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1.
Int J Mol Sci ; 24(9)2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37175497

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide, and its incidence has been increasing in recent years because of the high prevalence of obesity and metabolic syndrome in the Western population. Alcohol-related liver disease (ArLD) is the most common cause of cirrhosis and constitutes the leading cause of cirrhosis-related deaths worldwide. Both NAFLD and ArLD constitute well-known causes of liver damage, with some similarities in their pathophysiology. For this reason, they can lead to the progression of liver disease, being responsible for a high proportion of liver-related events and liver-related deaths. Whether ArLD impacts the prognosis and progression of liver damage in patients with NAFLD is still a matter of debate. Nowadays, the synergistic deleterious effect of obesity and diabetes is clearly established in patients with ArLD and heavy alcohol consumption. However, it is still unknown whether low to moderate amounts of alcohol are good or bad for liver health. The measurement and identification of the possible synergistic deleterious effect of alcohol consumption in the assessment of patients with NAFLD is crucial for clinicians, since early intervention, advising abstinence and controlling cardiovascular risk factors would improve the prognosis of patients with both comorbidities. This article seeks to perform a comprehensive review of the pathophysiology of both disorders and measure the impact of alcohol consumption in patients with NAFLD.


Assuntos
Síndrome Metabólica , Hepatopatia Gordurosa não Alcoólica , Humanos , Cirrose Hepática/epidemiologia , Obesidade/complicações , Obesidade/epidemiologia
2.
United European Gastroenterol J ; 11(10): 1010-1020, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38015591

RESUMO

BACKGROUND: Preliminary evidence suggests that inherited hypercoagulable disorders can lead to an increased risk of significant liver fibrosis. OBJECTIVE: We aimed to investigate the prevalence of significant fibrosis in patients with inherited thrombophilia, assessed by using liver stiffness (LS), and to compare this prevalence to that found in a large population-based cohort from the same region. METHODS: This was a single-center, cross-sectional study. A complete laboratory analysis for liver disease, LS by transient elastography and an abdominal ultrasound were performed in patients with inherited thrombophilia diagnosed between May 2013-February 2017. These patients were propensity score matched (ratio 1:4) with a population-based cohort from the same region (PREVHEP-ETHON study; NCT02749864; N = 5988). RESULTS: Of 241 patients with inherited thrombophilia, eight patients (3.3%) had significant fibrosis (LS ≥8 kPa). All of them had risk factors for liver disease and met diagnostic criteria for different liver diseases. After matching 221 patients with thrombophilia with 884 patients of the PREVHEP-ETHON cohort, the prevalence of significant fibrosis was similar between both cohorts (1.8% vs. 3.6%, p = 0.488). Multivariate analysis showed that age and liver disease risk factors, but not belonging to the thrombophilia cohort, were associated with the presence of significant fibrosis. The magnitude of the increased risk of significant fibrosis in patients with risk factors for liver disease was also similar in both cohorts. CONCLUSIONS: Our findings do not provide evidence supporting an association between inherited thrombophilia and an increased risk of significant liver fibrosis, independent of the presence of liver-related causes of fibrosis.


Assuntos
Hepatopatias , Trombofilia , Humanos , Estudos Transversais , Cirrose Hepática/diagnóstico , Hepatopatias/complicações , Trombofilia/complicações , Trombofilia/epidemiologia , Trombofilia/genética
3.
J Vis ; 12(6): 13, 2012 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-22693331

RESUMO

A visual target is more difficult to recognize when it is surrounded by other, similar objects. This breakdown in object recognition is known as crowding. Despite a long history of experimental work, computational models of crowding are still sparse. Specifically, few studies have examined crowding using an ideal-observer approach. Here, we compare crowding in ideal observers with crowding in humans. We derived an ideal-observer model for target identification under conditions of position and identity uncertainty. Simulations showed that this model reproduces the hallmark of crowding, namely a critical spacing that scales with viewing eccentricity. To examine how well the model fits quantitatively to human data, we performed three experiments. In Experiments 1 and 2, we measured observers' perceptual uncertainty about stimulus positions and identities, respectively, for a target in isolation. In Experiment 3, observers identified a target that was flanked by two distractors. We found that about half of the errors in Experiment 3 could be accounted for by the perceptual uncertainty measured in Experiments 1 and 2. The remainder of the errors could be accounted for by assuming that uncertainty (i.e., the width of internal noise distribution) about stimulus positions and identities depends on flanker proximity. Our results provide a mathematical restatement of the crowding problem and support the hypothesis that crowding behavior is a sign of optimality rather than a perceptual defect.


Assuntos
Simulação por Computador , Aglomeração , Percepção de Forma/fisiologia , Modelos Neurológicos , Percepção Espacial/fisiologia , Adulto , Feminino , Humanos , Masculino , Estimulação Luminosa/métodos , Incerteza , Adulto Jovem
4.
J Clin Med ; 11(21)2022 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-36362663

RESUMO

Portal vein thrombosis constitutes the most common thrombotic event in patients with cirrhosis, with increased rates in the setting of advanced liver disease. Despite being a well-known complication of cirrhosis, the contribution of portal vein thrombosis to hepatic decompensation and overall mortality is still a matter of debate. The incorporation of direct oral anticoagulants and new radiological techniques for portal vein recanalization have expanded our therapeutic arsenal. However, the lack of large prospective observational studies and randomized trials explain the heterogenous diagnostic and therapeutic recommendations of current guidelines. This article seeks to make a comprehensive review of the pathophysiology, clinical features, diagnosis, and treatment of portal vein thrombosis in patients with cirrhosis.

5.
Data Brief ; 41: 107896, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35198677

RESUMO

Several research studies have investigated the human activity recognition (HAR) domain to detect and recognise patterns of daily human activities. However, the accurate and automatic assessment of activities of daily living (ADLs) through machine learning algorithms is still a challenge, especially due to limited availability of realistic datasets to train and test such algorithms. The dataset contains data from 52 participants in total (26 women, and 26 men). The data for these participants was collected in two phases: 33 participants initially, and 19 further participants later on. Participants performed up to 5 repetitions of 24 different ADLs. Firstly, we provide an annotated description of the dataset collected by wearing a wrist-worn measurement device, Empatica E4. Secondly, we describe the methodology of the data collection and the real context in which participants performed the selected activities. Finally, we present some examples of recent and relevant target applications where our dataset can be used, namely lifelogging, behavioural analysis and measurement device evaluation. The authors consider the dissemination of this dataset can highly benefit the research community, and specially those involved in the recognition of ADLs, and/or in the removal of cues that reveal identity.

6.
Cell Motil Cytoskeleton ; 63(11): 710-24, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16960886

RESUMO

Tau, a microtubule-associated protein enriched in the axon, is known to stabilize and promote the formation of microtubules during axonal outgrowth. Several studies have reported that tau was associated with membranes. In the present study, we further characterized the interaction of tau with membranous elements by examining its distribution in subfractions enriched in either Golgi or endoplasmic reticulum membranes isolated from rat brain. A subfraction enriched with markers of the medial Golgi compartment, MG160 and mannosidase II, presented a high tau content indicating that tau was associated with these membranes. Electron microscope morphometry confirmed the enrichment of this subfraction with Golgi membranes. Double-immunogold labeling experiments conducted on this subfraction showed the direct association of tau with vesicles labeled with either an antibody directed against MG160 or TGN38. The association of tau with the Golgi membranes was further confirmed by immunoisolating Golgi membranes with an anti-tau antibody. Immunogold labeling confirmed the presence of tau on the Golgi membranes in neurons in vivo. Overexpression of human tau in primary hippocampal neurons induced the formation of large Golgi vesicles that were found in close vicinity to tau-containing microtubules. This suggested that tau could serve as a link between Golgi membranes and microtubules. Such role for tau was demonstrated in an in vitro reconstitution assay. Finally, our results showed that some tau isoforms present in the Golgi subfraction were phosphorylated at the sites recognized by the phosphorylation-dependent antibodies PHF-1 and AT-8.


Assuntos
Complexo de Golgi/metabolismo , Membranas Intracelulares/metabolismo , Microtúbulos/metabolismo , Proteínas tau/metabolismo , Animais , Encéfalo/ultraestrutura , Células Cultivadas , Complexo de Golgi/ultraestrutura , Hipocampo/ultraestrutura , Imuno-Histoquímica , Membranas Intracelulares/ultraestrutura , Camundongos , Microscopia Eletrônica , Microtúbulos/química , Microtúbulos/ultraestrutura , Neurônios/química , Neurônios/fisiologia , Neurônios/ultraestrutura , Fosforilação , Ratos , Ratos Sprague-Dawley , Frações Subcelulares/química , Frações Subcelulares/metabolismo , Frações Subcelulares/ultraestrutura , Proteínas tau/química
7.
J Biol Chem ; 280(10): 9439-49, 2005 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-15623521

RESUMO

Neurons are polarized cells presenting two distinct compartments, dendrites and an axon. Dendrites can be distinguished from the axon by the presence of rough endoplasmic reticulum (RER). The mechanism by which the structure and distribution of the RER is maintained in these cells is poorly understood. In the present study, we investigated the role of the dendritic microtubule-associated protein-2 (MAP2) in the RER membrane positioning by comparing their distribution in brain subcellular fractions and in primary hippocampal cells and by examining the MAP2-microtubule interaction with RER membranes in vitro. Subcellular fractionation of rat brain revealed a high MAP2 content in a subfraction enriched with the endoplasmic reticulum markers ribophorin and p63. Electron microscope morphometry confirmed the enrichment of this subfraction with RER membranes. In cultured hippocampal neurons, MAP2 and p63 were found to concomitantly compartmentalize to the dendritic processes during neuronal differentiation. Protein blot overlays using purified MAP2c protein revealed its interaction with p63, and immunoprecipitation experiments performed in HeLa cells showed that this interaction involves the projection domain of MAP2. In an in vitro reconstitution assay, MAP2-containing microtubules were observed to bind to RER membranes in contrast to microtubules containing tau, the axonal MAP. This binding of MAP2c microtubules was reduced when an anti-p63 antibody was added to the assay. The present results suggest that MAP2 is involved in the association of RER membranes with microtubules and thereby could participate in the differential distribution of RER membranes within a neuron.


Assuntos
Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/metabolismo , Fatores de Transcrição/metabolismo , Animais , Encéfalo/embriologia , Encéfalo/metabolismo , Bovinos , Linhagem Celular , Embrião de Mamíferos , Embrião não Mamífero , Retículo Endoplasmático/fisiologia , Retículo Endoplasmático/ultraestrutura , Complexo de Golgi/metabolismo , Complexo de Golgi/ultraestrutura , Hipocampo/fisiologia , Membranas Intracelulares/metabolismo , Microscopia Eletrônica , Microssomos/metabolismo , Microssomos/ultraestrutura , Microtúbulos/ultraestrutura , Neurônios/fisiologia , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/metabolismo , Spodoptera , Transfecção
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