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1.
eNeuro ; 10(4)2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37068950

RESUMO

In addition to brain disorders, which constitute a devastating consequence of prenatal alcohol exposure (PAE), eye development is also significantly affected. Given that the retina is a readily accessible part of the central nervous system, a better understanding of the impact of ethanol on retinal development might provide ophthalmological landmarks helpful for early diagnosis of fetal alcohol syndrome. This study aimed to provide a fine morphometric and cellular characterization of the development of retinal microvasculature and neurovascular interactions in a mouse model of fetal alcohol spectrum disorder (FASD). The data revealed that PAE impaired superficial vascular plexus development. In particular, progression of the vascular migration front was significantly decreased in PAE retinas, supporting a delay in plexus progression. Moreover, a significant decrease in the vessel density and number of perforating vessels was quantified in PAE mice, supporting less angiogenesis. The present study provides also the first evidence of a close interaction between migrating calretinin-positive interneurons and perforating microvessels in the inner nuclear layer of the developing retina. This neurovascular association was significantly impaired by PAE. Moreover, projections of amacrine cells were abnormally distributed and densified in stratum S1 and S2. In humans, comparison of a five-month-old control infant with a three-month-old alcohol-exposed case revealed a similar mispositioning of calretinin-positive interneurons. This opens new research avenues regarding a neurovascular contribution in the deleterious effects of alcohol in the developing retina and support that ophthalmological examination could become a promising approach for early detection of alcohol-exposed infants presenting with neurovascular brain defects.


Assuntos
Transtornos do Espectro Alcoólico Fetal , Efeitos Tardios da Exposição Pré-Natal , Animais , Feminino , Humanos , Lactente , Camundongos , Gravidez , Calbindina 2 , Etanol/toxicidade , Transtornos do Espectro Alcoólico Fetal/diagnóstico , Interneurônios , Microvasos , Retina
2.
Curr Biol ; 32(23): 4997-5007.e5, 2022 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-36334586

RESUMO

Only 400 km off the coast of East Africa, the island of Madagascar is one of the last large land masses to have been colonized by humans. While many questions surround the human occupation of Madagascar, recent studies raise the question of human impact on endemic biodiversity and landscape transformation. Previous genetic and linguistic analyses have shown that the Malagasy population has emerged from an admixture that happened during the last millennium, between Bantu-speaking African populations and Austronesian-speaking Asian populations. By studying the sharing of chromosome segments between individuals (IBD determination), local ancestry information, and simulated genetic data, we inferred that the Malagasy ancestral Asian population was isolated for more than 1,000 years with an effective size of just a few hundred individuals. This isolation ended around 1,000 years before present (BP) by admixture with a small African population. Around the admixture time, there was a rapid demographic expansion due to intrinsic population growth of the newly admixed population, which coincides with extensive changes in Madagascar's landscape and the extinction of all endemic large-bodied vertebrates. Therefore, our approach can provide new insights into past human demography and associated impacts on ecosystems.


Assuntos
Ecossistema , Crescimento Demográfico , Humanos , Madagáscar
3.
Eur Child Adolesc Psychiatry ; 30(3): 331-346, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32034554

RESUMO

"Impairments in emotional information processing are frequently reported in attention deficit hyperactivity disorder (ADHD) at a voluntary, explicit level (e.g., emotion recognition) and at an involuntary, implicit level (e.g., emotional interference). Most of previous studies have used faces with emotional expressions, rarely examining other important sources of information usually co-occurring with faces in our every day experience. Here, we examined how the emotional content of an entire visual scene depicting real-world environments and situations is processed in ADHD. We systematically reviewed in PubMed, SCOPUS and ScienceDirect, using the PRISMA guidelines, empirical studies published in English until March 2019, about processing of visual scenes, with or without emotional content, in children and adolescents with ADHD. We included 17 studies among the 154 initially identified. Fifteen used scenes with emotional content (which was task-relevant in seven and irrelevant in eight studies) and two used scenes without emotional content. Even though the interpretation of the results differed according to the theoretical model of emotions of the study and the presence of comorbidity, differences in scene information processing between ADHD and typically developing children and adolescents were reported in all but one study. ADHD children and adolescents show difficulties in the processing of emotional information conveyed by visual scenes, which may stem from a stronger bottom-up impact of emotional stimuli in ADHD, increasing the emotional experience, and from core deficits of the disorder, decreasing the overall processing of the scene".


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Emoções/fisiologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino
4.
Sci Rep ; 10(1): 11961, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32665643

RESUMO

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

5.
Sci Rep ; 10(1): 8447, 2020 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-32439874

RESUMO

Visual categorization improves when object-context associations in scenes are semantically consistent, thus predictable from schemas stored in long-term memory. However, it is unclear whether this is due to differences in early perceptual processing, in matching of memory representations or in later stages of response selection. We tested these three concurrent explanations across five experiments. At each trial, participants had to categorize a scene context and an object briefly presented within the same image (Experiment 1), or separately in simultaneous images (Experiments 2-5). We analyzed unilateral (Experiments 1, 3) and bilateral presentations (Experiments 2, 4, 5), and presentations on the screen's horizontal midline (Experiments 1-2) and in the upper and lower visual fields (Experiments 3, 4). In all the experiments, we found a semantic consistency advantage for both context categorization and object categorization. This shows that the memory for object-context semantic associations is activated regardless of whether these two scene components are integrated in the same percept. Our study suggests that the facilitation effect of semantic consistency on categorization occurs at the stage of matching the percept with previous knowledge, supporting the object selection account and extending this framework to an object-context reciprocal influence on matching processes (object-context selection account).


Assuntos
Atenção/fisiologia , Memória/fisiologia , Reconhecimento Visual de Modelos , Tempo de Reação , Semântica , Percepção Visual/fisiologia , Adulto , Discriminação Psicológica , Feminino , Humanos , Masculino , Estimulação Luminosa
6.
Am J Physiol Endocrinol Metab ; 313(2): E107-E120, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28400412

RESUMO

Obesity and its related disorders have been associated with the presence in the blood of gut bacteria-derived lipopolysaccharides (LPS). However, the factors underlying this low-grade elevation in plasma LPS, so-called metabolic endotoxemia, are not fully elucidated. We aimed to investigate the effects of Western diet (WD) feeding on intestinal and hepatic LPS handling mechanisms in a rat model of diet-induced obesity (DIO). Rats were fed either a standard chow diet (C) or a Western Diet (WD, 45% fat) for 6 wk. They were either fed ad libitum or pair-fed to match the caloric intake of C rats for the first week, then fed ad libitum for the remaining 5 wk. Six-week WD feeding led to a mild obese phenotype with increased adiposity and elevated serum LPS-binding protein (LBP) levels relative to C rats, irrespective of initial energy intake. Serum LPS was not different between dietary groups but exhibited strong variability. Disrupted ileal mucus secretion and decreased ileal Reg3-γ and -ß gene expression along with high ileal permeability to LPS were observed in WD compared with C-fed rats. Ileal and cecal intestinal alkaline phosphatase (IAP) activity as well as Verrucomicrobia and Bifidobacterium cecal levels were increased in WD-fed rats compared with C-fed rats. WD consumption did not impact mRNA levels of LPS-handling hepatic enzymes. Correlation analysis revealed that ileal passage of LPS, IAP activity, Proteobacteria levels and hepatic aoah gene expression correlated with serum LPS and LBP, suggesting that ileal mucosal defense impairment induced by WD feeding contribute to metabolic endotoxemia.


Assuntos
Dieta Ocidental , Ingestão de Alimentos/fisiologia , Endotoxemia/metabolismo , Íleo/metabolismo , Mucosa Intestinal/metabolismo , Animais , Células Cultivadas , Endotoxemia/patologia , Comportamento Alimentar , Íleo/patologia , Mucosa Intestinal/patologia , Masculino , Técnicas de Cultura de Órgãos , Permeabilidade , Ratos , Ratos Wistar
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