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1.
Brain Behav Immun ; 102: 325-332, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35301057

RESUMEN

INTRODUCTION: Obesity in adulthood is associated with reduced physical functioning (PF) at older ages. However, mechanisms underpinning this association are not well understood. We investigated whether and the extent to which C-reactive protein (CRP) mediates the association between early-adult obesity and mid-life PF. METHODS: We used data from 8495 participants in the 1958 British birth cohort study. Body mass index (BMI), CRP and PF were measured at 33, 45 and 50y, respectively. Poor PF was defined as the lowest (sex-specific) 10% on the Short-form 36 Physical Functioning subscale. We accounted for prospectively measured confounders in early-life (e.g., social class at birth) and in mid-adulthood (e.g., 42y comorbidities). We decomposed the total effect of early-adult obesity on mid-life PF into direct and indirect (via CRP) effects, by employing a mediation analysis based on parametric g-computation. RESULTS: The estimated total effect of obesity at 33y on poor PF at 50y, expressed as an odds ratio (OR), was 2.41 (95% CI: 1.89, 3.08). The direct effect of obesity on poor PF (i.e., not operating via CRP), was 1.97 (95% CI: 1.51, 2.56), with an indirect effect of 1.23 (95% CI: 1.10, 1.37). As such, the proportion of the total effect which was mediated by the effect of obesity on CRP at 45y, was 23.27% (95% CI: 8.64%, 37.90%). CONCLUSION: Obesity in early-adulthood was associated with over twice the odds of poor PF in mid-life, with approximately 23% of the obesity effect operating via a downstream effect on CRP. As current younger generations are likely to spend greater proportions of their life course in older age and with obesity, both of which are associated with poor PF, there is an urgent need to identify mechanisms, and thus potential modifiable intermediaries, linking obesity to poor PF.


Asunto(s)
Proteína C-Reactiva , Obesidad , Adulto , Índice de Masa Corporal , Proteína C-Reactiva/análisis , Estudios de Cohortes , Femenino , Humanos , Recién Nacido , Masculino , Obesidad/complicaciones , Obesidad/epidemiología , Clase Social
2.
Acta Trop ; 225: 106214, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34687641

RESUMEN

Leptospirosis is one of the most widely distributed zoonosis in the world. Bovine leptospirosis is a serious problem in bovine production, causing reproductive losses. The aim of this work was to compare recombinant LipL32 with sonicated antigen for detecting anti-Leptospira IgG antibodies in bovine serum using ELISA. The Microscopic Agglutination Test (MAT) is used as the gold standard. Sonicated antigen from cultures of Leptospira interrogans serogroup Icterohaemorrhagiae serovar copenhageni (strain M20) was used for the eELISA and rLipL32 for the rELISA. The performance of these assays was evaluated using serum samples from 166 bovines, 69 MAT positive and 97 MAT negative. At the optimal cut-off point recommended by the receiver operating characteristic (ROC) curve analysis, the sensitivity and specificity values were 98.6% and 97.9%, respectively, for eELISA, and 85.5% and 86.6% respectively, for rELISA. The value for the area under the ROC curve was 0.998 (0.994-1.0) (CI 95%) for eELISA and 0.929 (0.891-0.968) (CI 95%) for rELISA. The ROC curves for rLipL32 and sonicated antigen showed statistically significant differences (z = -3.826; p = 0.000). A three-way comparison showed statistically significant differences in the sensitivity and specificity of rELISA and eELISA. Our results showed that eELISA was more specific and sensitive than rELISA. The difference in performance (eELISA-rELISA) was 13.4% (4.03-23.28) (CI 95%) for sensitivity and 11.34 % (4.07-19.56) (CI 95%) for specificity. Our results show that the eELISA has a better diagnostic performance than rELISA for the detection of anti-Leptospira IgG antibodies in bovine serum.


Asunto(s)
Leptospira , Leptospirosis , Pruebas de Aglutinación , Anticuerpos Antibacterianos , Ensayo de Inmunoadsorción Enzimática , Humanos , Leptospirosis/diagnóstico , Leptospirosis/veterinaria
3.
FAVE, Secc. Cienc. vet. (En línea) ; 20(2): 91-96, jul. 2021. tab, graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1375467

RESUMEN

Resumen La leptospirosis continúa siendo hoy en día un problema para la salud pública, principalmente en poblaciones de bajos recursos socioeconómicos. En este trabajo se presenta la detección de leptospiras patógenas en muestras ambientales (aguas y barros) provenientes de regiones del norte argentino (provincias de Formosa, Salta, Santiago del Estero, Misiones y Chaco) con variadas características climatológicas habitadas por poblaciones vulnerables. De las 89 muestras analizadas, en el 24,7% fue posible detectar molecularmente la presencia de leptospiras patógenas. La prevalencia por tipo de muestra fue de 27,8% para las aguas y 11,8% para los barros. Todas las localidades muestreadas presentaron al menos una muestra positiva a alguna de las pruebas realizadas, por lo que el presente trabajo refleja la necesidad de profundizar los estudios de la leptospirosis en distintas regiones de la Argentina.


Abstract Leptospirosis remains as a major public health problem nowadays, mainly affecting vulnerable communities with low socioeconomic resources. In this study, the molecular detection of pathogenic leptospires from environmental samples (water and mud) from northern Argentina (Formosa, Salta, Santiago del Estero, Misiones and Chaco provinces) is described. Samples were obtained from regions with varied climatological features, all inhabited by vulnerable communities. From the 89 samples that were analyzed, 24.7% showed molecular evidence of the presence of pathogenic leptospires. Prevalence by sample type was: 27.8% in water samples and 11.8% in mud samples. All the sampled regions showed at least one positive sample. This result highlights the need of further research regarding leptospirosis in different regions of Argentina.

4.
BMC Med ; 19(1): 96, 2021 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-33879138

RESUMEN

BACKGROUND: Most studies on secular trends in body mass index (BMI) are cross-sectional and the few longitudinal studies have typically only investigated changes over time in mean BMI trajectories. We aimed to describe how the evolution of the obesity epidemic in Great Britain reflects shifts in the proportion of the population demonstrating different latent patterns of childhood-to-adulthood BMI development. METHODS: We used pooled serial BMI data from 25,655 participants in three British cohorts: the 1946 National Survey of Health and Development (NSHD), 1958 National Child Development Study (NCDS), and 1970 British Cohort Study (BCS). Sex-specific growth mixture models captured latent patterns of BMI development between 11 and 42 years. The classes were characterised in terms of their birth cohort composition. RESULTS: The best models had four classes, broadly similar for both sexes. The 'lowest' class (57% of males; 47% of females) represents the normal weight sub-population, the 'middle' class (16%; 15%) represents the sub-population who likely develop overweight in early/mid-adulthood, and the 'highest' class (6%; 9%) represents those who likely develop obesity in early/mid-adulthood. The remaining class (21%; 29%) reflects a sub-population with rapidly 'increasing' BMI between 11 and 42 years. Both sexes in the 1958 NCDS had greater odds of being in the 'highest' class compared to their peers in the 1946 NSHD but did not have greater odds of being in the 'increasing' class. Conversely, males and females in the 1970 BCS had 2.78 (2.15, 3.60) and 1.87 (1.53, 2.28), respectively, times higher odds of being in the 'increasing' class. CONCLUSIONS: Our results suggest that the obesity epidemic in Great Britain reflects not only an upward shift in BMI trajectories but also a more recent increase in the number of individuals demonstrating more rapid weight gain, from normal weight to overweight, across the second, third, and fourth decades of life.


Asunto(s)
Desarrollo Infantil , Adulto , Anciano , Índice de Masa Corporal , Niño , Estudios de Cohortes , Estudios Transversales , Femenino , Humanos , Estudios Longitudinales , Masculino , Factores de Riesgo , Reino Unido/epidemiología
5.
FAVE, Secc. Cienc. vet. (En línea) ; 20(1): 11-12, ene. 2021. tab, graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1375455

RESUMEN

Abstract Molecular tools have improved conventional veterinary diagnosis. Acid nucleic extraction is a key step for downstream applications. This work aimed to compare the DNA extraction method Chelex-100 resin (M1) with Whatman® cards (M2), phenol-chloroform (M3), or commercial kits (M4), and to determine the most sensitive and inexpensive one for its diagnosis of animal pathogens that, despite their economic or zoonotic relevance, receive little attention. DNA was isolated from urine, organs, semen, blood and intestinal mucous, from the bacteria Leptospira interrogans serovar Pomona Pomona (by M1 and M2), Brucella melitensis (by M1, M3 and M4), and Salmonella ser. Abortusequi (by M1 and M4), and the parasites Leishmania spp. (by M1, M3 and M4), and Eimeria spp. (by M1 and M3), respectively. The sensitivity of each method was assayed by Polymerase Chain Reaction (PCR). The M1 showed similar sensitivity for Salmonella ser. Abortusequi, Leishmania spp., and Eimeria spp., being better for L. interrogans serovar Pomona Pomona and slightly lower for B. melitensis. For the first time, a simple and economic method was successfully employed for extracting DNA from these animal pathogens, especially important in low-resource settings, contributing to the diagnosis of leptospirosis, brucellosis, leishmaniasis, and coccidiosis; as well as to the molecular epidemiology of salmonellosis in stallion from semen samples.


Resumen Las técnicas moleculares han contribuido a mejorar el diagnóstico veterinario tradicional y la extracción de ácidos nucleicos es determinante. El objetivo de este trabajo fue comparar el método de extracción de ADN Chelex-100 (M1) con papel Whatman (M2), fenol-cloroformo (M3) o kits comerciales (M4), y determinar un método sensible y de bajo costo para el diagnóstico de patógenos de animales económica o zoonóticamente relevantes y que reciben poca atención. A partir de orina, órganos, semen, sangre y mucosa intestinal se extrajo el ADN de las bacterias Leptospira interrogans serovar Pomona Pomona (con M1 y M2), Brucella melitensis (con M1, M3 y M4), Salmonella ser. Abortusequi (M1 y M4), y de los parásitos Leishmania spp. (M1, M3 y M4) y Eimeria spp. (M1 y M3), respectivamente. La sensibilidad de los protocolos fue analizada por PCR. El método M1 demostró una sensibilidad similar para S. Abortusequi, Leishmania spp. y Eimeria spp., siendo mejor para L. interrogans y levemente menor para B. melitensis. Por primera vez se usó exitosamente en estos patógenos veterinarios un método simple y económico para extraer ADN, especialmente importante en laboratorios de bajos recursos económicos, contribuyendo al diagnóstico de leptospirosis, brucelosis, leishmaniasis y coccidiosis, así como también a la epidemiología molecular de salmonelosis en muestras de semen de caballos.

6.
Diabet Med ; 38(2): e14392, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32852105

RESUMEN

AIMS: This study aimed to examine the cross-sectional associations of thigh accelerometry-assessed sedentary behaviour and moderate-to-vigorous physical activity (MVPA) with cardio-metabolic health markers and prevalent diabetes in a population sample of middle-aged British adults. METHODS: Participants (n = 4892) from the age-46-to-48 wave of the 1970 British Cohort Study were fitted with a waterproofed activPAL3 micro device. Total/prolonged sedentary time, breaks and MVPA were the main exposures. We dichotomized prolonged sedentary time and MVPA based on the corresponding median, generating four combinations as categorical exposures. Outcomes comprised of diabetes and seven cardio-metabolic health markers. We used logistic regression and generalized linear models to examine independent/joint associations, conducting a minimally adjusted model including demographics and contextual covariates, and further adjusted for total sedentary time and/or MVPA as applicable. RESULTS: Each set of 10 sedentary breaks and 1 h of prolonged sedentary time were associated with HbA1c (mmol/mol) [B = -0.18 (-0.33, -0.03) and 2.35 (1.01, 3.69), respectively]. Each set of 10 sedentary breaks and 1 h of MVPA were favourably associated with diabetes [adjusted odds ratio (AOR): 0.80 (0.71, 0.99) and 0.42 (0.26, 0.67), respectively]. Joint analyses showed that only the low MVPA × long sedentary time combination had significantly higher odds for diabetes than the referent high MVPA × short sedentary time combination [AOR: 1.89 (1.17, 3.03)]. CONCLUSIONS: Each set of additional 10 sedentary breaks per day was associated with 20% lower odds for diabetes. A low physical activity level combined with long sedentary time might synergistically deteriorate cardio-metabolic health.


Asunto(s)
Factores de Riesgo Cardiometabólico , Diabetes Mellitus/epidemiología , Ejercicio Físico/estadística & datos numéricos , Conducta Sedentaria , Acelerometría , Tejido Adiposo , Presión Sanguínea , Índice de Masa Corporal , Proteína C-Reactiva/metabolismo , Colesterol/metabolismo , HDL-Colesterol/metabolismo , Estudios de Cohortes , Diabetes Mellitus/metabolismo , Femenino , Hemoglobina A Glucada/metabolismo , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Factores de Tiempo , Triglicéridos/metabolismo , Reino Unido
7.
Nat Commun ; 11(1): 3054, 2020 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-32528007

RESUMEN

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

8.
Nat Commun ; 11(1): 2339, 2020 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-32393747

RESUMEN

Electron-electron interactions play a critical role in many condensed matter phenomena, and it is tempting to find a way to control them by changing the interactions' strength. One possible approach is to place a studied system in proximity of a metal, which induces additional screening and hence suppresses electron interactions. Here, using devices with atomically-thin gate dielectrics and atomically-flat metallic gates, we measure the electron-electron scattering length in graphene and report qualitative deviations from the standard behavior. The changes induced by screening become important only at gate dielectric thicknesses of a few nm, much smaller than a typical separation between electrons. Our theoretical analysis agrees well with the scattering rates extracted from measurements of electron viscosity in monolayer graphene and of umklapp electron-electron scattering in graphene superlattices. The results provide a guidance for future attempts to achieve proximity screening of many-body phenomena in two-dimensional systems.

9.
Br J Dermatol ; 182(6): 1379-1387, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31519034

RESUMEN

BACKGROUND: The underlying phenotypic correlations between wrinkles, pigmented spots (PS), telangiectasia and other related facial-ageing subphenotypes are not well understood. OBJECTIVES: To analyse the underlying phenotypic correlation structure between seven features for facial ageing: global wrinkling, perceived age (PA), Griffiths photodamage grading, PS, telangiectasia, actinic keratosis (AK) and keratinocyte cancer (KC). METHODS: This was a cross-sectional study. Facial photographs and a full-body skin examination were used. We used principal component analysis (PCA) to derive principal components (PCs) of common variation between the features. We performed multivariable linear regressions between age, sex, body mass index, smoking and ultraviolet radiation exposure and the PC scores derived from PCA. We also tested the association between the main PC scores and 140 single-nucleotide polymorphisms (SNPs) previously associated with skin-ageing phenotypes. RESULTS: We analysed data from 1790 individuals with complete data on seven features of skin ageing. Three main PCs explained 73% of the total variance of the ageing phenotypes: a hypertrophic/wrinkling component (PC1: global wrinkling, PA and Griffiths grading), an atrophic/skin colour component (PC2: PS and telangiectasia) and a cancerous component (PC3: AK and KC). The associations between lifestyle and host factors differed per PC. The strength of SNP associations also differed per component with the most SNP associations found with the atrophic component [e.g. the IRF4 SNP (rs12203592); P-value = 1·84 × 10-22 ]. CONCLUSIONS: Using a hypothesis-free approach, we identified three major underlying phenotypes associated with extrinsic ageing. Associations between determinants for skin ageing differed in magnitude and direction per component. What's already known about this topic? Facial ageing is a complex phenotype consisting of different features including wrinkles, pigmented changes, telangiectasia and cancerous-related growths; it is not clear how these phenotypes are related to each other and to other phenotypes. A few studies have described two main clinical phenotypes for photoageing, namely hypertrophic ageing and atrophic ageing, which have been based solely on the clinical assessment of photoageing characteristics. What does this study add? We are the first to use epidemiology data to identify three main components associated with photoageing, namely a hypertrophic component (global wrinkling; perceived age; Griffiths grading) and atrophic component (pigmented spots; telangiectasia) and a cancer component (actinic keratosis; keratinocyte cancer). Association analysis showed different effects and direction of environmental determinants and genetic associations with the three components, with the most significant gene variants associations found for the atrophic component.


Asunto(s)
Envejecimiento de la Piel , Estudios Transversales , Humanos , Análisis de Componente Principal , Envejecimiento de la Piel/genética , Pigmentación de la Piel/genética , Rayos Ultravioleta/efectos adversos
10.
J Eur Acad Dermatol Venereol ; 34(4): 821-826, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31593313

RESUMEN

BACKGROUND: Telangiectasia or red veins are one of the prominent features of facial skin ageing. To date, there are few studies investigating the determinants of telangiectasia. OBJECTIVES: We investigated lifestyle and physiological factors associated with facial telangiectasia in a large prospective Dutch cohort study. METHODS: Telangiectasia was quantified digitally from standardized facial photographs of 2842 North European participants (56.8% female, median age 66.9) from the Rotterdam Study, collected in 2010-2013. Effect estimates from multivariable linear regressions are presented as the percentage difference in the mean value of telangiectasia area per unit increase of a determinant (%Δ) with corresponding 95% CI. RESULTS: Significant determinants were older age [1.7%Δ per year (95% CI 1.4, 2.0)], female sex [18.3%Δ (95% CI 13.2, 23.6)], smoking [current versus never 38.4%Δ (95% CI 30.3, 47.0); former versus never 11.6%Δ (95% CI 6.6, 16.9)], a high susceptibility to sunburn [10.2%Δ (95% CI 5.4, 15.3)] and light skin colour [pale versus white-to-olive 31.4%Δ (95% CI 19.7, 44.1]; white vs. white-to-olive 9.2%Δ (95% CI 2.8, 16.0)]. CONCLUSIONS: In this large cohort study, we confirmed known and described new determinants of facial telangiectasia.


Asunto(s)
Cara/irrigación sanguínea , Telangiectasia/epidemiología , Telangiectasia/etiología , Factores de Edad , Anciano , Estudios Transversales , Femenino , Humanos , Estilo de Vida , Masculino , Países Bajos/epidemiología , Estudios Prospectivos , Factores de Riesgo , Factores Sexuales
11.
FAVE, Secc. Cienc. vet. (En línea) ; 18(2): 68-73, dic. 2019. ilus, tab
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1090386

RESUMEN

La leptospirosis bovina es una importante enfermedad zoonótica cuyo diagnóstico molecular está ampliamente divulgado. Sin embargo, no existe un método único de extracción de ADN para leptospiras patógenas a partir de muestras clínicas. En este trabajo se utilizó orina bovina contaminada con cultivo de L. interrogans serovar Pomona Pomona para analizar el mejor método comparando: M1.) resina Chelex-100, M2.) papel FTA Whatman y M3.) hervido de la muestra (protocolo casero). De estas tres técnicas, la primera (M1) presentó la mayor sensibilidad al realizar la PCR de diagnóstico, detectándose hasta 2x102 leptospiras/mL. La metodología aquí planteada resultó tener buen rendimiento para la detección de leptospiras en muestras clínicas animales, aunque es necesario su validación con mayor número y diversidad de muestras.


Bovine leptospirosis is an important zoonotic disease whose molecular diagnosis is widely reported. However, there is not a unique method of extraction of DNA for pathogenic leptospires using clinical samples. In this study, bovine urine was contaminated with pure culture of L. interrogans serovar Pomona Pomona in order to compare three of them: M1.) Chelex-100 resin, M2.) FTA Whatman paper and M3.) boiling of the sample (in-house protocol), being the first one the most sensitive when used in diagnostic PCR, detecting up to 2x102 leptospiras/mL. The methodology proposed in this study turned out to have good performance for the detection of leptospires in animal clinical samples, although it should be applied to a greater number of samples and in different stages of the pathology.

12.
J Pediatr Urol ; 15(5): 469.e1-469.e9, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31239100

RESUMEN

INTRODUCTION: Although there are significant demographic and clinical variations in treatment decisions for infants with high-grade hydronephrosis concerning for ureteropelvic junction obstruction (UPJO), there has been little research on the roles of parents and surgeons in the surgical decision-making (DM) process. OBJECTIVE: The purpose of this study was to understand parents' and surgeons' perceived roles in the surgical DM process for infants with high-grade hydronephrosis. STUDY DESIGN: Semistructured interviews were conducted with pediatric urologists from three regionally diverse tertiary referral sites and parents of infants diagnosed and treated for unilateral Society for Fetal Urology grade 3 or 4 hydronephrosis at one tertiary pediatric urology practice. Purposive sampling was used to ensure adequate representation of parents based on treatment choice, patient gender, race/ethnicity, and distance from the practice. Survey domains included (1) discussions about diagnosis and treatment options, (2) factors guiding treatment choice, and (3) participants' role in the DM process. Transcribed data and field notes were analyzed using a team-based, inductive grounded theory qualitative approach. RESULTS: Thirteen physicians and 32 parents were interviewed between November 2016 and November 2017. Parents and surgeons agreed that the surgeon was best equipped to guide treatment decisions because of their clinical knowledge and experience. Parents reported that their trust in the surgeon was the primary factor in their decisions. Surgeons reported tailoring discussions with parents to not only educate them about treatment options but also to develop an ongoing relationship with parents. Both parents and surgeons reported being satisfied with their roles in the DM process. DISCUSSION: This study suggests that parental trust in the surgeon and surgeon recommendations drive DM. This may be due to a lack of explicit discussion of options or of parental values and preferences for care. Limited discussions may also impact parental understanding of risks and potential complications. These findings are similar to those of prior studies in adults and children considering elective surgery. CONCLUSIONS: In this study, parents and surgeons reported that surgeon recommendations, rather than parent preferences, guide treatment choices for infants with suspected UPJO. Both parents and surgeons are satisfied with a physician-driven approach to DM, suggesting that, in situations where the perceived risk is low and parental knowledge is limited, parents may find a physician-led approach beneficial. Data gleaned from this study will be used to inform future quantitative studies evaluating factors guiding surgeon recommendations for treatment and their associations with underlying treatment variation.


Asunto(s)
Toma de Decisiones Clínicas , Pelvis Renal/cirugía , Investigación Cualitativa , Participación de los Interesados , Obstrucción Ureteral/cirugía , Procedimientos Quirúrgicos Urológicos/métodos , Urólogos , Femenino , Estudios de Seguimiento , Humanos , Lactante , Pelvis Renal/diagnóstico por imagen , Masculino , Estudios Retrospectivos , Obstrucción Ureteral/diagnóstico
13.
J Intern Med ; 284(4): 439-443, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29776014

RESUMEN

BACKGROUND: Physical activity may be beneficial for cognition but mechanisms are unclear. We examined the association between objectively assessed physical activity and brain volume, with a focus on the hippocampus region. METHODS: We used data from UK Biobank (n = 5272; aged 55.4 ± 7.5 years; 45.6% men) collected through 2013-2016. Participants wore the Axivity AX3 wrist-worn triaxial accelerometer for 7 days to assess habitual physical activity. Structural magnetic resonance imaging was performed using a standard Siemens Skyra 3T running VD13A SP4 to obtain images of the brain. RESULTS: There was an association between physical activity (per SD increase) and grey matter volume after adjustment for a range of covariates, although this association was only detected in older adults (>60 years old). We also observed associations of physical activity with both left (B = 0.52, 95% CI, 0.01, 1.03; P = 0.046) and right hippocampal volume (B = 0.59, 95% CI, 0.08, 1.10; P = 0.024) in covariate-adjusted models. CONCLUSION: In summary, physical activity may play a role in the prevention of neurodegenerative diseases.


Asunto(s)
Encéfalo/patología , Ejercicio Físico/fisiología , Acelerometría , Bancos de Muestras Biológicas , Correlación de Datos , Femenino , Sustancia Gris/patología , Conductas Relacionadas con la Salud , Hipocampo/patología , Humanos , Estilo de Vida , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Tamaño de los Órganos/fisiología , Reino Unido
14.
Syst Rev ; 7(1): 50, 2018 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-29587826

RESUMEN

BACKGROUND: There is heterogeneity among obese individuals, as some appear to have healthier metabolic profiles and decreased health risks. These individuals are defined as metabolically healthy obese (MHO), whilst those with unhealthy metabolic profiles are defined as metabolically unhealthy obese (MUO). To date, most research on MHO has been cross-sectional or focused on disease prognosis. However, longitudinal studies are required to provide greater insight into the life course factors that contribute to the development of MHO. This study aims to systematically review longitudinal studies investigating the association between life course exposures and future MHO status. METHODS: Electronic databases (MEDLINE, SCOPUS, and Web of Science) will be searched using a trialled search strategy. Studies will be included following a double-screening process according to inclusion criteria to assess eligibility. Studies eligible for inclusion will include those that have a longitudinal observational design where a life course exposure occurred or was measured at least 1 year before the outcome, investigate a human study population, are published in English after 1956, and investigate the association between ≥ 1 life course exposure and ≥ 1 outcome that reflects a measure of cardiometabolic resilience to obesity. Accepted life course exposures will include body size, body composition, pubertal development, smoking, diet, physical activity, sedentary behaviour, and psychosocial stress. The primary measure of cardiometabolic resilience to obesity will be MHO as an outcome (at follow-up). Studies investigating the development of cardiometabolic risk factors in an obese group without specifying MHO will also be accepted, such as the development of the metabolic syndrome (MetS) in an obese group. Key results of included studies will be tabulated, and a narrative synthesis will be conducted. DISCUSSION: This will be the first systematic review to summarise the literature on the life course correlates of MHO. Importantly, it may highlight which modifiable lifestyle factors could be targeted to delay the onset of cardiometabolic complications among the obese. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42017057992.


Asunto(s)
Índice de Masa Corporal , Dieta , Síndrome Metabólico , Obesidad Metabólica Benigna , Ejercicio Físico , Estilo de Vida Saludable , Humanos , Estudios Longitudinales , Estrés Psicológico
15.
Pediatr Obes ; 13(2): 120-126, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28544804

RESUMEN

BACKGROUND: Children of South Asian decent born in the UK display lower levels of physical activity than British Caucasians although no longitudinal data are available. OBJECTIVES: We aimed to investigate change in activity levels over 1 year in a diverse ethnic sample of children residing in London, UK. METHODS: Children were categorized into ethnic groups (Caucasian/mixed, Black, South Asian). At baseline and 1-year follow-up, children's objective physical activity was monitored (Actigraph accelerometer) for at least 1 day. Mixed models were employed to investigate differences in change in activity levels between ethnic groups. RESULTS: A total of 281 children were included in the analyses. South Asians had a significantly greater increase in time spent sedentary at follow-up than those of a Caucasian/mixed ethnicity (B [ratio sedentary/wear time] = 0.024; 95% confidence interval 0.003, 0.046). South Asian children recorded lower moderate to vigorous physical activity at baseline (B = -6.5, 95% confidence interval, -11.1, -1.9 min d-1 , p = 0.006) although levels remained relatively stable over follow-up and changes did not differ across ethnic group. CONCLUSIONS: In a diverse ethnic sample of children from inner city London, those of a South Asian ethnicity exhibited a significantly greater increase in sedentary time over a period of 12 months in comparison with Caucasian/mixed and Black children.


Asunto(s)
/estadística & datos numéricos , Conducta Infantil , Ejercicio Físico , Conducta Sedentaria , /estadística & datos numéricos , Acelerometría/estadística & datos numéricos , Asia/etnología , Niño , Femenino , Humanos , Londres , Estudios Longitudinales , Masculino , Factores de Tiempo , Población Urbana/estadística & datos numéricos
16.
Nano Lett ; 17(10): 5950-5955, 2017 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-28906119

RESUMEN

Ultralight mechanical resonators based on low-dimensional materials are well suited as exceptional transducers of minuscule forces or mass changes. However, the low dimensionality also provides a challenge to minimize resistive losses and heating. Here, we report on a novel approach that aims to combine different two-dimensional (2D) materials to tackle this challenge. We fabricated a heterostructure mechanical resonator consisting of few layers of niobium diselenide (NbSe2) encapsulated by two graphene sheets. The hybrid membrane shows high quality factors up to 245,000 at low temperatures, comparable to the best few-layer graphene mechanical resonators. In contrast to few-layer graphene resonators, the device shows reduced electrical losses attributed to the lower resistivity of the NbSe2 layer. The peculiar low-temperature dependence of the intrinsic quality factor points to dissipation over two-level systems which in turn relax over the electronic system. Our high sensitivity readout is enabled by coupling the membrane to a superconducting cavity which allows for the integration of the hybrid mechanical resonator as a sensitive and low loss transducer in future quantum circuits.

17.
Int J Obes (Lond) ; 41(6): 866-872, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28220042

RESUMEN

BACKGROUND/OBJECTIVES: Some obese adults have a normal metabolic profile and are considered 'healthy', but whether they experience faster ageing than healthy normal-weight adults is unknown. We compared decline in physical function, worsening of bodily pain and likelihood of future mobility limitation and disability between these groups. SUBJECTS/METHODS: This was a population-based observational study using repeated measures over 2 decades (Whitehall II cohort data). Normal-weight (body mass index (BMI) 18.5-24.9 kg m-2), overweight (25.0-29.9 kg m-2) and obese (⩾30.0 kg m-2) adults were considered metabolically healthy if they had 0 or 1 of 5 risk factors (hypertension, low high-density lipoprotein cholesterol, high triacylglycerol, high blood glucose and insulin resistance) in 1991/1994. Decline in physical function and worsening of bodily pain based on change in Short Form Health Survey items using eight repeated measures over 18.8 years (1991/1994-2012/2013) were compared between metabolic-BMI groups using linear mixed models. Odds of mobility limitation based on objective walking speed (slowest tertile) and of disability based on limitations in ⩾1 of 6 basic activities of daily living, each using three repeated measures over 8.3 years (2002/2004-2012/2013), were compared using logistic mixed models. RESULTS: In multivariable-adjusted mixed models on up to 6635 adults (initial mean age 50 years; 70% male), healthy normal-weight adults experienced a decline in physical function of -3.68 (95% CI=-4.19, -3.16) score units per decade; healthy obese adults showed an additional -3.48 (-4.88, -2.08) units decline. Healthy normal-weight adults experienced a -0.49 (-1.11, 0.12) score unit worsening of bodily pain per decade; healthy obese adults had an additional -2.23 (-3.78, -0.69) units worsening. Healthy obesity versus healthy normal-weight conferred 3.39 (2.29, 5.02) times higher odds of mobility limitation and 3.75 (1.94, 7.24) times higher odds of disability. CONCLUSIONS: Our results suggest that obesity, even if metabolically healthy, accelerates age-related declines in functional ability and poses a threat to independence in older age.


Asunto(s)
Actividades Cotidianas , Evaluación de la Discapacidad , Salud , Obesidad/complicaciones , Obesidad/fisiopatología , Adulto , Índice de Masa Corporal , Dolor Crónico/etiología , Dolor Crónico/fisiopatología , Comorbilidad , Diabetes Mellitus Tipo 2/etiología , Diabetes Mellitus Tipo 2/fisiopatología , Dislipidemias/etiología , Dislipidemias/fisiopatología , Femenino , Encuestas Epidemiológicas , Humanos , Hipertensión/etiología , Hipertensión/fisiopatología , Resistencia a la Insulina , Masculino , Persona de Mediana Edad , Limitación de la Movilidad , Enfermedades Musculoesqueléticas/etiología , Enfermedades Musculoesqueléticas/fisiopatología , Obesidad/sangre , Factores de Riesgo , Factores de Tiempo , Caminata/fisiología
19.
Psychol Med ; 47(8): 1342-1356, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28122650

RESUMEN

BACKGROUND: Adverse psychosocial working environments characterized by job strain (the combination of high demands and low control at work) are associated with an increased risk of depressive symptoms among employees, but evidence on clinically diagnosed depression is scarce. We examined job strain as a risk factor for clinical depression. METHOD: We identified published cohort studies from a systematic literature search in PubMed and PsycNET and obtained 14 cohort studies with unpublished individual-level data from the Individual-Participant-Data Meta-analysis in Working Populations (IPD-Work) Consortium. Summary estimates of the association were obtained using random-effects models. Individual-level data analyses were based on a pre-published study protocol. RESULTS: We included six published studies with a total of 27 461 individuals and 914 incident cases of clinical depression. From unpublished datasets we included 120 221 individuals and 982 first episodes of hospital-treated clinical depression. Job strain was associated with an increased risk of clinical depression in both published [relative risk (RR) = 1.77, 95% confidence interval (CI) 1.47-2.13] and unpublished datasets (RR = 1.27, 95% CI 1.04-1.55). Further individual participant analyses showed a similar association across sociodemographic subgroups and after excluding individuals with baseline somatic disease. The association was unchanged when excluding individuals with baseline depressive symptoms (RR = 1.25, 95% CI 0.94-1.65), but attenuated on adjustment for a continuous depressive symptoms score (RR = 1.03, 95% CI 0.81-1.32). CONCLUSIONS: Job strain may precipitate clinical depression among employees. Future intervention studies should test whether job strain is a modifiable risk factor for depression.


Asunto(s)
Trastorno Depresivo/etiología , Estrés Laboral/complicaciones , Humanos
20.
J Hum Hypertens ; 31(6): 409-414, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28124683

RESUMEN

Few studies have examined objective physical activity in relation to 24 h ambulatory blood pressure (BP). We aimed to assess the association of 7-day objectively measured habitual physical activity with ambulatory BP in a sample of African and Caucasian school teachers (n=216, age 49.7 years) from the sympathetic activity and blood pressure in Africans prospective cohort study. Hypertension (ambulatory systolic BP⩾130 and/or diastolic BP⩾80 mm Hg) was prevalent in 53.2% of the sample, particularly in black Africans. The hypertensive group spent significantly more awake time in sedentary activity (51.5% vs 40.8% of waking hours, P=0.001), as well as doing less light- (34.1% vs 38.9%, P=0.043) and moderate-intensity (14.0% vs 19.7%, P=0.032) activities compared with normotensives, respectively. In covariate adjusted models, light-intensity activity time was associated with lower 24 h and daytime ambulatory systolic BP (ß=-0.15, 95% confidence interval (CI): -0.26, -0.05, P=0.004; ß=-0.14, CI: -0.24, -0.03, P=0.011) and diastolic BP (ß=-0.14, CI: -0.25, -0.03, P=0.015; ß=-0.13, CI: -0.24, -0.01, P=0.030), as well as resting systolic BP (ß=-0.13, CI: -0.24, -0.01, P=0.028). Sedentary time was associated only with 24 h systolic BP (ß=0.12; CI: 0.01, 0.22), which was largely driven by night-time recordings. Participants in the upper sedentary tertile were more likely to be 'non-dippers' (odds ratio=2.11, 95% CI: 0.99, 4.46, P=0.052) compared with the lowest sedentary tertile. There were no associations between moderate to vigorous activity and BP. In conclusion, objectively assessed daily light physical activity was associated with ambulatory BP in a mixed ethnic sample.


Asunto(s)
Monitoreo Ambulatorio de la Presión Arterial , Presión Sanguínea , Ritmo Circadiano , Ejercicio Físico , Hábitos , Hipertensión/fisiopatología , Maestros , Adulto , Femenino , Humanos , Hipertensión/diagnóstico , Hipertensión/etnología , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Valor Predictivo de las Pruebas , Prevalencia , Estudios Prospectivos , Factores de Riesgo , Conducta Sedentaria , Sudáfrica/epidemiología , Factores de Tiempo
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