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1.
Infection ; 52(4): 1449-1458, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38499828

RESUMEN

PURPOSE: In contrast to adults, immune protection against SARS-CoV-2 in children and adolescents with natural or hybrid immunity is still poorly understood. The aim of this study was to analyze different immune compartments in different age groups and whether humoral immune reactions correlate with a cellular immune response. METHODS: 72 children and adolescents with a preceding SARS-CoV-2 infection were recruited. 37 were vaccinated with an RNA vaccine (BNT162b2). Humoral immunity was analyzed 3-26 months (median 10 months) after infection by measuring Spike protein (S), nucleocapsid (NCP), and neutralizing antibodies (nAB). Cellular immunity was analyzed using a SARS-CoV-2-specific interferon-γ release assay (IGRA). RESULTS: All children and adolescents had S antibodies; titers were higher in those with hybrid immunity (14,900 BAU/ml vs. 2118 BAU/ml). NCP antibodies were detectable in > 90%. Neutralizing antibodies (nAB) were more frequently detected (90%) with higher titers (1914 RLU) in adolescents with hybrid immunity than in children with natural immunity (62.5%, 476 RLU). Children with natural immunity were less likely to have reactive IGRAs (43.8%) than adolescents with hybrid immunity (85%). The amount of interferon-γ released by T cells was comparable in natural and hybrid immunity. CONCLUSION: Spike antibodies are the most reliable markers to monitor an immune reaction against SARS-CoV-2. High antibody titers of spike antibodies and nAB correlated with cellular immunity, a phenomenon found only in adolescents with hybrid immunity. Hybrid immunity is associated with markedly higher antibody titers and a higher probability of a cellular immune response than a natural immunity.


Asunto(s)
Anticuerpos Neutralizantes , Anticuerpos Antivirales , COVID-19 , Inmunidad Celular , Inmunidad Humoral , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Humanos , COVID-19/inmunología , Adolescente , Niño , Masculino , Femenino , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/sangre , SARS-CoV-2/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Preescolar , Vacunas contra la COVID-19/inmunología , Inmunidad Innata , Proteínas de la Nucleocápside de Coronavirus/inmunología
2.
J Environ Manage ; 304: 114232, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-34933267

RESUMEN

Real-time measurements of particles in the 15-736 nm range have been obtained by a Scanning Mobility Particle Sizer to characterize the evolution of particle size distribution and new particle formation (NPF) events in an urban background area. The annual, weekly and diurnal variations of the modal (nucleation (Nnuc), Aitken (NAit) and accumulation (Nacc)) particle concentrations were characterised. The NAit and Nacc registered their maximums in cold months during rush hours, in the morning (0600-0900 UTC) and in the afternoon (1700-2000 UTC), while the maximums for Nnuc were reached in warm months during midday hours. NAit, Nacc and Ntotal showed a significant negative correlation with wind speed and a different relationship with the planetary boundary layer (PBL) height by periods. In the warm period, a positive significant correlation between PBL and Nnuc was registered, indicating that the higher dispersion promoted by a high PBL causes favourable conditions for the occurrence of NPF events (a low polluted atmosphere). NPF processes are one of the main sources of ultrafine particles (<100 nm) in the warm period. After a visual-based classification, 45 NPF events of type Ia (strong and with a good confidence level) were identified and analysed, occurring primarily between 1100 and 1500 UTC, mainly in spring and summer. In addition, a two-step method was developed for identifying NPF events: cluster analysis followed by discriminant analysis. The application of discriminant analysis to one of the clusters, grouping 93 days, enabled us to identify 55 of the 56 NPF events days included in the cluster. This method is a valuable tool for identifying NPF events quickly and effectively.


Asunto(s)
Contaminantes Atmosféricos , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Tamaño de la Partícula , Material Particulado/análisis , España
3.
Int J Behav Nutr Phys Act ; 18(1): 93, 2021 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-34243777

RESUMEN

BACKGROUND: Obesity is a serious issue, spanning all ages, and, in the U.S., disproportionately affects Latinos and African Americans. Understanding sleep, physical activity and dietary behaviors that may predict childhood obesity can help identify behavioral intervention targets. METHODS: Data were drawn from a U.S. cohort study of 323 Mexican American 8-10-year-old children and their mothers, who participated in a longitudinal study over a 2-year period. Measures were collected at baseline (BL; child mean age = 8.87, SD = 0.83), year 1 (FU1) and year 2 (FU2). Mothers reported on household income and acculturation at BL. Child height and weight were collected and BMI z-scores (BMIz) were calculated for weight status at BL, FU1, and FU2. Accelerometer-estimated sleep duration (hours) and moderate-to-vigorous physical activity (MVPA; minutes) were collected across 3 days at BL, FU1, and FU2. Two 24-h dietary recalls were performed at each time point; from these, average energy intake (EI, kcals/day) was estimated. Cross-lagged panel analysis was used to examine behavioral predictors on BMIz at each time point and across time. RESULTS: At BL and FU1, longer sleep duration (ß = - 0.22, p < 0.001; ß = - 0.17, p < 0.05, respectively) and greater MVPA (ß = - 0.13, p < 0.05; ß = - 0.20, p < 0.01, respectively) were concurrently related to lower BMIz. At FU2, longer sleep duration (ß = - 0.18, p < 0.01) was concurrently related to lower BMIz, whereas greater EI (ß = 0.16, p < 0.01) was related to higher BMIz. Longer sleep duration at BL predicted lower BMIz at FU1 (ß = - 0.05, p < 0.01). CONCLUSIONS: Longer sleep duration was concurrently related to lower weight status at each time point from ages 8-10 to 10-12. Higher MVPA was concurrently related to lower weight status in earlier childhood (ages 8-10 and 9-11) and higher EI was concurrently related to higher weight status toward the end of childhood (ages 10-12 years). Furthermore, longer sleep in earlier childhood was protective of children's lower weight status 1 year later. These findings suggest that sleep duration plays a consistent and protective role against childhood obesity; in addition, MVPA and healthy EI remain important independent factors for obtaining a healthy weight.


Asunto(s)
Ingestión de Energía/fisiología , Ejercicio Físico , Americanos Mexicanos , Sueño/fisiología , Índice de Masa Corporal , Niño , Estudios de Cohortes , Femenino , Humanos , Estudios Longitudinales , Masculino , Obesidad Infantil/etnología
4.
Nanotechnology ; 31(44): 445701, 2020 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-32668415

RESUMEN

Growing ultrathin nanogranular (NG) metallic films with continuously varying thickness is of great interest for studying regions of criticality and scaling behaviors in the vicinity of quantum phase transitions. In the present work, an ultrathin gold plasmonic NG film was grown on a sapphire substrate by RF magnetron sputtering with an intentional deposition gradient to create a linearly variable thickness ranging from 5 to 13 nm. The aim is to accurately study the electronic phase transition from the quantum tunneling regime to the metallic conduction one. The film structural characterization was performed by means of high-resolution transmission electron microscopy, atomic force microscopy, as well as x-ray diffraction and reflectivity techniques, which indicate the Volmer-Weber film growth mode. The optical and electrical measurements show a transition from dielectric-isolated gold NPs towards a continuous metallic network when t becomes larger than a critical value of tM = 7.8 nm. Our results show that the onset of the percolation region occurs when a localized surface plasma resonance transforms to display a Drude component, indicative of free charge carriers. We demonstrate that, by using a continuously varying thickness, criteria for metallicity can be unambiguously identified. The onset of metallicity is clearly distinguished by the Drude damping factor and by discontinuities in the plasma frequencies as functions of thickness.

5.
Am J Pathol ; 188(7): 1510-1516, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29684361

RESUMEN

The new paradigm of mutations in chromatin-modifying genes as driver events in the development of cancers has proved challenging to resolve the complex influences over disease phenotypes. In particular, impaired activities of members of the SWI/SNF chromatin remodeling complex have appeared in an increasing variety of tumors. Mutations in SNF5, a member of this ubiquitously expressed complex, arise in almost all cases of malignant rhabdoid tumor in the absence of additional genetic alterations. Therefore, we studied how activation of additional oncogenic pathways might shift the phenotype of disease driven by SNF5 loss. With the use of a genetically engineered mouse model, we examined the effects of a hypomorphic Vhl2B allele on disease phenotype, with a modest up-regulation of the hypoxia response pathway. Snf5+/-;Vhl2B/+ mice did not demonstrate a substantial difference in overall survival or a change in malignant rhabdoid tumor development. However, a high percentage of female mice showed complex hemorrhagic ovarian cysts, a phenotype rarely found in either parental mouse strain. These lesions also showed mosaic expression of SNF5 by immunohistochemistry. Therefore, our studies implicate that modest changes in angiogenic regulation interact with perturbations of SWI/SNF complex activity to modulate disease phenotypes.


Asunto(s)
Hemorragia/patología , Mutación , Quistes Ováricos/patología , Proteína SMARCB1/fisiología , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/fisiología , Animales , Femenino , Hemorragia/etiología , Hemorragia/metabolismo , Ratones , Ratones Noqueados , Quistes Ováricos/etiología , Quistes Ováricos/metabolismo , Fenotipo
6.
Nutr Metab Cardiovasc Dis ; 29(3): 268-278, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30648600

RESUMEN

BACKGROUND AND AIM: Increased ferritin levels have been widely associated with cardiovascular risk in adults. Whether ferritin levels and their changes during childhood are related to metabolic syndrome (MetS) at adolescence is unknown. We aimed to evaluate these associations using levels of ferritin at 5, 10 and 16 years and their linear increases and patterns of sustained increased levels across childhood. METHODS AND RESULTS: There were four samples evaluated according to non-missing values for study variables at each stage (5 years: 562; 10 years: 381; and 16 years: 567 children; non-missing values at any stage: 379). MetS risk was evaluated as a continuous Z score. Patterns of sustained increased ferritin (highest tertile) and slope of the change of ferritin per year across the follow-up were calculated. Ferritin levels in the highest versus lowest tertile at five and 16 years were significantly positively associated with MetS risk Z score at adolescence in boys and these associations were unaffected by adjustment for covariates. Having high, compared to low/moderate ferritin level at 2 or more time periods between 5 and 16 years was related to higher Mets Z-score in boys only [e.g. 5-10 years adjusted-beta (95 %CI):0.26 (0.05-0.48),P < 0.05]. In girls, ferritin Z score at 10 and 16 years was positively and independently associated with HOMA-IR Z score. In girls, the slope of ferritin per year in the highest tertile was positively associated with MetS risk Z-score [adjusted-beta (95 %CI):0.21 (0.05-0.38),P < 0.05]. CONCLUSIONS: Ferritin levels throughout childhood are positively related to cardiometabolic risk in adolescence, with associations varying by sex.


Asunto(s)
Ferritinas/sangre , Síndrome Metabólico/sangre , Adolescente , Factores de Edad , Biomarcadores/sangre , Niño , Preescolar , Chile/epidemiología , Femenino , Humanos , Estudios Longitudinales , Masculino , Síndrome Metabólico/diagnóstico , Síndrome Metabólico/epidemiología , Pronóstico , Medición de Riesgo , Factores de Riesgo , Factores Sexuales , Regulación hacia Arriba
7.
J Community Health ; 44(5): 874-880, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-30570695

RESUMEN

In reports among mostly, US, white, preschool and young school-age children eating in the absence of hunger (EAH) has been positively related to adiposity, with some support for a sex-specific relationship. There is considerable interest in EAH and obesity in populations at risk for obesity-like populations of countries that have undergone rapid development. We assessed adolescents (n = 679) after an overnight fast with anthropometry and an EAH paradigm beginning with an ad lib pre-load meal. Participants reported satisfaction and perceived ability to eat more food, and then proceeded to a room with freely available snacks where they were permitted to eat ad lib for 20 min. Adolescents were 16.8 years old, 52% male, and 14% with obesity. Median preload meal kcal consumption was 602 (IQR 474-746). Additional calories were consumed at the EAH snack by 47.6%. Among those who ate snack, 155 additional calories were consumed (IQR 78-283). Adolescents with obesity had 0.61 (95% CI 0.37-0.99) reduced odds of eating at the EAH snack adolescents without obesity. Adolescents with obesity were also less likely to eat above the median total calories compared to adolescents without obesity (OR = 0.59, 95% CI 0.36-0.96). A sex by obesity interaction term was not significant in any model. Obesity was related to eating behavior in our sample of Chilean adolescents, however not in the direction we hypothesized. Adolescents with obesity were less likely to eat additional calories in the EAH paradigm and ate fewer total calories compared to adolescents without obesity.


Asunto(s)
Conducta Alimentaria/fisiología , Hambre/fisiología , Obesidad , Adolescente , Chile , Ingestión de Energía , Femenino , Humanos , Masculino , Obesidad/epidemiología , Obesidad/fisiopatología , Bocadillos
8.
Proc Biol Sci ; 285(1870)2018 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-29321292

RESUMEN

Life-history traits such as spawning migrations and timing of reproduction are adaptations to specific environmental constraints and seasonal cycles in many organisms' annual routines. In this study we analyse how offspring fitness constrains spawning phenology in a large migratory apex predator, the Atlantic bluefin tuna. The reproductive schedule of Atlantic bluefin tuna varies between spawning sites, suggesting plasticity to local environmental conditions. Generally, temperature is considered to be the main constraint on tuna spawning phenology. We combine evidence from long-term field data, temperature-controlled rearing experiments on eggs and larvae, and a model of egg fitness, and show that Atlantic bluefin tuna do not spawn to optimize egg and larval temperature exposure. The timing of spawning leads to temperature exposure considerably lower than optimal at all spawning grounds across the Atlantic Ocean. The early spawning is constrained by thermal inhibition of egg hatching and larval growth rates, but some other factors must prevent later spawning. Matching offspring with ocean productivity and the prey peak might be an important driver for bluefin tuna spawning phenology. This finding is important for predictions of reproductive timing in future climate warming scenarios for bluefin tuna.


Asunto(s)
Migración Animal/fisiología , Calentamiento Global , Reproducción/fisiología , Temperatura , Atún/fisiología , Animales , Océano Atlántico , Clorofila , Femenino , Larva/crecimiento & desarrollo , Óvulo/crecimiento & desarrollo , Estaciones del Año , Factores de Tiempo , Zooplancton
9.
Phys Rev Lett ; 121(12): 128001, 2018 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-30296154

RESUMEN

We present a phenomenological model for granular suspension rheology in which particle interactions enter as constraints to relative particle motion. By considering constraints that are formed and released by stress respectively, we derive a range of experimental flow curves in a single treatment and predict singularities in viscosity and yield stress consistent with literature data. Fundamentally, we offer a generic description of suspension flow that is independent of bespoke microphysics.

10.
Anal Chem ; 89(21): 11491-11497, 2017 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-29023104

RESUMEN

One of the main limitations to the Pt-therapy in cancer is the development of associated drug resistance that can be associated with a significant reduction of the intracellular platinum concentration. Thus, intracellular Pt concentration could be considered as a biomarker of cisplatin resistance. In this work, an alternative method to address intracellular Pt concentration in individual cells is explored to permit the evaluation of different cell models and alternative therapies in a relatively fast way. For this aim, total Pt analysis in single cells has been implemented using a total consumption nebulizer coupled to inductively coupled plasma mass spectrometric detection (ICP-MS). The efficiency of the proposed device has been evaluated in combination with flow cytometry and turned out to be around 25% (cells entering the ICP-MS from the cells in suspension). Quantitative uptake studies of a nontoxic Tb-containing compound by individual cells were conducted and the results compared to those obtained by bulk analysis of the same cells. Both sets of data were statistically comparable. Thus, final application of the developed methodology to the comparative uptake of Pt-species in cisplatin resistant and sensitive cell lines (A2780cis and A2780) was conducted. The results obtained revealed the potential of this analytical strategy to differentiate between different cell lines of different sensitivity to the drug which might be of high medical interest.


Asunto(s)
Antineoplásicos/metabolismo , Cisplatino/metabolismo , Resistencia a Antineoplásicos , Espectrometría de Masas , Análisis de la Célula Individual/métodos , Antineoplásicos/farmacología , Transporte Biológico , Línea Celular Tumoral , Cisplatino/farmacología , Humanos , Análisis de la Célula Individual/instrumentación
11.
Osteoporos Int ; 28(10): 2823-2830, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28589419

RESUMEN

Little is known regarding the relationship between early life factors and bone mineral density (BMD). We found a positive association between breastfeeding for at least 6 months, without formula supplementation, and whole body adolescent BMD z-score. INTRODUCTION: The aim of the study is to assess the role of breastfeeding BF on adolescent bone mineral density (BMD) in a cohort prospectively followed since infancy. METHODS: We studied 679 participants from an infancy iron deficiency anemia preventive trial in Santiago, Chile, followed to adolescence. Breast and bottle feeding were ascertained weekly from 4 to 12 months. At 16 years, whole body BMD was assessed by DEXA. Using linear regression, we evaluated associations between BF duration and BF as the sole source of milk and adolescent BMD z-score, adjusting for possible infancy, adolescent, and background confounders. RESULTS: Mean birth weight and length were 3.5 (0.3) kg and 50.7 (1.6) cm. For at least 6 months, BF was the sole source of milk for 26.3% and with supplementation for 36.7%. For 37%, BF was provided for less than 6 months. Mean 16-year BMD z-score was 0.25 (1.0). Covariates included male sex, birth length, and gestational age. BF as the sole source of milk ≥6 months, compared to BF < 6 months, was associated with higher adolescent BMD z-score adjusting for covariates (ß = 0.29, p < 0.05). Mixed BF was not significantly related to adolescent BMD z-score (ß = 0.06, p = 0.47). For every 30 days of BF as the sole source of milk, adolescent BMD z-score increased by 0.03 (p = 0.01). CONCLUSION: BF without formula supplementation for at least 6 months was associated with higher adolescent BMD z-score and a suggestive trend in the same direction for BMD suggests that exclusivity and duration of BF may play a role in adolescent bone health.


Asunto(s)
Densidad Ósea/fisiología , Lactancia Materna , Absorciometría de Fotón , Adolescente , Factores de Edad , Envejecimiento/fisiología , Peso al Nacer/fisiología , Estatura/fisiología , Femenino , Estudios de Seguimiento , Edad Gestacional , Humanos , Lactante , Fenómenos Fisiológicos Nutricionales del Lactante/fisiología , Recién Nacido , Masculino , Estudios Prospectivos , Factores de Tiempo
12.
Pediatr Diabetes ; 18(8): 895-902, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28145023

RESUMEN

BACKGROUND: Increased cardiometabolic risk (CMR) is documented in obese and non-obese adolescents with low muscular fitness. However, the association of low muscle mass (LMM) with CMR, independent of weight status, has not been examined. We analyzed the relationship of LMM with CMR in adolescents, regardless of their weight status. MATERIALS AND METHODS: Observational study in 660 adolescents. BMI, waist circumference (WC), arterial blood pressures (ABP) were measured. Total fat mass (TFM), total lean tissue (TLT), and appendicular skeletal muscle mass (ASM) were estimated (DXA). Fasting lipid profile, glucose, and insulin were measured. HOMA-IR was estimated. Metabolic Syndrome (MetS) was diagnosed (AHA/NHLBI/IDF). ROC analysis was performed to find the optimal cutoffs of TLT percentage for MetS diagnosis. Values below these cutoffs defined LMM. ANCOVA examined the association of LMM with selected cardiometabolic biomarkers. RESULTS: In both sexes, TLT showed better sensitivity and specificity than ASM for MetS diagnosis. In males and females, TLT of 66.1% and 56.3%, respectively, were the optimal cutoff for MetS diagnosis. In the sample, 17.3% of males and 23.7% of females had LMM. In both sexes, adolescents with LMM had significantly higher values of WC, ABP, TG, TC/HDL, HOMA-IR, and MetS z-score than non-LMM participants. Adolescents with LMM, regardless nutritional status, had significantly increased values of MetS z-score, ABP, TG, TC/HDL-chol, and HOMA-IR than non-obese non-LMM adolescents. Adolescents having both obesity and LMM had the unhealthiest CMR profile. CONCLUSION: In adolescents, LMM was associated with higher CMR, regardless of nutritional status. In obese adolescents, LMM increased obesity-associated CMR.


Asunto(s)
Composición Corporal , Síndrome Metabólico/epidemiología , Músculo Esquelético , Estado Nutricional , Adolescente , Chile/epidemiología , Estudios de Cohortes , Estudios Transversales , Femenino , Humanos , Masculino , Síndrome Metabólico/etiología , Obesidad/complicaciones , Medición de Riesgo
13.
Nanotechnology ; 28(33): 335704, 2017 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-28644818

RESUMEN

Discontinuous multilayer (DML) thin films, which consist of nano-granular metals (NGMs) embedded in a dielectric matrix, have attracted significant interest as engineered plasmonic metamaterials. In this study, a systematic layer-by-layer deposition of three-dimensional sub-wavelength periodic plasmonic DML structures via the radio frequency sputtering of a composite target has been reported. The overall optical response of the DML films composed of Au-Al2O3 NGM homogenous layers, which are periodically sandwiched between two amorphous Al2O3 layers, are studied using reflection spectroscopic ellipsometry and transmission spectroscopy techniques. By applying the analytical optical approaches based on multiple Gaussian oscillators, ambient DML sub-wavelength structures have been successfully modeled. As a result, the effects of the size and shape of the Au nanoparticles as well as of the surrounding and interfacial media on their localized surface plasmon resonance (LSPR) are elucidated, and the related films thickness and effective optical constants are determined. Interestingly, during the examination of resonance frequencies and dielectric functions, the obtained DML structures exhibit unusual characteristics that are different from those of their NGM constituents due to the electromagnetic interactions of the NGM layers with the LSPR, which represent metamaterial features.

14.
Phys Chem Chem Phys ; 19(29): 18913-18923, 2017 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-28715032

RESUMEN

In this work, gold nanoparticles protected by the macrocycle cucurbit[7]uril were used as a catalyst in the reduction of the hazardous antimicrobial nitrofurantoin. 4-Nitrophenol was also employed as the substrate of the reduction for comparative purposes. The kinetic data were modeled to the Langmuir-Hinshelwood equation to know the affinities of the reactants for the surface and the real kinetic constants, a comparison at the molecular level that is made for the first time. From the results, it was observed that the adsorption of nitrofurantoin was stronger than that of 4-nitrophenol whilst the kinetic constant on the surface was higher for 4-nitrophenol than for nitrofurantoin. Additionally, shifts in the nanoparticle surface plasmon band permitted insights to be obtained into the adsorption rate and strength. The reaction induction times were also investigated and were highly dependent on the borohydride concentration and, due to the higher surface affinity of nitrofurantoin compared with 4-nitrophenol, an increase in nitrofurantoin concentration increased the induction time, while a lag phase was not observed for 4-nitrophenol.


Asunto(s)
Antiinfecciosos/química , Hidrocarburos Aromáticos con Puentes/química , Oro/química , Imidazoles/química , Nanopartículas del Metal/química , Nitrofurantoína/química , Adsorción , Catálisis , Cinética , Espectroscopía de Resonancia Magnética , Nitrofenoles/química , Oxidación-Reducción , Resonancia por Plasmón de Superficie
15.
Br Poult Sci ; 58(6): 739-747, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28929797

RESUMEN

1. The purpose of this work was to support decision-making in poultry farms by performing automatic early detection of anomalies in egg production. 2. Unprocessed data were collected from a commercial egg farm on a daily basis over 7 years. Records from a total of 24 flocks, each with approximately 20 000 laying hens, were studied. 3. Other similar works have required a prior feature extraction by a poultry expert, and this method is dependent on time and expert knowledge. 4. The present approach reduces the dependency on time and expert knowledge because of the automatic selection of relevant features and the use of artificial neural networks capable of cost-sensitive learning. 5. The optimum configuration of features and parameters in the proposed model was evaluated on unseen test data obtained by a repeated cross-validation technique. 6. The accuracy, sensitivity, specificity and positive predictive value are presented and discussed at 5 forecasting intervals. The accuracy of the proposed model was 0.9896 for the day before a problem occurs.


Asunto(s)
Crianza de Animales Domésticos/métodos , Pollos , Redes Neurales de la Computación , Óvulo , Animales , Femenino
16.
Faraday Discuss ; 191: 73-88, 2016 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-27442153

RESUMEN

We present a new class of organic-inorganic patchy particles for the efficient stabilization of Pickering foams and emulsions. Using solvent-based heterogeneous precipitation, we decorate inorganic silica particles with discrete domains of water insoluble plant protein (zein). By varying the extent of protein coverage on the silica surface, we tune the pH-dependent interactions of the particles and the interfaces. We observe an optimum foam stabilization, which is attributed to the creation of a slightly positive low effective surface potential from positively charged protein patches and the negatively charged silica surface. The effect of surface coverage on foam stability is in line with the predicted low interfacial potential of the patchy particles in water, which determines the energy of particle adsorption. In emulsions, the increase of the protein amount on the silica particles causes a progressive bridging of the oil droplets into a close-packing configuration due to gelation of the protein patches. Protein-based organic-inorganic surface heterogeneous particles represent a new versatile platform for the stabilization of fluid-in-fluid dispersions and as precursors for the assembly of advanced functional materials.

17.
Gerontology ; 62(4): 434-42, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26539838

RESUMEN

Age is the greatest risk factor for breast cancer, but the reasons underlying this association are unclear. While there is undeniably a genetic component to all cancers, the accumulation of mutations with age is insufficient to explain the age-dependent increase in breast cancer incidence. In this viewpoint, we propose a multilevel framework to better understand the respective roles played by somatic mutation, microenvironment, and epigenetics making women more susceptible to breast cancer with age. The process of aging is associated with gradual breast tissue changes that not only corrupt the tumor-suppressive activity of normal tissue but also impose age-specific epigenetic changes that alter gene expression, thus reinforcing cellular phenotypes that are associated with a continuum of age-related tissue microenvironments. The evidence discussed here suggests that while the riddle of whether epigenetics drives microenvironmental changes, or whether changes in the microenvironment alter heritable cellular memory has not been solved, a path has been cleared enabling functional analysis leading to the prediction of key nodes in the network that link the microenvironment with the epigenome. The hypothesis that the accumulation of somatic mutations with age drives the age-related increase in breast cancer incidence, if correct, has a somewhat nihilistic conclusion, namely that cancers will be impossible to avoid. Alternatively, if microenvironment-driven epigenetic changes are the key to explaining susceptibility to age-related breast cancers, then there is hope that primary prevention is possible because epigenomes are relatively malleable.


Asunto(s)
Envejecimiento/genética , Neoplasias de la Mama/genética , Mutación , Anciano , Envejecimiento/patología , Neoplasias de la Mama/patología , Epigénesis Genética , Femenino , Predisposición Genética a la Enfermedad , Humanos , Microambiente Tumoral/genética
18.
Child Care Health Dev ; 42(3): 343-50, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27059409

RESUMEN

BACKGROUND: Poor motor skills have been consistently linked with a higher body weight in childhood, but the causal direction of this association is not fully understood. This study investigated the temporal ordering between children's motor skills and weight status at 5 and 10 years. METHODS: Participants were 668 children (54% male) who were studied from infancy as part of an iron deficiency anaemia preventive trial and follow-up study in Santiago, Chile. All were healthy, full-term and weighing 3 kg or more at birth. Cross-lagged panel modelling was conducted to understand the temporal precedence between children's weight status and motor proficiency. Analyses also examined differences in gross and fine motor skills among healthy weight, overweight, and obese children. RESULTS: A higher BMI at 5 years contributed to declines in motor proficiency from 5 to 10 years. There was no support for the reverse, that is, poor motor skills at 5 years did not predict increases in relative weight from 5 to 10 years. Obesity at 5 years also predicted declines in motor proficiency. When compared with normal weight children, obese children had significantly poorer total and gross motor skills at both 5 and 10 years. Overweight children had poorer total and gross motor skills at 10 years only. The differences in total and gross motor skills among normal weight, overweight and obese children appear to increase with age. There were small differences in fine motor skill between obese and non-obese children at 5 years only. CONCLUSIONS: Obesity preceded declines in motor skills and not the reverse. Study findings suggest that early childhood obesity intervention efforts might help prevent declines in motor proficiency that, in turn, may positively impact children's physical activity and overall fitness levels.


Asunto(s)
Desarrollo Infantil/fisiología , Destreza Motora/fisiología , Obesidad Infantil/complicaciones , Desempeño Psicomotor/fisiología , Índice de Masa Corporal , Niño , Chile/epidemiología , Estudios Transversales , Femenino , Estudios de Seguimiento , Humanos , Masculino , Obesidad Infantil/epidemiología , Obesidad Infantil/fisiopatología , Prevalencia
19.
BMC Pulm Med ; 15: 92, 2015 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-26285574

RESUMEN

BACKGROUND: The FinnishIPF registry is a prospective, longitudinal national registry study on the epidemiology of idiopathic pulmonary fibrosis (IPF). It was designed to describe the characteristics, management and prognosis of prevalent and incident IPF patients. The study was initiated in 2012. METHODS: We present here results limited to five university hospitals. Patients with IPF were screened from hospital registries using ICD-10 diagnosis codes J84.1 and J84.9. All patients who gave informed consent were included and evaluated using novel diagnostic criteria. Point prevalence on the 31(st) of December in 2012 was calculated using the reported population in each university hospital city as the denominator. RESULTS: Patients with ICD-10 codes J84.1 and J84.9 yielded a heterogeneous group - on the basis of patient records assessed by pulmonologists only 20-30 % of the cases were IPF. After clinical, radiological and histological re-evaluation 111 of 123 (90 %) of patients fulfilled the clinical criteria of IPF. The estimated prevalence of IPF was 8.6 cases/100 000. 60.4 % were men. Forty four percent of the patients were never-smokers. At diagnosis, the patients' mean age was 73.5 years and mean FVC was 80.4 % and DLCO 57.3 % of predicted. CONCLUSIONS: Our results suggest that hospital registries are inaccurate for epidemiological studies unless patients are carefully re-evaluated. IPF is diagnosed in Finland at a stage when lung function is still quite well preserved. Smoking in patients with IPF was less common than in previous reports.


Asunto(s)
Fibrosis Pulmonar Idiopática/diagnóstico , Registros Médicos , Sistema de Registros , Anciano , Exactitud de los Datos , Femenino , Finlandia/epidemiología , Estudios de Seguimiento , Hospitales Universitarios , Humanos , Fibrosis Pulmonar Idiopática/epidemiología , Incidencia , Masculino , Prevalencia , Pronóstico , Estudios Prospectivos , Tomografía Computarizada por Rayos X
20.
Int J Obes (Lond) ; 38(4): 552-7, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24145926

RESUMEN

OBJECTIVE: To determine patterns of satiety responsiveness and its relationship to eating in the absence of hunger (EAH), in a cohort of adolescents. We also assessed whether sex, body mass index and duration of breastfeeding, during infancy, predicted satiety responsiveness and eating behavior at 16 years. METHODS: Adolescents (n=576) from a longitudinal cohort, which began as an iron deficiency anemia preventive trial, participated in an unlimited breakfast after an overnight fast, and reported satiety response on a visual analog scale after the meal, followed by an EAH procedure. Height, weight and body composition were measured before breakfast. Latent profile analysis generated profiles that captured individual differences in satiety responsiveness. Multivariable regressions, adjusted for potential confounders, evaluated the association between: (1) satiety responsiveness and EAH, and (2) breastfeeding in infancy, satiety responsiveness and EAH in adolescence. RESULTS: Participants were on average 16.7-year old, 48% female, 37% overweight/obese and 76% were breastfed as the sole source of milk for <6 months. We found three latent profiles of satiety responsiveness: 1: 'responsive' (49%); 2: 'not responsive' (41%); 3: 'still hungry' (10%). Participants in the 'not responsive' or 'still hungry' profile were more likely to eat during the EAH procedure (odds ratio (OR)=2.5, 95% confidence interval (CI)=1.8-3.6). Being breastfed for <6 months was related to higher odds of being in the 'not responsive' or 'still hungry' profile (OR=1.8, 95% CI=1.2-2.6) and EAH (OR=2.2, 95% CI=1.4-3.3). Satiety responsiveness was not influenced by sex and overweight/obesity. CONCLUSION: After an ad libitum meal, we found varied satiety responses, which related to EAH. Furthermore, shorter breastfeeding duration was associated with poorer satiety response and higher consumption during an EAH procedure. Understanding if breastfeeding influences the development of satiety responsiveness and eating behavior may be important in an era characterized by abundant calorie-dense foods and a plethora of environmental cues promoting consumption.


Asunto(s)
Conducta del Adolescente/psicología , Regulación del Apetito , Lactancia Materna , Conducta Alimentaria/psicología , Obesidad Infantil/psicología , Respuesta de Saciedad , Adolescente , Apetito , Índice de Masa Corporal , Chile/epidemiología , Ingestión de Alimentos , Ingestión de Energía , Femenino , Humanos , Hambre , Estudios Longitudinales , Masculino , Comidas , Obesidad Infantil/etiología
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