Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 100
Filtrar
Más filtros

Intervalo de año de publicación
1.
Hum Brain Mapp ; 45(4): e26618, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38414286

RESUMEN

BACKGROUND: Age-related cognitive decline is linked to changes in the brain, particularly the deterioration of white matter (WM) microstructure that accelerates after the age of 60. WM deterioration is associated with mild cognitive impairment and dementia, but the origin and role of white matter signal abnormalities (WMSA) seen in standard MRI remain debated due to their heterogeneity. This study explores the potential of single-shell 3-tissue constrained spherical deconvolution (SS3T-CSD), a novel technique that models diffusion data in terms of gray matter (TG ), white matter (Tw ), and cerebrospinal fluid (TC ), to differentiate WMSA from normal-appearing white matter and better understand the interplay between changes in WM microstructure and decline in cognition. METHODS: A total of 189 individuals from the GENIC cohort were included. MRI data, including T1-weighted and diffusion images, were obtained. Preprocessing steps were performed on the diffusion MRI data, followed by the SS3T-CSD. WMSA were segmented using FreeSurfer. Statistical analyses were conducted to assess the association between age, WMSA volume, 3-tissue signal fractions (Tw , TG , and TC ), and neuropsychological variables. RESULTS: Participants above 60 years old showed worse cognitive performance and processing speed compared to those below 60 (p < .001). Age was negatively associated with Tw in normal-appearing white matter (p < .001) and positively associated with TG in both WMSA (p < .01) and normal-appearing white matter (p < .001). Age was also significantly associated with WMSA volume (p < .001). Higher processing speed was associated with lower Tw and higher TG , in normal-appearing white matter (p < .01 and p < .001, respectively), as well as increased WMSA volume (p < .001). Similarly, lower MMSE scores correlated with lower Tw and higher TG in normal-appearing white matter (p < .05). High cholesterol and hypertension were associated with higher WMSA volume (p < .05). CONCLUSION: The microstructural heterogeneity within normal-appearing white matter and WMSA is associated with increasing age and cognitive variation, in cognitively unimpaired individuals. Furthermore, the 3-tissue signal fractions are more specific to potential white matter alterations than conventional MRI measures such as WMSA volume. These findings also support the view that the WMSA volumes may be more influenced by vascular risk factors than the 3-tissue metrics. Finally, the 3-tissue metrics were able to capture associations with cognitive tests and therefore capable of capturing subtle pathological changes in the brain in individuals who are still within the normal range of cognitive performance.


Asunto(s)
Sustancia Blanca , Humanos , Persona de Mediana Edad , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Imagen de Difusión por Resonancia Magnética , Envejecimiento/patología , Cognición , Imagen por Resonancia Magnética
2.
Hum Brain Mapp ; 44(4): 1289-1308, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36468536

RESUMEN

Predicting brain aging can help in the early detection and prognosis of neurodegenerative diseases. Longitudinal cohorts of healthy subjects scanned through magnetic resonance imaging (MRI) have been essential to understand the structural brain changes due to aging. However, these cohorts suffer from missing data due to logistic issues in the recruitment of subjects. This paper proposes a methodology for filling up missing data in longitudinal cohorts with anatomically plausible images that capture the subject-specific aging process. The proposed methodology is developed within the framework of diffeomorphic registration. First, two novel modules are introduced within Synthmorph, a fast, state-of-the-art deep learning-based diffeomorphic registration method, to simulate the aging process between the first and last available MRI scan for each subject in three-dimensional (3D). The use of image registration also makes the generated images plausible by construction. Second, we used six image similarity measurements to rearrange the generated images to the specific age range. Finally, we estimated the age of every generated image by using the assumption of linear brain decay in healthy subjects. The methodology was evaluated on 2662 T1-weighted MRI scans from 796 healthy participants from 3 different longitudinal cohorts: Alzheimer's Disease Neuroimaging Initiative, Open Access Series of Imaging Studies-3, and Group of Neuropsychological Studies of the Canary Islands (GENIC). In total, we generated 7548 images to simulate the access of a scan per subject every 6 months in these cohorts. We evaluated the quality of the synthetic images using six quantitative measurements and a qualitative assessment by an experienced neuroradiologist with state-of-the-art results. The assumption of linear brain decay was accurate in these cohorts (R2  ∈ [.924, .940]). The experimental results show that the proposed methodology can produce anatomically plausible aging predictions that can be used to enhance longitudinal datasets. Compared to deep learning-based generative methods, diffeomorphic registration is more likely to preserve the anatomy of the different structures of the brain, which makes it more appropriate for its use in clinical applications. The proposed methodology is able to efficiently simulate anatomically plausible 3D MRI scans of brain aging of healthy subjects from two images scanned at two different time points.


Asunto(s)
Encéfalo , Imagenología Tridimensional , Humanos , Imagenología Tridimensional/métodos , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Imagen por Resonancia Magnética/métodos , Neuroimagen/métodos , Envejecimiento , Procesamiento de Imagen Asistido por Computador/métodos , Algoritmos
3.
J Int Neuropsychol Soc ; 29(7): 632-640, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36226685

RESUMEN

OBJECTIVE: Parkinson's disease patients with subjective cognitive decline (PD-SCD) and mild cognitive impairment (PD-MCI) have an increased risk of dementia (PDD). Thus, the identification of early cognitive changes that can be useful predictors of PDD is a highly relevant challenge. Posterior cortically based functions, including linguistic processes, have been associated with PDD. However, investigations that have focused on linguistic functions in PD-MCI are scarce and none of them include PD-SCD patients. Our aim was to study language performance in PD-SCD and PD-MCI. Moreover, language subcomponents were considered as predictors of PDD. METHOD: Forty-six PD patients and twenty controls were evaluated with a neuropsychological protocol. Patients were classified as PD-SCD and PD-MCI. Language production and comprehension was assessed. Follow-up assessment was conducted to a mean of 7.5 years after the baseline. RESULTS: PD-MCI patients showed a poor performance in naming (actions and nouns), action generation, anaphora resolution and sentence comprehension (with and without center-embedded relative clause). PD-SCD showed a poor performance in action naming and action generation. Deficit in action naming was an independent risk factor for PDD during the follow-up. Moreover, the combination of deficit in action words and sentence comprehension without a center-embedded relative clause was associated with a greater risk. CONCLUSIONS: The results are of relevance because they suggest that a specific pattern of linguistic dysfunctions, that can be present even in the early stages of the disease, can predict future dementia, reinforcing the importance of advancing in the knowledge of linguistic dysfunctions in predementia stages of PD.


Asunto(s)
Disfunción Cognitiva , Demencia , Enfermedad de Parkinson , Humanos , Pruebas Neuropsicológicas , Disfunción Cognitiva/etiología , Disfunción Cognitiva/complicaciones , Demencia/complicaciones , Demencia/psicología , Lingüística
4.
Molecules ; 28(18)2023 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-37764385

RESUMEN

With a characteristic flavour and aroma, "Maçã de Alcobaça" are apples produced in the western region of the mainland of Portugal. Given the known influence of pre-harvest cultural techniques and post-harvest conservation methods on fruit quality, this work evaluated the effect of cultural factors and conservation methods on the volatile profile of 'Gala' apples. Tests were carried out during four seasons (2018 to 2021) in two 'Gala' apple orchards (F and S) maintained with different irrigation rates and nitrogen fertilisation [normal irrigation and normal nitrogen (Control, NINN), normal irrigation and excess nitrogen (NIEN), excess irrigation and normal nitrogen (EINN), excess irrigation and excess nitrogen (EIEN)], and under three storage conditions [Controlled Atmosphere + 1-methylcyclopropene (CA+1-MCP), Dynamic Controlled Atmosphere (DCA) and DCA+1-MCP]. The intact fruit volatiles were isolated by headspace solid-phase microextraction (HS-SPME) and analysed by Gas Chromatography with Flame Ionisation Detection and Gas Chromatography-Mass Spectrometry at harvest (T0) and after 8 months of storage (T8). HS-SPME volatiles from 'Gala' apples, obtained at T0 in control conditions, were characterised by trans,trans-α-farnesene dominance (36-69%), followed by hexyl acetate (5-23%) and hexyl hexanoate (3-9%). The four irrigation and nitrogen treatments did not evidence main changes in the apple volatile profile. Instead, storage conditions changed the ratio between compounds; previously undetected compounds attained high percentages and decreased the intensity of the dominant compounds in the control conditions. Although all storage conditions tested changed the volatile profile and emanation intensity, the effect was more accentuated in storage for 8 months with DCA+1-MCP.

5.
Trop Anim Health Prod ; 55(1): 58, 2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36719488

RESUMEN

Progesterone (P4) is a steroid hormone that has a regulatory role in the female reproductive system. Studies on the effects of injectable progesterone on ewes are scarce, mainly related to their reproductive responses in the breeding season. This study aimed to compare reproductive performance and serum P4 concentration using injectable or intravaginal P4 in ewes. Two hundred and forty and eight Santa Inês x Dorper ewes (BW; 52.67 ± 11.76 kg; mean ± SE), body condition score (BCS; 2.5 ± 0.8; scale of 1-5), were distributed in four treatments: (i) Control: without administration of P4; (ii) CIDR: intravaginal implantation of 330 mg of P4 for 7 days; (iii) 1P4: 15 mg of P4 intramuscular (IM); and (iv) 2P4I: 30 mg of P4 IM. The first 18 days of breeding season were considered the synchronization period. Except for ewes in the control group, all other ewes received 263 µg IM of cloprostenol sodium for lysis of eventual CL at 24 h before the P4 treatment. After the synchronization period, all ewes were kept together with males for extra 28 days in the breeding season. At the beginning of breeding season, 90% of the ewes had serum P4 concentration less than 1 ng/mL. The estrus rate was greater (P < 0.01) in ewes on the CIDR treatment, with similar estrus rate among the other treatments. The P4 implant was able to keep blood P4 concentration greater than 1 ng/mL in ewes that received an implant of P4 during the 7 days. After implant removal, there was a great increase in the estrus manifestation on ewes in the CIDR treatment, leading to an increase in pregnancy rate at the beginning of breeding season. The current study demonstrated that ewes that received an intramuscular injection of 15 or 30 mg of P4 had similar reproductive performance than ewes that did not receive any P4 intramuscular injection. However, when ewes were implanted with P4 (CIDR), these animals had an increase in estrus manifestation, leading to greater pregnancy earlier during the breeding season.


Asunto(s)
Sincronización del Estro , Progesterona , Embarazo , Masculino , Ovinos , Femenino , Animales , Estaciones del Año , Reproducción , Estro , Administración Intravaginal
6.
Trop Anim Health Prod ; 55(3): 230, 2023 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-37256457

RESUMEN

The early attainment of puberty in heifers is essential for the profitability of the cow-calf farm. This study aimed to evaluate the impact of juvenile average daily gain (ADG) and sire's expected progeny difference (EPD) on puberty of crossbred beef heifers. Sixty Angus × Nellore heifers early weaned (age = 102 ± 4.3 d; initial BW = 103 ± 4.7 kg) were used in a 2 × 2 factorial arrangement. The factor 1 was the sire's EPD for scrotal circumference, in which heifers born from sires with positive EPD were considered precocious (P), and heifers born from sires with negative EPD were considered non-precocious (NP). The factor 2 was the high (HG; ADG = 0.9 kg; ad libitum) and medium ADG (MG; ADG = 0.7 kg) from 3rd to 7th month of age (1st phase). After 1st phase until puberty, all heifers were fed ad libitum (2nd phase). Statistical analysis was performed by SAS. There was an interaction between factors for DMI in the 1st phase (P = 0.02), which PHG heifers had higher DMI than NPHG. There was no effect on puberty rate, BW, age and BCS at puberty comparing HG vs. MG. However, favorable sires' EPD for scrotal circumference induced a higher proportion of puberty (P 87% vs. NP 59%) at 15 months of age. Thus, the ADG in juvenile age did not affect puberty rate, but sires with positive EPD increased puberty rate of Angus × Nellore heifers in heifers fed a high gain diet.


Asunto(s)
Alimentación Animal , Maduración Sexual , Bovinos , Animales , Femenino , Alimentación Animal/análisis , Dieta/veterinaria , Destete
7.
Cereb Cortex ; 31(8): 3832-3845, 2021 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-33866353

RESUMEN

Elucidating compensatory mechanisms underpinning phonemic fluency (PF) may help to minimize its decline due to normal aging or neurodegenerative diseases. We investigated cortical brain networks potentially underpinning compensation of age-related differences in PF. Using graph theory, we constructed networks from measures of thickness for PF, semantic, and executive-visuospatial cortical networks. A total of 267 cognitively healthy individuals were divided into younger age (YA, 38-58 years) and older age (OA, 59-79 years) groups with low performance (LP) and high performance (HP) in PF: YA-LP, YA-HP, OA-LP, OA-HP. We found that the same pattern of reduced efficiency and increased transitivity was associated with both HP (compensation) and OA (aberrant network organization) in the PF and semantic cortical networks. When compared with the OA-LP group, the higher PF performance in the OA-HP group was associated with more segregated PF and semantic cortical networks, greater participation of frontal nodes, and stronger correlations within the PF cortical network. We conclude that more segregated cortical networks with strong involvement of frontal nodes seemed to allow older adults to maintain their high PF performance. Nodal analyses and measures of strength were helpful to disentangle compensation from the aberrant network organization associated with OA.


Asunto(s)
Envejecimiento/fisiología , Corteza Cerebral/fisiología , Red Nerviosa/fisiología , Conducta Verbal/fisiología , Adulto , Anciano , Mapeo Encefálico , Función Ejecutiva , Femenino , Lóbulo Frontal/fisiología , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Desempeño Psicomotor/fisiología
8.
Trop Anim Health Prod ; 54(5): 258, 2022 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-35948838

RESUMEN

This study aimed to evaluate the reproductive performance of ewes submitted to timed AI protocol with 7 (D7) or 9 (D9) days of progesterone. A total of 220 crossbred ewes (Doper × Santa Ines) were distributed in the treatments according to body weight (52.67 ± 11.76 kg), body condition score (2.5 ± 0.8; scale of 1-5), and the female category (multiparous, nulliparous and primiparous). Ewes received an intravaginal device of 0.3 g of progesterone (CIDR® Easy breed) on day 0, keeping in ewes for 7 or 9 days, which were the experimental treatments. At the time of P4 withdrawal, ewes received 300 IU of eCG (Novormon®) and 6.70 mg of dinoprost tromethamine (Lutalyse®). Insemination by laparoscopy was performed between 46 and 59 h after device removal, lasting from 1 to 5 min/ewe, which did not differ between protocols. The estrus detection rate was higher in the 9-day protocol compared to the 7-day protocol (82% and 65%, respectively, P = 0.0096). However, the 7-day protocol tended to increase pregnancy rate on the TAI compared to the 9-day protocol (45% and 33%, respectively, P = 0.09). The plasma concentration of progesterone at device removal was higher in the 7-day protocol than in the 9-day protocol (2.35 and 1.22 ng/mL, respectively, P = 0.04). We conclude that reducing the length of the estrus synchronization protocol to 7 days is recommended, which improved the reproductive response in ewes.


Asunto(s)
Inseminación Artificial , Progesterona , Animales , Dinoprost/farmacología , Detección del Estro , Sincronización del Estro , Femenino , Hormona Liberadora de Gonadotropina/farmacología , Inseminación Artificial/métodos , Inseminación Artificial/veterinaria , Embarazo , Índice de Embarazo , Ovinos
9.
J Int Neuropsychol Soc ; 27(7): 722-732, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33303048

RESUMEN

OBJECTIVE: Subjective cognitive decline (SCD) and mild cognitive impairment (MCI) in Parkinson's disease (PD) are considered as the risk factors for dementia (PDD). Posterior cortically based functions, such as visuospatial and visuoperceptual (VS-VP) processing, have been described as predictors of PDD. However, no investigations have focused on the qualitative analysis of the Judgment of Line Orientation Test (JLOT) and the Facial Recognition Test (FRT) in PD-SCD and PD-MCI. The aim of this work was to study the VS-VP errors in JLOT and FRT. Moreover, these variables are considered as predictors of PDD. METHOD: Forty-two PD patients and 19 controls were evaluated with a neuropsychological protocol. Patients were classified as PD-SCD and PD-MCI. Analyses of errors were conducted following the procedure described by Ska, Poissant, and Joanette (1990). Follow-up assessment was conducted to a mean of 7.5 years after the baseline. RESULTS: PD-MCI patients showed a poor performance in JLOT and FRT total score and made a greater proportion of severe intraquadrant (QO2) and interquadrant errors (IQO). PD-SCD showed a poor performance in FRT and made mild errors in JLOT. PD-MCI and QO2/IQO errors were independent risk factors for PDD during the follow-up. Moreover, the combination of both PD-MCI diagnosis and QO2/IQO errors was associated with a greater risk. CONCLUSIONS: PD-MCI patients presented a greater alteration in VS-VP processing observable by the presence of severe misjudgments. PD-SCD patients also showed mild difficulties in VS-SP functions. Finally, QO2/IQO errors in PD-MCI are a useful predictor of PDD, more than PD-MCI diagnosis alone.


Asunto(s)
Disfunción Cognitiva , Demencia , Enfermedad de Parkinson , Disfunción Cognitiva/etiología , Demencia/complicaciones , Humanos , Pruebas Neuropsicológicas , Enfermedad de Parkinson/complicaciones , Factores de Riesgo
10.
BMC Bioinformatics ; 21(1): 275, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-32611389

RESUMEN

BACKGROUND: Protein engineering has many applications for industry, such as the development of new drugs, vaccines, treatment therapies, food, and biofuel production. A common way to engineer a protein is to perform mutations in functionally essential residues to optimize their function. However, the discovery of beneficial mutations for proteins is a complex task, with a time-consuming and high cost for experimental validation. Hence, computational approaches have been used to propose new insights for experiments narrowing the search space and reducing the costs. RESULTS: In this study, we developed Proteus (an acronym for Protein Engineering Supporter), a new algorithm for proposing mutation pairs in a target 3D structure. These suggestions are based on contacts observed in other known structures from Protein Data Bank (PDB). Proteus' basic assumption is that if a non-interacting pair of amino acid residues in the target structure is exchanged to an interacting pair, this could enhance protein stability. This trade is only allowed if the main-chain conformation of the residues involved in the contact is conserved. Furthermore, no steric impediment is expected between the proposed mutations and the surrounding protein atoms. To evaluate Proteus, we performed two case studies with proteins of industrial interests. In the first case study, we evaluated if the mutations suggested by Proteus for four protein structures enhance the number of inter-residue contacts. Our results suggest that most mutations proposed by Proteus increase the number of interactions into the protein. In the second case study, we used Proteus to suggest mutations for a lysozyme protein. Then, we compared Proteus' outcomes to mutations with available experimental evidence reported in the ProTherm database. Four mutations, in which our results agree with the experimental data, were found. This could be initial evidence that changes in the side-chain of some residues do not cause disturbances that harm protein structure stability. CONCLUSION: We believe that Proteus could be used combined with other methods to give new insights into the rational development of engineered proteins. Proteus user-friendly web-based tool is available at < http://proteus.dcc.ufmg.br >.


Asunto(s)
Proteínas/química , Interfaz Usuario-Computador , Algoritmos , Bases de Datos de Proteínas , Muramidasa/química , Muramidasa/genética , Muramidasa/metabolismo , Mutagénesis , Ingeniería de Proteínas/métodos , Estructura Terciaria de Proteína , Proteínas/genética , Proteínas/metabolismo
11.
Neuroimage ; 211: 116607, 2020 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-32035186

RESUMEN

The integrity of the cholinergic system plays a central role in cognitive decline both in normal aging and neurological disorders including Alzheimer's disease and vascular cognitive impairment. Most of the previous neuroimaging research has focused on the integrity of the cholinergic basal forebrain, or its sub-region the nucleus basalis of Meynert (NBM). Tractography using diffusion tensor imaging data may enable modelling of the NBM white matter projections. We investigated the contribution of NBM volume, NBM white matter projections, small vessel disease (SVD), and age to performance in attention and memory in 262 cognitively normal individuals (39-77 years of age, 53% female). We developed a multimodal MRI pipeline for NBM segmentation and diffusion-based tracking of NBM white matter projections, and computed white matter hypointensities (WM-hypo) as a marker of SVD. We successfully tracked pathways that closely resemble the spatial layout of the cholinergic system as seen in previous post-mortem and DTI tractography studies. We found that high WM-hypo load was associated with older age, male sex, and lower performance in attention and memory. A high WM-hypo load was also associated with lower integrity of the cholinergic system above and beyond the effect of age. In a multivariate model, age and integrity of NBM white matter projections were stronger contributors than WM-hypo load and NBM volume to performance in attention and memory. We conclude that the integrity of NBM white matter projections plays a fundamental role in cognitive aging. This and other modern neuroimaging methods offer new opportunities to re-evaluate the cholinergic hypothesis of cognitive aging.


Asunto(s)
Envejecimiento/fisiología , Atención/fisiología , Prosencéfalo Basal/anatomía & histología , Núcleo Basal de Meynert/anatomía & histología , Imagen de Difusión Tensora , Memoria/fisiología , Sustancia Blanca/anatomía & histología , Adulto , Factores de Edad , Anciano , Prosencéfalo Basal/diagnóstico por imagen , Núcleo Basal de Meynert/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Vías Nerviosas/anatomía & histología , Vías Nerviosas/diagnóstico por imagen , Factores Sexuales , Sustancia Blanca/diagnóstico por imagen
12.
Chem Biodivers ; 17(3): e1900669, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31984627

RESUMEN

1,8-Cineole is the main volatile produced by Thymus albicans Hoffmanns. & Link 1,8-cineole chemotype. To understand the contribution of distinct plant organs to the high 1,8-cineole production, trichome morphology and density, as well as emitted volatiles and transcriptional expression of the 1,8-cineole synthase (CIN) gene were determined separately for T. albicans leaves, bracts, calyx, corolla and inflorescences. Scanning electron microscopy (SEM) and stereoscope microscopy observations showed the highest peltate trichome density in leaves and bracts, significantly distinct from calyx and corolla. T. albicans volatiles were collected by solid phase micro extraction (SPME) and analyzed by gas chromatography-mass spectrometry (GC/MS) and by GC for component identification and quantification, respectively. Of the 23 components identified, 1,8-cineole was the dominant volatile (57-93 %) in all T. albicans plant organs. The relative amounts of emitted volatiles clearly separated vegetative from reproductive organs. Gene expression of CIN was assigned to all organs analyzed and was consistent with the relatively high emission of 1,8-cineole in leaves and bracts. Further studies will be required to analyze monoterpenoid biosynthesis by each type of glandular trichome.


Asunto(s)
Liasas de Carbono-Carbono/genética , Eucaliptol/metabolismo , Genitales/química , Aceites Volátiles/metabolismo , Thymus (Planta)/metabolismo , Liasas de Carbono-Carbono/metabolismo , Eucaliptol/química , Flores/química , Flores/metabolismo , Frutas/química , Frutas/metabolismo , Genitales/metabolismo , Aceites Volátiles/química , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Thymus (Planta)/química
13.
Trop Anim Health Prod ; 52(1): 373-378, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31372882

RESUMEN

The objectives were to evaluate the effects of two non-fibrous carbohydrate sources and the rate of body weight gain on puberty status in ewe lambs. Sixty ewe lambs (½ Dorper × ½ Santa Ines) with an initial body weight of 25.1 ± 4.1 kg and 102.8 ± 1.5 days old were distributed in a randomized complete block design with 10 blocks and 3 treatments. The trial lasted 119 days, in which performance was evaluated on days 28, 56, 84, and 119, and puberty status was every week evaluated by progesterone concentration. The treatments were characterized by the inclusion of different carbohydrate sources in the diets in order for ewe lambs to reach different rates of body weight gain: CORN, total diet containing 46% of corn (% DM); PCP, total diet containing 46% of pelleted citrus pulp (% DM); and HAY, total diet containing 80% of coastcross hay (% DM). The CORN- and PCP-based diets were formulated for an average daily gain (ADG) of 0.200 kg/day and a HAY-based diet for an ADG of 0.100 kg/day. There was an interaction between treatments and experimental periods for dry matter intake (DMI) (P < 0.01), in which lambs in the CORN treatment presented DMI similar to PCP in the first and second periods, but lambs from the PCP treatment presented lower DMI than the CORN treatment in subsequent periods. In all periods, the body weight, average daily gain, and feed efficiency of CORN lambs were similar to PCP lambs, but higher than HAY lambs. The age at puberty was not affected by treatments; however, lambs fed with non-fibrous carbohydrate sources reached puberty heavier (P < 0.0001) than lambs from the HAY treatment. Despite the high increase in body weight for lambs fed with non-fibrous carbohydrate sources, it did not affect the age of puberty.


Asunto(s)
Carbohidratos de la Dieta/metabolismo , Maduración Sexual/efectos de los fármacos , Ovinos/fisiología , Aumento de Peso , Animales , Peso Corporal , Brasil , Citrus/química , Femenino , Poaceae/química , Distribución Aleatoria , Clima Tropical , Zea mays/química
14.
Trop Anim Health Prod ; 51(6): 1545-1549, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30778808

RESUMEN

This study aimed to evaluate the effect of progesterone (P4) device reutilization in long and short protocols for transcervical timed artificial insemination (TAI) in Santa Inês ewes. A total of 275 multiparous lactating ewes were blocked according to body weight (BW, 49.1 ± 7.3 means ± SE), body condition score (BCS, 2.9 ± 0.4; scale of 1-5), and days postpartum (50 ± 8.2 days), and allocated to one of the treatments. The treatments were arranged in a factorial design, in which the factor 1 was the P4 device type (new or a device of 0.3 g of P4 previously used by 11 days), and the factor 2 was the short or long TAI protocol (P4 device remained by 7 or 11 days, respectively). At device removal, all ewes received 300 IU eCG and 6.70 mg of Dinoprost tromethamine. After TAI protocol, ewes remained with ram by 21 days. There was no interaction between factors in any variables. Ewes that received a new P4 device delayed (P = 0.05) to show estrus compared with ewes receiving a previously used P4 device, but it did not affect pregnancy rate. The long protocol tended to increase pregnancy rate compared with short protocol (33% vs. 24%, respectively; P = 0.07). However, the pregnancy rate at the end of reproductive period was similar in both groups (about 84%). Thus, the use of long protocols tended to improve reproductive performance, and the reused P4 device did not affect pregnancy rate.


Asunto(s)
Progesterona/farmacología , Ovinos/fisiología , Administración Intravaginal , Animales , Dinoprost/administración & dosificación , Dinoprost/análogos & derivados , Dinoprost/farmacología , Estro , Sincronización del Estro/efectos de los fármacos , Femenino , Inseminación Artificial/veterinaria , Lactancia , Embarazo , Índice de Embarazo , Progesterona/administración & dosificación , Reproducción
15.
Hippocampus ; 27(6): 653-667, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28394034

RESUMEN

Alzheimer's disease is characterized by hippocampal atrophy. Other factors also influence the hippocampal volume, but their interactive effect has not been investigated before in cognitively healthy individuals. The aim of this study is to evaluate the interactive effect of key demographic and clinical factors on hippocampal volume, in contrast to previous studies frequently investigating these factors in a separate manner. Also, to investigate how comparable the control groups from ADNI, AIBL, and AddNeuroMed are with five population-based cohorts. In this study, 1958 participants were included (100 AddNeuroMed, 226 ADNI, 155 AIBL, 59 BRC, 295 GENIC, 279 BioFiNDER, 398 PIVUS, and 446 SNAC-K). ANOVA and random forest were used for testing between-cohort differences in demographic-clinical variables. Multiple regression was used to study the influence of demographic-clinical variables on hippocampal volume. ANCOVA was used to analyze whether between-cohort differences in demographic-clinical variables explained between-cohort differences in hippocampal volume. Age and global brain atrophy were the most important variables in explaining variability in hippocampal volume. These variables were not only important themselves but also in interaction with gender, education, MMSE, and total intracranial volume. AddNeuroMed, ADNI, and AIBL differed from the population-based cohorts in several demographic-clinical variables that had a significant effect on hippocampal volume. Variability in hippocampal volume in individuals with normal cognition is high. Differences that previously tended to be related to disease mechanisms could also be partly explained by demographic and clinical factors independent from the disease. Furthermore, cognitively normal individuals especially from ADNI and AIBL are not representative of the general population. These findings may have important implications for future research and clinical trials, translating imaging biomarkers to the general population, and validating current diagnostic criteria for Alzheimer's disease and predementia stages.


Asunto(s)
Hipocampo/anatomía & histología , Estudios de Cohortes , Humanos , Tamaño de los Órganos
16.
J Int Neuropsychol Soc ; 23(6): 511-520, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28494819

RESUMEN

OBJECTIVES: Mild cognitive impairment is common in non-demented Parkinson disease patients (PD-MCI) and is considered as a risk factor for dementia. Executive dysfunction has been widely described in PD and the Verbal Fluency Tests (VFT) are often used for executive function assessment in this pathology. The Movement Disorder Society (MDS) published guidelines for PD-MCI diagnosis in 2012. However, no investigation has focused on the qualitative analysis of VFT in PD-MCI. The aim of this work was to study the clustering and switching strategies in VFT in PD-MCI patients. Moreover, these variables are considered as predictors for PD-MCI diagnosis. METHODS: Forty-three PD patients and twenty normal controls were evaluated with a neuropsychological protocol and the MDS criteria for PD-MCI were applied. Clustering and switching analysis were conducted for VFT. RESULTS: The percentage of patients diagnosed with PD-MCI was 37.2%. The Mann-Whitney U test analysis showed that PD-MCI performed poorly in different cognitive measures (digit span, Wisconsin Card Sorting Test, judgment of line orientation, and comprehension test), compared to PD patients without mild cognitive impairment (PD-nMCI). Phonemic fluency analyses showed that PD-MCI patients produced fewer words and switched significantly less, compared to controls and PD-nMCI. Concerning semantic fluency, the PD-MCI group differed significantly, compared to controls and PD-nMCI, in switches. Discriminant function analyses and logistic regression analyses revealed that switches predicted PD-MCI. CONCLUSIONS: PD-MCI patients showed poor performance in VFT related to the deficient use of production strategies. The number of switches is a useful predictor for incident PD-MCI. (JINS, 2017, 23, 511-520).


Asunto(s)
Disfunción Cognitiva/fisiopatología , Función Ejecutiva/fisiología , Pruebas Neuropsicológicas , Enfermedad de Parkinson/fisiopatología , Anciano , Disfunción Cognitiva/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/complicaciones
17.
Chem Biodivers ; 14(1)2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27623247

RESUMEN

Pinewood nematode (PWN), Bursaphelenchus xylophilus, is the causal agent of pine wilt disease, a serious threat to global forest populations of conifers, especially Pinus spp. A time-course study of the essential oils (EOs) of 2-year-old Pinus halepensis, Pinus pinaster, Pinus pinea and Pinus sylvestris following inoculation with the PWN was performed. The constitutive and nematode inoculation induced EOs components were analyzed at both the wounding or inoculation areas and at the whole plant level. The enantiomeric ratio of optically active main EOs components was also evaluated. External symptoms of infection were observed only in P. pinaster and P. sylvestris 21 and 15 days after inoculation, respectively. The EO composition analysis of uninoculated and unwounded plants revealed the occurrence of chemotypes for P. pinaster, P. halepensis and P. sylvestris, whereas P. pinea showed a homogenous EO composition. When whole plants were evaluated for EO and monoterpene hydrocarbon enantiomeric chemical composition, no relevant qualitative and quantitative differences were found. Instead, EO analysis of inoculated and uninoculated wounded areas revealed an increase of sesquiterpenes and diterpenic compounds, especially in P. pinea and P. halepensis, comparatively to healthy whole plants EOs.


Asunto(s)
Aceites Volátiles/análisis , Pinus/química , Animales , Monoterpenos/análisis , Nematodos/patogenicidad , Infecciones por Nematodos/metabolismo , Aceites Volátiles/química , Enfermedades de las Plantas/parasitología , Terpenos/análisis
18.
Trop Anim Health Prod ; 49(6): 1303-1308, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28608308

RESUMEN

This study aimed to determine whether reproductive performance of ewes submitted to laparoscopic timed artificial insemination (TAI) would be similar to ante meridiem (AM)/post meridiem (PM) rule and assisted natural mating (NM), and whether GnRH may enhance the pregnancy rate in TAI. In experiment I, 191 non-lactating ewes were synchronized, then TAI was performed either 48 h after progesterone (P4) removal (TAI-48 h) or 12 h after estrus detection (AM/PM); moreover, some ewes were submitted to NM (NM) as control treatment. In experiment II, 247 non-lactating ewes were allocated in five treatments, a control (no-GnRH on protocol) and four treatments arranged in a factorial design 2 × 2. The factors were time and dose of GnRH: ewes that received either 10 µg (TAI-10 µg-36 h) or 25 µg of GnRH (TAI-25 µg-36 h) 36 h after P4 removal and ewes that received either 10 µg (TAI-10 µg-48 h) or 25 µg of GnRH (TAI-25 µg-48 h) at time of insemination, 48 h after P4 removal. In experiment I, pregnancy rate in TAI-48 h was lower (P = 0.03) than AM/PM and NM. Moreover, the probability of pregnancy in TAI-48 h was higher (P = 0.06) in ewes detected in estrus early. In experiment II, the use of GnRH in TAI protocols increased (P < 0.01) pregnancy rate at synchronization, and TAI-25 µ-48 h and TAI-10 µg-36 h treatments increased (P = 0.02) pregnancy rate compered to TAI-10 µg-48 h. We conclude that TAI decreased pregnancy rate compered to NM and AM/PM, which may be improved by GnRH use in TAI to synchronize ovulation.


Asunto(s)
Sincronización del Estro , Hormona Liberadora de Gonadotropina/farmacología , Inseminación Artificial/veterinaria , Reproducción , Oveja Doméstica/fisiología , Animales , Brasil , Femenino , Inseminación Artificial/métodos , Embarazo , Índice de Embarazo , Distribución Aleatoria
19.
Chem Biodivers ; 11(5): 719-32, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24827682

RESUMEN

Volatile-oils chemical composition and bioactivity of the essentail oils from Plectranthus barbatus, P. neochilus, and P. ornatus (Lamiaceae) were assessed. Aerial parts from these three related Plectranthus species were collected from cultivated plants grown in Portugal, during vegetative and flowering phases. Volatiles, isolated by distillation-extraction, were analyzed by GC and GC/MS. Monoterpene hydrocarbons (12-74%) and sesquiterpene hydrocarbons (4-45%) constituted the main fractions in all volatiles. α-Pinene (3; 12-67%), oct-1-en-3-ol (6; traces-28%), ß-pinene (7; 0.1-22%), and ß-caryophyllene (50; 7-12%) dominated P. barbatus volatiles. P. neochilus major volatile components were α-terpenyl acetate (41; traces-48%), α-thujone (2; 2-28%), ß-caryophyllene (50; 2-28%), ß-pinene (7; 1-25%), and α-pinene (3; 1-19%). Oct-1-en-3-ol (6; 13-31%), ß-pinene (7; 11-24%), α-pinene (3; 11-19%), and ß-caryophyllene (50; traces-11%) were the main constituents from P. ornatus volatiles. These chemical compositions were rather different from those previously found for specimens harvested in Africa and Brazil. Moreover, the volatiles from the flowers are herewith reported for the first time. Essential oils, isolated by hydrodistillation from leaves and stems, showed a yellowish color and unpleasant odor, with yields ranging from 0.08% to 0.84% (v/dry weight). Antioxidant and antimicrobial activities of the essential oils were evaluated by DPPH· and TBARS assays, and agar disc-diffusion method, respectively. Results showed low or moderate antioxidant capacity and significant antimicrobial activity against Gram-positive bacteria.


Asunto(s)
Antiinfecciosos/química , Antioxidantes/química , Aceites Volátiles/química , Aceites de Plantas/química , Plectranthus/química , Antiinfecciosos/aislamiento & purificación , Antiinfecciosos/farmacología , Antioxidantes/aislamiento & purificación , Antioxidantes/farmacología , Bacterias/efectos de los fármacos , Infecciones Bacterianas/tratamiento farmacológico , Hongos/efectos de los fármacos , Humanos , Micosis/tratamiento farmacológico , Aceites Volátiles/aislamiento & purificación , Aceites Volátiles/farmacología , Aceites de Plantas/aislamiento & purificación , Aceites de Plantas/farmacología
20.
Front Psychol ; 15: 1407583, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39355297

RESUMEN

Objectives: We aimed to advance our understanding of the effect of chess on cognition by expanding previous univariate studies with the use of graph theory on cognitive data. Specifically, we investigated the cognitive connectome of adult chess players. Method: We included 19 chess players and 19 controls with ages between 39 and 69 years. Univariate analysis and graph theory included 27 cognitive measures representing multiple cognitive domains and subdomains. Graph analysis included global and nodal measures of integration, segregation, and centrality. We also performed an analysis of community structures to gain an additional understanding of the cognitive architecture of chess players. Results: The analysis of global graph measures showed that chess players had a higher local efficiency than controls at the cost of a lower global efficiency, which did not permeate segregation aspects of their connectome. The nodal graph measures showed that executive/attention/processing speed and visuoconstructive nodes had a central role in the connectome of chess players. The analysis of communities showed that chess players had a slightly reorganized cognitive architecture into three modules. These graph theory findings were in the context of better cognitive performance in chess players than controls in visuospatial abilities. Conclusion: We conclude that the cognitive architecture of chess players is slightly reorganized into functionally and anatomically coherent modules reflecting a distinction between visual, verbal, and executive/attention/processing speed-related functions, perhaps reminiscent of right hemisphere and left hemisphere subnetworks orchestrated by the frontal lobe and its white matter connections.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA