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1.
Behav Brain Sci ; 46: e209, 2023 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-37694989

RESUMO

"Challenging the utility of polygenic scores for social science" is a compelling but limited critique. Phenotypic development is sensitive to both initial conditions and all subsequent states - from conception to senescence. Thus, gene-centric analyses are misleading (and often meaningless) because gene products are transformed, and their phenotypic 'effects' combined and attenuated with successive propagations from molecular and cellular contexts to organismal and social environments.


Assuntos
Reprodução , Meio Social , Humanos , Ciências Sociais
2.
Crit Rev Food Sci Nutr ; 61(22): 3725-3739, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32799555

RESUMO

Sugar, tobacco, and alcohol have been demonized since the seventeenth century. Yet unlike tobacco and alcohol, there is indisputable scientific evidence that dietary sugars were essential for human evolution and are essential for human health and development. Therefore, the purpose of this analytic review and commentary is to demonstrate that anti-sugar rhetoric is divorced from established scientific facts and has led to politically expedient but ill-informed policies reminiscent of those enacted about alcohol a century ago in the United States. Herein, we present a large body of interdisciplinary research to illuminate several misconceptions, falsehoods, and facts about dietary sugars. We argue that anti-sugar policies and recommendations are not merely unscientific but are regressive and unjust because they harm the most vulnerable members of our society while providing no personal or public health benefits.


Assuntos
Açúcares da Dieta , Políticas , Humanos , Açúcares , Estados Unidos
3.
Crit Rev Food Sci Nutr ; 61(4): 622-635, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32308009

RESUMO

Objective: To examine the relation between the consumption or avoidance of meat and psychological health and well-being.Methods: A systematic search of online databases (PubMed, PsycINFO, CINAHL Plus, Medline, and Cochrane Library) was conducted for primary research examining psychological health in meat-consumers and meat-abstainers. Inclusion criteria were the provision of a clear distinction between meat-consumers and meat-abstainers, and data on factors related to psychological health. Studies examining meat consumption as a continuous or multi-level variable were excluded. Summary data were compiled, and qualitative analyses of methodologic rigor were conducted. The main outcome was the disparity in the prevalence of depression, anxiety, and related conditions in meat-consumers versus meat-abstainers. Secondary outcomes included mood and self-harm behaviors.Results: Eighteen studies met the inclusion/exclusion criteria; representing 160,257 participants (85,843 females and 73,232 males) with 149,559 meat-consumers and 8584 meat-abstainers (11 to 96 years) from multiple geographic regions. Analysis of methodologic rigor revealed that the studies ranged from low to severe risk of bias with high to very low confidence in results. Eleven of the 18 studies demonstrated that meat-abstention was associated with poorer psychological health, four studies were equivocal, and three showed that meat-abstainers had better outcomes. The most rigorous studies demonstrated that the prevalence or risk of depression and/or anxiety were significantly greater in participants who avoided meat consumption.Conclusion: Studies examining the relation between the consumption or avoidance of meat and psychological health varied substantially in methodologic rigor, validity of interpretation, and confidence in results. The majority of studies, and especially the higher quality studies, showed that those who avoided meat consumption had significantly higher rates or risk of depression, anxiety, and/or self-harm behaviors. There was mixed evidence for temporal relations, but study designs and a lack of rigor precluded inferences of causal relations. Our study does not support meat avoidance as a strategy to benefit psychological health.


Assuntos
Depressão , Dieta Vegetariana , Carne , Saúde Mental , Ansiedade , Depressão/epidemiologia , Feminino , Humanos , Masculino
4.
Arch Environ Contam Toxicol ; 80(4): 717-725, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32948887

RESUMO

Thyroid hormones play critical roles in body growth and development as well as reproduction. They also influence the activities of a wider variety of tissues and biological functions, such as osmoregulation, metabolism, and especially metamorphosis in organisms, such as frogs. These complex activities of thyroid hormones are prone to disruption by agricultural pesticides, often leading to modulation of growth and the reproductive system in particular. These substances include Glufosinate ammonium, Glyphosates, Imazapyr, Penoxsulam, and Diquat dibromide among other herbicides. In this study, the standardized Xenopus Metamorphosis Assay protocol was used to assess the potential thyroid-modulatory properties of the Glufosinate ammonium Basta formulation, at relevant environmental concentrations (0.05 mg/L, 0.15 mg/L, and 0.25 mg/L) for 21 days. The results showed that this formulation only reduced the hind-limb length among the morphological endpoints. Histological evaluation showed that the mean thyroid gland area and the mean thyroidal follicle epithelium height were significantly increased following 0.15 and 0.25 mg/L exposures. The present study confirmed that this Basta formulation interacts with the thyroid axis and therefore potentially pose health hazard to amphibian in particular and potentially metamorphic aquatic vertebrates. Furthermore, the result is a signal of inherent potential thyroid disrupting activities that must be further investigated and characterised in some of the aquatic herbicide formulations to safeguard the aquatic biodiversity.


Assuntos
Herbicidas , Glândula Tireoide , Aminobutiratos , Animais , Herbicidas/toxicidade , Larva , Metamorfose Biológica , Xenopus laevis
5.
Lancet ; 394(10194): 214-215, 2019 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-31235283
6.
J Health Commun ; 20(9): 1041-51, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25996371

RESUMO

This study examined the effects of text message content (generic vs. culturally tailored) on the login rate of an Internet physical activity program in Hong Kong Chinese adolescent school children. A convenience sample of 252 Hong Kong secondary school adolescents (51% female, 49% male; M age = 13.17 years, SD = 1.28 years) were assigned to one of 3 treatments for 8 weeks. The control group consisted of an Internet physical activity program. The Internet plus generic text message group consisted of the same Internet physical activity program and included daily generic text messages. The Internet plus culturally tailored text message group consisted of the Internet physical activity program and included daily culturally tailored text messages. Zero-inflated Poisson mixed models showed that the overall effect of the treatment group on the login rates varied significantly across individuals. The login rates over time were significantly higher in the Internet plus culturally tailored text message group than the control group (ß = 46.06, 95% CI 13.60, 156.02; p = .002) and the Internet plus generic text message group (ß = 15.80, 95% CI 4.81, 51.9; p = .021) after adjusting for covariates. These findings suggest that culturally tailored text messages may be more advantageous than generic text messages on improving adolescents' website login rate, but effects varied significantly across individuals. Our results support the inclusion of culturally tailored messaging in future online physical activity interventions.


Assuntos
Comunicação em Saúde/métodos , Promoção da Saúde/estatística & dados numéricos , Internet/estatística & dados numéricos , Atividade Motora , Envio de Mensagens de Texto , Adolescente , Criança , Características Culturais , Feminino , Hong Kong , Humanos , Masculino , Avaliação de Programas e Projetos de Saúde
9.
Curr Sports Med Rep ; 13(4): 240-5, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25014389

RESUMO

The effects of overweight and obesity on chronic diseases, particularly on cardiovascular disease (CVD), and its impact on increasing CVD risk factors and total CVD are reviewed. However despite the adverse effects of obesity on CVD risk factors and CVD, obesity has a surprising association with prognosis in patients with established diseases, often showing an "obesity paradox," [corrected] where overweight (body mass index (BMI), 25 to 29.9 kg·m(-2)) and obese patients (BMI, ≥30 kg·m(-2)) with established CVD frequently have a better prognosis than that of their leaner counterparts (BMI, <25 kg·m(-2)) with the same diseases. Fitness-versus-fatness debate is summarized also, including the critical role that fitness plays to alter the relationship between adiposity and subsequent prognosis.


Assuntos
Índice de Massa Corporal , Doenças Cardiovasculares/diagnóstico , Obesidade/diagnóstico , Aptidão Física/fisiologia , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/fisiopatologia , Doença Crônica , Humanos , Obesidade/epidemiologia , Obesidade/fisiopatologia , Aptidão Física/psicologia , Prognóstico , Fatores de Risco
10.
Polymers (Basel) ; 16(5)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38475263

RESUMO

This study focuses on evaluating the fatigue life performance of 3D-printed polymer composites produced through the fused deposition modelling (FDM) technique. Fatigue life assessment is essential in designing components for industries like aerospace, medical, and automotive, as it provides an estimate of the component's safe service life during operation. While there is a lack of detailed research on the fatigue behaviour of 3D-printed polymer composites, this paper aims to fill that gap. Fatigue tests were conducted on the 3D-printed polymer composites under various loading conditions, and static (tensile) tests were performed to determine their ultimate tensile strength. The fatigue testing load ranged from 80% to 98% of the total static load. The results showed that the fatigue life of the pressed samples using a platen press was significantly better than that of the non-pressed samples. Samples subjected to fatigue testing at 80% of the ultimate tensile strength (UTS) did not experience failure even after 1 million cycles, while samples tested at 90% of UTS failed after 50,000 cycles, with the failure being characterized as splitting and clamp area failure. This study also included a lap shear analysis of the 3D-printed samples, comparing those that were bonded using a two-part Araldite glue to those that were fabricated as a single piece using the Markforged Mark Two 3D printer. In summary, this study sheds light on the fatigue life performance of 3D-printed polymer composites fabricated using the FDM technique. The results suggest that the use of post-printing platen press improved the fatigue life of 3D-printed samples, and that single printed samples have better strength of about 265 MPa than adhesively bonded samples in which the strength was 56 MPa.

11.
12.
Prog Cardiovasc Dis ; 79: 56-64, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36283496

RESUMO

This paper presents two inter-dependent frameworks for understanding the etiology of obesity and the regain of body and fat mass after weight loss. The 'Invisible Hand of Metabolism' illustrates how physiologic states such as body and fat mass and blood glucose levels arise from the unregulated, uncontrolled, yet competitive behavior of trillions of semi-autonomous cells. The 'Competition Model of Metabolism' is an explanatory (mechanistic) framework that details how organismal and cell-specific behaviors generate the apparent stability of physiologic states despite metabolic perturbations (e.g., weight-loss and exercise). Together, these frameworks show that body and fat mass and blood glucose levels are not regulated, controlled, or defended but emerge from the complexity and functional plasticity of competitive cellular relations. Therefore, we argue that the use of abstract constructs such as 'regulation', 'control', 'glucostats', 'adipostats', and 'set-/settling-points' hinders the understanding of obesity and cardiometabolic diseases in human and nonhuman mammals.

13.
Metabolites ; 13(4)2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37110203

RESUMO

During the prenatal period, maternal and fetal cells compete for calories and nutrients. To ensure the survival of the mother and development of the fetus, the prenatal hormonal milieu alters the competitive environment via metabolic perturbations (e.g., insulin resistance). These perturbations increase maternal caloric consumption and engender increments in both maternal fat mass and the number of calories captured by the fetus. However, a mother's metabolic and behavioral phenotypes (e.g., physical activity levels) and her external environment (e.g., food availability) can asymmetrically impact the competitive milieu, leading to irreversible changes in pre- and post-natal development-as exhibited by stunting and obesity. Therefore, the interaction of maternal metabolism, behavior, and environment impact the competition for calories-which in turn creates a continuum of health trajectories in offspring. In sum, the inheritance of metabolic phenotypes offers a comprehensive and consilient explanation for much of the increase in obesity and T2DM over the past 50 years in human and non-human mammals.

14.
Sci Total Environ ; 859(Pt 1): 160034, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36356746

RESUMO

Chemical pollution (including chemicals of emerging concern - CECs) continues to gain increasing attention as a global threat to human health and the environment, with numerous reports on the adverse and sometimes devastating effects upon ecosystems the presence of these chemicals can have. Whilst many studies have investigated presence of CECs in aquatic environments, these studies have been often focused on higher income countries, leaving significant knowledge gaps for many low-middle income countries. This study proposes a new integrated powerless, in-situ multi-mode extraction (iMME) sampler for the analysis of chemicals (105 CECs) and biological (5 genes) markers in water in contrasting settings: an urbanized Avon River in the UK and remote Olifants River in Kruger National Park in South Africa. The overarching goal was to develop a sampling device that maintains integrity of a diverse range of analytes via analyte immobilization using polymeric and glass fibre materials, without access to power supply or cold chain (continuous chilled storage) for sample transportation. Chemical analysis was achieved using ultra-performance liquid chromatography coupled with tandem mass spectrometry. Several mobile CECs showed low stability in river water, at room temperature and typical 24 h sampling/transport time. It is therefore recommended that, in the absence of cooling, environmental water samples are spiked with internal standards on site, immediately after collection and analyte immobilization option is considered, in order to allow fully quantitative analysis. iMME has proven effective in immobilization, concentration and increased stability of CECs at room temperature (and at least 7 days storage) allowing for sample collection at remote locations. The results from the River Avon and Olifants River sampling indicate that the pristine environment of Olifants catchment is largely unaffected by CECs common in the urbanized River Avon in the UK with a few exceptions: lifestyle chemicals (e.g., caffeine, nicotine and their metabolites), paracetamol and UV filters due to tourism and carbamazepine due to its persistent nature. iMME equipped with an additional gene extraction capability provides an exciting new opportunity of comprehensive biochemical profiling of aqueous samples with one powerless in-situ device. Further work is required to provide full integration of the device and comprehensive assessment of performance in both chemical and biological targets.


Assuntos
Monitoramento Ambiental , Poluentes Químicos da Água , Humanos , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Água/análise , Ecossistema , Cromatografia Gasosa-Espectrometria de Massas
15.
Water Res ; 240: 120110, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37247434

RESUMO

There has been a significant increase in antimicrobial agents (AAs) usage, globally - however the relative consumption is unevenly distributed between nations. Inappropriate use of antibiotics can harbour inherent antimicrobial resistance (AMR); therefore, it is important to understand and monitor community-wide prescribing and consumption behaviours throughout different communities around the world. Wastewater-Based Epidemiology (WBE) is a novel tool enabling low cost and large scale studies focussed on AA usage patterns. The back-calculation of community antimicrobial intake was performed from quantities measured in municipal wastewater and informal settlement discharge in the city of Stellenbosch, utilising WBE. Seventeen antimicrobials, and their human metabolites, were evaluated, in concordance with prescription records corresponding to the catchment region. The proportional excretion, biological/chemical stability, and method recovery of each analyte were all crucial factors in the efficacy of the calculation. Mass per day measurements were normalised to the catchment area via population estimates. Municipal wastewater treatment plant population estimates were used to normalise the wastewater samples and prescription data (mg/day/1000 inhabitants). Population estimates for the informal settlements were less accurate due to a lack of reliable sources that were relevant to the sampling time period. Both mass loads and normalised loads suggested higher than average usage throughout the settlements, relative to municipal wastewater. This was seen most prominently in emtricitabine and lamivudine; but also, sulfamethoxazole, trimethoprim, sulfadiazine, clindamycin, ciprofloxacin, ofloxacin, and doxycycline. Urban water fingerprinting (UWF) data triangulation with prescription datasets showed good correlations for several antimicrobial agents (AAs) (e.g., clindamycin, clarithromycin, ofloxacin, and doxycycline). It also revealed discrepancies in usage for some compounds (e.g., tetracycline and sulfapyridine). This might be linked with a lack of pharma compliance in prescription datasets; erroneous association of prescription boundaries with the sewerage catchment; and/or uncertainties within the sewerage catchment (e.g., population estimations). The UWF tool provided a comprehensive overview of multiclass AAs usage, both prescription and over-the counter. For example, tetracycline was not reported in available prescription statistics, but was detected at an average of 18.4 mg/day/1000inh; and no antiviral prescriptions were obtained, but emtricitabine and lamivudine were quantified at 2415.4 and 144.4 mg/day/1000inh, respectively. A lack of clarity regarding prescriptions and a lack of inclusion of several critical (often over-the-counter) medications in public health databases makes WBE a useful and comprehensive epidemiology tool for tracking pharma usage within a catchment.


Assuntos
Antibacterianos , Poluentes Químicos da Água , Humanos , Águas Residuárias , Clindamicina , Doxiciclina , África do Sul , Lamivudina , Ofloxacino , Poluentes Químicos da Água/análise
16.
Front Microbiol ; 14: 1283835, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38029182

RESUMO

Salmonella enterica are important foodborne bacterial pathogens globally associated with poultry. Exposure to Salmonella-contaminated eggs and egg-related products is a major risk for human salmonellosis. Presently, there is a huge data gap regarding the prevalence and circulating serovars of Salmonella in chicken eggs sold in Ghana. In this study, 2,304 eggs (pools of six per sample unit) collected from informal markets in Accra, Kumasi and Tamale, representing the three ecological belts across Ghana, were tested for Salmonella. Antimicrobial susceptibility testing and Whole Genome Sequencing (WGS) of the isolates were performed using standard microdilution protocols and the Illumina NextSeq platform, respectively. The total prevalence of Salmonella was 5.5% with a higher rate of contamination in eggshell (4.9%) over egg content (1.8%). The serovars identified were S. Ajiobo (n = 1), S. Chester (n = 6), S. Hader (n = 7), S. enteritidis (n = 2); and S. I 4:b:- (n = 8). WGS analysis revealed varied sequence types (STs) that were serovar specific. The S. I 4:b:- isolates had a novel ST (ST8938), suggesting a local origin. The two S. enteritidis isolates belonged to ST11 and were identified with an invasive lineage of a global epidemic clade. All isolates were susceptible to ampicillin, azithromycin, cefotaxime, ceftazidime, gentamicin, meropenem, and tigecycline. The phenotypic resistance profiles to seven antimicrobials: chloramphenicol (13%), ciprofloxacin (94%), and nalidixic acid (94%), colistin (13%), trimethoprim (50%) sulfamethoxazole (50%) and tetracycline (50%) corresponded with the presence of antimicrobial resistance (AMR) determinants including quinolones (gyrA (D87N), qnrB81), aminoglycosides (aadA1), (aph(3")-Ib aph(6)-Id), tetracyclines (tet(A)), phenicols (catA1), trimethoprim (dfrA14 and dfrA1). The S. enteritidis and S. Chester isolates were multidrug resistant (MDR). Several virulence factors were identified, notably cytolethal distending toxin (cdtB gene), rck, pef and spv that may promote host invasion and disease progression in humans. The findings from this study indicate the presence of multidrug resistant and virulent strains of Salmonella serovars in Ghanaian chicken eggs, with the potential to cause human infections. This is a critical baseline information that could be used for Salmonella risk assessment in the egg food chain to mitigate potential future outbreaks.

19.
Nutrients ; 14(11)2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35684086

RESUMO

The etiology of obesity is complex and idiosyncratic-with inherited, behavioral, and environmental factors determining the age and rate at which excessive adiposity develops. Moreover, the etiologic status of an obese phenotype (how and when it developed initially) strongly influences both the short-term response to intervention and long-term health trajectories. Nevertheless, current management strategies tend to be 'one-size-fits-all' protocols that fail to anticipate the heterogeneity of response generated by the etiologic status of each individual's phenotype. As a result, the efficacy of current lifestyle approaches varies from ineffective and potentially detrimental, to clinically successful; therefore, we posit that effective management strategies necessitate a personalized approach that incorporates the subtyping of obese phenotypes. Research shows that there are two broad etiologic subtypes: 'acquired' and 'inherited'. Acquired obesity denotes the development of excessive adiposity after puberty-and because the genesis of this subtype is behavioral, it is amenable to interventions based on diet and exercise. Conversely, inherited obesity subsumes all forms of excessive adiposity that are present at birth and develop prior to pubescence (pediatric and childhood). As the inherited phenotype is engendered in utero, this subtype has irreversible structural (anatomic) and physiologic (metabolic) perturbations that are not susceptible to intervention. As such, the most realizable outcome for many individuals with an inherited subtype will be a 'fit but fat' phenotype. Given that etiologic subtype strongly influences the effects of intervention and successful health management, the purpose of this 'perspective' article is to provide a concise overview of the differential development of acquired versus inherited obesity and offer insight into subtype-specific management.


Assuntos
Adiposidade , Obesidade , Criança , Exercício Físico , Humanos , Estilo de Vida , Obesidade/genética , Obesidade/prevenção & controle , Fenótipo
20.
Materials (Basel) ; 15(3)2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35160944

RESUMO

Additively manufactured composite specimens exhibit anisotropic properties, meaning that the elastic response changes with respect to orientation. Both in-plane and out-of-plane mechanical properties are important for designing purpose. Recent studies have characterised the in-plane performance. In this study, however, through-thickness tensile strength of 3D polymer composites were determined by printing of continuous carbon fibre reinforced thermoplastic polyamide-based composite, manufactured using a Markforged Two 3D printer. This paper discusses sample fabrication and geometry, adhesive used, and testing procedure. Test standards used to determine out-of-plane properties are tedious as most of the premature failures occur between the specimens and the tabs. Two types of samples were printed according to ASTM flatwise tension standard and the results were compared to determine the geometry effect on the interlaminar strength. This test method consists of subjecting the printed sample to a uniaxial tensile force normal to the plane. With this method, the acceptable failure modes for tensile strength must be internal to the structure, not between the sample and the end tabs. Micro-computed tomography (µCT) was carried out to observe the porosity. Surface behaviour was studied using scanning electron microscopy (SEM) to see the voids and the distribution of the fibres in the samples. The results showed consistent values for tensile strength and elastic modulus for Araldite glue after initial trials (with some other adhesives) to determine a suitable choice of adhesive for bonding the samples with the tabs. Circular specimens have higher tensile strength and elastic modulus as compared to rectangular specimens.

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