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1.
Bioorg Chem ; 148: 107414, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38733748

RESUMO

Spectroscopic, biochemical, and computational modelling studies have been used to assess the binding capability of a set of minor groove binding (MGB) ligands against the self-complementary DNA sequences 5'-d(CGCACTAGTGCG)-3' and 5'-d(CGCAGTACTGCG)-3'. The ligands were carefully designed to target the DNA response element, 5'-WGWWCW-3', the binding site for several nuclear receptors. Basic 1D 1H NMR spectra of the DNA samples prepared with three MGB ligands show subtle variations suggestive of how each ligand associates with the double helical structure of both DNA sequences. The variations among the investigated ligands were reflected in the line shape and intensity of 1D 1H and 31P-{1H} NMR spectra. Rapid visual inspection of these 1D NMR spectra proves to be beneficial in providing valuable insights on MGB binding molecules. The NMR results were consistent with the findings from both UV DNA denaturation and molecular modelling studies. Both the NMR spectroscopic and computational analyses indicate that the investigated ligands bind to the minor grooves as antiparallel side-by-side dimers in a head-to-tail fashion. Moreover, comparisons with results from biochemical studies offered valuable insights into the mechanism of action, and antitumor activity of MGBs in relation to their structures, essential pre-requisites for future optimization of MGBs as therapeutic agents.


Assuntos
DNA , DNA/química , DNA/metabolismo , Ligantes , Humanos , Antineoplásicos/química , Antineoplásicos/farmacologia , Estrutura Molecular , Conformação de Ácido Nucleico , Sítios de Ligação , Relação Estrutura-Atividade , Modelos Moleculares , Relação Dose-Resposta a Droga , Espectroscopia de Ressonância Magnética , Linhagem Celular Tumoral
2.
Eur J Appl Physiol ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38634901

RESUMO

PURPOSE: The purpose was to examine the effects of 8-weeks (3 days/week) of linear periodization resistance exercise training (RET) on neuromuscular function in prepubescent youth. METHODS: Twenty-five healthy prepubescent youth (11 males, 14 females, age = 9.1 ± 0.8 years) completed the RET (n = 17) or served as controls (CON, n = 8). Isometric maximal voluntary contractions (MVCs) and trapezoidal submaximal contractions at 35 and 60% MVC of the right leg extensors were performed with surface electromyography (EMG) recorded from the leg extensors [vastus lateralis (VL), rectus femoris, and vastus medialis] and flexors (biceps femoris and semitendinosus). EMG amplitude of the leg extensors and flexors were calculated during the MVCs. Motor unit (MU) action potential trains were decomposed from the surface EMG of the VL for the 35 and 60% MVCs. MU firing rates and action potential amplitudes were regressed against recruitment threshold with the y-intercepts and slopes calculated for each contraction. Total leg extensor muscle cross-sectional area (CSA) was collected using ultrasound images. ANOVA models were used to examine potential differences. RESULTS: Isometric strength increased post-RET (P = 0.006) with no changes in leg extensor and flexor EMG amplitude. Furthermore, there were no changes in total CSA or the MU action potential amplitude vs. recruitment threshold relationships. However, there were increases in the firing rates of the higher-threshold MUs post-RET as indicated with greater y-intercepts (P = 0.003) from the 60% MVC and less negative slope (P = 0.004) of the firing rates vs. recruitment threshold relationships at 35% MVC. CONCLUSIONS: MU adaptations contribute to strength increases following RET in prepubescent youth.

3.
Infect Immun ; 91(3): e0053822, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36847490

RESUMO

Staphylococcus aureus generates biofilms during many chronic human infections, which contributes to its growth and persistence in the host. Multiple genes and pathways necessary for S. aureus biofilm production have been identified, but knowledge is incomplete, and little is known about spontaneous mutations that increase biofilm formation as infection progresses. Here, we performed in vitro selection of four S. aureus laboratory strains (ATCC 29213, JE2, N315, and Newman) to identify mutations associated with enhanced biofilm production. Biofilm formation increased in passaged isolates from all strains, exhibiting from 1.2- to 5-fold the capacity of parental lines. Whole-genome sequencing identified nonsynonymous mutations affecting 23 candidate genes and a genomic duplication encompassing sigB. Six candidate genes significantly impacted biofilm formation as isogenic transposon knockouts: three were previously reported to impact S. aureus biofilm formation (icaR, spdC, and codY), while the remaining three (manA, narH, and fruB) were newly implicated by this study. Plasmid-mediated genetic complementation of manA, narH, and fruB transposon mutants corrected biofilm deficiencies, with high-level expression of manA and fruB further enhancing biofilm formation over basal levels. This work recognizes genes not previously identified as contributing to biofilm formation in S. aureus and reveals genetic changes able to augment biofilm production by that organism.


Assuntos
Infecções Estafilocócicas , Staphylococcus aureus , Humanos , Staphylococcus aureus/metabolismo , Plasmídeos , Mutação , Biofilmes
4.
Glob Chang Biol ; 28(22): 6586-6601, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35978484

RESUMO

Projecting the future distributions of commercially and ecologically important species has become a critical approach for ecosystem managers to strategically anticipate change, but large uncertainties in projections limit climate adaptation planning. Although distribution projections are primarily used to understand the scope of potential change-rather than accurately predict specific outcomes-it is nonetheless essential to understand where and why projections can give implausible results and to identify which processes contribute to uncertainty. Here, we use a series of simulated species distributions, an ensemble of 252 species distribution models, and an ensemble of three regional ocean climate projections, to isolate the influences of uncertainty from earth system model spread and from ecological modeling. The simulations encompass marine species with different functional traits and ecological preferences to more broadly address resource manager and fishery stakeholder needs, and provide a simulated true state with which to evaluate projections. We present our results relative to the degree of environmental extrapolation from historical conditions, which helps facilitate interpretation by ecological modelers working in diverse systems. We found uncertainty associated with species distribution models can exceed uncertainty generated from diverging earth system models (up to 70% of total uncertainty by 2100), and that this result was consistent across species traits. Species distribution model uncertainty increased through time and was primarily related to the degree to which models extrapolated into novel environmental conditions but moderated by how well models captured the underlying dynamics driving species distributions. The predictive power of simulated species distribution models remained relatively high in the first 30 years of projections, in alignment with the time period in which stakeholders make strategic decisions based on climate information. By understanding sources of uncertainty, and how they change at different forecast horizons, we provide recommendations for projecting species distribution models under global climate change.


Assuntos
Mudança Climática , Ecossistema , Pesqueiros , Previsões , Incerteza
5.
CMAJ ; 194(17): E601-E607, 2022 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-35500919

RESUMO

BACKGROUND: Regular cancer surveillance is crucial for understanding where progress is being made and where more must be done. We sought to provide an overview of the expected burden of cancer in Canada in 2022. METHODS: We obtained data on new cancer incidence from the National Cancer Incidence Reporting System (1984-1991) and Canadian Cancer Registry (1992-2018). Mortality data (1984-2019) were obtained from the Canadian Vital Statistics - Death Database. We projected cancer incidence and mortality counts and rates to 2022 for 22 cancer types by sex and province or territory. Rates were age standardized to the 2011 Canadian standard population. RESULTS: An estimated 233 900 new cancer cases and 85 100 cancer deaths are expected in Canada in 2022. We expect the most commonly diagnosed cancers to be lung overall (30 000), breast in females (28 600) and prostate in males (24 600). We also expect lung cancer to be the leading cause of cancer death, accounting for 24.3% of all cancer deaths, followed by colorectal (11.0%), pancreatic (6.7%) and breast cancers (6.5%). Incidence and mortality rates are generally expected to be higher in the eastern provinces of Canada than the western provinces. INTERPRETATION: Although overall cancer rates are declining, the number of cases and deaths continues to climb, owing to population growth and the aging population. The projected high burden of lung cancer indicates a need for increased tobacco control and improvements in early detection and treatment. Success in breast and colorectal cancer screening and treatment likely account for the continued decline in their burden. The limited progress in early detection and new treatments for pancreatic cancer explains why it is expected to be the third leading cause of cancer death in Canada.


Assuntos
Neoplasias Pulmonares , Idoso , Canadá/epidemiologia , Feminino , Previsões , Humanos , Incidência , Neoplasias Pulmonares/epidemiologia , Masculino , Sistema de Registros
6.
Am J Respir Crit Care Med ; 203(9): 1127-1137, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33296290

RESUMO

Rationale:Staphylococcus aureus is the most common respiratory pathogen isolated from patients with cystic fibrosis (CF) in the United States. Although modes of acquisition and genetic adaptation have been described for Pseudomonas aeruginosa, resulting in improved diagnosis and treatment, these features remain more poorly defined for S. aureus.Objectives: To characterize the molecular epidemiology and genetic adaptation of S. aureus during chronic CF airway infection and in response to antibiotic therapy.Methods: We performed whole-genome sequencing of 1,382 S. aureus isolates collected longitudinally over a mean 2.2 years from 246 children with CF at five U.S. centers between 2008 and 2017. Results were integrated with clinical and demographic data to characterize bacterial population dynamics and identify common genetic targets of in vivo adaptation.Measurements and Main Results: Results showed that 45.5% of patients carried multiple, coexisting S. aureus lineages, often having different antibiotic susceptibility profiles. Adaptation during the course of infection commonly occurred in a set of genes related to persistence and antimicrobial resistance. Individual sequence types demonstrated wide geographic distribution, and we identified limited strain-sharing among children linked by common household or clinical exposures. Unlike P. aeruginosa, S. aureus genetic diversity was unconstrained, with an ongoing flow of new genetic elements into the population of isolates from children with CF.Conclusions: CF airways are frequently coinfected by multiple, genetically distinct S. aureus lineages, indicating that current clinical procedures for sampling isolates and selecting antibiotics are likely inadequate. Strains can be shared by patients in close domestic or clinical contact and can undergo convergent evolution in key persistence and antimicrobial-resistance genes, suggesting novel diagnostic and therapeutic approaches for future study.


Assuntos
Fibrose Cística/complicações , Fibrose Cística/microbiologia , Infecções Respiratórias/microbiologia , Infecções Estafilocócicas/genética , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/genética , Adolescente , Antibacterianos/uso terapêutico , Criança , Estudos de Coortes , Feminino , Humanos , Masculino , Epidemiologia Molecular , Infecções Respiratórias/tratamento farmacológico , Infecções Respiratórias/genética , Infecções Estafilocócicas/tratamento farmacológico
7.
J Antimicrob Chemother ; 75(5): 1182-1186, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32016379

RESUMO

BACKGROUND: Glycopeptides (GPs), lipopeptides (LPs) and lipoglycopeptides (LGPs) are related antimicrobials important for the management of invasive MRSA infections. Cross-resistance among these antibiotics in MRSA is well documented, as is the observation that susceptibility of MRSA to ß-lactams increases as susceptibility to GPs and LPs decreases (i.e. the seesaw effect). Efforts to understand the relationship between GP/LP/LGP cross-resistance and the seesaw effect have focused on the PBPs, but the role of lipid metabolism has not been investigated. OBJECTIVES: Since the cell membrane is structurally and metabolically integrated with the cell wall and anchors associated proteins, including PBPs, we examined the relationship between membrane lipid composition and the phenomena of cross-resistance among GPs/LPs/LGPs and the ß-lactam seesaw effect. METHODS: We selected for daptomycin, vancomycin and dalbavancin resistance using the USA300 strain JE2 and evaluated the resulting mutants by WGS, MS-based lipidomics and antimicrobial susceptibility testing to assess the relationship between membrane composition, cross-resistance, and the seesaw effect. RESULTS: We observed cross-resistance to GPs/LPs/LGPs among the selected strains and the seesaw effect against various ß-lactams, depending on the PBP targets of the particular ß-lactam. We found that modification of membrane composition occurs not only in daptomycin-selected strains, but also vancomycin- and dalbavancin-selected strains. Significantly, we observed that the abundance of most phosphatidylglycerols positively correlates with MICs of GPs/LPs/LGPs and negatively correlates with the MICs of ß-lactams. CONCLUSIONS: These studies demonstrate a major association between membrane remodelling, cross-resistance and the seesaw effect.


Assuntos
Staphylococcus aureus Resistente à Meticilina , beta-Lactamas , Antibacterianos/farmacologia , Glicopeptídeos/farmacologia , Lipoglicopeptídeos , Lipopeptídeos , Testes de Sensibilidade Microbiana , Fosfatidilgliceróis , beta-Lactamas/farmacologia
8.
Infect Immun ; 87(4)2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30642903

RESUMO

Adaptation of Staphylococcus aureus to host microenvironments during chronic infection involves spontaneous mutations, yet changes underlying adaptive phenotypes remain incompletely explored. Here, we employed artificial selection and whole-genome sequencing to better characterize spontaneous chromosomal mutations that alter two pathogenicity phenotypes relevant to chronic infection in S. aureus: intracellular invasiveness and intracellular cytotoxicity. We identified 23 genes whose alteration coincided with enhanced virulence, 11 that were previously known and 12 (52%) that had no previously described role in S. aureus pathogenicity. Using precision genome editing, transposon mutants, and gene complementation, we empirically assessed the contributions of individual genes to the two virulence phenotypes. We functionally validated 14 of 21 genes tested as measurably influencing invasion and/or cytotoxicity, including 8 newly implicated by this study. We identified inactivating mutations (murA, ndhC, and a hypothetical membrane protein) and gain-of-function mutations (aroE Thr182Ile, yhcF Thr74Ile, and Asp486Glu in a hypothetical peptidase) in previously unrecognized S. aureus virulence genes that enhance pathogenesis when introduced into a clean genetic background, as well as a novel activating mutation in the known virulence regulator gene saeS (Ala106Thr). Investigation of potentially epistatic interactions identified a tufA mutation (Ala271Val) that enhances virulence only in the context of purine operon repressor gene (purR) inactivation. This project reveals a functionally diverse range of genes affected by gain- or loss-of-function mutations that contribute to S. aureus adaptive virulence phenotypes. More generally, the work establishes artificial selection as a means to determine the genetic mechanisms underlying complex bacterial phenotypes relevant to adaptation during infection.


Assuntos
Proteínas de Bactérias/genética , Mutação , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/genética , Staphylococcus aureus/patogenicidade , Proteínas de Bactérias/metabolismo , Doença Crônica , Humanos , Staphylococcus aureus/metabolismo , Virulência , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Sequenciamento Completo do Genoma
9.
Artigo em Inglês | MEDLINE | ID: mdl-31285231

RESUMO

Inhaled aztreonam is increasingly used for chronic Pseudomonas aeruginosa suppression in patients with cystic fibrosis (CF), but the potential for that organism to evolve aztreonam resistance remains incompletely explored. Here, we performed genomic analysis of clonally related pre- and posttreatment CF clinical isolate pairs to identify genes that are under positive selection during aztreonam therapy in vivo We identified 16 frequently mutated genes associated with aztreonam resistance, the most prevalent being ftsI and ampC, and 13 of which increased aztreonam resistance when introduced as single gene transposon mutants. Several previously implicated aztreonam resistance genes were found to be under positive selection in clinical isolates even in the absence of inhaled aztreonam exposure, indicating that other selective pressures in the cystic fibrosis airway can promote aztreonam resistance. Given its potential to confer plasmid-mediated resistance, we further characterized mutant ampC alleles and performed artificial evolution of ampC for maximal activity against aztreonam. We found that naturally occurring ampC mutants conferred variably increased resistance to aztreonam (2- to 64-fold) and other ß-lactam agents but that its maximal evolutionary capacity for hydrolyzing aztreonam was considerably higher (512- to 1,024-fold increases) and was achieved while maintaining or increasing resistance to other drugs. These studies implicate novel chromosomal aztreonam resistance determinants while highlighting that different mutations are favored during selection in vivo and in vitro, show that ampC has a high maximal potential to hydrolyze aztreonam, and provide an approach to disambiguate mutations promoting specific resistance phenotypes from those more generally increasing bacterial fitness in vivo.


Assuntos
Proteínas de Bactérias/genética , Fibrose Cística/tratamento farmacológico , Peptidoglicano Glicosiltransferase/genética , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/genética , Resistência beta-Lactâmica/genética , beta-Lactamases/genética , Administração por Inalação , Antibacterianos/metabolismo , Antibacterianos/uso terapêutico , Aztreonam/metabolismo , Aztreonam/uso terapêutico , Fibrose Cística/microbiologia , Fibrose Cística/patologia , Elementos de DNA Transponíveis , Expressão Gênica , Humanos , Mutação , Infecções por Pseudomonas/microbiologia , Infecções por Pseudomonas/patologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/enzimologia , Pseudomonas aeruginosa/isolamento & purificação , Seleção Genética
10.
Prev Med ; 122: 148-154, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31078168

RESUMO

With a strong focus on end user, or knowledge user, engagement throughout the study, an integrated knowledge translation approach (iKT) is expected to enhance the quality, relevance and reach of research findings. From its initiation, the Canadian Population Attributable Risk of Cancer (ComPARe) study combined the expertise of the knowledge producers (cancer prevention researchers) and select knowledge users in an iKT approach. We describe in detail our iKT approach, including governance, outputs and early reflections. In our model, knowledge users were integrated as members of the research team or members of a KT Advisory Committee. The integrated knowledge users took a lead role on the KT activities for ComPARe, including developing the KT Blueprint, a four phase systematic approach to guide the planning and implementation of KT activities. This approach included planning, knowledge product development, dissemination and evaluation, with advisory committee engagement built in throughout. Our early reflections identified enablers and challenges of an iKT approach for this study. Enablers included co-investigators' commitment and attitude towards iKT, support for iKT from the funding agency, an established partnership early on, understanding of and experience in each other's area of expertise, dedicated funding, clearly delineated roles, advisory committee buy-in and existing tools. Challenges included anticipating all costs, continuity of involvement, competing priorities, relationship management and geographic distance. A future evaluation will determine the effectiveness and impact of the iKT approach and KT Blueprint. In the interim, the approach we describe here can be modeled by others interested in collaborative, action-oriented research.


Assuntos
Comportamento Cooperativo , Prestação Integrada de Cuidados de Saúde , Neoplasias/epidemiologia , Pesquisadores , Pesquisa Translacional Biomédica , Canadá , Humanos , Neoplasias/etiologia , Neoplasias/prevenção & controle
11.
J Pediatr Gastroenterol Nutr ; 69(2): 182-188, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31107405

RESUMO

OBJECTIVES: The incidence of pediatric inflammatory bowel disease (IBD) is increasing worldwide. Ecological studies show higher incidence in regions at higher latitude or lower ambient ultraviolet radiation; individual-level associations with sun exposure have not been assessed. METHODS: We recruited children (0-17 years) with IBD from 2 large hospitals in Melbourne, Australia. Control participants were recruited from the day surgery unit of one of the same hospitals. Questionnaires provided data on demographics, past sun exposure, the likelihood of sunburn (skin sensitivity) or tanning following sun exposure, use of sun protection, physical activity, and parental smoking and education. Grandparent ancestry was used to determine participant ethnicity. Cases and controls were matched on age and sex. We used conditional logistic regression to test the association between being an IBD case and past sun exposure at different ages, adjusted for a range of other factors. RESULTS: After matching, n = 99 cases and n = 396 controls were included in the analysis. In multivariable analysis, for each 10 min increment in leisure-time sun exposure in summer or winter there was a linear 6% reduction in the odds of having IBD (P = 0.002). Results were similar in sensitivity analyses including only the most recently diagnosed cases, only Caucasian cases and controls, only those with symptom onset within the year before study entry, or additionally adjusted for age or physical activity. CONCLUSIONS: Higher sun exposure in the previous summer or winter was associated with a reduced risk of having IBD. There are plausible pathways that could mediate this effect.


Assuntos
Doenças Inflamatórias Intestinais/epidemiologia , Luz Solar , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Doenças Inflamatórias Intestinais/etiologia , Masculino , Análise de Regressão , Fatores de Risco , Estações do Ano , Vitória/epidemiologia
13.
Environ Monit Assess ; 190(9): 530, 2018 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-30121848

RESUMO

Quantifying the impacts of disturbances such as oil spills on marine species can be challenging. Natural environmental variability, human responses to the disturbance (e.g., fisheries closures), the complex life histories of the species being monitored, and limited pre-spill data can make detection of effects of oil spills difficult. Using long-term monitoring data from the state of Louisiana (USA), we applied novel spatiotemporal approaches to identify anomalies in species occurrence and catch rates. We included covariates (salinity, temperature, turbidity) to help isolate unusual events. While some species showed evidence of unlikely temporal anomalies in occurrence or catch rates, we found that the majority of the observed anomalies were also before the Deepwater Horizon event. Several species-gear combinations suggested upticks in the spatial variability immediately following the spill, but most species indicated no trend. Across species-gear combinations, there was no clear evidence for synchronous or asynchronous responses in occurrence or catch rates across sites following the spill. Our results are in general agreement to other analyses of monitoring data that detected small impacts, but in contrast to recent results from ecological modeling that showed much larger effects of the oil spill on fish and shellfish.


Assuntos
Pesqueiros/estatística & dados numéricos , Peixes/fisiologia , Poluição por Petróleo/análise , Poluentes Químicos da Água/análise , Animais , Monitoramento Ambiental , Golfo do México , Humanos , Louisiana , Alimentos Marinhos/análise , Análise Espaço-Temporal , Poluição Química da Água/estatística & dados numéricos
14.
Glob Chang Biol ; 21(4): 1482-96, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25430731

RESUMO

Changing climate extremes and invasion by non-native species are two of the most prominent threats to native faunas. Predicting the relationships between global change and native faunas requires a quantitative toolkit that effectively links the timing and magnitude of extreme events to variation in species abundances. Here, we examine how discharge anomalies--unexpected floods and droughts--determine covariation in abundance of native and non-native fish species in a highly variable desert river in Arizona. We quantified stochastic variation in discharge using Fourier analyses on >15,000 daily observations. We subsequently coupled maximum annual spectral anomalies with a 15-year time series of fish abundances (1994-2008), using Multivariate Autoregressive State-Space (MARSS) models. Abiotic drivers (discharge anomalies) were paramount in determining long-term fish abundances, whereas biotic drivers (species interactions) played only a secondary role. As predicted, anomalous droughts reduced the abundances of native species, while floods increased them. However, in contrast to previous studies, we observed that the non-native assemblage was surprisingly unresponsive to extreme events. Biological trait analyses showed that functional uniqueness was higher in native than in non-native fishes. We also found that discharge anomalies influenced diversity patterns at the meta-community level, with nestedness increasing after anomalous droughts due to the differential impairment of native species. Overall, our results advance the notion that discharge variation is key in determining community trajectories in the long term, predicting the persistence of native fauna even in the face of invasion. We suggest this variation, rather than biotic interactions, may commonly underlie covariation between native and non-native faunas, especially in highly variable environments. If droughts become increasingly severe due to climate change, and floods increasingly muted due to regulation, fish assemblages in desert rivers may become taxonomically and functionally impoverished and dominated by non-native taxa.


Assuntos
Biodiversidade , Secas , Peixes/fisiologia , Rios , Animais , Arizona , Clima Desértico , Inundações , Análise de Fourier , Espécies Introduzidas , Modelos Biológicos , Análise Multivariada , Densidade Demográfica
15.
Ecol Appl ; 25(4): 1157-65, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26465049

RESUMO

Forecasting the risk of population decline is crucial in the realm of biological conservation and figures prominently in population viability analyses (PVA). A common form of available data for a PVA is population counts through time. Previous research has suggested that improving estimates of population trends and risk from count data depends on longer observation periods, but that is often impractical or undesirable. Making multiple observations within a single time step is an alternative way to gather more data without extending the observation period. In this paper, we examine the trade-off between the length of the time period over which observations of the population have been taken and the total number of observations or samples that have been recorded through an analysis of simulated data. We found that when the ratio of process error to measurement error variance is high, more precise estimates of quasi-extinction risks can be obtained if replicated observations are taken at each time step, but when the ratio is low, replicated observations add little benefit in improving precision. These results can be used to efficiently design effective monitoring schemes for species of conservation concern.


Assuntos
Extinção Biológica , Previsões/métodos , Modelos Biológicos , Animais , Simulação por Computador , Dinâmica Populacional/tendências , Fatores de Tempo
16.
Patient Educ Couns ; 118: 108023, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37866073

RESUMO

OBJECTIVE: Patient feedback is rarely gathered systematically in cognitive rehabilitation research. This study examined the perceptions and experiences of people with traumatic brain injury (TBI) who participated in a trial of a 6-session educational program for the rehabilitation of prospective memory (PM) impairment. METHODS: A mixed methods design was used with 47 participants with TBI who completed a compensatory strategy training program (COMP) or COMP plus metacognitive strategy training program (COMP-MST) delivered by an occupational therapist. Data were collected via a participant survey, extracts from progress notes, and audiotaped discussions about learnings from the program during the final session. RESULTS: Participants from both programs were highly satisfied and perceived improvements in everyday PM performance post-intervention. Elements that were highly valued include setting individualised client-centred goals, repetitive training of strategy use, establishing habits and routines, and receiving experiential, verbal, and written feedback.Changes including more therapy sessions were recommended. CONCLUSIONS: Both the COMP and COMP-MST programs were perceived as effective by participants with TBI in improving their PM performance in everyday life using compensatory strategies such as assistive technology. PRACTICE IMPLICATIONS: Routine collection of patient feedback on cognitive rehabilitation can provide valuable information to support person-centred implementation of clinical practice guidelines.


Assuntos
Lesões Encefálicas Traumáticas , Memória Episódica , Humanos , Lesões Encefálicas Traumáticas/psicologia , Lesões Encefálicas Traumáticas/reabilitação , Cognição , Aprendizagem , Transtornos da Memória , Resultado do Tratamento , Ensaios Clínicos como Assunto
17.
Sci Transl Med ; 16(742): eadk8222, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38598612

RESUMO

Despite modern antiseptic techniques, surgical site infection (SSI) remains a leading complication of surgery. However, the origins of SSI and the high rates of antimicrobial resistance observed in these infections are poorly understood. Using instrumented spine surgery as a model of clean (class I) skin incision, we prospectively sampled preoperative microbiomes and postoperative SSI isolates in a cohort of 204 patients. Combining multiple forms of genomic analysis, we correlated the identity, anatomic distribution, and antimicrobial resistance profiles of SSI pathogens with those of preoperative strains obtained from the patient skin microbiome. We found that 86% of SSIs, comprising a broad range of bacterial species, originated endogenously from preoperative strains, with no evidence of common source infection among a superset of 1610 patients. Most SSI isolates (59%) were resistant to the prophylactic antibiotic administered during surgery, and their resistance phenotypes correlated with the patient's preoperative resistome (P = 0.0002). These findings indicate the need for SSI prevention strategies tailored to the preoperative microbiome and resistome present in individual patients.


Assuntos
Anti-Infecciosos , Infecção da Ferida Cirúrgica , Humanos , Infecção da Ferida Cirúrgica/prevenção & controle , Infecção da Ferida Cirúrgica/tratamento farmacológico , Infecção da Ferida Cirúrgica/microbiologia , Antibioticoprofilaxia , Pele , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico
18.
iScience ; 27(4): 109576, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38638836

RESUMO

AML is characterized by mutations in genes associated with growth regulation such as internal tandem duplications (ITD) in the receptor kinase FLT3. Inhibitors targeting FLT3 (FLT3i) are being used to treat patients with FLT3-ITD+ but most relapse and become resistant. To elucidate the resistance mechanism, we compared the gene regulatory networks (GRNs) of leukemic cells from patients before and after relapse, which revealed that the GRNs of drug-responsive patients were altered by rewiring their AP-1-RUNX1 axis. Moreover, FLT3i induces the upregulation of signaling genes, and we show that multiple cytokines, including interleukin-3 (IL-3), can overcome FLT3 inhibition and send cells back into cycle. FLT3i leads to loss of AP-1 and RUNX1 chromatin binding, which is counteracted by IL-3. However, cytokine-mediated drug resistance can be overcome by a pan-RAS inhibitor. We show that cytokines instruct AML growth via the transcriptional regulators AP-1 and RUNX1 and that pan-RAS drugs bypass this barrier.

19.
BMC Prim Care ; 25(1): 153, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38711031

RESUMO

BACKGROUND: Clinical practice guidelines (CPGs) synthesize high-quality information to support evidence-based clinical practice. In primary care, numerous CPGs must be integrated to address the needs of patients with multiple risks and conditions. The BETTER program aims to improve prevention and screening for cancer and chronic disease in primary care by synthesizing CPGs into integrated, actionable recommendations. We describe the process used to harmonize high-quality cancer and chronic disease prevention and screening (CCDPS) CPGs to update the BETTER program. METHODS: A review of CPG databases, repositories, and grey literature was conducted to identify international and Canadian (national and provincial) CPGs for CCDPS in adults 40-69 years of age across 19 topic areas: cancers, cardiovascular disease, chronic obstructive pulmonary disease, diabetes, hepatitis C, obesity, osteoporosis, depression, and associated risk factors (i.e., diet, physical activity, alcohol, cannabis, drug, tobacco, and vaping/e-cigarette use). CPGs published in English between 2016 and 2021, applicable to adults, and containing CCDPS recommendations were included. Guideline quality was assessed using the Appraisal of Guidelines for Research and Evaluation (AGREE) II tool and a three-step process involving patients, health policy, content experts, primary care providers, and researchers was used to identify and synthesize recommendations. RESULTS: We identified 51 international and Canadian CPGs and 22 guidelines developed by provincial organizations that provided relevant CCDPS recommendations. Clinical recommendations were extracted and reviewed for inclusion using the following criteria: 1) pertinence to primary prevention and screening, 2) relevance to adults ages 40-69, and 3) applicability to diverse primary care settings. Recommendations were synthesized and integrated into the BETTER toolkit alongside resources to support shared decision-making and care paths for the BETTER program. CONCLUSIONS: Comprehensive care requires the ability to address a person's overall health. An approach to identify high-quality clinical guidance to comprehensively address CCDPS is described. The process used to synthesize and harmonize implementable clinical recommendations may be useful to others wanting to integrate evidence across broad content areas to provide comprehensive care. The BETTER toolkit provides resources that clearly and succinctly present a breadth of clinical evidence that providers can use to assist with implementing CCDPS guidance in primary care.


Assuntos
Guias de Prática Clínica como Assunto , Atenção Primária à Saúde , Prevenção Primária , Humanos , Atenção Primária à Saúde/normas , Prevenção Primária/normas , Canadá , Programas de Rastreamento/normas , Doença Crônica/prevenção & controle , Pessoa de Meia-Idade , Adulto , Idoso , Neoplasias/prevenção & controle , Neoplasias/diagnóstico
20.
Ecol Evol ; 14(6): e11341, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38826171

RESUMO

To address our climate emergency, "we must rapidly, radically reshape society"-Johnson & Wilkinson, All We Can Save. In science, reshaping requires formidable technical (cloud, coding, reproducibility) and cultural shifts (mindsets, hybrid collaboration, inclusion). We are a group of cross-government and academic scientists that are exploring better ways of working and not being too entrenched in our bureaucracies to do better science, support colleagues, and change the culture at our organizations. We share much-needed success stories and action for what we can all do to reshape science as part of the Open Science movement and 2023 Year of Open Science.

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