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1.
J Med Internet Res ; 24(3): e31684, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-35262495

RESUMO

For over a decade, Scotland has implemented and operationalized a system of Safe Havens, which provides secure analytics platforms for researchers to access linked, deidentified electronic health records (EHRs) while managing the risk of unauthorized reidentification. In this paper, a perspective is provided on the state-of-the-art Scottish Safe Haven network, including its evolution, to define the key activities required to scale the Scottish Safe Haven network's capability to facilitate research and health care improvement initiatives. A set of processes related to EHR data and their delivery in Scotland have been discussed. An interview with each Safe Haven was conducted to understand their services in detail, as well as their commonalities. The results show how Safe Havens in Scotland have protected privacy while facilitating the reuse of the EHR data. This study provides a common definition of a Safe Haven and promotes a consistent understanding among the Scottish Safe Haven network and the clinical and academic research community. We conclude by identifying areas where efficiencies across the network can be made to meet the needs of population-level studies at scale.


Assuntos
Registros Eletrônicos de Saúde , Privacidade , Humanos , Escócia
2.
Cochrane Database Syst Rev ; 5: CD011413, 2017 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-28539007

RESUMO

BACKGROUND: Direct laryngoscopy is the method currently used for tracheal intubation in children. It occasionally offers unexpectedly poor laryngeal views. Indirect laryngoscopy involves visualizing the vocal cords by means other than obtaining a direct sight, with the potential to improve outcomes. We reviewed the current available literature and performed a meta-analysis to compare direct versus indirect laryngoscopy, or videolaryngoscopy, with regards to efficacy and adverse effects. OBJECTIVES: To assess the efficacy of indirect laryngoscopy, or videolaryngoscopy, versus direct laryngoscopy for intubation of children with regards to intubation time, number of attempts at intubation, and adverse haemodynamic responses to endotracheal intubation. We also assessed other adverse responses to intubation, such as trauma to oral, pharyngeal, and laryngeal structures, and we assessed vocal cord view scores. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), and trial registers (www.clinicaltrials.gov and www.controlledtrials) in November 2015. We reran the search in January 2017. We added new studies of potential interest to a list of 'Studies awaiting classification' and will incorporate them into formal review findings during the review update. We performed reference checking and citation searching and contacted the authors of unpublished data to ask for more information. We applied no language restrictions. SELECTION CRITERIA: We included only randomized controlled trials. Participants were children aged 28 days to 18 years. Investigators performed intubations using any type of indirect laryngoscopes, or videolaryngoscopes, versus direct laryngoscopes. DATA COLLECTION AND ANALYSIS: We used Cochrane standard methodological procedures. Two review authors independently reviewed titles, extracted data, and assessed risk of bias. MAIN RESULTS: We included 12 studies (803 children) in this review and meta-analysis. We identified three studies that are awaiting classification and two ongoing studies.Trial results show that a longer intubation time was required when indirect laryngoscopy, or videolaryngoscopy, was used instead of direct laryngoscopy (12 trials; n = 798; mean difference (MD) 5.49 seconds, 95% confidence interval (CI) 1.37 to 9.60; I2 = 90%; very low-quality evidence). Researchers found no significant differences between direct and indirect laryngoscopy on assessment of success of the first attempt at intubation (11 trials; n = 749; risk ratio (RR) 0.96, 95% CI 0.91 to 1.02; I2 = 67%; low-quality evidence) and observed that unsuccessful intubation (five trials; n = 263) was significantly increased in the indirect laryngoscopy, or videolaryngoscopy, group (RR 4.93, 95% CI 1.33 to 18.31; I2 = 0%; low-quality evidence). Five studies reported the effect of intubation on oxygen saturation (n = 272; very low-quality evidence). Five children had desaturation during intubation: one from the direct laryngoscopy group and four from the indirect laryngoscopy, or videolaryngoscopy, group.Two studies (n = 100) reported other haemodynamic responses to intubation (very low-quality evidence). One study reported a significant increase in heart rate five minutes after intubation in the indirect laryngoscopy group (P = 0.007); the other study found that the heart rate change in the direct laryngoscopy group was significantly less than the heart rate change in the indirect laryngoscopy, or videolaryngoscopy, group (P < 0.001). A total of five studies (n = 244; very low-quality evidence) looked at evidence of trauma resulting from intubation. Investigators reported that only two children from the direct laryngoscopy group had trauma compared with no children in the indirect laryngoscopy, or videolaryngoscopy, group.Use of indirect laryngoscopy, or videolaryngoscopy, improved the percentage of glottic opening (five trials; n = 256). Studies noted no significant difference in Cormack and Lehane score (C&L) grade 1 (three trials; n = 190; RR 1.06, 95% CI 0.93 to 1.21; I2 = 59%). AUTHORS' CONCLUSIONS: Evidence suggests that indirect laryngoscopy, or videolaryngoscopy, leads to prolonged intubation time with an increased rate of intubation failure when compared with direct laryngoscopy (very low-quality evidence due to imprecision, inconsistency, and study limitations). Review authors had difficulty reaching conclusions on adverse haemodynamic responses and other adverse effects of intubation, as only a few children were reported to have these outcomes. Use of indirect laryngoscopy, or videolaryngoscopy, might lead to improved vocal cord view, but marked heterogeneity between studies made it difficult for review authors to reach conclusions on this outcome.


Assuntos
Intubação Intratraqueal/métodos , Laringoscopia/métodos , Adolescente , Criança , Pré-Escolar , Frequência Cardíaca , Humanos , Lactente , Intubação Intratraqueal/efeitos adversos , Intubação Intratraqueal/estatística & dados numéricos , Laringoscopia/efeitos adversos , Laringoscopia/estatística & dados numéricos , Oxigênio/sangue , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Tempo , Prega Vocal/diagnóstico por imagem
3.
Malar J ; 15(1): 377, 2016 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-27448805

RESUMO

BACKGROUND: In this phase 1 clinical trial, healthy adult, malaria-naïve subjects were immunized with radiation-attenuated Plasmodium falciparum sporozoites (PfRAS) by mosquito bite and then underwent controlled human malaria infection (CHMI). The PfRAS model for immunization against malaria had previously induced >90 % sterile protection against homologous CHMI. This study was to further explore the safety, tolerability and protective efficacy of the PfRAS model and to provide biological specimens to characterize protective immune responses and identify protective antigens in support of malaria vaccine development. METHODS: Fifty-seven subjects were screened, 41 enrolled and 30 received at least one immunization. The true-immunized subjects received PfRAS via mosquito bite and the mock-immunized subjects received mosquito bites from irradiated uninfected mosquitoes. Sera and peripheral blood mononuclear cells (PBMCs) were collected before and after PfRAS immunizations. RESULTS: Immunization with PfRAS was generally safe and well tolerated, and repeated immunization via mosquito bite did not appear to increase the risk or severity of AEs. Local adverse events (AEs) of true-immunized and mock-immunized groups consisted of erythaema, papules, swelling, and induration and were consistent with reactions from mosquito bites seen in nature. Two subjects, one true- and one mock-immunized, developed large local reactions that completely resolved, were likely a result of mosquito salivary antigens, and were withdrawn from further participation as a safety precaution. Systemic AEs were generally rare and mild, consisting of headache, myalgia, nausea, and low-grade fevers. Two true-immunized subjects experienced fever, malaise, myalgia, nausea, and rigours approximately 16 h after immunization. These symptoms likely resulted from pre-formed antibodies interacting with mosquito salivary antigens. Ten subjects immunized with PfRAS underwent CHMI and five subjects (50 %) were sterilely protected and there was a significant delay to parasitaemia in the other five subjects. All ten subjects developed humoral immune responses to whole sporozoites and to the circumsporozoite protein prior to CHMI, although the differences between protected and non-protected subjects were not statistically significant for this small sample size. CONCLUSIONS: The protective efficacy of this clinical trial (50 %) was notably less than previously reported (>90 %). This may be related to differences in host genetics or the inherent variability in mosquito biting behavior and numbers of sporozoites injected. Differences in trial procedures, such as the use of leukapheresis prior to CHMI and of a longer interval between the final immunization and CHMI in these subjects compared to earlier trials, may also have reduced protective efficacy. This trial has been retrospectively registered at ISRCTN ID 17372582, May 31, 2016.


Assuntos
Anticorpos Antiprotozoários/sangue , Culicidae/fisiologia , Mordeduras e Picadas de Insetos , Vacinas Antimaláricas/efeitos adversos , Vacinas Antimaláricas/imunologia , Malária Falciparum/prevenção & controle , Plasmodium falciparum/imunologia , Adolescente , Adulto , Animais , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Humanos , Vacinas Antimaláricas/administração & dosagem , Masculino , Pessoa de Meia-Idade , Plasmodium falciparum/efeitos da radiação , Esporozoítos/imunologia , Esporozoítos/efeitos da radiação , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/efeitos adversos , Vacinas Atenuadas/imunologia , Adulto Jovem
4.
J Infect Dis ; 205(9): 1456-63, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22457289

RESUMO

Malaria continues to be a major public health concern, and there are concerted efforts to eliminate it. The quest for a vaccine remains a top priority, and vaccines based on the circumsporozoite protein (CSP) are among the lead candidates, with the RTS,S vaccine currently undergoing phase 3 testing in Africa. Previous studies have reported anti-CSP antibody-mediated enhancement of in vitro invasion of homologous sporozoites. This effect has been shown to be concentration dependent; high-level antibodies are inhibitory, whereas low-level antibodies lead to enhancement of invasion. Nondominant shared epitopes may lead to the generation of low titers of cross-reactive antibodies that may prove to be detrimental. We report cross-species recognition of Plasmodium falciparum and Plasmodium berghei sporozoites by anti-Plasmodium vivax CSP serum samples. In addition, we report that vaccination of mice with VMP001, a P. vivax CSP vaccine candidate, reduces, not enhances, P. berghei infection in mice.


Assuntos
Proteção Cruzada , Vacinas Antimaláricas/imunologia , Malária/imunologia , Malária/prevenção & controle , Proteínas de Protozoários/imunologia , África , Sequência de Aminoácidos , Animais , Anticorpos Antiprotozoários/sangue , Epitopos/imunologia , Feminino , Imunização , Vacinas Antimaláricas/genética , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Plasmodium berghei/imunologia , Plasmodium falciparum/imunologia , Plasmodium vivax/imunologia , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Análise de Sequência de DNA , Especificidade da Espécie , Esporozoítos/imunologia
5.
Ther Adv Rare Dis ; 4: 26330040231219272, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38152157

RESUMO

Background: The current road to developing treatments for rare diseases is often slow, expensive, and riddled with risk. Change is needed to improve the process, both in how we think about rare disease treatment development and the infrastructure we build to support ongoing science. The National Institutes of Health (NIH)-supported Rare Diseases Clinical Research Network (RDCRN) was established to advance the diagnosis, management, and treatment of rare diseases and to promote highly collaborative, multi-site, patient-centric, translational, and clinical research. The current iteration of the RDCRN intends to build upon and enhance successful approaches within the network while identifying innovative methods to fill gaps and address needs in the approach to the rare disease treatment development process through innovation, collaboration, and clinical trial readiness. Objective: The objective of this paper is to provide an overview of the productivity and influence of the RDCRN since it was first established 20 years ago. Design and methods: Using a suite of tools available to NIH staff that provides access to a comprehensive, curated, extensively linked data set of global grants, patents, publications, clinical trials, and FDA-approved drugs, a series of queries were executed that conducted bibliometric, co-author, and co-occurrence analysis. Results: The results demonstrate that the entire RDCRN consortia and network has been highly productive since its inception. They have produced 2763 high-quality publications that have been cited more than 100,000 times, expanded international networks, and contributed scientifically to eight FDA-approved treatments for rare diseases. Conclusion: The RDCRN program has successfully addressed some significant challenges while developing treatments for rare diseases. However, looking to the future and being agile in facing new challenges that arise as science progresses is important.


A National Institute of Health-funded research network working toward better treatments for people with rare diseases The Rare Diseases Clinical Research Network (RDCRN) is a Federally directed research network that targets research to help investigators move closer to treatments for rare diseases. The network supports 20 different groups that study rare diseases. Each group focuses on three or more rare diseases and the research is conducted at multiple sites. Each group works closely with both the National Institutes of Health (NIH) and patient advocacy groups. The primary focus of the network is clinical trials readiness, which simply means knowing who to treat, when to treat, and how to treat, thus taking some of the risk out of clinical trials. This knowledge is gained through natural history studies. The network, supported by grants, holds a competition every five years to select groups to participate in the network. The RDCRN is supported by ten different institutes at the NIH. To date the RDCRN has published numerous manuscripts in topics ranging from findings from natural history studies and case reports to practice guidelines and clinical trials. To date the RDCRN has been involved in work that has led to eight treatments being approved by the Food and Drug Administration (FDA).

6.
Infect Immun ; 79(9): 3492-500, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21690242

RESUMO

Plasmodium vivax is the major cause of malaria outside sub-Saharan Africa and inflicts debilitating morbidity and consequent economic impacts in developing countries. In order to produce a P. vivax vaccine for global use, we have previously reported the development of a novel chimeric recombinant protein, VMP001, based on the circumsporozoite protein (CSP) of P. vivax. Very few adjuvant formulations are currently available for human use. Our interest is to evaluate second-generation vaccine formulations to identify novel combinations of adjuvants capable of inducing strong, long-lasting immune responses. In this study rhesus monkeys were immunized intramuscularly three times with VMP001 in combination with a stable emulsion (SE) or a synthetic Toll-like receptor 4 (TLR4) agonist (glucopyranosyl lipid A [GLA]) in SE (GLA-SE). Sera and peripheral blood mononuclear cells (PBMCs) were tested for the presence of antigen-specific humoral and cellular responses, respectively. All groups of monkeys generated high titers of anti-P. vivax IgG antibodies, as detected by enzyme-linked immunosorbent assays (ELISAs) and immunofluorescence assays. In addition, all groups generated a cellular immune response characterized by antigen-specific CD4(+) T cells secreting predominantly interleukin-2 (IL-2) and lesser amounts of tumor necrosis factor (TNF). We conclude that the combination of VMP001 and GLA-SE is safe and immunogenic in monkeys and may serve as a potential second-generation vaccine candidate against P. vivax malaria.


Assuntos
Vacinas Antimaláricas/imunologia , Malária Vivax/prevenção & controle , Plasmodium vivax/imunologia , Receptor 4 Toll-Like/agonistas , Adjuvantes Imunológicos , Animais , Antígenos de Protozoários/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos , Emulsões , Ensaio de Imunoadsorção Enzimática , Imunofluorescência , Imunoglobulina G/sangue , Interferon gama/biossíntese , Interleucina-2/biossíntese , Interleucina-2/metabolismo , Lipídeo A/imunologia , Macaca mulatta , Malária Vivax/imunologia , Proteínas de Protozoários/imunologia , Receptor 4 Toll-Like/imunologia , Fator de Necrose Tumoral alfa/biossíntese , Vacinas Sintéticas/imunologia
7.
Exp Brain Res ; 211(3-4): 495-503, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21448575

RESUMO

The temporal coordination of interpersonal behavior is a foundation for effective joint action with synchronized movement moderating core components of person perception and social exchange. Questions remain, however, regarding the precise conditions under which interpersonal synchrony emerges. In particular, with whom do people reliably synchronize their movements? The current investigation explored the effects of arbitrary group membership (i.e., minimal groups) on the emergence of interpersonal coordination. Participants performed a repetitive rhythmic action together with a member of the same or a different minimal group. Of interest was the extent to which participants spontaneously synchronized their movements with those of the target. Results revealed that stable coordination (i.e., in-phase synchrony) was most pronounced when participants interacted with a member of a different minimal group. These findings are discussed with respect to the functional role of interpersonal synchrony and the potential avenues by which the dynamics of rhythmic coordination may be influenced by group status.


Assuntos
Relações Interpessoais , Movimento , Desempenho Psicomotor , Identificação Social , Feminino , Humanos , Percepção Visual , Adulto Jovem
8.
PLoS One ; 16(8): e0256396, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34415964

RESUMO

BACKGROUND: Immunization with radiation-attenuated sporozoites (RAS) by mosquito bites provides >90% sterile protection against Plasmodium falciparum malaria in humans. We conducted a clinical trial based on data from previous RAS clinical trials that suggested that 800-1200 infected bites should induce ~50% protective vaccine efficacy (VE) against controlled human malaria infection (CHMI) administered three weeks after the final immunization. Two cohorts were immunized separately. VE was 55% in Cohort 1 but 90% in Cohort 2, the cohort that received a higher first dose and a reduced (fractional) fifth dose. Immune responses were better boosted by the fractional fifth dose in Cohort 2 and suggested the importance of the fractional fifth dose for increased protection in Cohort 2 responses. Three protected subjects were later boosted and were protected suggesting that protection could be extended to at least 67 weeks. METHODS: The ex vivo FluoroSpot assay was used to measure peripheral IFN-γ, IL2, and IFN-γ+IL2 responses to PfNF54 sporozoites and malaria antigens CSP, AMA1, TRAP, and CelTOS using pools of synthetic overlapping 15mer peptides spanning each antigen. RESULTS: There was no correlation between IFN-γ, IL2, and IFN-γ+IL2 responses to sporozoites and protection, but fold-increases between post-4th and post-5th responses greater than 1.0 occurred mostly in protected subjects. IFN-γ and IL2 responses to TRAP, CelTOS and CSP occurred only in protected subjects. Peripheral IFN-γ, IL2, and IFN-γ+IL2 responses were short-lived and low by 27 weeks post-CHMI but were restored by boosting. CONCLUSIONS: These studies highlight the importance of vaccine dose and schedule for vaccine efficacy, and suggest that CSP, TRAP, AMA1 and CelTOS may be targets of protective immunity. The correlation between fold-increases in responses and protection should be explored in other vaccine trials. TRIAL REGISTRATION: ClinicalTrials.gov NCT01994525.


Assuntos
Plasmodium falciparum , Esporozoítos , Mordeduras e Picadas de Insetos , Eficácia de Vacinas
9.
J Exp Med ; 200(9): 1111-21, 2004 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-15504820

RESUMO

Immunoglobulin class switch recombination (Ig CSR) involves DNA double strand breaks (DSBs) at recombining switch regions and repair of these breaks by nonhomologous end-joining. Because the protein kinase ataxia telengiectasia (AT) mutated (ATM) plays a critical role in DSB repair and AT patients show abnormalities of Ig isotype expression, we assessed the role of ATM in CSR by examining ATM-deficient mice. In response to T cell-dependent antigen (Ag), Atm-/- mice secreted substantially less Ag-specific IgA, IgG1, IgG2b, and IgG3, and less total IgE than Atm+/+ controls. To determine whether Atm-/- B cells have an intrinsic defect in their ability to undergo CSR, we analyzed in vitro responses of purified B cells. Atm-/- cells secreted substantially less IgA, IgG1, IgG2a, IgG3, and IgE than wild-type (WT) controls in response to stimulation with lipopolysaccharide, CD40 ligand, or anti-IgD plus appropriate cytokines. Molecular analysis of in vitro responses indicated that WT and Atm-/- B cells produced equivalent amounts of germline IgG1 and IgE transcripts, whereas Atm-/- B cells produced markedly reduced productive IgG1 and IgE transcripts. The reduction in isotype switching by Atm-/- B cells occurs at the level of genomic DNA recombination as measured by digestion-circularization PCR. Analysis of sequences at CSR sites indicated that there is greater microhomology at the mu-gamma1 switch junctions in ATM B cells than in wild-type B cells, suggesting that ATM function affects the need or preference for sequence homology in the CSR process. These findings suggest a role of ATM in DNA DSB recognition and/or repair during CSR.


Assuntos
Linfócitos B/imunologia , Reparo do DNA , Switching de Imunoglobulina/genética , Proteínas Serina-Treonina Quinases/genética , Recombinação Genética/genética , Animais , Proteínas Mutadas de Ataxia Telangiectasia , Sequência de Bases , Proteínas de Ciclo Celular , Primers do DNA , Proteínas de Ligação a DNA , Ensaio de Imunoadsorção Enzimática , Fluoresceínas , Haptenos , Hemocianinas , Switching de Imunoglobulina/imunologia , Região de Troca de Imunoglobulinas/genética , Imunoglobulinas/genética , Imunoglobulinas/metabolismo , Camundongos , Camundongos Mutantes , Reação em Cadeia da Polimerase/métodos , Recombinação Genética/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Homologia de Sequência , Hipermutação Somática de Imunoglobulina/genética , Succinimidas , Proteínas Supressoras de Tumor
10.
J Exp Med ; 195(7): 811-23, 2002 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11927626

RESUMO

The c-Jun NH(2)-terminal kinase (JNK) signaling pathway is induced by cytokines and stress stimuli and is implicated in cell death and differentiation, but the specific function of this pathway depends on the cell type. Here we examined the role of JNK1 and JNK2 in CD8(+) T cells. Unlike CD4(+) T cells, the absence of JNK2 causes increased interleukin (IL)-2 production and proliferation of CD8(+) T cells. In contrast, JNK1-deficient CD8(+) T cells are unable to undergo antigen-stimulated expansion in vitro, even in the presence of exogenous IL-2. The hypoproliferation of these cells is associated with impaired IL-2 receptor alpha chain (CD25) gene and cell surface expression. The reduced level of nuclear activating protein 1 (AP-1) complexes in activated JNK1-deficient CD8(+) T cells can account for the impaired IL-2 receptor alpha chain gene expression. Thus, JNK1 and JNK2 play different roles during CD8(+) T cell activation and these roles differ from those in CD4(+) T cells.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Ativação Linfocitária/imunologia , Proteínas Quinases Ativadas por Mitógeno/imunologia , Animais , Vírus da Influenza A/imunologia , Interleucina-2/farmacologia , Subunidade alfa de Receptor de Interleucina-2 , Linfonodos/imunologia , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Knockout , Proteína Quinase 8 Ativada por Mitógeno , Proteína Quinase 9 Ativada por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/deficiência , Proteínas Quinases Ativadas por Mitógeno/genética , Infecções por Orthomyxoviridae/imunologia , Receptores de Interleucina/imunologia , Baço/imunologia , Fatores de Tempo
11.
J Immunol ; 181(2): 907-17, 2008 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-18606642

RESUMO

Invariant NKT (iNKT) cells are a population of TCRalphabeta-expressing cells that are unique in several respects. In contrast to conventional T cells, iNKT cells are selected in the thymus for recognition of CD1, rather than conventional MHC class I or II, and are selected by CD1-expressing double-positive thymocytes, rather than by the thymic stromal cells responsible for positive selection of conventional T cells. We have probed further the requirements for thymic iNKT cell development and find that these cells are highly sensitive to B7-CD28 costimulatory interactions, as evidenced by the substantially decreased numbers of thymic iNKT cells in CD28 and in B7 knockout mice. In contrast to the requirement for CD1, B7-CD28 signaling does not affect early iNKT cell lineage commitment, but exerts its influence on the subsequent intrathymic expansion and differentiation of iNKT cells. CD28 wild-type/CD28-deficient mixed bone marrow chimeras provided evidence of both cell-autonomous and non-cell-autonomous roles for CD28 during iNKT cell development. Paradoxically, transgenic mice in which thymic expression of B7 is elevated have essentially no measurable thymic iNKT cells. Taken together, these results demonstrate that the unique pathway involved in iNKT cell development is marked by a critical role of B7-CD28 interactions and that disruption or augmentation of this costimulatory interaction has substantial effects on iNKT cell development in the thymus.


Assuntos
Antígenos CD1/metabolismo , Antígeno B7-1/metabolismo , Antígenos CD28/metabolismo , Células Matadoras Naturais/imunologia , Animais , Antígenos CD1/imunologia , Antígeno B7-1/imunologia , Antígenos CD28/imunologia , Diferenciação Celular , Células Matadoras Naturais/citologia , Células Matadoras Naturais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Timo/imunologia , Timo/metabolismo
12.
PLoS One ; 15(5): e0232234, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32407410

RESUMO

Only a small fraction of the antigens expressed by malaria parasites have been evaluated as vaccine candidates. A successful malaria subunit vaccine will likely require multiple antigenic targets to achieve broad protection with high protective efficacy. Here we describe protective efficacy of a novel antigen, Plasmodium yoelii (Py) E140 (PyE140), evaluated against P. yoelii challenge of mice. Vaccines targeting PyE140 reproducibly induced up to 100% sterile protection in both inbred and outbred murine challenge models. Although PyE140 immunization induced high frequency and multifunctional CD8+ T cell responses, as well as CD4+ T cell responses, protection was mediated by PyE140 antibodies acting against blood stage parasites. Protection in mice was long-lasting with up to 100% sterile protection at twelve weeks post-immunization and durable high titer anti-PyE140 antibodies. The E140 antigen is expressed in all Plasmodium species, is highly conserved in both P. falciparum lab-adapted strains and endemic circulating parasites, and is thus a promising lead vaccine candidate for future evaluation against human malaria parasite species.


Assuntos
Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/imunologia , Imunização , Malária/prevenção & controle , Plasmodium yoelii/fisiologia , Animais , Antígenos de Protozoários/genética , Reações Cruzadas , Feminino , Regulação da Expressão Gênica , Camundongos , Plasmodium yoelii/genética , Plasmodium yoelii/imunologia
13.
PLoS One ; 15(6): e0233840, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32555601

RESUMO

BACKGROUND: Immunization with radiation-attenuated sporozoites (RAS) by mosquito bite provides >90% sterile protection against Plasmodium falciparum (Pf) malaria in humans. RAS invade hepatocytes but do not replicate. CD8+ T cells recognizing parasite-derived peptides on the surface of infected hepatocytes are likely the primary protective mechanism. We conducted a randomized clinical trial of RAS immunization to assess safety, to achieve 50% vaccine efficacy (VE) against controlled human malaria infection (CHMI), and to generate reagents from protected and non-protected subjects for future identification of protective immune mechanisms and antigens. METHODS: Two cohorts (Cohort 1 and Cohort 2) of healthy, malaria-naïve, non-pregnant adults age 18-50 received five monthly immunizations with infected (true-immunized, n = 21) or non-infected (mock-immunized, n = 5) mosquito bites and underwent homologous CHMI at 3 weeks. Immunization parameters were selected for 50% protection based on prior clinical data. Leukapheresis was done to collect plasma and peripheral blood mononuclear cells. RESULTS: Adverse event rates were similar in true- and mock-immunized subjects. Two true- and two mock-immunized subjects developed large local reactions likely caused by mosquito salivary gland antigens. In Cohort 1, 11 subjects received 810-1235 infected bites; 6/11 (55%) were protected against CHMI vs. 0/3 mock-immunized and 0/6 infectivity controls (VE 55%). In Cohort 2, 10 subjects received 839-1131 infected bites with a higher first dose and a reduced fifth dose; 9/10 (90%) were protected vs. 0/2 mock-immunized and 0/6 controls (VE 90%). Three/3 (100%) protected subjects administered three booster immunizations were protected against repeat CHMI vs. 0/6 controls (VE 100%). Cohort 2 uniquely showed a significant rise in IFN-γ responses after the third and fifth immunizations and higher antibody responses to CSP. CONCLUSIONS: PfRAS were generally safe and well tolerated. Cohort 2 had a higher first dose, reduced final dose, higher antibody responses to CSP and significant rise of IFN-γ responses after the third and fifth immunizations. Whether any of these factors contributed to increased protection in Cohort 2 requires further investigation. A cryobank of sera and cells from protected and non-protected individuals was generated for future immunological studies and antigen discovery. TRIAL REGISTRATION: ClinicalTrials.gov NCT01994525.


Assuntos
Mordeduras e Picadas de Insetos/imunologia , Malária/prevenção & controle , Esporozoítos/imunologia , Vacinação/métodos , Vacinas Atenuadas/efeitos adversos , Adulto , Animais , Anopheles/parasitologia , Anopheles/fisiologia , Feminino , Raios gama , Humanos , Malária/imunologia , Masculino , Pessoa de Meia-Idade , Mosquitos Vetores/parasitologia , Mosquitos Vetores/fisiologia , Plasmodium falciparum/crescimento & desenvolvimento , Plasmodium falciparum/imunologia , Plasmodium falciparum/patogenicidade , Proteínas de Protozoários/imunologia , Esporozoítos/patogenicidade , Esporozoítos/efeitos da radiação , Vacinação/efeitos adversos
14.
PLoS Negl Trop Dis ; 10(2): e0004423, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26919472

RESUMO

BACKGROUND: A vaccine to prevent infection and disease caused by Plasmodium vivax is needed both to reduce the morbidity caused by this parasite and as a key component in efforts to eradicate malaria worldwide. Vivax malaria protein 1 (VMP001), a novel chimeric protein that incorporates the amino- and carboxy- terminal regions of the circumsporozoite protein (CSP) and a truncated repeat region that contains repeat sequences from both the VK210 (type 1) and the VK247 (type 2) parasites, was developed as a vaccine candidate for global use. METHODS: We conducted a first-in-human Phase 1 dose escalation vaccine study with controlled human malaria infection (CHMI) of VMP001 formulated in the GSK Adjuvant System AS01B. A total of 30 volunteers divided into 3 groups (10 per group) were given 3 intramuscular injections of 15 µg, 30 µg, or 60 µg respectively of VMP001, all formulated in 500 µL of AS01B at each immunization. All vaccinated volunteers participated in a P. vivax CHMI 14 days following the third immunization. Six non-vaccinated subjects served as infectivity controls. RESULTS: The vaccine was shown to be well tolerated and immunogenic. All volunteers generated robust humoral and cellular immune responses to the vaccine antigen. Vaccination did not induce sterile protection; however, a small but significant delay in time to parasitemia was seen in 59% of vaccinated subjects compared to the control group. An association was identified between levels of anti-type 1 repeat antibodies and prepatent period. SIGNIFICANCE: This trial was the first to assess the efficacy of a P. vivax CSP vaccine candidate by CHMI. The association of type 1 repeat-specific antibody responses with delay in the prepatency period suggests that augmenting the immune responses to this domain may improve strain-specific vaccine efficacy. The availability of a P. vivax CHMI model will accelerate the process of P. vivax vaccine development, allowing better selection of candidate vaccines for advancement to field trials.


Assuntos
Vacinas Antimaláricas/imunologia , Malária Vivax/prevenção & controle , Plasmodium vivax/imunologia , Proteínas de Protozoários/imunologia , Adolescente , Adulto , Anticorpos Antiprotozoários/imunologia , Feminino , Humanos , Vacinas Antimaláricas/administração & dosagem , Vacinas Antimaláricas/efeitos adversos , Malária Vivax/imunologia , Malária Vivax/parasitologia , Masculino , Pessoa de Meia-Idade , Proteínas de Protozoários/administração & dosagem , Proteínas de Protozoários/efeitos adversos , Vacinação , Adulto Jovem
15.
Vaccine ; 33(52): 7551-8, 2015 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-26458800

RESUMO

Malaria remains an important health threat to non-immune travelers with the explosive growth of global travel. Populations at high risk of acquiring malaria infections include once semi-immune travelers who visit friends and relatives, military forces, business travelers and international tourists with destinations to sub-Saharan Africa, where malaria transmission intensity is high. Most malaria cases have been associated with poor compliance with existing preventive measures, including chemoprophylaxis. High risk groups would benefit immensely from an efficacious vaccine to protect them against malaria infection and together make up a sizable market for such a vaccine. The attributes of an ideal malaria vaccine for non-immune travelers and military personnel include a protective efficacy of 80% or greater, durability for at least 6 months, an acceptable safety profile and compatibility with existing preventive measures. It is very likely that a malaria vaccine designed to effectively prevent infection and clinical disease in the non-immune traveler and military personnel will also protect semi-immune residents of malaria-endemic areas and contribute to malaria elimination by reducing or blocking malaria transmission. The RTS,S vaccine (GlaxoSmithKline) and the PfSPZ Vaccine (Sanaria Inc) are the leading products that would make excellent vaccine candidates for these vulnerable populations.


Assuntos
Vacinas Antimaláricas , Malária/prevenção & controle , Militares , Viagem , África Subsaariana/epidemiologia , Antimaláricos/uso terapêutico , Ensaios Clínicos como Assunto , Humanos , Malária/epidemiologia , Malária/transmissão , Vacinas Antimaláricas/imunologia , Profilaxia Pré-Exposição , Vacinas Sintéticas/imunologia
16.
Front Psychol ; 5: 1064, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25285090

RESUMO

Synchronized behavior has significant social influence both in terms of everyday activities (e.g., walking and talking) as well as via more historical contexts (e.g., cultural rituals). Grounded in the science of coordination dynamics, previous research has revealed that interpersonal synchrony has numerous affiliative and pro-social consequences, such as enhanced rapport, cooperation, and social-cognitive functioning. The current study sought to explore the impact of intentional synchrony versus asynchrony on an individual's self-esteem and their feelings of social connection with a partner. The results revealed that individuals felt better about themselves following a period of synchronous compared to asynchronous movement, while they also perceived a greater self-other overlap with their partner. These findings not only extend previous research on social connections following interpersonal synchrony, but also provide the first demonstration of an influence on self-evaluations. Overall, it appears that moving in time with others may result in us feeling better about ourselves compared to moving to our own rhythm.

17.
Perception ; 41(12): 1529-31, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23586290

RESUMO

The spectacle of synchronous activity is both engaging and, for the social perceiver, informative. Judgments of the quality of social interactions covary with key characteristics of coordination dynamics (ie relative phase). Here we examined the converse relationship--are perceptions of synchrony shaped by social factors? Participants judged dyads consisting of individuals with dissimilar skin tones to be less coordinated than those with similar complexions, despite the amount of coordination being objectively equivalent. The methodological and practical implications of these findings are discussed.


Assuntos
Face , Percepção Social , Percepção do Tempo/fisiologia , Adulto , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Pele
18.
Vaccine ; 30(22): 3311-9, 2012 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-22425788

RESUMO

Plasmodium vivax is the major cause of malaria outside of sub-Saharan Africa and causes morbidity and results in significant economic impact in developing countries. In order to produce a P. vivax vaccine for global use, we have previously reported the development of VMP001, based on the circumsporozoite protein (CSP) of P. vivax. Our interest is to evaluate second-generation vaccine formulations to identify novel combinations of adjuvants capable of inducing strong, long-lasting immune responses. In this study, groups of C57BL/6J mice were immunized subcutaneously three times with VMP001 emulsified with synthetic TLR4 (GLA) or TLR7/8 (R848) agonist in stable emulsion (SE), a combination of the TLR4 and TLR7/8 agonists, or SE alone. Sera and splenocytes were tested for the presence of antigen-specific humoral and cellular responses, respectively. All groups of mice generated high titers of anti-P. vivax IgG antibodies as detected by ELISA and immunofluorescence assay. GLA-SE promoted a shift in the antibody response to a Th1 profile, as demonstrated by the change in IgG2c/IgG1 ratio. In addition, GLA-SE induced a strong cellular immune response characterized by multi-functional, antigen-specific CD4(+) T cells secreting IL-2, TNF and IFN-γ. In contrast, mice immunized with SE or R848-SE produced low numbers of antigen-specific CD4(+) T cells, and these T cells secreted IL-2 and TNF, but not IFN-γ. Finally, R848-SE did not enhance the immune response compared to GLA-SE alone. Based on these results, we conclude that the combination of VMP001 and GLA-SE is highly immunogenic in mice and may serve as a potential second-generation vaccine candidate against vivax malaria.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Vacinas Antimaláricas/imunologia , Plasmodium vivax/imunologia , Proteínas de Protozoários/imunologia , Animais , Anticorpos Antiprotozoários/sangue , Linfócitos T CD4-Positivos/imunologia , Emulsões/administração & dosagem , Ensaio de Imunoadsorção Enzimática , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Imunoglobulina G/sangue , Injeções Subcutâneas , Interferon gama/metabolismo , Interleucina-2/metabolismo , Vacinas Antimaláricas/administração & dosagem , Camundongos , Camundongos Endogâmicos C57BL , Proteínas de Protozoários/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologia
19.
Psychon Bull Rev ; 18(3): 598-604, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21347879

RESUMO

Spatial representations of time are a ubiquitous feature of human cognition. Nevertheless, interesting sociolinguistic variations exist with respect to where in space people locate temporal constructs. For instance, while in English time metaphorically flows horizontally, in Mandarin an additional vertical dimension is employed. Noting that the bilingual mind can flexibly accommodate multiple representations, the present work explored whether Mandarin-English bilinguals possess two mental time lines. Across two experiments, we demonstrated that Mandarin-English bilinguals do indeed employ both horizontal and vertical representations of time. Importantly, subtle variations to cultural context were seen to shape how these time lines were deployed.


Assuntos
Multilinguismo , Psicolinguística , Percepção Espacial , Percepção do Tempo , China , Inglaterra , Feminino , Humanos , Masculino , Processos Mentais , Adulto Jovem
20.
Vaccine ; 29(48): 8847-54, 2011 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-21983360

RESUMO

In a Phase 2a trial of the RTS,S/AS vaccine, we described significant association between protection against infection and vaccine-induced CD4 T cells. To determine whether processing of the circumsporozoite protein as a component of the RTS,S particulate antigen yields the same HLA-DR-restricted epitopes as those recognized by CD4 T cells from donors immunized by exposure to attenuated or infectious sporozoites we mapped the specificities of the RTS,S primed CD4 T cells by measuring IFN-γ cultured Elispot responses to pairs of overlapping 15 a.a. peptides that span the protein's C-terminus. Peptide pairs representing the previously described TH2R, T* and CS.T3 epitopes, were immunoprevalent and immunodominant. There was no response to the peptides corresponding to the human thrombospondin homology region. Responses to the CD4 T cell epitopes were restricted by multiple HLA-DR haplotypes. Of note, HLA-DR4 and HLA-DR11 restricted epitopes in the T* region and in the location on the CS protein defined by peptide pair 4, respectively. We conclude that processing of the CS protein derived from the RTS,S antigen leads to the generation of HLA-DR-restricted epitopes that are similar to those identified previously using CD4 T cells from subjects immunized with and protected by attenuated sporozoites or exposed to infectious sporozoites. This may in part account for the protective efficacy of the RTS,S/AS vaccine.


Assuntos
Apresentação de Antígeno , Linfócitos T CD4-Positivos/imunologia , Vacinas Antimaláricas/imunologia , Proteínas de Protozoários/imunologia , Especificidade do Receptor de Antígeno de Linfócitos T , Sequência de Aminoácidos , Antígenos de Protozoários/imunologia , Células Cultivadas , Epitopos de Linfócito T/imunologia , Subtipos Sorológicos de HLA-DR/imunologia , Antígeno HLA-DR4/imunologia , Humanos , Imunização Secundária , Interferon gama/imunologia , Leucócitos Mononucleares/imunologia , Vacinas Antimaláricas/administração & dosagem , Dados de Sequência Molecular , Plasmodium falciparum/imunologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Trombospondina 1/imunologia
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