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1.
Food Res Int ; 186: 114306, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729707

RESUMO

The aim of this research was to find out the effect of different combinations of starter and non-starter cultures on the proteolysis of Castellano cheese during ripening. Four cheese batches were prepared, each containing autochthonous lactobacilli and or Leuconostoc, and were compared with each other and with a control batch, that used only a commercial starter. To achieve this, nitrogen fractions (pH 4.4-soluble nitrogen and 12 % trichloroacetic acid soluble nitrogen, polypeptide nitrogen and casein nitrogen), levels of free amino acids and biogenic amines were assessed. Texture and microstructure of cheeses were also evaluated. Significant differences in nitrogen fractions were observed between batches at different stages of ripening. The free amino acid content increased throughout the cheese ripening process, with a more significant increase occurring after the first 30 days. Cheeses containing non-starter lactic acid bacteria exhibited the highest values at the end of the ripening period. Among the main amino acids, GABA was particularly abundant, especially in three of the cheese batches at the end of ripening. The autochthonous lactic acid bacteria were previously selected as non-producers of biogenic amines and this resulted in the absence of these compounds in the cheeses. Analysis of the microstructure of the cheese reflected the impact of proteolysis. Additionally, the texture profile analysis demonstrated that the cheese's hardness intensified as the ripening period progressed. The inclusion of autochthonous non-starter lactic acid bacteria in Castellano cheese production accelerated the proteolysis process, increasing significantly the free amino acids levels and improving the sensory quality of the cheeses.


Assuntos
Aminoácidos , Aminas Biogênicas , Queijo , Proteólise , Queijo/microbiologia , Queijo/análise , Aminoácidos/análise , Aminoácidos/metabolismo , Aminas Biogênicas/análise , Microbiologia de Alimentos , Manipulação de Alimentos/métodos , Leuconostoc/metabolismo , Leuconostoc/crescimento & desenvolvimento , Lactobacillus/metabolismo , Lactobacillus/crescimento & desenvolvimento , Nitrogênio/análise , Qualidade dos Alimentos , Fermentação
2.
Sci Transl Med ; 16(737): eadf4601, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38446899

RESUMO

Patients with cancer undergoing chemotherapy frequently experience a neurological condition known as chemotherapy-related cognitive impairment, or "chemobrain," which can persist for the remainder of their lives. Despite the growing prevalence of chemobrain, both its underlying mechanisms and treatment strategies remain poorly understood. Recent findings suggest that chemobrain shares several characteristics with neurodegenerative diseases, including chronic neuroinflammation, DNA damage, and synaptic loss. We investigated whether a noninvasive sensory stimulation treatment we term gamma entrainment using sensory stimuli (GENUS), which has been shown to alleviate aberrant immune and synaptic pathologies in mouse models of neurodegeneration, could also mitigate chemobrain phenotypes in mice administered a chemotherapeutic drug. When administered concurrently with the chemotherapeutic agent cisplatin, GENUS alleviated cisplatin-induced brain pathology, promoted oligodendrocyte survival, and improved cognitive function in a mouse model of chemobrain. These effects persisted for up to 105 days after GENUS treatment, suggesting the potential for long-lasting benefits. However, when administered to mice 90 days after chemotherapy, GENUS treatment only provided limited benefits, indicating that it was most effective when used to prevent the progression of chemobrain pathology. Furthermore, we demonstrated that the effects of GENUS in mice were not limited to cisplatin-induced chemobrain but also extended to methotrexate-induced chemobrain. Collectively, these findings suggest that GENUS may represent a versatile approach for treating chemobrain induced by different chemotherapy agents.


Assuntos
Comprometimento Cognitivo Relacionado à Quimioterapia , Disfunção Cognitiva , Humanos , Animais , Camundongos , Cisplatino/efeitos adversos , Cognição , Dano ao DNA , Modelos Animais de Doenças
3.
Nature ; 627(8002): 149-156, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38418876

RESUMO

The glymphatic movement of fluid through the brain removes metabolic waste1-4. Noninvasive 40 Hz stimulation promotes 40 Hz neural activity in multiple brain regions and attenuates pathology in mouse models of Alzheimer's disease5-8. Here we show that multisensory gamma stimulation promotes the influx of cerebrospinal fluid and the efflux of interstitial fluid in the cortex of the 5XFAD mouse model of Alzheimer's disease. Influx of cerebrospinal fluid was associated with increased aquaporin-4 polarization along astrocytic endfeet and dilated meningeal lymphatic vessels. Inhibiting glymphatic clearance abolished the removal of amyloid by multisensory 40 Hz stimulation. Using chemogenetic manipulation and a genetically encoded sensor for neuropeptide signalling, we found that vasoactive intestinal peptide interneurons facilitate glymphatic clearance by regulating arterial pulsatility. Our findings establish novel mechanisms that recruit the glymphatic system to remove brain amyloid.


Assuntos
Doença de Alzheimer , Amiloide , Encéfalo , Líquido Cefalorraquidiano , Líquido Extracelular , Ritmo Gama , Sistema Glinfático , Animais , Camundongos , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Doença de Alzheimer/prevenção & controle , Amiloide/metabolismo , Aquaporina 4/metabolismo , Astrócitos/metabolismo , Encéfalo/citologia , Encéfalo/metabolismo , Encéfalo/patologia , Líquido Cefalorraquidiano/metabolismo , Modelos Animais de Doenças , Líquido Extracelular/metabolismo , Sistema Glinfático/fisiologia , Interneurônios/metabolismo , Peptídeo Intestinal Vasoativo/metabolismo , Córtex Cerebral/citologia , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Estimulação Elétrica
4.
BMJ Case Rep ; 14(5)2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34011646

RESUMO

Primary intramedullary spinal-cord lymphoma (PISCL) is a rare cause of myelopathy and constitutes only 1% of central nervous system lymphomas. Delay to diagnosis is common due to its rarity, its similarity to other causes of myelopathy and the difficulties in obtaining pathological diagnosis. We report a case of PISCL and discuss the challenges faced on diagnosis, namely the impact of corticosteroids on histological findings, the usefulness of MRI, positron-emission tomography/CT (PET/CT) and repeated lumbar punctures.


Assuntos
Linfoma não Hodgkin , Doenças da Medula Espinal , Neoplasias da Medula Espinal , Humanos , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Medula Espinal/diagnóstico por imagem , Neoplasias da Medula Espinal/cirurgia , Tomografia Computadorizada por Raios X
5.
BMC Biol ; 19(1): 65, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33823872

RESUMO

BACKGROUND: Homeostatic regulation of sleep is reflected in the maintenance of a daily balance between sleep and wakefulness. Although numerous internal and external factors can influence sleep, it is unclear whether and to what extent the process that keeps track of time spent awake is determined by the content of the waking experience. We hypothesised that alterations in environmental conditions may elicit different types of wakefulness, which will in turn influence both the capacity to sustain continuous wakefulness as well as the rates of accumulating sleep pressure. To address this, we compared the effects of repetitive behaviours such as voluntary wheel running or performing a simple touchscreen task, with wakefulness dominated by novel object exploration, on sleep timing and EEG slow-wave activity (SWA) during subsequent NREM sleep. RESULTS: We find that voluntary wheel running is associated with higher wake EEG theta-frequency activity and results in longer wake episodes, as compared with exploratory behaviour; yet, it does not lead to higher levels of EEG SWA during subsequent NREM sleep in either the frontal or occipital derivation. Furthermore, engagement in a touchscreen task, motivated by food reward, results in lower SWA during subsequent NREM sleep in both derivations, as compared to exploratory wakefulness, even though the total duration of wakefulness is similar. CONCLUSION: Overall, our study suggests that sleep-wake behaviour is highly flexible within an individual and that the homeostatic processes that keep track of time spent awake are sensitive to the nature of the waking experience. We therefore conclude that sleep dynamics are determined, to a large degree, by the interaction between the organism and the environment.


Assuntos
Comportamento Exploratório , Camundongos/fisiologia , Atividade Motora , Corrida , Sono/fisiologia , Vigília , Animais , Masculino , Camundongos Endogâmicos C57BL , Sono de Ondas Lentas/fisiologia
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