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1.
Theor Appl Genet ; 137(6): 120, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38709310

RESUMO

KEY MESSAGE: There is variation in stay-green within barley breeding germplasm, influenced by multiple haplotypes and environmental conditions. The positive genetic correlation between stay-green and yield across multiple environments highlights the potential as a future breeding target. Barley is considered one of the most naturally resilient crops making it an excellent candidate to dissect the genetics of drought adaptive component traits. Stay-green, is thought to contribute to drought adaptation, in which the photosynthetic machinery is maintained for a longer period post-anthesis increasing the photosynthetic duration of the plant. In other cereal crops, including wheat, stay-green has been linked to increased yield under water-limited conditions. Utilizing a panel of diverse barley breeding lines from a commercial breeding program we aimed to characterize stay-green in four environments across two years. Spatiotemporal modeling was used to accurately model senescence patterns from flowering to maturity characterizing the variation for stay-green in barley for the first time. Environmental effects were identified, and multi-environment trait analysis was performed for stay-green characteristics during grain filling. A consistently positive genetic correlation was found between yield and stay-green. Twenty-two chromosomal regions with large effect haplotypes were identified across and within environment types, with ten being identified in multiple environments. In silico stacking of multiple desirable haplotypes showed an opportunity to improve the stay-green phenotype through targeted breeding. This study is the first of its kind to model barley stay-green in a large breeding panel and has detected novel, stable and environment specific haplotypes. This provides a platform for breeders to develop Australian barley with custom senescence profiles for improved drought adaptation.


Assuntos
Secas , Haplótipos , Hordeum , Fenótipo , Melhoramento Vegetal , Hordeum/genética , Hordeum/crescimento & desenvolvimento , Meio Ambiente , Fotossíntese/genética , Locos de Características Quantitativas , Mapeamento Cromossômico
2.
PLoS One ; 19(5): e0299388, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38696456

RESUMO

This study aimed to evaluate the seroprevalence and spatial and temporal clustering of SARS-CoV-2 antibodies in household cats within 63 counties in Illinois from October 2021 to May 2023. The analysis followed a stepwise approach. First, in a choropleth point map, we illustrated the distribution of county-level seroprevalence of SARS-CoV-2 antibodies. Next, spatial interpolation was used to predict the seroprevalence in counties without recorded data. Global and local clustering methods were used to identify the extent of clustering and the counties with high or low seroprevalence, respectively. Next, temporal, spatial, and space-time scan statistic was used to identify periods and counties with higher-than-expected seroprevalence. In the last step, to identify more distinct areas in counties with high seroprevalence, city-level analysis was conducted to identify temporal and space-time clusters. Among 1,715 samples tested by serological assays, 244 samples (14%) tested positive. Young cats had higher seropositivity than older cats, and the third quarter of the year had the highest odds of seropositivity. Three county-level space-time clusters with higher-than-expected seroprevalence were identified in the northeastern, central-east, and southwest regions of Illinois, occurring between June and October 2022. In the city-level analysis, 2 space-time clusters were identified in Chicago's downtown and the southwestern suburbs of Chicago between June and September 2022. Our results suggest that the high density of humans and cats in large cities such as Chicago, might play a role in the transmission and clustering of SARS-CoV-2. Our study provides an in-depth analysis of SARS-CoV-2 epidemiology in Illinois household cats, which will aid in COVID-19 control and prevention.


Assuntos
Anticorpos Antivirais , COVID-19 , SARS-CoV-2 , Análise Espaço-Temporal , Gatos , Animais , Illinois/epidemiologia , Estudos Soroepidemiológicos , SARS-CoV-2/imunologia , COVID-19/epidemiologia , COVID-19/imunologia , Anticorpos Antivirais/sangue , Humanos , Análise por Conglomerados , Feminino , Masculino , Doenças do Gato/epidemiologia , Doenças do Gato/virologia , Doenças do Gato/imunologia
4.
AoB Plants ; 16(2): plae021, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38650718

RESUMO

Mungbean is an important source of plant protein for consumers and a high-value export crop for growers across Asia, Australia and Africa. However, many commercial cultivars are highly vulnerable to biotic stresses, which rapidly reduce yield within the season. Fusarium oxysporum is a soil-borne pathogen that is a growing concern for mungbean growers globally. This pathogen causes Fusarium wilt by infecting the root system of the plant resulting in devastating yield reductions. To understand the impact of Fusarium on mungbean development and productivity and to identify tolerant genotypes, a panel of 23 diverse accessions was studied. Field trials conducted in 2016 and 2021 in Warwick, Queensland, Australia under rainfed conditions investigated the variation in phenology, canopy and yield component traits under disease and disease-free conditions. Analyses revealed a high degree of genetic variation for all traits. By comparing the performance of these traits across these two environments, we identified key traits that underpin yield under disease and disease-free conditions. Aboveground biomass components at 50 % flowering were identified as significant drivers of yield development under disease-free conditions and when impacted by Fusarium resulted in up to 96 % yield reduction. Additionally, eight genotypes were identified to be tolerant to Fusarium. These genotypes were found to display differing phenological and morphological behaviours, thereby demonstrating the potential to breed tolerant lines with a range of diverse trait variations. The identification of tolerant genotypes that sustain yield under disease pressure may be exploited in crop improvement programs.

5.
Curr Treat Options Oncol ; 25(5): 585-604, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38539034

RESUMO

OPINION STATEMENT: Targeted treatment strategies are available for human epidermal growth factor receptor 2 (HER2)-positive (amplified and/or overexpressed) metastatic colorectal cancer (mCRC), and HER2 testing is indicated in patients with mCRC. At present, standard of care first-line treatment for those with HER2-positive mCRC remains chemotherapy in combination with epidermal growth factor receptor (EGFR) inhibitors or bevacizumab, depending on RAS/BRAF mutational status and tumor sidedness. HER2-targeted agents should be considered for those with RAS/BRAF wild-type disease in subsequent-line treatment and in first-line treatment for patients not appropriate for intensive therapy. While the choice of anti-HER2 therapy is empiric given lack of head-to-head comparisons, the combination of trastuzumab plus tucatinib has received FDA accelerated approval for use in this setting and is generally the authors' preference. Trastuzumab plus lapatinib, trastuzumab plus pertuzumab, and trastuzumab deruxtecan (T-DXd) also have evidence of efficacy in this setting. As T-DXd has demonstrated activity following treatment with other HER2-targeted regimens and carries an increased risk of high-grade toxicities, the authors favor reserving it for use after progression on prior anti-HER2 therapy. HER2-targeted therapies that inhibit signal transduction appear to have limited activity in those with RAS mutations, including trastuzumab-containing regimens. However, the antibody drug conjugate T-DXd has some data showing efficacy in this setting, and the authors would consider T-DXd in subsequent-line therapy for HER2-positive, RAS-mutated mCRC. Several areas of uncertainty remain regarding how to best utilize HER2-targeted therapies in mCRC. These include the optimal sequence of anti-HER2 therapies with chemotherapy and anti-EGFR therapies, the optimal combination partners for anti-HER2 therapies, and the incorporation of predictive biomarkers to guide use of anti-HER2 therapies. Results of ongoing studies may thus alter the treatment paradigm above in the coming years.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias Colorretais , Terapia de Alvo Molecular , Receptor ErbB-2 , Humanos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Receptor ErbB-2/metabolismo , Receptor ErbB-2/antagonistas & inibidores , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Metástase Neoplásica , Biomarcadores Tumorais , Gerenciamento Clínico , Resultado do Tratamento , Ensaios Clínicos como Assunto
6.
J Infect Dis ; 229(Supplement_1): S112-S119, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38271230

RESUMO

BACKGROUND: Respiratory syncytial virus (RSV) is a significant cause of infant morbidity and mortality worldwide. Most children experience at least one 1 RSV infection by the age of two 2 years, but not all develop severe disease. However, the understanding of genetic risk factors for severe RSV is incomplete. Consequently, we conducted a genome-wide association study of RSV severity. METHODS: Disease severity was assessed by the ReSVinet scale, in a cohort of 251 infants aged 1 week to 1 year. Genotyping data were collected from multiple European study sites as part of the RESCEU Consortium. Linear regression models were used to assess the impact of genotype on RSV severity and gene expression as measured by microarray. RESULTS: While no SNPs reached the genome-wide statistical significance threshold (P < 5 × 10-8), we identified 816 candidate SNPs with a P-value of <1 × 10-4. Functional annotation of candidate SNPs highlighted genes relevant to neutrophil trafficking and cytoskeletal functions, including LSP1 and RAB27A. Moreover, SNPs within the RAB27A locus significantly altered gene expression (false discovery rate, FDR P < .05). CONCLUSIONS: These findings may provide insights into genetic mechanisms driving severe RSV infection, offering biologically relevant information for future investigations.


Assuntos
Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Lactente , Criança , Humanos , Estudo de Associação Genômica Ampla , Vírus Sincicial Respiratório Humano/genética , Genótipo , Análise em Microsséries
8.
J Learn Disabil ; 57(2): 120-136, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37056038

RESUMO

We report on a school-based randomized control trial study comparing two morphological interventions with untaught controls: one focusing on direct instruction targeting print morphological decoding (direct decoding condition) and the other on inquiry-focused pedagogy using oral morphological analysis (inquiry-analysis condition). We identified 63 Grade 3 children with below-average morphological awareness following screening (from N = 163). This sub-sample showed average pseudoword decoding but poor language and word reading abilities. Following a 13-week supplemental intervention randomized within the 63 children, results showed a statistically significant main effect of intervention on standardized reading vocabulary measures at immediate post-test in the direct decoding condition. Pre-test morphological awareness moderated reading vocabulary effects for the untaught control group. Statistically significant moderation of growth in sentence comprehension at post- by pre-test morphological awareness was also evident in the inquiry-analysis condition. Universal screening for below-average morphological awareness followed by inquiry-based or direct instruction interventions focusing on the meaning dimensions of morphemes may be modestly efficacious for supporting reading vocabulary and sentence comprehension in such at risk learners, potentially aiding school-wide literacy improvement.


Assuntos
Idioma , Vocabulário , Criança , Humanos , Leitura , Alfabetização , Instituições Acadêmicas , Compreensão , Conscientização
9.
J Infect Dis ; 229(Supplement_1): S18-S24, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37712125

RESUMO

BACKGROUND: There is no consensus on how to best quantify disease severity in infants with respiratory syncytial virus (RSV) and/or bronchiolitis; this lack of a sufficiently validated score complicates the provision of clinical care and, the evaluation of trials of therapeutics and vaccines. The ReSVinet score appears to be one of the most promising; however, it is too time consuming to be incorporated into routine clinical care. We aimed to develop and externally validate simplified versions of this score. METHODS: Data from a multinational (the Netherlands, Spain, and United Kingdom) multicenter case-control study of infants with RSV were used to develop simplified versions of the ReSVinet score by conducting a grid search to determine the best combination of equally weighted parameters to maximize for the discriminative ability (measured by area under the receiver operating characteristic curve [AUROC]) across a range of outcomes (hospitalization, intensive care unit admission, ventilation requirement). Subsequently discriminative validity of the score for a range of secondary care outcomes was externally validated by secondary analysis of datasets from Rwanda and Colombia. RESULTS: Three candidate simplified scores were identified using the development dataset; they were excellent (AUROC >0.9) at discriminating for a range of outcomes, and their performance was not significantly different from the original ReSVinet score despite having fewer parameters. In the external validation datasets, the simplified scores were moderate to excellent (AUROC, 0.7-1) across a range of outcomes. In all outcomes, except in a single dataset for predicting admission to the high-dependency unit, they performed at least as well as the original ReSVinet score. CONCLUSIONS: The candidate simplified scores developed require further external validation in larger datasets, ideally from resource-limited settings before any recommendation regarding their use.


Assuntos
Vírus Sincicial Respiratório Humano , Atenção Secundária à Saúde , Lactente , Humanos , Estudos de Casos e Controles , Área Sob a Curva , Colômbia
10.
Clin Transl Med ; 13(12): e1507, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38115705

RESUMO

Whereas most infants infected with respiratory syncytial virus (RSV) show no or only mild symptoms, an estimated 3 million children under five are hospitalized annually due to RSV disease. This study aimed to investigate biological mechanisms and associated biomarkers underlying RSV disease heterogeneity in young infants, enabling the potential to objectively categorize RSV-infected infants according to their medical needs. Immunophenotypic and functional profiling demonstrated the emergence of immature and progenitor-like neutrophils, proliferative monocytes (HLA-DRLow , Ki67+), impaired antigen-presenting function, downregulation of T cell response and low abundance of HLA-DRLow B cells in severe RSV disease. HLA-DRLow monocytes were found as a hallmark of RSV-infected infants requiring hospitalization. Complementary transcriptomics identified genes associated with disease severity and pointed to the emergency myelopoiesis response. These results shed new light on mechanisms underlying the pathogenesis and development of severe RSV disease and identified potential new candidate biomarkers for patient stratification.


Assuntos
Mielopoese , Infecções por Vírus Respiratório Sincicial , Lactente , Criança , Humanos , Mielopoese/genética , Infecções por Vírus Respiratório Sincicial/diagnóstico , Infecções por Vírus Respiratório Sincicial/genética , Vírus Sinciciais Respiratórios , Antígenos HLA-DR , Biomarcadores
11.
BMJ Open ; 13(11): e072938, 2023 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-37963701

RESUMO

INTRODUCTION: Invasive non-typhoidal Salmonellosis (iNTS) is mainly caused by Salmonella enterica serovars Typhimurium and Enteritidis and is estimated to result in 77 500 deaths per year, disproportionately affecting children under 5 years of age in sub-Saharan Africa. Invasive non-typhoidal Salmonellae serovars are increasingly acquiring resistance to first-line antibiotics, thus an effective vaccine would be a valuable tool in reducing morbidity and mortality from infection. While NTS livestock vaccines are in wide use, no licensed vaccines exist for use in humans. Here, a first-in-human study of a novel vaccine (iNTS-GMMA) containing S. Typhimurium and S. Enteritidis Generalised Modules for Membrane Antigens (GMMA) outer membrane vesicles is presented. METHOD AND ANALYSIS: The Salmonella Vaccine Study in Oxford is a randomised placebo-controlled participant-observer blind phase I study of the iNTS-GMMA vaccine. Healthy adult volunteers will be randomised to receive three intramuscular injections of the iNTS-GMMA vaccine, containing equal quantities of S. Typhimurium and S. Enteritidis GMMA particles adsorbed on Alhydrogel, or an Alhydrogel placebo at 0, 2 and 6 months. Participants will be sequentially enrolled into three groups: group 1, 1:1 randomisation to low dose iNTS-GMMA vaccine or placebo; group 2, 1:1 randomisation to full dose iNTS-GMMA vaccine or placebo; group 3, 2:1 randomisation to full dose or lower dose (dependant on DSMC reviews of groups 1 and 2) iNTS-GMMA vaccine or placebo.The primary objective is safety and tolerability of the vaccine. The secondary objective is immunogenicity as measured by O-antigen based ELISA. Further exploratory objectives will characterise the expanded human immune profile. ETHICS AND DISSEMINATION: Ethical approval for this study has been obtained from the South Central-Oxford A Research Ethics Committee (Ethics REF:22/SC/0059). Appropriate documentation and regulatory approvals have been acquired. Results will be disseminated via peer-reviewed articles and conferences. TRIAL REGISTRATION NUMBER: EudraCT Number: 2020-000510-14.


Assuntos
Infecções por Salmonella , Vacinas contra Salmonella , Adulto , Criança , Humanos , Pré-Escolar , Vacinas contra Salmonella/uso terapêutico , Hidróxido de Alumínio , Infecções por Salmonella/prevenção & controle , Infecções por Salmonella/tratamento farmacológico , Salmonella typhimurium , Ensaios Clínicos Controlados Aleatórios como Assunto , Ensaios Clínicos Fase I como Assunto
12.
Behav Brain Res ; 455: 114674, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37722510

RESUMO

RATIONALE: Despite the increasingly pervasive use of chemogenetic tools in preclinical neuroscience research, the in vivo pharmacology of DREADD agonists remains poorly understood. The pharmacological effects of any ligand acting at receptors, engineered or endogenous, are influenced by numerous factors including potency, time course, and receptor selectivity. Thus, rigorous comparison of the potency and time course of available DREADD ligands may provide an empirical foundation for ligand selection. OBJECTIVES: Compare the behavioral pharmacology of three different DREADD ligands clozapine-N-oxide (CNO), compound 21 (C21), and deschloroclozapine (DCZ) in a locomotor activity assay in tyrosine hydroxylase:cre recombinase (TH:Cre) male and female rats. METHODS: Locomotor activity in nine adult TH:Cre Sprague-Dawley rats (5 female, 4 male) was monitored for two hours following administration of d-amphetamine (vehicle, 0.1-3.2 mg/kg, IP), DCZ (vehicle, 0.32-320 µg/kg, IP), CNO (vehicle, 0.32-10 mg/kg), and C21 (vehicle, 0.1-3.2 mg/kg, IP). Behavioral sessions were conducted twice per week prior to and starting three weeks after bilateral intra-VTA hM3Dq DREADD virus injection. RESULTS: d-Amphetamine significantly increased locomotor activity pre- and post-DREADD virus injection. DCZ, CNO, and C21 did not alter locomotor activity pre-DREADD virus injection. There was no significant effect of DCZ, CNO, and C21 on locomotor activity post-DREADD virus injection; however, large individual differences in both behavioral response and receptor expression were observed. CONCLUSIONS: Large individual variability was observed in both DREADD agonist behavioral effects and receptor expression. These results suggest further basic research would facilitate the utility of these chemogenetic tools for behavioral neuroscience research.


Assuntos
Clozapina , Imidazóis , Sulfonamidas , Tiofenos , Área Tegmentar Ventral , Animais , Feminino , Masculino , Ratos , Clozapina/farmacologia , Clozapina/análogos & derivados , Dextroanfetamina , Ligantes , Locomoção , Ratos Sprague-Dawley , Tirosina 3-Mono-Oxigenase/metabolismo , Área Tegmentar Ventral/metabolismo
13.
Front Plant Sci ; 14: 1167221, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37275257

RESUMO

Historically, end-product quality testing has been costly and required large flour samples; therefore, it was generally implemented in the late phases of variety development, imposing a huge cost on the breeding effort and effectiveness. High genetic correlations of end-product quality traits with higher throughput and nondestructive testing technologies, such as near-infrared (NIR), could enable early-stage testing and effective selection of these highly valuable traits in a multi-trait genomic prediction model. We studied the impact on prediction accuracy in genomic best linear unbiased prediction (GBLUP) of adding NIR-predicted secondary traits for six end-product quality traits (crumb yellowness, water absorption, texture hardness, flour yield, grain protein, flour swelling volume). Bread wheat lines (1,400-1,900) were measured across 8 years (2012-2019) for six end-product quality traits with standard laboratory assays and with NIR, which were combined to generate predicted data for approximately 27,000 lines. All lines were genotyped with the Infinium™ Wheat Barley 40K BeadChip and imputed using exome sequence data. End-product and NIR phenotypes were genetically correlated (0.5-0.83, except for flour swelling volume 0.19). Prediction accuracies of end-product traits ranged between 0.28 and 0.64 and increased by 30% through the inclusion of NIR-predicted data compared to single-trait analysis. There was a high correlation between the multi-trait prediction accuracy and genetic correlations between end-product and NIR-predicted data (0.69-0.77). Our forward prediction validation revealed a gradual increase in prediction accuracy when adding more years to the multi-trait model. Overall, we achieved genomic prediction accuracy at a level that enables selection for end-product quality traits early in the breeding cycle.

14.
Exp Clin Psychopharmacol ; 31(6): 1080-1091, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37184942

RESUMO

Clinical amphetamine use is constrained by high abuse potential, and amphetamine use disorder is a persistent clinical problem with no approved medications for its treatment. The opioid antagonist naltrexone has been reported to reduce some abuse-related effects of amphetamine. This study used an amphetamine-versus-food choice procedure in rhesus monkeys and rats to test the hypothesis that naltrexone might serve as either (a) a maintenance medication for amphetamine use disorder treatment or (b) an "abuse-deterrent" adjunct to clinical amphetamine formulations. Male rhesus monkeys and male and female rats were trained to choose between increasing unit doses of intravenous amphetamine and an alternative food reinforcer during daily behavioral sessions. Experiment 1 evaluated effectiveness of continuous naltrexone maintenance to reduce amphetamine-versus-food choice in both monkeys and rats. Experiment 2 combined naltrexone with amphetamine in fixed-proportion amphetamine + naltrexone mixtures to evaluate the effectiveness of naltrexone in both species to reduce mixture choice relative to amphetamine-alone choice. Amphetamine maintained a dose-dependent increase in amphetamine choice in both monkeys and rats. Naltrexone maintenance did not significantly decrease amphetamine choice in either species. Addition of naltrexone to amphetamine reduced amphetamine choices per session in monkeys, but behavior was not reallocated to food choice, and in rats, the addition of naltrexone only decreased food choice without significantly affecting amphetamine choice. These results argue against the use of naltrexone as either (a) a maintenance medication for treatment of amphetamine use disorder or (b) an "abuse-deterrent" adjunct to amphetamine for clinical applications. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Cocaína , Transtornos Relacionados ao Uso de Substâncias , Masculino , Feminino , Ratos , Animais , Anfetamina/farmacologia , Naltrexona/farmacologia , Naltrexona/uso terapêutico , Macaca mulatta , Antagonistas de Entorpecentes/farmacologia , Antagonistas de Entorpecentes/uso terapêutico , Transtornos Relacionados ao Uso de Substâncias/tratamento farmacológico , Comportamento de Escolha , Relação Dose-Resposta a Droga , Autoadministração
15.
BMJ Open ; 13(5): e068966, 2023 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-37225278

RESUMO

INTRODUCTION: This is the first efficacy study of an oral live attenuated vaccine against Salmonella Paratyphi A using a human challenge model of paratyphoid infection. S. Paratyphi A is responsible for 3.3 million cases of enteric fever every year, with over 19 000 deaths. Although improvements to sanitation and access to clean water are vital to reduce the burden of this condition, vaccination offers a cost-effective, medium-term solution. Efficacy trials of potential S. Paratyphi vaccine candidates in the field are unlikely to be feasible given the large number of participants required. Human challenge models therefore offer a unique, cost-effective solution to test efficacy of such vaccines. METHODS AND ANALYSIS: This is an observer-blind, randomised, placebo-controlled trial phase I/II of the oral live-attenuated vaccine against S. Paratyphi A, CVD 1902. Volunteers will be randomised 1:1 to receive two doses of CVD 1902 or placebo, 14 days apart. One month following second vaccination all volunteers will ingest S. Paratyphi A bacteria with a bicarbonate buffer solution. They will be reviewed daily in the following 14 days and diagnosed with paratyphoid infection if the predefined microbiological or clinical diagnostic criteria are met. All participants will be treated with antibiotics on diagnosis, or at day 14 postchallenge if not diagnosed. The vaccine efficacy will be determined by comparing the relative attack rate, that is, the proportion of those diagnosed with paratyphoid infection, in the vaccine and placebo groups. ETHICS AND DISSEMINATION: Ethical approval for this study has been obtained from the Berkshire Medical Research Ethics Committee (REC ref 21/SC/0330). The results will be disseminated via publication in a peer-reviewed journal and presentation at international conferences. TRIAL REGISTRATION NUMBER: ISRCTN15485902.


Assuntos
Doenças Cardiovasculares , Salmonella paratyphi A , Humanos , Adulto , Vacinas Atenuadas , Voluntários Saudáveis , Voluntários , Ensaios Clínicos Controlados Aleatórios como Assunto , Ensaios Clínicos Fase I como Assunto
17.
Theor Appl Genet ; 136(5): 99, 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37027025

RESUMO

KEY MESSAGE: The reaction norm analysis of stability can be enhanced by partitioning the contribution of different types of G × E to the variation in slope. The slope of regression in a reaction norm model, where the performance of a genotype is regressed over an environmental covariable, is often used as a measure of stability of genotype performance. This method could be developed further by partitioning variation in the slope of regression into the two sources of genotype-by-environment interaction (G × E) which cause it: scale-type G × E (heterogeneity of variance) and rank-type G × E (heterogeneity of correlation). Because the two types of G × E have very different properties, separating their effect would enable a clearer understanding of stability. The aim of this paper was to demonstrate two methods which seek to achieve this in reaction norm models. Reaction norm models were fit to yield data from a multi-environment trial in Barley (Hordeum vulgare), with the adjusted mean yield from each environment used as the environmental covariable. Stability estimated from factor-analytic models, which can disentangle the two types of G × E and estimate stability based on rank-type G × E, was used for comparison. Adjusting the reaction norm slope to account for scale-type G × E using a genetic regression more than tripled the correlation with factor-analytic estimates of stability (0.24-0.26 to 0.80-0.85), indicating that it removed variation in the reaction norm slope that originated from scale-type G × E. A standardisation procedure had a more modest increase (055-0.59) but could be useful when curvilinear reaction norms are required. Analyses which use reaction norms to explore the stability of genotypes could gain additional insight into the mechanisms of stability by applying the methods outlined in this study.


Assuntos
Meio Ambiente , Interação Gene-Ambiente , Modelos Genéticos , Melhoramento Vegetal , Genótipo
18.
J Infect ; 86(6): 574-583, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37028454

RESUMO

BACKGROUND: Heterologous COVID vaccine priming schedules are immunogenic and effective. This report aims to understand the persistence of immune response to the viral vectored, mRNA and protein-based COVID-19 vaccine platforms used in homologous and heterologous priming combinations, which will inform the choice of vaccine platform in future vaccine development. METHODS: Com-COV2 was a single-blinded trial in which adults ≥ 50 years, previously immunised with single dose 'ChAd' (ChAdOx1 nCoV-19, AZD1222, Vaxzevria, Astrazeneca) or 'BNT' (BNT162b2, tozinameran, Comirnaty, Pfizer/BioNTech), were randomised 1:1:1 to receive a second dose 8-12 weeks later with either the homologous vaccine, or 'Mod' (mRNA-1273, Spikevax, Moderna) or 'NVX' (NVX-CoV2373, Nuvaxovid, Novavax). Immunological follow-up and the secondary objective of safety monitoring were performed over nine months. Analyses of antibody and cellular assays were performed on an intention-to-treat population without evidence of COVID-19 infection at baseline or for the trial duration. FINDINGS: In April/May 2021, 1072 participants were enrolled at a median of 9.4 weeks after receipt of a single dose of ChAd (N = 540, 45% female) or BNT (N = 532, 39% female) as part of the national vaccination programme. In ChAd-primed participants, ChAd/Mod had the highest anti-spike IgG from day 28 through to 6 months, although the heterologous vs homologous geometric mean ratio (GMR) dropped from 9.7 (95% CI (confidence interval): 8.2, 11.5) at D28 to 6.2 (95% CI: 5.0, 7.7) at D196. The heterologous/homologous GMR for ChAd/NVX similarly dropped from 3.0 (95% CI:2.5,3.5) to 2.4 (95% CI:1.9, 3.0). In BNT-primed participants, decay was similar between heterologous and homologous schedules with BNT/Mod inducing the highest anti-spike IgG for the duration of follow-up. The adjusted GMR (aGMR) for BNT/Mod compared with BNT/BNT increased from 1.36 (95% CI: 1.17, 1.58) at D28 to 1.52 (95% CI: 1.21, 1.90) at D196, whilst for BNT/NVX this aGMR was 0.55 (95% CI: 0.47, 0.64) at day 28 and 0.62 (95% CI: 0.49, 0.78) at day 196. Heterologous ChAd-primed schedules produced and maintained the largest T-cell responses until D196. Immunisation with BNT/NVX generated a qualitatively different antibody response to BNT/BNT, with the total IgG significantly lower than BNT/BNT during all follow-up time points, but similar levels of neutralising antibodies. INTERPRETATION: Heterologous ChAd-primed schedules remain more immunogenic over time in comparison to ChAd/ChAd. BNT-primed schedules with a second dose of either mRNA vaccine also remain more immunogenic over time in comparison to BNT/NVX. The emerging data on mixed schedules using the novel vaccine platforms deployed in the COVID-19 pandemic, suggest that heterologous priming schedules might be considered as a viable option sooner in future pandemics. ISRCTN: 27841311 EudraCT:2021-001275-16.


Assuntos
COVID-19 , Vacinas , Adulto , Feminino , Humanos , Masculino , Vacinas contra COVID-19 , ChAdOx1 nCoV-19 , Vacina BNT162 , Pandemias , Método Simples-Cego , COVID-19/prevenção & controle , Vacinação , Imunidade , Imunoglobulina G , Anticorpos Antivirais
19.
Vaccine ; 41(19): 3019-3023, 2023 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-37045683

RESUMO

In January 2020 the UK changed from a 2 + 1 schedule for 13-valent pneumococcal conjugate vaccine (PCV13) to a 1 + 1 schedule (doses at 3 and 12 months) based on a randomized immunogenicity trial comparing the two schedules. Carriage prevalence measured at the time of booster and 6 months later in 191 of the 213 study infants was 57 % (109/191) and 60 % (114/190) respectively. There were eight episodes of vaccine-type (VT) or vaccine-related 6C carriage in the 2 + 1 and six in the 1 + 1 group; ≥4-fold rises in serotype-specific IgG in 71 children with paired post-booster and follow up blood samples at 21-33 months of age were found in 20 % (7/35) of the 2 + 1 and 15 % (6/41) of the 1 + 1 group. VTs identified in carriage and inferred from serology were similar comprising 3, 19A and 19F. Dropping a priming dose from the 2 + 1 PCV 13 schedule did not increase VT carriage in the study cohort. Ongoing population level carriage studies will be important to confirm this.


Assuntos
Infecções Pneumocócicas , Criança , Humanos , Lactente , Anticorpos Antibacterianos , Esquemas de Imunização , Nasofaringe , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas , Streptococcus pneumoniae , Reino Unido/epidemiologia , Vacinas Conjugadas
20.
Vaccine ; 41(16): 2707-2715, 2023 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-36941154

RESUMO

BACKGROUND: Respiratory syncytial virus (RSV) causes a considerable disease burden in young children globally, but reliable estimates of RSV-related costs and health-related quality-of-life (HRQoL) are scarce. This study aimed to evaluate the RSV-associated costs and HRQoL effects in infants and their caregivers in four European countries. METHODS: Healthy term-born infants were recruited at birth and actively followed up in four European countries. Symptomatic infants were systematically tested for RSV. Caregivers recorded the daily HRQoL of their child and themselves, measured by a modified EQ-5D with Visual Analogue Scale, for 14 consecutive days or until symptoms resolved. At the end of each RSV episode, caregivers reported healthcare resource use and work absenteeism. Direct medical costs per RSV episode were estimated from a healthcare payer's perspective and indirect costs were estimated from a societal perspective. Means and 95% confidence intervals (CI) of direct medical costs, total costs (direct costs + productivity loss) and quality-adjusted life-day (QALD) loss per RSV episode were estimated per RSV episode, as well as per subgroup (medical attendance, country). RESULTS: Our cohort of 1041 infants experienced 265 RSV episodes with a mean symptom duration of 12.5 days. The mean (95% CI) cost per RSV episode was €399.5 (242.3, 584.2) and €494.3 (317.7, 696.1) from the healthcare payer's and societal perspective, respectively. The mean QALD loss per RSV episode of 1.9 (1.7, 2.1) was independent of medical attendance (in contrast to costs, which also differed by country). Caregiver and infant HRQoL evolved similarly. CONCLUSION: This study fills essential gaps for future economic evaluations by prospectively estimating direct and indirect costs and HRQoL effects on healthy term infants and caregivers separately, for both medically attended (MA) and non-MA laboratory-confirmed RSV episodes. We generally observed greater HRQoL losses than in previous studies which used non-community and/or non-prospective designs.


Assuntos
Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Criança , Recém-Nascido , Humanos , Lactente , Pré-Escolar , Infecções por Vírus Respiratório Sincicial/epidemiologia , Estresse Financeiro , Estudos Prospectivos , Assistência ao Paciente , Custos de Cuidados de Saúde , Inquéritos e Questionários , Qualidade de Vida , Europa (Continente)/epidemiologia , Hospitalização
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