase-3 enzymes and the impairment of Cu,Zn superoxide dismutase (Cu,Zn SOD) activity depicted the initiation of a pro-apoptotic program, preliminary to the appearance of the morphological signs of apoptosis. The transcriptional response related to Cu transport proteins has been investigated. Notably, PrP(C) transcript and protein levels were consistently elevated upon Cu deficiency. The CTR1 protein amount was stable, despite a two-fold increase in the transcript amount, meaning the activation of post-translational regulatory mechanisms. NRAMP2 and ATP7A expressions were unvaried. The up-regulated PrP(C) has been demonstrated to enhance the cell Cu uptake ability by about 50% with respect to the basal transport, and so sustain the Cu delivery to the Cu,Zn SOD cuproenzymes. Conclusively, the study suggests a pivotal role for PrP(C) in the cell adaptation to Cu limitation through a direct activity of ion uptake. In this view, the PrP(C) accumulation observed in several cancer cell lines could be interpreted as a molecular marker of cell Cu deficiency and a potential target of therapeutic interventions against disorders caused by metal imbalances.


Assuntos
Cobre/deficiência , Neurônios/metabolismo , Príons/metabolismo , Adaptação Fisiológica/efeitos dos fármacos , Animais , Caspase 3/metabolismo , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Linhagem Celular Tumoral , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quelantes/farmacologia , Cobre/metabolismo , Ativação Enzimática/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Transporte de Íons/efeitos dos fármacos , Íons , Ferro/metabolismo , Cinética , Microscopia de Força Atômica , Neurônios/efeitos dos fármacos , Neurônios/enzimologia , Ratos , Espectrofotometria Atômica , Superóxido Dismutase/metabolismo , Trientina/farmacologia , Zinco/metabolismo
18.
Br J Nutr ; 107(6): 893-902, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21899803

RESUMO

The present randomised trial investigated the effects of feeding Zambian infants from 6 to 18 months old either a richly or basal micronutrient-fortified complementary/replacement food on gut integrity and systemic inflammation. Blood samples were obtained from all infants (n 743) at 6 and 18 months for the assessment of serum C-reactive protein (CRP) and α1-acid glycoprotein (AGP). A subsample of 502 infants, selected from the main cohort to include a larger proportion of infants with HIV-positive mothers, was assigned to lactulose/mannitol gut permeability tests. Lactulose:mannitol (L:M) ratio analyses were adjusted for baseline urinary L:M ratio, socio-economic status, mother's education, season of birth and baseline stunting, and stratified by maternal antenatal HIV status, child's sex, concurrent breast-feeding status and anaemia at baseline. There was no significant difference in geometric mean L:M ratio between the richly fortified and basal-fortified porridge arms at 12 months (0·47 (95 % CI 0·41, 0·55) v. 0·41 (95 % CI 0·34, 0·49); P = 0·16 adjusted). At 18 months, the richly fortified porridge group had a significantly higher geometric mean L:M ratio than the basal-fortified group (0·23 (95 % CI 0·19, 0·28) v. 0·15 (95 % CI 0·12, 0·19); P = 0·02 adjusted). This effect was evident for all stratifications, significantly among boys (P = 0·04), among the infants of HIV-negative mothers (P = 0·01), among the infants of HIV-negative mothers not concurrently breast-fed (P = 0·01) and among those who were not anaemic at baseline (P = 0·03). CRP, but not AGP, was positively associated with L:M ratio, but there were no significant effects of the diet on either CRP or AGP. In conclusion, a richly fortified complementary/replacement food did not benefit and may have worsened intestinal permeability.


Assuntos
Proteína C-Reativa/análise , Alimentos Fortificados , Soropositividade para HIV/fisiopatologia , Alimentos Infantis , Absorção Intestinal , Síndromes de Malabsorção/dietoterapia , Micronutrientes/uso terapêutico , Anemia/complicações , Estudos de Coortes , Feminino , Alimentos Fortificados/análise , Soropositividade para HIV/congênito , Soropositividade para HIV/imunologia , Humanos , Lactente , Alimentos Infantis/análise , Intestinos/imunologia , Intestinos/fisiopatologia , Lactulose/metabolismo , Lactulose/urina , Perda de Seguimento , Síndromes de Malabsorção/complicações , Síndromes de Malabsorção/etiologia , Síndromes de Malabsorção/fisiopatologia , Masculino , Manitol/metabolismo , Manitol/urina , Permeabilidade , Caracteres Sexuais , Zâmbia
19.
Br J Nutr ; 107(4): 556-66, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21733297

RESUMO

It is uncertain whether multiple micronutrients benefit the mental and psychomotor development of young children in developing countries. We conducted a randomised double-blind controlled trial to evaluate the effect of a richly micronutrient-fortified v. a basal fortified porridge on mental and psychomotor development in Zambian infants. Infants (n 743) were randomised at age 6 months to receive either the richly fortified or the basal fortified infant food and were followed up until 18 months of age. All the infants were evaluated monthly for achievement of a series of developmental milestones. The Bayley scales of infant development II were administered to a subsample of 502 infants at 6, 12 and 18 months. Rich micronutrient fortification had no significant benefit on the following: (a) number of developmental milestones achieved (rate ratio at 12 months = 1·00; 95 % CI 0·96, 1·05; P = 0·81, adjusted for sex, socio-economic status and maternal education, with similar results at 15 and 18 months); (b) ages of walking unsupported (hazard ratio (HR) 1·04; 95 % CI 0·88, 1·24; P = 0·63, adjusted for the above covariates) and of speaking three or four clear words (HR 1·01; 95 % CI 0·84, 1·20; P = 0·94, adjusted for the above covariates); (c) mental development index (MDI) and psychomotor development index (PDI) of the Bayley scales (scores difference adjusted for baseline scores, age at the assessment, sex, socio-economic status, maternal education, language, age and HIV status: MDI 0·3 (95 % CI - 0·5, 1·1), P = 0·43; PDI - 0·1 (95 % CI - 0·9, 0·7), P = 0·78). In conclusion, the results do not support the hypothesis that rich micronutrient fortification improves Zambian infants' mental and motor development.


Assuntos
Desenvolvimento Infantil , Deficiências do Desenvolvimento/prevenção & controle , Alimentos Fortificados/análise , Alimentos Infantis/análise , Deficiência Intelectual/prevenção & controle , Micronutrientes/uso terapêutico , Transtornos das Habilidades Motoras/prevenção & controle , Países em Desenvolvimento , Deficiências do Desenvolvimento/epidemiologia , Método Duplo-Cego , Feminino , Humanos , Lactente , Deficiência Intelectual/epidemiologia , Transtornos do Desenvolvimento da Linguagem/epidemiologia , Transtornos do Desenvolvimento da Linguagem/prevenção & controle , Estudos Longitudinais , Masculino , Micronutrientes/administração & dosagem , Transtornos das Habilidades Motoras/epidemiologia , Pacientes Desistentes do Tratamento , Transtornos Psicomotores/epidemiologia , Transtornos Psicomotores/prevenção & controle , Caminhada , Zâmbia/epidemiologia
20.
Nanotechnology ; 23(49): 495104, 2012 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-23165288

RESUMO

A surprising and unexpected biomineralization process was observed during toxicological assessment of carbon nanoparticles on Paracentrotus lividus (sea urchin) pluteus larvae. The larvae activate a process of defense against external material, by incorporating the nanoparticles into microstructures of aragonite similarly to pearl oysters. Aiming at a better understanding of this phenomenon, the larvae were exposed to increasing concentrations of carbon nanoparticles and the biomineralization products were analyzed by electron microscopy, x-ray diffraction and Raman spectroscopy. In order to evaluate the possible influence of Sp-CyP-1 expression on this biomineralization process by larvae, analyses of gene expression (Sp-CyP-1) and calcein labeling were performed. Overall, we report experimental evidence about the capability of carbon nanoparticles to induce an increment of Sp-CyP-1 expression with the consequent activation of a biomineralization process leading to the production of a new pearl-like biomaterial never previously observed in sea urchins.


Assuntos
Minerais/metabolismo , Nanotubos de Carbono/toxicidade , Paracentrotus/efeitos dos fármacos , Paracentrotus/metabolismo , Animais , Relação Dose-Resposta a Droga , Larva/efeitos dos fármacos , Larva/metabolismo , Teste de Materiais , Minerais/análise
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