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1.
Stud Hist Philos Sci ; 97: 91-100, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36638558

RESUMO

The description of how individual models in families of models are related to each other is crucial for the general philosophical understanding of model-based scientific practice. We focus on the Capital Asset Pricing Models (CAPM) family, a cornerstone in financial economics, to provide a descriptive analysis of model relations within a family. We introduce the concepts of theoretical and empirical complementarity to characterise model relations. Our complementarity analysis of model relations has two types of payoff. Specifically regarding the CAPM, our analysis reveals why this model family, which has been empirically contested, has yet remained popular and important: the different models that have been added over time have made new empirically and theoretically complementary contributions to the model family. More generally, our analysis reveals the dynamic character of model-based scientific practice. Characterising relations between models as theoretically and/or empirically complementary yields three hitherto underappreciated lessons: (i) actual modelling purposes are not always primarily epistemic, (ii) a model's individual import is relative, not absolute, and (iii) there is an important interplay between theory and data models. Faithfully characterising scientific modelling in this way facilitates subsequent analysis of models' epistemic import.


Assuntos
Economia , Custos e Análise de Custo
2.
PLoS Med ; 18(5): e1003567, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34038421

RESUMO

BACKGROUND: Plasmodium vivax has been proposed to infect and replicate in the human spleen and bone marrow. Compared to Plasmodium falciparum, which is known to undergo microvascular tissue sequestration, little is known about the behavior of P. vivax outside of the circulating compartment. This may be due in part to difficulties in studying parasite location and activity in life. METHODS AND FINDINGS: To identify organ-specific changes during the early stages of P. vivax infection, we performed 18-F fluorodeoxyglucose (FDG) positron emission tomography/magnetic resonance imaging (PET/MRI) at baseline and just prior to onset of clinical illness in P. vivax experimentally induced blood-stage malaria (IBSM) and compared findings to P. falciparum IBSM. Seven healthy, malaria-naive participants were enrolled from 3 IBSM trials: NCT02867059, ACTRN12616000174482, and ACTRN12619001085167. Imaging took place between 2016 and 2019 at the Herston Imaging Research Facility, Australia. Postinoculation imaging was performed after a median of 9 days in both species (n = 3 P. vivax; n = 4 P. falciparum). All participants were aged between 19 and 23 years, and 6/7 were male. Splenic volume (P. vivax: +28.8% [confidence interval (CI) +10.3% to +57.3%], P. falciparum: +22.9 [CI -15.3% to +61.1%]) and radiotracer uptake (P. vivax: +15.5% [CI -0.7% to +31.7%], P. falciparum: +5.5% [CI +1.4% to +9.6%]) increased following infection with each species, but more so in P. vivax infection (volume: p = 0.72, radiotracer uptake: p = 0.036). There was no change in FDG uptake in the bone marrow (P. vivax: +4.6% [CI -15.9% to +25.0%], P. falciparum: +3.2% [CI -3.2% to +9.6%]) or liver (P. vivax: +6.2% [CI -8.7% to +21.1%], P. falciparum: -1.4% [CI -4.6% to +1.8%]) following infection with either species. In participants with P. vivax, hemoglobin, hematocrit, and platelet count decreased from baseline at the time of postinoculation imaging. Decrements in hemoglobin and hematocrit were significantly greater in participants with P. vivax infection compared to P. falciparum. The main limitations of this study are the small sample size and the inability of this tracer to differentiate between host and parasite metabolic activity. CONCLUSIONS: PET/MRI indicated greater splenic tropism and metabolic activity in early P. vivax infection compared to P. falciparum, supporting the hypothesis of splenic accumulation of P. vivax very early in infection. The absence of uptake in the bone marrow and liver suggests that, at least in early infection, these tissues do not harbor a large parasite biomass or do not provoke a prominent metabolic response. PET/MRI is a safe and noninvasive method to evaluate infection-associated organ changes in morphology and glucose metabolism.


Assuntos
Medula Óssea/parasitologia , Glucose/metabolismo , Fígado/parasitologia , Malária Falciparum/parasitologia , Malária Vivax/parasitologia , Baço/parasitologia , Medula Óssea/metabolismo , Medula Óssea/patologia , Feminino , Humanos , Fígado/metabolismo , Fígado/patologia , Imageamento por Ressonância Magnética , Malária Falciparum/patologia , Malária Falciparum/fisiopatologia , Malária Vivax/patologia , Malária Vivax/fisiopatologia , Masculino , Plasmodium falciparum , Plasmodium vivax , Tomografia por Emissão de Pósitrons , Estudos Prospectivos , Queensland , Coluna Vertebral/metabolismo , Coluna Vertebral/parasitologia , Coluna Vertebral/patologia , Baço/metabolismo , Baço/patologia , Adulto Jovem
3.
J Virol ; 94(23)2020 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-32938764

RESUMO

HIV-1 encodes an envelope glycoprotein (Env) that contains a long cytoplasmic tail (CT) harboring trafficking motifs implicated in Env incorporation into virus particles and viral transmission. In most physiologically relevant cell types, the gp41 CT is required for HIV-1 replication, but in the MT-4 T-cell line the gp41 CT is not required for a spreading infection. To help elucidate the role of the gp41 CT in HIV-1 transmission, in this study, we investigated the viral and cellular factors that contribute to the permissivity of MT-4 cells to gp41 CT truncation. We found that the kinetics of HIV-1 production and virus release are faster in MT-4 than in the other T-cell lines tested, but MT-4 cells express equivalent amounts of HIV-1 proteins on a per-cell basis relative to cells not permissive to CT truncation. MT-4 cells express higher levels of plasma-membrane-associated Env than nonpermissive cells, and Env internalization from the plasma membrane is less efficient than that from another T-cell line, SupT1. Paradoxically, despite the high levels of Env on the surface of MT-4 cells, 2-fold less Env is incorporated into virus particles produced from MT-4 than SupT1 cells. Contact-dependent transmission between cocultured 293T and MT-4 cells is higher than in cocultures of 293T with most other T-cell lines tested, indicating that MT-4 cells are highly susceptible to cell-to-cell infection. These data help to clarify the long-standing question of how MT-4 cells overcome the requirement for the HIV-1 gp41 CT and support a role for gp41 CT-dependent trafficking in Env incorporation and cell-to-cell transmission in physiologically relevant cell lines.IMPORTANCE The HIV-1 Env cytoplasmic tail (CT) is required for efficient Env incorporation into nascent particles and viral transmission in primary CD4+ T cells. The MT-4 T-cell line has been reported to support multiple rounds of infection of HIV-1 encoding a gp41 CT truncation. Uncovering the underlying mechanism of MT-4 T-cell line permissivity to gp41 CT truncation would provide key insights into the role of the gp41 CT in HIV-1 transmission. This study reveals that multiple factors contribute to the unique ability of a gp41 CT truncation mutant to spread in cultures of MT-4 cells. The lack of a requirement for the gp41 CT in MT-4 cells is associated with the combined effects of rapid HIV-1 protein production, high levels of cell-surface Env expression, and increased susceptibility to cell-to-cell transmission compared to nonpermissive cells.


Assuntos
Proteína gp41 do Envelope de HIV/genética , Proteína gp41 do Envelope de HIV/metabolismo , HIV-1/fisiologia , Linhagem Celular , Membrana Celular/metabolismo , Expressão Gênica , Células HEK293 , Humanos , Masculino , Transporte Proteico , Linfócitos T/virologia , Vírion/metabolismo , Replicação Viral
4.
Malar J ; 20(1): 93, 2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33593375

RESUMO

BACKGROUND: New anti-malarial therapeutics are required to counter the threat of increasing drug resistance. Malaria volunteer infection studies (VIS), particularly the induced blood stage malaria (IBSM) model, play a key role in accelerating anti-malarial drug development. Supply of the reference 3D7-V2 Plasmodium falciparum malaria cell bank (MCB) is limited. This study aimed to develop a new MCB, and compare the safety and infectivity of this MCB with the existing 3D7-V2 MCB, in a VIS. A second bank (3D7-V1) developed in 1995 was also evaluated. METHODS: The 3D7-V2 MCB was expanded in vitro using a bioreactor to produce a new MCB designated 3D7-MBE-008. This bank and 3D7-V1 were then evaluated using the IBSM model, where healthy participants were intravenously inoculated with blood-stage parasites. Participants were treated with artemether-lumefantrine when parasitaemia or clinical thresholds were reached. Safety, infectivity and parasite growth and clearance were evaluated. RESULTS: The in vitro expansion of 3D7-V2 produced 200 vials of the 3D7-MBE-008 MCB, with a parasitaemia of 4.3%. This compares to 0.1% in the existing 3D7-V2 MCB, and < 0.01% in the 3D7-V1 MCB. All four participants (two per MCB) developed detectable P. falciparum infection after inoculation with approximately 2800 parasites. For the 3D7-MBE-008 MCB, the parasite multiplication rate of 48 h (PMR48) using non-linear mixed effects modelling was 34.6 (95% CI 18.5-64.6), similar to the parental 3D7-V2 line; parasitaemia in both participants exceeded 10,000/mL by day 8. Growth of the 3D7-V1 was slower (PMR48 of 11.5 [95% CI 8.5-15.6]), with parasitaemia exceeding 10,000 parasites/mL on days 10 and 8.5. Rapid parasite clearance followed artemether-lumefantrine treatment in all four participants, with clearance half-lives of 4.01 and 4.06 (weighted mean 4.04 [95% CI 3.61-4.57]) hours for 3D7-MBE-008 and 4.11 and 4.52 (weighted mean 4.31 [95% CI 4.16-4.47]) hours for 3D7-V1. A total of 59 adverse events occurred; most were of mild severity with three being severe in the 3D7-MBE-008 study. CONCLUSION: The safety, growth and clearance profiles of the expanded 3D7-MBE-008 MCB closely resemble that of its parent, indicating its suitability for future studies. TRIAL REGISTRATION: Australian New Zealand Clinical Trials registry numbers: P3487 (3D7-V1): ACTRN12619001085167. P3491 (3D7-MBE-008): ACTRN12619001079134.


Assuntos
Antimaláricos/uso terapêutico , Bancos de Espécimes Biológicos , Ensaios Clínicos como Assunto , Voluntários Saudáveis/estatística & dados numéricos , Malária Falciparum/tratamento farmacológico , Plasmodium falciparum
5.
J Biol Chem ; 294(44): 16266-16281, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31519756

RESUMO

The endosomal sorting complexes required for transport (ESCRT) machinery drives membrane scission for diverse cellular functions that require budding away from the cytosol, including cell division and transmembrane receptor trafficking and degradation. The ESCRT machinery is also hijacked by retroviruses, such as HIV-1, to release virions from infected cells. The crucial roles of the ESCRTs in cellular physiology and viral disease make it imperative to understand the membrane scission mechanism. Current methodological limitations, namely artifacts caused by overexpression of ESCRT subunits, obstruct our understanding of the spatiotemporal organization of the endogenous human ESCRT machinery. Here, we used CRISPR/Cas9-mediated knock-in to tag the critical ESCRT-I component tumor susceptibility 101 (Tsg101) with GFP at its native locus in two widely used human cell types, HeLa epithelial cells and Jurkat T cells. We validated this approach by assessing the function of these knock-in cell lines in cytokinesis, receptor degradation, and virus budding. Using this probe, we measured the incorporation of endogenous Tsg101 in released HIV-1 particles, supporting the notion that the ESCRT machinery initiates virus abscission by scaffolding early-acting ESCRT-I within the head of the budding virus. We anticipate that these validated cell lines will be a valuable tool for interrogating dynamics of the native human ESCRT machinery.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Fatores de Transcrição/metabolismo , Sistemas CRISPR-Cas , Citocinese/fisiologia , Proteínas de Ligação a DNA/genética , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Genômica/métodos , HIV-1/metabolismo , Células HeLa , Humanos , Células Jurkat , Transporte Proteico , Fatores de Transcrição/genética , Vírion/metabolismo , Liberação de Vírus
6.
J Virol ; 93(24)2019 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-31554688

RESUMO

The MT-4 human T-cell line expresses HTLV-1 Tax and is permissive for replication of an HIV-1 gp41 mutant lacking the cytoplasmic tail. MT-4 cells (lot 150048), distributed by the NIH AIDS Reagent Program (NIH-ARP), were found to be Tax deficient and unable to host replication of the gp41-truncated HIV-1 mutant. These findings, together with short tandem repeat profiling, established that lot 150048 are not bona fide MT-4 cells.


Assuntos
Síndrome da Imunodeficiência Adquirida , Linhagem Celular/virologia , Linfócitos T/virologia , Produtos do Gene tax/genética , Proteína gp41 do Envelope de HIV/genética , HIV-1/genética , Vírus Linfotrópico T Tipo 1 Humano , Humanos , Repetições de Microssatélites , National Institutes of Health (U.S.) , Estados Unidos , Replicação Viral
7.
Can J Diet Pract Res ; 81(2): 86-90, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-31736382

RESUMO

This study aimed to measure the influence of the Chefs in Action program (3 cooking workshops) on cooking skills, nutrition knowledge, and attitudes towards healthy eating in children attending summer day camps and compare it with a single cooking workshop. Groups of children (8-12 years) were randomly assigned to the intervention group (n = 25) or to 1 of 3 comparison groups performing a single workshop (group 1, n = 16; group 2, n = 36; group 3, n = 24). Two dietitians evaluated cooking skills during the workshops. Nutrition knowledge and attitudes towards healthy eating were assessed before and after the intervention. No improvement in cooking skills was observed in the intervention group (P = 0.25). The intervention group's cooking skills score was significantly higher than comparison group 1 (P < 0.001). Nutrition knowledge was significantly improved in the intervention group and the comparison group 3 (P < 0.0001) but no effect on attitudes towards healthy eating was observed (Pgroup × time = 0.36). In conclusion, the Chefs in Action program positively impacted nutrition knowledge in children. The results also suggest that the type of recipe may influence nutrition knowledge and cooking skills. Further studies are needed to better assess the degree of difficulty required in cooking workshop recipes to improve cooking skills in children.


Assuntos
Culinária/métodos , Dieta Saudável/métodos , Educação em Saúde/métodos , Conhecimentos, Atitudes e Prática em Saúde , Criança , Feminino , Humanos , Masculino , Ciências da Nutrição/educação , Nutricionistas , Quebeque
8.
Public Health Nutr ; 22(18): 3349-3359, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31663493

RESUMO

OBJECTIVE: To evaluate awareness of the Eat Well Campaign (EWC) among parents and assess perceptions about its effectiveness. DESIGN: Post-campaign evaluation study with a cross-section of parents recruited through random digit dialling. Participants completed an online survey about EWC awareness, its perceived effectiveness among parents and their meal planning practices (attitudes, behaviours and self-efficacy). SETTING: A federal mass-media campaign disseminated by Health Canada (2013-2014) to promote meal planning to Canadian parents. PARTICIPANTS: Parents (n 964) of children aged 2-12 years from all Provinces and Territories. RESULTS: Of respondents, 41 % (390/964) were aware of the campaign; Quebec City and rural Quebec had the highest rates of awareness, whereas Vancouver, Winnipeg and Toronto had the lowest. Awareness was greater among parents with lower income, basic education and French-speakers. Campaign intensity was significantly associated with greater odds of reporting positive attitudes towards the EWC and meal planning (P < 0·05). Campaign awareness was significantly associated with greater odds of believing that meal planning helps maintain a healthy diet (OR = 1·68, 95 % CI 1·03, 2·74) and planning meals (OR = 1·66, 95 % CI 1·03, 2·54), but not self-efficacy, in adjusted models. CONCLUSIONS: The present study is the first to evaluate an initiative that promoted meal planning with mass media. The EWC demonstrated evidence of success in terms of equitable access to a nutrition initiative by reaching lower-income and less-educated parents. Understanding behavioural factors among different segments of the population will be important to target appropriate audiences and develop tailored interventions that support healthy eating practices.


Assuntos
Dieta Saudável/métodos , Promoção da Saúde/métodos , Meios de Comunicação de Massa , Refeições/fisiologia , Pais/psicologia , Adulto , Canadá , Estudos Transversais , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade
9.
BMC Public Health ; 19(1): 672, 2019 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31151393

RESUMO

BACKGROUND: There has been an increasing interest in urban agriculture (UA) practice and research in recent years. Scholars have already reported numerous beneficial and potential adverse impacts of UA on health-related outcomes. This scoping review aims to explore these impacts and identify knowledge gaps for future UA studies. METHODS: A systematic search was conducted in seven electronic bibliographic databases to identify relevant peer-reviewed studies. Articles were screened and assessed for eligibility. From eligible studies, data were extracted to summarize, collate, appraise the quality and make a narrative account of the findings. RESULTS: A total of 101 articles (51 quantitative, 29 qualitative, and 21 mixed methods studies) were included in our final analysis. Among these articles, 38 and 37% reported findings from North America and Sub-Saharan Africa respectively. Quantitative studies revealed evidence of positive impacts of UA on food security, nutrition outcomes, physical and mental health outcomes, and social capital. The qualitative studies reported a wide range of perceived benefits and motivations of UA. The most frequently reported benefits include contributions to social capital, food security, health and/or wellbeing. However, the evidence must be interpreted with caution since the quality of most of the studies was assessed as weak to moderate. While no definitive conclusions can be drawn about the adverse impacts of UA on health, paying particular attention to contamination of UA soil is recommended. CONCLUSION: More peer-reviewed studies are needed in areas where UA is practiced such as Latin America and Caribbean. The inconsistency and the lack of strong quality in the methodology of the included studies are proof that more rigorous studies are also needed in future research. Nevertheless, the substantial existing evidence from this review corroborate that UA can influence different determinants of health such as food security, social capital, health and well-being in a variety of contexts.


Assuntos
Agricultura , Determinantes Sociais da Saúde , Saúde da População Urbana/estatística & dados numéricos , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
Can J Diet Pract Res ; 80(2): 63-71, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30724091

RESUMO

Purpose: To explore the associations between full-time employment status, food skills, and diet quality of Canadian parents. Methods: A sample of Canadian parents (n = 767) were invited to complete a web-based survey that included sociodemographic variables, questions about food skills, and a validated food frequency questionnaire. Results were analyzed with linear and logistic regression models, controlling for sociodemographic variables and multiple testing. Results: After controlling for covariates and multiple testing, there were no statistically significant differences in foods skills between parents' employment status. Time was the most reported barrier for meal preparation, regardless of work status, but was significantly greater for full-time compared with other employment status (P < 0.0001). Additionally, parents who worked full-time had lower odds of reporting food preferences or dietary restrictions (P = 0.0001) and health issues or allergies (P = 0.0003) as barriers to food preparation, compared with parents with other employment status. These results remained statistically significant even after controlling for covariates and multiple testing. Conclusions: Overall, food skills did not differ significantly between parents' employment status. Time, however, was an important barrier for most parents, especially those working full time. To promote home-based food preparation among parents, strategies to manage time scarcity are needed.


Assuntos
Culinária/estatística & dados numéricos , Dieta Saudável/estatística & dados numéricos , Emprego/estatística & dados numéricos , Pais , Adulto , Canadá , Registros de Dieta , Hipersensibilidade Alimentar , Preferências Alimentares , Humanos , Masculino , Refeições , Fatores Socioeconômicos , Inquéritos e Questionários , Fatores de Tempo
11.
Public Health Nutr ; 20(13): 2318-2328, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28633687

RESUMO

OBJECTIVE: To identify facilitators and barriers that Health Canada's (HC) cross-sector partners experienced while implementing the Eat Well Campaign: Food Skills (EWC; 2013-2014) and describe how these experiences might differ according to distinct partner types. DESIGN: A qualitative study using hour-long semi-structured telephone interviews conducted with HC partners that were transcribed verbatim. Facilitators and barriers were identified inductively and analysed according partner types. SETTING: Implementation of a national mass-media health education campaign. SUBJECTS: Twenty-one of HC's cross-sector partners (food retailers, media and health organizations) engaged in the EWC. RESULTS: Facilitators and barriers were grouped into seven major themes: operational elements, intervention factors, resources, collaborator traits, developer traits, partnership factors and target population factors. Four of these themes had dual roles as both facilitators and barriers (intervention factors, resources, collaborator traits and developer traits). Sub-themes identified as both facilitators and barriers illustrate the extent to which a facilitator can easily become a barrier. Partnership factors were unique facilitators, while operational and target population factors were unique barriers. Time was a barrier that was common to almost all partners regardless of partnership type. There appeared to be a greater degree of uniformity among facilitators, whereas barriers were more diverse and unique to the realities of specific types of partner. CONCLUSIONS: Collaborative planning will help public health organizations anticipate barriers unique to the realities of specific types of organizations. It will also prevent facilitators from becoming barriers. Advanced planning will help organizations manage time constraints and integrate activities, facilitating implementation.


Assuntos
Dieta Saudável , Implementação de Plano de Saúde , Promoção da Saúde , Colaboração Intersetorial , Meios de Comunicação de Massa , Obesidade Infantil/prevenção & controle , Parcerias Público-Privadas , Canadá , Criança , Fenômenos Fisiológicos da Nutrição Infantil , Barreiras de Comunicação , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Pais/educação , Cooperação do Paciente , Pesquisa Qualitativa , Recursos Humanos
12.
BMC Public Health ; 16: 904, 2016 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-27578205

RESUMO

BACKGROUND: The Eat Well Campaign (EWC) was a social marketing campaign developed by Health Canada and disseminated to the public with the help of cross-sector partners. The purpose of this study was to describe factors that influenced cross-sector partners' decision to adopt the EWC. METHODS: Thematic content analysis, based primarily on an a priori codebook of constructs from Roger's diffusion of innovations decision process model, was conducted on hour-long semi-structured telephone interviews with Health Canada's cross-sector partners (n = 18). RESULTS: Dominant themes influencing cross-sector partners' decision to adopt the EWC were: high compatibility with the organization's values; being associated with Health Canada; and low perceived complexity of activities. Several adopters indicated that social norms (e.g., knowing that other organizations in their network were involved in the collaboration) played a strong role in their decision to participate, particularly for food retailers and small organizations. The opportunity itself to work in partnership with Health Canada and other organizations was seen as a prominent relative advantage by many organizations. Adopters were characterized as having high social participation and positive attitudes towards health, new ideas and Health Canada. The lack of exposure to the mass media channels used to diffuse the campaign and reserved attitudes towards Health Canada were prominent obstacles identified by a minority of health organizations, which challenged the decision to adopt the EWC. Most other barriers were considered as minor challenges and did not appear to impede the adoption process. CONCLUSIONS: Understanding factors that influence cross-sector adoption of nutrition initiatives can help decision makers target the most appropriate partners to advance public health objectives. Government health agencies are likely to find strong partners in organizations that share the same values as the initiative, have positive attitudes towards health, are extremely implicated in social causes and value the notion of partnership.


Assuntos
Atitude , Comportamento Cooperativo , Dieta Saudável , Órgãos Governamentais , Promoção da Saúde/métodos , Organizações , Parcerias Público-Privadas , Canadá , Humanos , Obesidade/prevenção & controle , Setor Privado , Saúde Pública , Setor Público , Pesquisa Qualitativa , Marketing Social
13.
Public Health Nutr ; 18(17): 3070-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26228380

RESUMO

OBJECTIVE: To examine overweight and obesity (OWOB), changes in prevalence and potential risk factors in Barbadian children. DESIGN: A cross-section of students were weighed and measured. The WHO BMI-for-age growth references (BAZ), the International Obesity Task Force cut-offs and the US Centers for Disease Control and Prevention growth percentiles were used to determine OWOB prevalence. Harvard weight-for-height-for-age growth standards were used to estimate differences in OWOB prevalence from 1981 to 2010. Samples of parents and students were interviewed to describe correlates of OWOB. SETTING: Barbados. SUBJECTS: Public-school students (n 580) in class 3. RESULTS: Based on WHO BAZ, the overall prevalence of OWOB was 34·8 % (95 % CI 30·9, 38·7 %). A trend of higher OWOB prevalence was seen for girls across cut-offs, with significant sex differences noted using the International Obesity Task Force cut-offs. According to Harvard growth standards, OWOB has increased dramatically, from 8·52 % to 32·5 %. Children were more likely to be OWOB when annual household income was below BBD 9000 (OR=2·69; 95 % CI 1·21, 5·99). Eating dinner with the family every night was associated with a lower prevalence of OWOB (OR=0·56; 95 % CI 0·36, 0·87). CONCLUSIONS: The sharp increase of OWOB rates in Barbados warrants attention. Sex disparities in OWOB prevalence may emerge at a young age. Promoting family meals may be a feasible option for OWOB prevention. Understanding familial and sociodemographic factors influencing OWOB will be useful in planning successful intervention or prevention programmes in Barbados.


Assuntos
Fenômenos Fisiológicos da Nutrição Infantil , Transição Epidemiológica , Estado Nutricional , Sobrepeso/epidemiologia , Obesidade Infantil/epidemiologia , Atividades Cotidianas , Barbados/epidemiologia , Índice de Massa Corporal , Criança , Estudos Transversais , Família , Feminino , Humanos , Masculino , Refeições , Inquéritos Nutricionais , Sobrepeso/diagnóstico , Sobrepeso/prevenção & controle , Obesidade Infantil/diagnóstico , Obesidade Infantil/prevenção & controle , Pobreza , Guias de Prática Clínica como Assunto , Prevalência , Fatores de Risco , Instituições Acadêmicas , Fatores Sexuais
14.
Proc Natl Acad Sci U S A ; 109(35): 14122-7, 2012 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-22879398

RESUMO

HIV modulates plasmacytoid dendritic cell (pDC) activation via Toll-like receptor 7, inducing type I IFN and inflammatory cytokines. Simultaneously, pDCs up-regulate the expression of indoleamine 2,3 dioxygenase (IDO), which is essential for the induction of regulatory T cells (Tregs), which function to down-modulate immune activation. Here we demonstrate the crucial importance of the noncanonical NF-κB pathway in the establishment of this immunoregulatory phenotype in pDCs. In response to HIV, the noncanonical NF-κB pathway directly induces IDO and involves the recruitment of TNF receptor-associated factor-3 to the Toll-like receptor/MyD88 complex, NF-κB-inducing kinase-dependent IκB kinase-α activation, and p52/RelB nuclear translocation. We also show that pDC-induced Tregs can inhibit conventional DC (cDC) maturation partially through cytotoxic T-lymphocyte antigen (CTLA)-4 engagement. Furthermore, CTLA-4 induces IDO in cDCs in a NF-κB-inducing kinase-dependent way. These CTLA-4-conditioned cDCs can in turn induce Treg differentiation in an IDO-dependent manner. Thus, the noncanonical NF-κB pathway is integral in controlling immunoregulatory phenotypes of both pDCs and cDCs.


Assuntos
Células Dendríticas/imunologia , Células Dendríticas/virologia , Infecções por HIV/imunologia , Subunidade p52 de NF-kappa B/imunologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/virologia , Expressão Gênica/imunologia , Técnicas de Silenciamento de Genes , Infecções por HIV/metabolismo , Humanos , Quinase I-kappa B/genética , Quinase I-kappa B/imunologia , Quinase I-kappa B/metabolismo , Imunofenotipagem , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Indolamina-Pirrol 2,3,-Dioxigenase/imunologia , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Fator 88 de Diferenciação Mieloide/imunologia , Fator 88 de Diferenciação Mieloide/metabolismo , Subunidade p52 de NF-kappa B/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/imunologia , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais/imunologia , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/virologia , Fator 3 Associado a Receptor de TNF/imunologia , Fator 3 Associado a Receptor de TNF/metabolismo , Quinase Induzida por NF-kappaB
15.
Curr Rheumatol Rep ; 16(2): 396, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24357442

RESUMO

Chronic wounds are an important health problem because they are difficult to heal and treatment is often complicated, lengthy and expensive. For a majority of sufferers the most common outcomes are long-term immobility, infection and prolonged hospitalisation. There is therefore an urgent need for effective therapeutics that will enhance ulcer healing and patient quality of life, and will reduce healthcare costs. Studies in our laboratory have revealed elevated levels of purine catabolites in wound fluid from patients with venous leg ulcers. In particular, we have discovered that uric acid is elevated in wound fluid, with higher concentrations correlating with increased wound severity. We have also revealed a corresponding depletion in uric acid precursors, including adenosine. Further, we have revealed that xanthine oxidoreductase, the enzyme that catalyses the production of uric acid, is present at elevated levels in wound fluid. Taken together, these findings provide evidence that xanthine oxidoreductase may have a function in the formation or persistence of chronic wounds. Here we describe the potential function of xanthine oxidoreductase and uric acid accumulation in the wound site, and the effect of xanthine oxidoreductase in potentiating the inflammatory response.


Assuntos
Ácido Úrico/metabolismo , Úlcera Varicosa/fisiopatologia , Cicatrização/fisiologia , Xantina Desidrogenase/fisiologia , Alopurinol/uso terapêutico , Doença Crônica , Inibidores Enzimáticos/uso terapêutico , Sequestradores de Radicais Livres/uso terapêutico , Radicais Livres/metabolismo , Humanos , Inflamação/fisiopatologia , Úlcera Varicosa/tratamento farmacológico , Cicatrização/efeitos dos fármacos , Xantina Desidrogenase/antagonistas & inibidores
16.
BMJ Open ; 14(3): e079685, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38531579

RESUMO

INTRODUCTION: Multimodal pain control following cardiothoracic surgery remains a focus in international guidelines. We hypothesise that non-depolarising skeletal muscle relaxants can prove to be a useful adjunct for this population. METHODS/ANALYSIS: This systematic review will focus on human adult studies of pain control using muscle relaxants within 1 week following cardiac and thoracic surgery available in PubMed, Cochrane Central, Web of Science and EMBASE. Target studies will have a primary focus on measured effects on quality of pain control and reduction in opioid usage. Studies that include non-depolarising skeletal muscle relaxants given during cardiothoracic surgery or in the week after will be included. Study selection will be in keeping with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Procedures and agents used will be analysed together, and a meta-analysis will be conducted then compared with current therapies recommended in international practice guidelines. ETHICS AND DISSEMINATION: Formal ethical approval will not be required as primary data will not be collected. The results will be disseminated through peer-reviewed publication, conference presentation and lay press. PROSPERO REGISTRATION NUMBER: CRD42023397917.


Assuntos
Fármacos Neuromusculares , Manejo da Dor , Adulto , Humanos , Revisões Sistemáticas como Assunto , Dor , Projetos de Pesquisa , Metanálise como Assunto
17.
Appl Physiol Nutr Metab ; 49(3): 330-339, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37931241

RESUMO

To improve health outcomes, home cooking has been suggested as a solution to reduce intakes of processed foods. However, little is known about how cooking skills or cooking with processed foods influence health. This cross-sectional study examined associations between diet and health outcomes with cooking skills and cooking with processed foods. The dataset included a nationally representative sample of 18 460 adults from Canadian Community Health Survey (CCHS) annual component rapid response modules on food skills. In the CCHS rapid response modules, diet and health outcomes (fruit and vegetable intake, general health, mental health, and obesity) and data related to cooking skills and cooking with processed foods were collected through self-report. Separate logistic regression models were fitted for each outcome, controlling for age, income, and education, and stratified by sex. Adults with poor cooking skills were less likely to have adequate fruit and vegetable intake (≥5 servings per day) (p < 0.001), very good general health (p < 0.001) or mental health (p < 0.001), and obesity (p = 0.02) compared to advanced cooking skills. Adults who cooked with highly processed foods were less likely to have adequate fruit and vegetable intake (p < 0.001), very good general health (p = 0.002) or mental health (p < 0.001), but more likely to have obesity (p = 0.03) compared to cooking with minimally processed foods. Cooking skills alone appear insufficient to protect against obesity. Results suggest that not only are cooking skills important, but the quality of ingredients also matter. Limiting the use of processed foods in addition to improving cooking skills are potential intervention targets to promote better health and diet outcomes.


Assuntos
Culinária , Alimento Processado , Adulto , Humanos , Estudos Transversais , Canadá , Frutas , Obesidade/epidemiologia , Autorrelato
18.
Mar Environ Res ; 193: 106288, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38043169

RESUMO

At the regional scale, upwelling conditions are known to influence ecosystems and communities and their primary and secondary productivity. However, the influence of upwelling on local herbivore-algae interactions is less well understood. We address this question by cross-examining herbivores and seaweeds from sites associated with upwelling and downwelling conditions along the Humboldt Current System. Specifically, we quantified the feeding and benefits attained by the black sea urchin (Tetrapygus niger) and the black sea snail (Tegula atra) while consuming a widespread kelp species (Lessonia spicata). We hypothesized that food quality drives herbivores' preference, consumption, and growth rates, regardless of the origin or "prior" conditions of the consumers. Laboratory trials measured algal consumption rates with (preference) and without a choice, and consumer's growth rates, to assess the influence of food quality (algae from upwelling vs downwelling sites) and the site of origin of the consumers. Our results showed that algal quality was a prevailing factor for both herbivores: they chose, consumed more, and grew faster on high quality (upwelling) algae. By comparison, the origin of the consumer was only significant for sea snails: those coming from an upwelling site, consumed significantly more and grew faster than those from downwelling. The bulk of our results provided strong support to our hypothesis and suggest that the high nutritional quality of algae associated with upwelling centers has a strong influence on consumers' preferences, consumption, and performance (growth). The fact that origin was found to be relevant for one of the herbivores suggests that the conditions in which species grow may dictate some of their efficiency as consumers.


Assuntos
Herbivoria , Alga Marinha , Ecossistema , Comportamento Alimentar
19.
Obes Rev ; 25(6): e13720, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38346847

RESUMO

Food accessibility was considerably impacted by restrictions during the coronavirus disease 2019 (COVID-19) pandemic, leading to growth in the online food retail sector, which offered contact-free delivery. This systematic review aimed to assess the change in use of online food retail platforms during COVID-19. The secondary aim was to identify diet-related chronic disease risk factors including dietary intake, eating behaviors, and/or weight status associated with the use of online food retail platforms during the pandemic. The review was registered in the International Prospective Register of Systematic Reviews (PROSPERO) (CRD42022320498) and adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Nine electronic databases were searched between January 2020 and October 2023. Studies that reported the frequency or change in use of online groceries, meal delivery applications, and/or meal-kit delivery services before and during the pandemic were included. A total of 53 studies were identified, including 46 cross-sectional studies, 4 qualitative studies, 2 longitudinal cohort studies, and 1 mixed-methods study. Overall, 96% (43/45) of outcomes showed an increase in the use of online groceries during COVID-19, while 55% (22/40) of outcomes showed a decrease in meal delivery applications. Eight of nine outcomes associated the use of online food retail with weight gain and emotional eating. Further research is needed to investigate the links between online food retail and obesity.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Fatores de Risco , Doença Crônica/epidemiologia , SARS-CoV-2 , Comportamento Alimentar , Dieta , Abastecimento de Alimentos , Internet , Pandemias , Comércio , Obesidade/epidemiologia
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