RESUMO
Virus-like particles (VLPs) can be rapidly developed from influenza virus genetic sequences in order to supply vaccine after the onset of a pandemic. The safety and immunogenicity of one or two doses of a recombinant A (H1N1) 2009 influenza VLP vaccine was evaluated in a two-stage, Phase 2, randomized, double-blind, placebo-controlled study conducted in 4563 healthy adults, 18-64 years of age, during the H1N1 2009 pandemic in Mexico. In Part A, 1013 subjects were randomized into four treatment groups (5 µg, 15 µg, or 45 µg hemagglutinin [HA] VLP vaccine or placebo) and vaccinated 21 days apart, with sera collected on Days 1, 14 and 36 for hemagglutination inhibition (HAI) testing. After review of safety and immunogenicity data from Part A, additional subjects were immunized with a single dose of 15 µg VLP vaccine (N=2537) or placebo (N=1011) and assessed for safety in Part B. Results showed the H1N1 2009 VLP vaccine was safe and well-tolerated. Systemic solicited events were similar between placebo and VLP vaccinated groups with no vaccine-related serious adverse events. Dose response trends for solicited local adverse events were observed, with higher incidences of local pain, swelling, tenderness, and redness reported in the higher VLP dose groups (15 µg and 45 µg) compared to the placebo and 5 µg VLP groups following both vaccinations. Although the majority of local AEs were mild in severity, a dose trend in events of moderate or greater severity was also noted for these solicited events. The VLP vaccine groups demonstrated robust HAI immune responses after a single vaccination, with high rates of seroprotection (≥ 40 HAI titer) in 82-92% of all subjects and in 64-85% of subjects who were seronegative at the time of immunization. HAI geometric mean titers (GMTs), geometric mean ratios (GMRs) and seroconversion rates were also all statistically higher in the VLP groups compared to placebo for both post-baseline time points. Based on these data, additional clinical trials are in development to evaluate influenza vaccine candidate antigens manufactured using Spodoptera frugiperda (Sf9)/baculovirus-based VLP technology.
Assuntos
Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/efeitos adversos , Vacinas contra Influenza/imunologia , Vacinação/métodos , Adolescente , Adulto , Idoso , Animais , Anticorpos Antivirais/sangue , Baculoviridae/genética , Linhagem Celular , Método Duplo-Cego , Feminino , Testes de Inibição da Hemaglutinação , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Vacinas contra Influenza/administração & dosagem , Masculino , México , Pessoa de Meia-Idade , Placebos/administração & dosagem , Spodoptera , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/efeitos adversos , Vacinas Sintéticas/imunologia , Vacinas Virossomais/administração & dosagem , Vacinas Virossomais/efeitos adversos , Vacinas Virossomais/imunologia , Adulto JovemRESUMO
To explore the evolution of higher order behavioral traits we investigated the organization of foraging patterns in first instar larvae of natural populations of Drosophila. We examined Drosophila simulans (cosmopolitan); D. mauritania (widespread); D. pavani, and D. gaucha (endemic). Larvae of these four species share the same behavior components that comprise foraging (locomotion, feeding, bending, and turning). D. simulans and D. mauritania larvae show uncoupled foraging patterns organized into partially independent behavioral elements. Larvae of D. pavani and D. gaucha exhibit coupled foraging behaviors based on a dependency between behavioral components. Hybrid larvae obtained from crosses of natural populations of D. simulans and D. mauritania show an organization of foraging patterns similar to that of the parental lines. In contrast, hybridization disrupts the organization of foraging patterns in D. pavani and D. gaucha intra- and inter-specific hybrid larvae. This suggests genetic co-adaptation for linkage between the behavioral components that comprise foraging. The organization of larval foraging patterns of the endemic species D. pavani seems readily affected by hybridization. The absence of linkage between behavioral components, as in the case of larval foraging patterns of D. simulans and D. mauritania could lead to an increase in the variability of organization of this higher order behavior. The possibility that larvae may use a variable and flexible behavioral integration of foraging patterns could contribute to their development and feeding in a diversity of substrates and climates.
Assuntos
Drosophila/crescimento & desenvolvimento , Comportamento Alimentar/fisiologia , Larva/fisiologia , Animais , Cruzamentos Genéticos , Drosophila/classificação , Ecossistema , Feminino , Quênia , Masculino , Oviposição , Pupa , SeichelesRESUMO
Flies from two populations of the Chilean endemic neotropical species Drosophila pavani and two populations of its sibling species Drosophila gaucha were crossed reciprocally to obtain intra- and interspecific hybrids. The developmental pathways of locomotor activity and feeding rate were analysed for eleven of twelve possible genotype groups. The hybrids showed reduced fitness indicated by a decrease in the measured traits. Hybrid disadvantage was strongest in interspecific hybrids, especially with respect to feeding behaviour. This evidence supports the contention that D. pavani and D. gaucha have evolved different coadapted gene pools controlling the developmental pathways for behavioural traits expressed during larval foraging; but genetic divergence affecting these behaviours has also taken place between locally adapted populations within each species.
Assuntos
Drosophila/genética , Comportamento Alimentar , Hibridização Genética , Animais , Evolução Biológica , Feminino , Genótipo , Larva , MasculinoRESUMO
Larvae of the sibling species Drosophila simulans and D. mauritiana have rates of locomotor and feeding activity that are closely similar. Comparisons of the trait means for intra- and interspecific hybrids show that significant epistatic interactions affect both characters when the genomes of the two species are combined. The phenotypic variances of progenies obtained by backcrossing the interspecific hybrids to their respective parent species show that appreciable genetic turnover affecting foraging behaviour has occurred since their two phylogenetic lines diverged.
Assuntos
Drosophila/genética , Comportamento Alimentar/fisiologia , Locomoção/fisiologia , Análise de Variância , Animais , Pesos e Medidas Corporais , Drosophila/anatomia & histologia , Drosophila/fisiologia , Epistasia Genética , Genitália/anatomia & histologia , Hibridização Genética , Quênia , Larva/fisiologia , Locomoção/genética , Observação , Especificidade da EspécieRESUMO
O desenvolvimento motor é um fenômeno que permeia a vida de todas as pessoas; ele possibilita a realizaçäo de atos motores essenciais à lida diária näo só por sua excepcionalidade, mas também por sua ubiquidade. De onde vem o nosso entendimento sobre esse fenômeno? O que sabemos hoje sobre ele? Para onde devemos caminhar na busca de novos conhecimentos? Essas säo as questöes abordadas no presente ensaio
Assuntos
Atividade Motora , Destreza MotoraRESUMO
School feeding programs exist in many countries, but few have been properly evaluated. In this study, the short-term effects of breakfast on children's cognitive functions were examined. The subjects were 97 undernourished (weight-for-age < or = -1 SD of reference) and 100 adequately nourished (weight-for-age > -1 SD) children in four primary schools in rural Jamaica. The children were randomly assigned to a group provided with breakfast or a group given a quarter of an orange as a placebo, and the given a battery of four cognitive function tests. After a few weeks the treatments were reversed and the tests repeated. Undernourished children's performance improved significantly on a test of verbal fluency when they received breakfast, whereas that of the adequately nourished children did not change (breakfast x group interaction, P < 0.05). They were no other effects of breakfast on test scores. The findings extend those of a previous Jamaican study conducted under more controlled conditions, and support the targeting of school meals to undernourished children (AU)
Assuntos
Humanos , Criança , Dieta , Distúrbios Nutricionais/fisiopatologia , Fala/fisiologia , Cognição/fisiologia , Estado Nutricional , Jamaica/epidemiologiaRESUMO
An individual's behavior is created by an amalgam of genetic, environmental, cultural, and historical variables working in concert and changing over time. Variations in nutrition are one class of environmental factors. Linking these to outcome effects requires carefully designed studies. Many considerations are involved, and this paper draws attention to some of the fundamental ones. Psychological and behavioral functions tend to be complex, in part because they are affected by a wide range of variables. Almost any given state-a particular constellation of psychological characteristics displayed by an individual at a given time-can be produced in a variety of ways (AU)