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1.
Foods ; 11(2)2022 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-35053873

RESUMEN

The natural 20:80 whey:casein ratio in cow's milk (CM) for adults and infants is adjusted to reflect the 60:40 ratio of human milk, but the feeding and metabolic consequences of this adjustment have been understudied. In adult human subjects, the 60:40 CM differently affects glucose metabolism and hormone release than the 20:80 CM. In laboratory animals, whey-adapted goat's milk is consumed in larger quantities. It is unknown whether whey enhancement of CM would have similar consequences on appetite and whether it would affect feeding-relevant brain regulatory mechanisms. In this set of studies utilizing laboratory mice, we found that the 60:40 CM was consumed more avidly than the 20:80 control formulation by animals motivated to eat by energy deprivation and by palatability (in the absence of hunger) and that this hyperphagia stemmed from prolongation of the meal. Furthermore, in two-bottle choice paradigms, whey-adapted CM was preferred against the natural 20:80 milk. The intake of the whey-adapted CM induced neuronal activation (assessed through analysis of c-Fos expression in neurons) in brain sites promoting satiation, but importantly, this activation was less pronounced than after ingestion of the natural 20:80 whey:casein CM. Activation of hypothalamic neurons synthesizing anorexigenic neuropeptide oxytocin (OT) was also less robust after the 60:40 CM intake than after the 20:80 CM. Pharmacological blockade of the OT receptor in mice led to an increase in the consumption only of the 20:80 CM, thus, of the milk that induced greater activation of OT neurons. We conclude that the whey-adapted CM is overconsumed compared to the natural 20:80 CM and that this overconsumption is associated with weakened responsiveness of central networks involved in satiety signalling, including OT.

2.
Chem Res Toxicol ; 35(2): 125-139, 2022 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-35029374

RESUMEN

The wide application of nanomaterials in consumer and medical products has raised concerns about their potential adverse effects on human health. Thus, more and more biological assessments regarding the toxicity of nanomaterials have been performed. However, the different ways the evaluations were performed, such as the utilized assays, cell lines, and the differences of the produced nanoparticles, make it difficult for scientists to analyze and effectively compare toxicities of nanomaterials. Fortunately, machine learning has emerged as a powerful tool for the prediction of nanotoxicity based on the available data. Among different types of toxicity assessments, nanomaterial cytotoxicity was the focus here because of the high sensitivity of cytotoxicity assessment to different treatments without the need for complicated and time-consuming procedures. In this review, we summarized recent studies that focused on the development of machine learning models for prediction of cytotoxicity of nanomaterials. The goal was to provide insight into predicting potential nanomaterial toxicity and promoting the development of safe nanomaterials.


Asunto(s)
Aprendizaje Automático , Nanoestructuras/efectos adversos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Humanos
3.
Foods ; 10(3)2021 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-33808819

RESUMEN

Adjustment of protein content in milk formulations modifies protein and energy levels, ensures amino acid intake and affects satiety. The shift from the natural whey:casein ratio of ~20:80 in animal milk is oftentimes done to reflect the 60:40 ratio of human milk. Studies show that 20:80 versus 60:40 whey:casein milks differently affect glucose metabolism and hormone release; these data parallel animal model findings. It is unknown whether the adjustment from the 20:80 to 60:40 ratio affects appetite and brain processes related to food intake. In this set of studies, we focused on the impact of the 20:80 vs. 60:40 whey:casein content in milk on food intake and feeding-related brain processes in the adult organism. By utilising laboratory mice, we found that the 20:80 whey:casein milk formulation was consumed less avidly and was less preferred than the 60:40 formulation in short-term choice and no-choice feeding paradigms. The relative PCR analyses in the hypothalamus and brain stem revealed that the 20:80 whey:casein milk intake upregulated genes involved in early termination of feeding and in an interplay between reward and satiety, such as melanocortin 3 receptor (MC3R), oxytocin (OXT), proopiomelanocortin (POMC) and glucagon-like peptide-1 receptor (GLP1R). The 20:80 versus 60:40 whey:casein formulation intake differently affected brain neuronal activation (assessed through c-Fos, an immediate-early gene product) in the nucleus of the solitary tract, area postrema, ventromedial hypothalamic nucleus and supraoptic nucleus. We conclude that the shift from the 20:80 to 60:40 whey:casein ratio in milk affects short-term feeding and relevant brain processes.

4.
Vet Parasitol ; 288: 109295, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33171413

RESUMEN

The objective was to examine the effects of supplementary quebracho on control of coccidiosis and gastrointestinal nematodes in lambs and kids. In Exp. 1, naturally infected lambs weaned (87.8 ± 0.4 days of age; day 0) in January (winter) were blocked by sex and randomly assigned (n = 10/treatment) to receive supplement with or without 100 g/lamb of quebracho for 28 days. In Exp. 2, single or twin rearing ewes were randomly assigned into two groups, and naturally infected lambs were fed control (n = 28) or quebracho (100 g/lamb of quebracho tannins in feed; n = 27) between -28 and 21 days (weaning = day 0; 70.8 ± 0.1 days of age). In Exp. 3, weaned doe kids (57.6 ± 2.0 days of age) were randomly assigned to receive alfalfa (Medicago sativa) supplement with (n = 9) or without (n = 8) 50 g/kid quebracho or sericea lespedeza (Lespedeza cuneata) with quebracho (n = 8) for 21 days. Fecal oocyst count (FOC), nematode egg counts (FEC), fecal score, dag score (soiling around rear quarters), and blood packed cell volume (PCV) were determined every 7 days. Data were analyzed as repeated measures using mixed models. In Exp. 1, FOC decreased in quebracho-fed lambs (diet × time, P < 0.001) but FEC was similar between treatments during the feeding period (P = 0.19). Packed cell volume (P = 0.19) and fecal score (P = 0.42) were similar between groups. Quebracho-fed lambs had a greater dag score initially (diet × time, P = 0.02), but were similar by day 42 (P = 0.72). In Exp. 2, FOC remained low (P = 0.02), PCV tended to decrease (P = 0.06), but FEC increased on days 14 and 21 (diet × time; P < 0.001) in quebracho compared with control-fed lambs. Quebracho-fed lambs had lower fecal score (diet × time; P = 0.005) but higher dag score (diet × time; P < 0.001). In Exp. 3, FOC of kids fed quebracho (alfalfa or sericea lespedeza supplement) was lower than control (P < 0.001). Fecal score of kids fed sericea lespedeza compared with alfalfa were lower regardless of quebracho (P = 0.01). There were no differences among treatments for dag, FEC, PCV, or body weight (P> 0.10). Quebracho was effective in reducing FOC but not clinical signs of coccidiosis in both lambs and kids, and may not be highly digestible in lambs as it caused loose stools.


Asunto(s)
Anacardiaceae/química , Coccidiosis/veterinaria , Enfermedades de las Cabras/prevención & control , Infecciones por Nematodos/veterinaria , Enfermedades de las Ovejas/prevención & control , Taninos/metabolismo , Alimentación Animal/análisis , Animales , Coccidiosis/parasitología , Coccidiosis/prevención & control , Dieta/veterinaria , Suplementos Dietéticos/análisis , Relación Dosis-Respuesta a Droga , Eimeria/efectos de los fármacos , Tracto Gastrointestinal/parasitología , Enfermedades de las Cabras/parasitología , Cabras , Lespedeza/química , Medicago sativa/química , Nematodos/efectos de los fármacos , Infecciones por Nematodos/parasitología , Infecciones por Nematodos/prevención & control , Distribución Aleatoria , Ovinos , Enfermedades de las Ovejas/parasitología , Oveja Doméstica , Taninos/administración & dosificación , Taninos/química
5.
Curr Nutr Rep ; 8(2): 120-128, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30945139

RESUMEN

PURPOSE OF REVIEW: Eating behavior provides energy to ensure proper functioning of the organism. Reward aids in seeking foods that bring energy and pleasant taste, whose consumption is safe. As evidenced by the obesity "epidemic" which largely stems from overeating, reward becomes a detriment when palatable tastants are available in unlimited quantities. This review presents recent evidence on mechanisms underlying palatability-driven excessive consumption of sugar. RECENT FINDINGS: Appetite for sugar is propelled by changes in the morphology and activity of the reward system reminiscent of addiction. Sugar intake also shifts the hunger-satiety continuum, facilitating initiation of consumption in the absence of energy needs and maintenance of feeding despite ingestion of large food loads that endanger homeostasis. Ingestion of excessive amounts of sugar relies on triggering mechanisms that promote addictive-like behaviors, and on overriding neuroendocrine signals that protect internal milieu.


Asunto(s)
Conducta Adictiva , Conducta Alimentaria/fisiología , Recompensa , Azúcares/administración & dosificación , Animales , Apetito , Encéfalo/efectos de los fármacos , Ingestión de Alimentos , Humanos , Hiperfagia , Obesidad , Azúcares/efectos adversos , Gusto/fisiología
6.
Nutrients ; 11(4)2019 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-30925727

RESUMEN

Goat's (GM) and cow's milk (CM) are dietary alternatives with select health benefits shown in human and animal studies. Surprisingly, no systematic analysis of palatability or preference for GM vs. CM has been performed to date. Here, we present a comprehensive investigation of short-term intake and palatability profiles of GM and CM in laboratory mice and rats. We studied consumption in no-choice and choice scenarios, including meal microstructure, and by using isocaloric milks and milk-enriched solid diets. Feeding results are accompanied by qPCR data of relevant genes in the energy balance-related hypothalamus and brain stem, and in the nucleus accumbens, which regulates eating for palatability. We found that GM and CM are palatable to juvenile, adult, and aged rodents. Given a choice, animals prefer GM- to CM-based diets. Analysis of meal microstructure using licking patterns points to enhanced palatability of and, possibly, greater motivation toward GM over CM. Most profound changes in gene expression after GM vs. CM were associated with the brain systems driving consumption for reward. We conclude that, while both GM and CM are palatable, GM is preferred over CM by laboratory animals, and this preference is driven by central mechanisms controlling eating for pleasure.


Asunto(s)
Encéfalo/metabolismo , Bovinos , Conducta Alimentaria , Regulación de la Expresión Génica/efectos de los fármacos , Cabras , Leche , Envejecimiento/fisiología , Animales , Encéfalo/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratas , Ratas Sprague-Dawley , Especificidad de la Especie , Gusto
7.
Nanoscale ; 4(17): 5268-76, 2012 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-22833267

RESUMEN

Although coherent twin boundaries require little energy to form in nanoscale single crystals, their influence on properties can be dramatic. In recent years, some important steps forward have been made in understanding and controlling twinning processes at the nanoscale, making possible the fabrication of nanoengineered twinning superlattices in crystalline nanowires. These advances have opened new possibilities for properties and functionalities at the atomic and quantum scales by modulating twin densities. This article presents a brief overview of recent theoretical and experimental progress in growth mechanisms and promising properties of coherent twinning superlattice nanowires with special emphasis toward cubic systems in semiconductor and metallic materials. In particular, we show how nanoscale growth twins can considerably enhance bandgap engineering and mechanical behaviour in quasi-one-dimensional materials. Opportunities for future research in this emerging area are also discussed.

8.
Phys Chem Chem Phys ; 8(41): 4752-7, 2006 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-17043718

RESUMEN

High-quality ab initio potential energy curves are presented for the F(-)-Rg series (Rg = He-Rn). Calculations are performed at the CCSD(T) level of theory, employing d-aug-cc-pV5Z quality basis sets, with "small core" relativistic effective core potentials being used for Kr-Rn. The quality of the curves is judged by agreement with recent high-level calculations in the case of F(-)-He and F(-)-Ne and by excellent agreement with mobility data for the systems F(-)-Rg (Rg = He-Xe). Except for these recent high-level calculations on the two lightest systems, we are able to deduce that all other previous potentials for the whole set of these systems are inadequate. We also present spectroscopic information for the titular species, derived from our potential energy curves.


Asunto(s)
Flúor/química , Gases Nobles/química , Análisis Espectral/métodos , Algoritmos , Argón/química , Helio/química , Criptón/química , Conformación Molecular , Neón/química , Radón/química , Termodinámica , Xenón/química
9.
J Chem Phys ; 125(6): 64305, 2006 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-16942284

RESUMEN

High-level ab initio CCSD(T) calculations are performed in order to obtain accurate interaction potentials for the Br(-) anion interacting with each rare gas (Rg) atom. For the Rg atoms from He to Ar, two approaches are taken. The first one implements a relativistic core potential and an aug-cc-pVQZ basis set for bromine, an aug-cc-pV5Z basis set for Rg, and a set of bond functions placed at the midpoint of the Rg-Br distance. The second one uses the all-electron approximation with aug-cc-pV5Z bases further augmented by an extra diffuse function in each shell. Comparison reveals close similarity between both sets of results, so for Rg atoms from Kr to Rn only the second approach is exploited. Calculated potentials are assessed against the previous empirical, semiempirical, and ab initio potentials, and against available beam scattering data, zero electron kinetic energy spectroscopic data, and various sets of the measured ion mobilities and diffusion coefficients. This multiproperty analysis leads to the conclusion that the present potentials are consistently good for the whole series of Br(-)-Rg pairs over the whole range of internuclear distances covered.

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