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1.
Neuroimage ; 285: 120488, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38065278

RESUMO

A model based on inhibitory coupling has been proposed to explain perceptual oscillations. This 'adapting reciprocal inhibition' model postulates that it is the strength of inhibitory coupling that determines the fate of competition between percepts. Here, we used an fMRI-based adaptation technique to reveal the influence of neighboring neuronal populations, such as reciprocal inhibition, in motion-selective hMT+/V5. If reciprocal inhibition exists in this region, the following predictions should hold: 1. stimulus-driven response would not simply decrease, as predicted by simple repetition-suppression of neuronal populations, but instead, increase due to the activity from adjacent populations; 2. perceptual decision involving competing representations, should reflect decreased reciprocal inhibition by adaptation; 3. neural activity for the competing percept should also later on increase upon adaptation. Our results confirm these three predictions, showing that a model of perceptual decision based on adapting reciprocal inhibition holds true. Finally, they also show that the net effect of the well-known repetition suppression phenomenon can be reversed by this mechanism.


Assuntos
Inibição Psicológica , Neurônios , Humanos
2.
Artigo em Inglês | MEDLINE | ID: mdl-38967213

RESUMO

BACKGROUND AND AIM: Inflammatory bowel disease is challenging to diagnose. Fecal biomarkers offer noninvasive solutions. The renin-angiotensin-aldosterone system is implicated in intestinal inflammation. Angiotensin-converting enzyme (ACE) and angiotensin-converting enzyme 2 (ACE2) regulate its activity, but conflicting findings on these enzymes in colitis require further investigation. We aimed to assess ACE and ACE2 presence and activities in the feces, serum, and colon of 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced rats. METHODS: Colitis was induced in male rats by rectal instillation of a 21% ethanolic TNBS solution. After rats' sacrifice, colonic portions, serum, and feces were collected. ACE and ACE2 presence in the feces was analyzed by western Blot, and colonic and serum enzymes' concentrations were quantified using ELISA kits. ACE activity was assessed using Hippuryl-His-Leu and Z-Phe-His-Leu as substrates. ACE2 activity was assessed using Mca-APK (Dnp) as a substrate in the presence and absence of DX600 (ACE2 inhibitor). RESULTS: An ACE isoform of ~70 kDa was found only in the feces of TNBS-induced rats. ACE concentration was higher than that of ACE2 in the serum and the inflamed colon. ACE N-domain activity was higher than that of the C-domain in all matrices. ACE2 activity was higher in the feces of TNBS-induced animals compared to controls. CONCLUSION: A 70 kDa ACE isoform only detected in the feces of TNBS-induced rats may have translational relevance. ACE N-domain seems to play a significant role in regulating colonic lesions. Further research using human samples is necessary to validate these findings.

3.
Inflamm Res ; 72(3): 475-491, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36617343

RESUMO

BACKGROUND: Cysteinyl leukotrienes (CysLT) are potent inflammation-promoting mediators, but remain scarcely explored in COVID-19. We evaluated urinary CysLT (U-CysLT) relationship with disease severity and their usefulness for prognostication in hospitalized COVID-19 patients. The impact on U-CysLT of veno-venous extracorporeal membrane oxygenation (VV-ECMO) and of comorbidities such as hypertension and obesity was also assessed. METHODS: Blood and spot urine were collected in "severe" (n = 26), "critically ill" (n = 17) and "critically ill on VV-ECMO" (n = 17) patients with COVID-19 at days 1-2 (admission), 3-4, 5-8 and weekly thereafter, and in controls (n = 23) at a single time point. U-CysLT were measured by ELISA. Routine markers, prognostic scores and outcomes were also evaluated. RESULTS: U-CysLT did not differ between groups at admission, but significantly increased along hospitalization only in critical groups, being markedly higher in VV-ECMO patients, especially in hypertensives. U-CysLT values during the first week were positively associated with ICU and total hospital length of stay in critical groups and showed acceptable area under curve (AUC) for prediction of 30-day mortality (AUC: 0.734, p = 0.001) among all patients. CONCLUSIONS: U-CysLT increase during hospitalization in critical COVID-19 patients, especially in hypertensives on VV-ECMO. U-CysLT association with severe outcomes suggests their usefulness for prognostication and as therapeutic targets.


Assuntos
COVID-19 , Humanos , COVID-19/terapia , Leucotrienos , Biomarcadores , Cisteína , Estudos Retrospectivos
4.
Cogn Affect Behav Neurosci ; 22(6): 1275-1289, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35857280

RESUMO

Facial emotion perception can be studied from the point of view of dynamic systems whose output may depend not only on current input but also on prior history - a phenomenon known as hysteresis. In cognitive neuroscience, hysteresis has been described as positive (perceptual persistence) or negative (fatigue of current percept) depending on whether perceptual switching occurs later or earlier than actual physical stimulus changes. However, its neural correlates remain elusive. We used dynamic transitions between emotional expressions and combined behavioral assessment with functional magnetic resonance imaging (fMRI) to investigate the underlying circuitry of perceptual hysteresis in facial emotion recognition. Our findings revealed the involvement of face-selective visual areas - fusiform face area (FFA) and superior temporal sulcus (STS) - in perceptual persistence as well as the right anterior insula. Moreover, functional connectivity analyses revealed an interplay between the right anterior insula and medial prefrontal cortex, which showed to be dependent on the presence of positive hysteresis. Our results support the hypothesis that high-order regions are involved in perceptual stabilization and decision during perceptual persistence (positive hysteresis) and add evidence to the role of the anterior insula as a hub of sensory information in perceptual decision-making.


Assuntos
Reconhecimento Facial , Humanos , Expressão Facial , Lobo Temporal , Emoções , Imageamento por Ressonância Magnética/métodos , Córtex Pré-Frontal/diagnóstico por imagem , Mapeamento Encefálico
5.
Hum Brain Mapp ; 42(6): 1920-1929, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33576552

RESUMO

Neuroimaging studies have suggested that hMT+ encodes global motion interpretation, but this contradicts the notion that BOLD activity mainly reflects neuronal input. While measuring fMRI responses at 7 Tesla, we used an ambiguous moving stimulus, yielding the perception of two incoherently moving surfaces-component motion-or only one coherently moving surface-pattern motion, to induce perceptual fluctuations and identify perceptual organization size-matched domains in hMT+. Then, moving gratings, exactly matching either the direction of component or pattern motion percepts of the ambiguous stimulus, were shown to the participants to investigate whether response properties reflect the input or decision. If hMT+ responses reflect the input, component motion domains (selective to incoherent percept) should show grating direction stimulus-dependent changes, unlike pattern motion domains (selective to the coherent percept). This hypothesis is based on the known direction-selective nature of inputs in component motion perceptual domains versus non-selectivity in pattern motion perceptual domains. The response amplitude of pattern motion domains did not change with grating direction (consistently with their non-selective input), in contrast to what happened for the component motion domains (consistently with their selective input). However, when we analyzed relative ratio measures they mirrored perceptual interpretation. These findings are consistent with the notion that patterns of BOLD responses reflect both sensory input and perceptual read-out.


Assuntos
Mapeamento Encefálico , Percepção de Movimento/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Córtex Visual Primário/fisiologia , Adulto , Tomada de Decisões/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Córtex Visual Primário/diagnóstico por imagem , Adulto Jovem
6.
Int J Mol Sci ; 22(9)2021 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-34063607

RESUMO

Angiotensin II (Ang II) regulates colon contraction, acting not only directly on smooth muscle but also indirectly, interfering with myenteric neuromodulation mediated by the activation of AT1 /AT2 receptors. In this article, we aimed to explore which mediators and cells were involved in Ang II-mediated colonic contraction in the TNBS-induced rat model of colitis. The contractile responses to Ang II were evaluated in distinct regions of the colon of control animals or animals with colitis in the absence and presence of different antagonists/inhibitors. Endogenous levels of Ang II in the colon were assessed by ELISA and the number of AT1/AT2 receptors by qPCR. Ang II caused AT1 receptor-mediated colonic contraction that was markedly decreased along the colons of TNBS-induced rats, consistent with reduced AT1 mRNA expression. However, the effect mediated by Ang II is much more intricate, involving (in addition to smooth muscle cells and nerve terminals) ICC and EGC, which communicate by releasing ACh and NO in a complex mechanism that changes colitis, unveiling new therapeutic targets.


Assuntos
Angiotensina II/genética , Colite/genética , Doenças Inflamatórias Intestinais/genética , Sistema Renina-Angiotensina/genética , Antagonistas de Receptores de Angiotensina/farmacologia , Animais , Colite/fisiopatologia , Colo/metabolismo , Colo/patologia , Sistema Nervoso Entérico/metabolismo , Sistema Nervoso Entérico/patologia , Humanos , Doenças Inflamatórias Intestinais/patologia , Células Intersticiais de Cajal/metabolismo , Células Intersticiais de Cajal/patologia , Masculino , Contração Muscular/genética , Contração Muscular/fisiologia , Músculo Liso Vascular/efeitos dos fármacos , Neuroglia/metabolismo , Neuroglia/patologia , Óxido Nítrico/metabolismo , Ratos , Receptor Tipo 1 de Angiotensina/genética , Receptor Tipo 2 de Angiotensina/genética , Transmissão Sináptica/genética
7.
Neuroimage ; 221: 117153, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32659351

RESUMO

Hysteresis is a well-known phenomenon in physics that relates changes in a system with its prior history. It is also part of human visual experience (perceptual hysteresis), and two different neural mechanisms might explain it: persistence (a cause of positive hysteresis), which forces to keep a current percept for longer, and adaptation (a cause of negative hysteresis), which in turn favors the switch to a competing percept early on. In this study, we explore the neural correlates underlying these mechanisms and the hypothesis of their competitive balance, by combining behavioral assessment with fMRI. We used machine learning on the behavioral data to distinguish between positive and negative hysteresis, and discovered a neural correlate of persistence at a core region of the ventral attention network, the anterior insula. Our results add to the understanding of perceptual multistability and reveal a possible mechanistic explanation for the regulation of different forms of perceptual hysteresis.


Assuntos
Adaptação Fisiológica/fisiologia , Córtex Cerebral/fisiologia , Neuroimagem Funcional , Aprendizado de Máquina , Rede Nervosa/fisiologia , Percepção Visual/fisiologia , Adulto , Córtex Cerebral/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Percepção de Movimento/fisiologia , Rede Nervosa/diagnóstico por imagem , Adulto Jovem
8.
Platelets ; 31(4): 541-543, 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-31516057

RESUMO

Thrombocytopenia is a clinically important condition that can lead to several problems when not correctly diagnosed. A decrease of platelet counts due to an in vitro phenomenon, Pseudothrombocytopenia, can be misunderstood and unnecessarily treated. The present case study describes a 57-year-old male with a history of pancreas adenocarcinoma and a current Staphylococcus aureus infection without any signs or symptoms that could explain the low levels of platelets obtained after blood analysis. Blood smear evaluation detected both platelet satellitism and phagocytosis by neutrophils. As this sample was anticoagulated with ethylenediaminetetraacetic acid (EDTA), a new blood sample with citrate was analyzed. Platelet count was normal and no morphological abnormalities were detected. This case emphasizes the need for considering not only laboratory results but also the patient clinical information to guarantee the correct diagnosis and the best treatment possible.


Assuntos
Plaquetas/patologia , Neutrófilos/fisiologia , Fagocitose , Trombocitopenia/diagnóstico , Anemia/sangue , Autoanticorpos/sangue , Coagulação Sanguínea/efeitos dos fármacos , Plaquetas/citologia , Plaquetas/metabolismo , Citratos/química , Ácido Edético/química , Humanos , Masculino , Pessoa de Meia-Idade , Agregação Plaquetária , Contagem de Plaquetas
9.
J Vis ; 20(8): 19, 2020 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-32805042

RESUMO

The human visual system is constantly processing multiple and often conflicting sensory cues to make perceptual decisions. Given the nonlinear nature of emotion recognition, this often leads to different percepts of the same physical facial expression. Moreover, the state of the emotion recognition system might depend on the trajectory of temporal context, potentially leading to a phenomenon known as perceptual hysteresis. Here, we aimed to explore temporal context-related mechanisms underlying perceptual hysteresis during emotion recognition. We hypothesized that dependence on recent perceptual experience might reveal important clues about the role of short-term memory on the perception of emotional stimuli. Behavioral data were acquired using reality-based, changing emotion expressions morphed from a source to a target emotion with different valences, always passing through a neutral expression. Participants identified the onset and offset of what they perceived as the neutral expression interval. Our results showed that current perception of emotional expression is affected by recent temporal context, thus revealing perceptual hysteresis. We also found a relation between recent perceptual history effects and stimulus emotional Content: The positive valence of the stimulus emotional content appeared to abolish perceptual history effects, whereas negatively loaded stimuli induced clear short-term memory effects and positive hysteresis. Our findings show direct competition between recent perceptual experience and stimulus emotional content during decision making, which affects the formation of current percepts in emotion recognition.


Assuntos
Emoções/fisiologia , Expressão Facial , Percepção Visual/fisiologia , Adulto , Sinais (Psicologia) , Feminino , Humanos , Masculino , Memória de Curto Prazo/fisiologia , Adulto Jovem
10.
Nitric Oxide ; 82: 1-11, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30423454

RESUMO

We evaluated whether l-proline (Pro) supplementation improves redox status and nitric oxide (NO) bioavailability and prevents or delays angiotensin II (AngII)-induced hypertension. Male Sprague-Dawley rats were distributed to four experimental groups: Pro + AngII (Pro-Ang), Pro + Saline (Pro-Sal), Vehicle + AngII (Veh-Ang) and Veh + Saline (Veh-Sal). Pro solution (2 g.kg-1·day-1) or water (vehicle) were orally administered, from day 0 to day 21. AngII (200 ng.kg-1.min-1) or saline were infused (s.c.) from day 7 to day 21. Systolic blood pressure (SBP) was measured by the tail-cuff method. From day 20-21, animals were kept on metabolic cages for 24h-urine collection. On day 21, urine and blood were collected for further quantification of redox status biomarkers, NO-related markers (urinary nitrates and nitrites, U-NOx; plasma asymmetric dimethylarginine, P-ADMA), metabolic and renal parameters. Pro prevented the AngII-induced SBP rise [mean (95% CI), Day 19: Pro-AngII, 137 (131; 143) vs. Veh-AngII, 157 (151; 163) mm Hg, P < 0.001]. Pro-AngII rats also had increased values of U-NOx, systemic and urinary total antioxidant status (TAS), urinary H2O2 and plasma urea, as well as reduced P-ADMA and unaltered urinary isoprostanes. Plasma Pro was inversely correlated with P-ADMA (r = -0.52, p = 0.0009) and positively correlated with urinary TAS (r = 0.55, p = 0.0005) which, in turn, was inversely correlated with P-ADMA (r = -0.56, p = 0.0004). Furthermore, urinary H2O2 values decreased across P-ADMA tertiles (p for linear trend = 0.023). These results suggest that Pro reduces P-ADMA levels and improves redox status, thereby increasing NO bioavailability and counteracting the AngII-induced SBP rise. H2O2 and TAS modulation by Pro may contribute to the reduced P-ADMA concentration.


Assuntos
Angiotensina II/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Suplementos Nutricionais , Óxido Nítrico/metabolismo , Prolina/farmacologia , Animais , Disponibilidade Biológica , Hipertensão/induzido quimicamente , Hipertensão/tratamento farmacológico , Masculino , Prolina/administração & dosagem , Ratos , Ratos Sprague-Dawley
11.
Neuroimage ; 179: 540-547, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29964186

RESUMO

Visual adaptation describes the processes by which the visual system alters its operating properties in response to changes in the environment. It is one of the mechanisms controlling visual perceptual bistability - when two perceptual solutions are available - by controlling the duration of each percept. Moving plaids are an example of such ambiguity. They can be perceived as two surfaces sliding incoherently over each other or as a single coherent surface. Here, we investigated, using fMRI, whether activity in the human motion complex (hMT+), a region tightly related to the perceptual integration of visual motion, is modulated by distinct forms of visual adaptation to coherent or incoherent perception of moving plaids. Our hypothesis is that exposure to global coherent or incoherent moving stimuli leads to different levels of measurable adaptation, reflected in hMT+ activity. We found that the strength of the measured visual adaptation effect depended on whether subjects integrated (coherent percept) or segregated (incoherent percept) surface motion signals. Visual motion adaptation was significant both for coherent motion and globally incoherent surface motion. Although not as strong as to the coherent percept, visual adaptation due to the incoherent percept also affects hMT+. This shows that adaptation can contribute to regulate percept duration during visual bistability, with distinct weights, depending on the type of percept. Our findings suggest a link between bistability and adaptation mechanisms, both due to coherent and incoherent motion percepts, but in an asymmetric manner. These asymmetric adaptation weights have strong implications in models of perceptual decision and may explain asymmetry of perceptual interpretation periods.


Assuntos
Adaptação Fisiológica/fisiologia , Percepção de Movimento/fisiologia , Córtex Visual/fisiologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Estimulação Luminosa
12.
Pediatr Nephrol ; 32(8): 1411-1422, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28337615

RESUMO

BACKGROUND: We aimed to study the impact of obesity on urinary excretion of angiotensinogen (U-AGT) in prepubertal children, focusing on the duration of obesity and gender. Also, we aimed to evaluate whether plasma angiotensinogen (P-AGT) and hydrogen peroxide (H2O2) play a role in the putative association. METHODS: Cross-sectional evaluation of 305 children aged 8-9 years (160 normal weight, 86 overweight, and 59 obese). Anthropometric measurements and 24-h ambulatory blood pressure monitoring were performed. Angiotensinogen (AGT) was determined by a commercial enzyme-linked immunosorbent assay (ELISA) kit and H2O2 by a microplate fluorometric assay. RESULTS: U-AGT and P-AGT levels were similar across body mass index (BMI) groups and between sexes. However, boys who were overweight/obese since the age of 4 years presented lower levels of U-AGT compared with those of normal weight at the same age. In children who were overweight/obese since the age of 4, urinary H2O2 decreased with P-AGT. CONCLUSIONS: A higher duration of obesity was associated with decreased U-AGT in boys, thus reflecting decreased intrarenal activity of the renin-angiotensin system. Also, children with a longer duration of obesity showed an inverse association between urinary H2O2 and P-AGT. Future studies should address whether these results reflect an early compensatory mechanism to limit obesity-triggered renal dysfunction.


Assuntos
Angiotensinogênio/urina , Peróxido de Hidrogênio/urina , Rim/fisiopatologia , Obesidade/urina , Eliminação Renal , Tecido Adiposo/metabolismo , Angiotensinogênio/sangue , Monitorização Ambulatorial da Pressão Arterial , Índice de Massa Corporal , Criança , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Rim/metabolismo , Masculino , Sistema Renina-Angiotensina , Fatores Sexuais , Fatores de Tempo
13.
Eur J Clin Invest ; 46(1): 50-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26541603

RESUMO

INTRODUCTION: Myeloperoxidase (MPO), an enzyme linking obesity and cardiovascular (CV) risk in adults, has rarely been studied in young children and no studies assessed its association with renal function. We sought to explore a possible association between serum MPO levels, obesity, CV risk factors and renal function in prepubertal children. MATERIALS/METHODS: Cross-sectional evaluation of 309 children aged 8-9 years (161 normal weight, 148 overweight/obese), members of the birth cohort Generation I (Portugal). Anthropometrics (body mass index (BMI), waist-to-height ratio (WHtR) and % body fat mass (%BFM) by bioelectrical impedance analysis), 24-h ambulatory blood pressure monitoring and pulse wave velocity (PWV) were measured. Insulin resistance was estimated by the HOMA index (considering serum fasting glucose and insulin determinations). Serum MPO levels were assessed by immunoenzymatic assay. RESULTS: MPO levels were positively associated with obesity indices (BMI z-score, WHtR and %BFM). Higher MPO levels were associated with higher 24-h and night-time mean arterial pressure, with nondipping and with higher values of insulin resistance. In normal weight children, the endothelial function, as evaluated indirectly by PWV, was an independent predictor of MPO levels. In overweight/obese children, estimated glomerular filtration rate increased significantly across tertiles of MPO (Ptrend = 0·031) and this association held after adjustment for age, sex, neutrophil and monocyte counts and CV risk factors. CONCLUSIONS: Our results reinforce the role of MPO as a risk marker in obesity and related CV morbidities in young children. MPO levels associate with the dipping pattern and PWV and, among overweight/obese children, an association exists between MPO and renal function.


Assuntos
Pressão Sanguínea , Composição Corporal , Doenças Cardiovasculares/sangue , Taxa de Filtração Glomerular , Resistência à Insulina , Obesidade/sangue , Peroxidase/sangue , Tecido Adiposo , Glicemia/metabolismo , Monitorização Ambulatorial da Pressão Arterial , Doenças Cardiovasculares/epidemiologia , Criança , Estudos de Coortes , Estudos Transversais , Impedância Elétrica , Endotélio Vascular , Feminino , Humanos , Insulina/sangue , Masculino , Obesidade/epidemiologia , Sobrepeso/sangue , Sobrepeso/epidemiologia , Portugal/epidemiologia , Análise de Onda de Pulso , Fatores de Risco
14.
Br J Nutr ; 116(5): 805-15, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27480380

RESUMO

Oxidative stress and nitric oxide (NO) appear to represent important links between obesity and cardiovascular, metabolic and/or renal disease. We investigated whether oxidative stress and NO production/metabolism are increased in overweight and obese prepubertal children and correlate with cardiometabolic risk and renal function. We performed a cross-sectional evaluation of 313 children aged 8-9 years. Anthropometrics, 24-h ambulatory blood pressure, pulse wave velocity (PWV), insulin resistance (homoeostasis model assessment index (HOMA-IR)), inflammatory/metabolic biomarkers, estimated glomerular filtration rate (eGFR), plasma total antioxidant status (TAS), plasma and urinary isoprostanes (P-Isop, U-Isop), urinary hydrogen peroxide (U-H2O2), and plasma and urinary nitrates and nitrites (P-NOx, U-NOx) were compared among normal weight, overweight and obese groups, according to WHO BMI z-score reference. U-Isop were increased in the obese group, whereas U-NOx were increased in both overweight and obese children. U-Isop were positively correlated with U-H2O2, myeloperoxidase (MPO), high-sensitivity C-reactive protein, HOMA-IR and TAG. TAS correlated negatively with U-Isop and MPO and positively with PWV. HOMA-IR and U-H2O2 were associated with higher U-Isop, independently of BMI and eGFR, and total cholesterol and U-H2O2 were associated with U-NOx, independently of BMI, eGFR values and P-NOx concentration. In overweight and obese children, eGFR decreased across P-NOx tertiles (median: 139·3 (25th, 75th percentile 128·0, 146·5), 128·0 (25th, 75th percentile 121·5, 140·4), 129·5 (25th, 75th percentile 119·4, 138·3), P for linear trend=0·003). We conclude that oxidant status and NO are increased in relation to fat accumulation and, even in young children, they translate into higher values of cardiometabolic risk markers and affect renal function.


Assuntos
Doenças Cardiovasculares/etiologia , Nefropatias/etiologia , Doenças Metabólicas/etiologia , Óxido Nítrico/sangue , Obesidade/metabolismo , Estresse Oxidativo/fisiologia , Biomarcadores/sangue , Biomarcadores/urina , Índice de Massa Corporal , Criança , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Nefropatias/fisiopatologia , Masculino , Óxido Nítrico/metabolismo , Obesidade/complicações , Fatores de Risco
15.
Pediatr Nephrol ; 31(3): 455-64, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26482255

RESUMO

BACKGROUND: Fibrogenic cytokines are recognized as putative drivers of disease activity and histopathological deterioration in various kidney diseases. We compared urinary transforming growth factor ß1 (U-TGF-ß1) and endothelin 1 (U-ET-1) levels across body mass index classes and assessed their association with the level of urinary angiotensinogen (U-AGT), a biomarker of intrarenal renin-angiotensin-aldosterone system (RAAS). METHODS: The was a cross-sectional evaluation of 302 children aged 8-9 years. Ambulatory blood pressure (BP), insulin resistance (HOMA-IR), aldosterone level and renal function were evaluated. U-ET-1, U-TGF-ß1 and U-AGT levels were determined by immunoenzymatic methods. RESULTS: Obese children presented with the lowest levels of U-ET-1 and U-TGF-ß1, but the difference was only significant for U-ET-1. In obese children, the median levels of both U-ET-1 and U-TGF-ß1 tended to increase across tertiles (T1-T3) of U-AGT (U-ET-1: T1, 19.9 (14.2-26.3); T2, 32.5 (23.3-141.6); T3, 24.8 (18.7-51.5) ng/g creatinine, p = 0.007; U-TGF-ß1: T1, 2.2 (1.8-4.0); T2, 4.3 (2.7-11.7); T3, 4.9 (3.8-10.1) ng/g creatinine, p = 0.004]. In multivariate models, in the obese group, U-ET-1 was associated with HOMA-IR and aldosterone and U-AGT levels, and U-TGF-ß1 was associated with U-AGT levels and 24 h-systolic BP. CONCLUSIONS: Whereas the initial hypothesis of higher levels of urinary fibrogenic cytokines in obese children was not confirmed in our study, both TGF-ß1 and U-ET-1 levels were associated with U-AGT level, which likely reflects an early interplay between tissue remodeling and RAAS in obesity-related kidney injury.


Assuntos
Angiotensinogênio/urina , Endotelina-1/urina , Obesidade Infantil/urina , Fator de Crescimento Transformador beta1/urina , Adolescente , Fatores Etários , Biomarcadores/urina , Índice de Massa Corporal , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Obesidade Infantil/diagnóstico , Obesidade Infantil/fisiopatologia , Sistema Renina-Angiotensina , Urinálise
16.
Pediatr Nephrol ; 31(2): 279-88, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26420679

RESUMO

BACKGROUND: Most modifiable risk factors for high blood pressure (BP), such as obesity and salt intake, are imprinted in childhood and persist into adulthood. The aim of our study was to evaluate the intake of salt in children and to assess its impact on BP taking into account gender and nutritional status. METHODS: A total of 298 children aged 8-9 years were evaluated in a cross-sectional study. Anthropometric measurements and 24-h ambulatory monitoring were performed, and salt intake was determined by 24-h urinary sodium excretion. RESULTS: The average estimated salt intake among the entire cohort of children enrolled in the study was 6.5 ± 2.2 g/day, and it was significantly higher in boys than in girls (6.8 ± 2.4 vs. 6.1 ± 1.9 g/day, respectively; p = 0.018) and in overweight/obese children than in normal weight children (6.8 ± 2.4 vs. 6.1 ± 2.0 g/day, respectively; p = 0.006). Salt intake exceeded the upper limit of the US Dietary Reference Intake in 72% of children. Daytime systolic BP increased by 1.00 mmHg (95% confidence interval 0.40-1.59) per gram of daily salt intake in overweight/obese boys, but not in normal weight boys or in girls. CONCLUSIONS: Our results demonstrate an extremely high salt intake among 8- to 9-year-old Portuguese children. Higher salt intake was associated with higher systolic BP in boys, specifically in those who were overweight/obese. Longitudinal studies are needed to further evaluate the causal relationship between obesity and high BP and the mechanism by which salt intake modulates this relationship. Nonetheless, based on our results, we urge that dietary salt reduction interventions, along with measures to fight the global epidemic of obesity, be implemented as early in life as possible.


Assuntos
Pressão Sanguínea , Hipertensão/etiologia , Sobrepeso/complicações , Obesidade Infantil/complicações , Cloreto de Sódio na Dieta/administração & dosagem , Determinação da Pressão Arterial , Criança , Estudos Transversais , Feminino , Humanos , Hipertensão/fisiopatologia , Masculino , Fatores de Risco , Fatores Sexuais
17.
Eur J Clin Invest ; 44(6): 527-38, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24673112

RESUMO

BACKGROUND: Lipoxins (LXs) are proresolving and anti-inflammatory eicosanoids whose role in chronic heart failure (CHF) pathogenesis has never been investigated. This study evaluated levels of LXs in CHF patients, its relationship with disease severity and correlation with established CHF biomarkers. The effect of low-dose aspirin [acetylsalicylic acid (ASA)] on the levels of LXs was also studied. MATERIALS AND METHODS: Lipoxin A4 (LXA4 ), 15-epi-lipoxin A4 (15-epi-LXA4 ) and myeloperoxidase (MPO) concentration and activity were evaluated by immunoenzymatic and spectrophotometric assays in 34 CHF patients [New York Heart Association (NYHA) functional class I to IV]. B-type natriuretic peptide (BNP), troponin, myoglobin, C-reactive protein (CRP) and uric acid (UA) were also analyzed. RESULTS: Patients were stratified into mild-to-moderate CHF (NYHA, classes I and II) and severe CHF (NYHA classes III and IV). Severe patients had lower plasma LXA4 (0·262 ± 0·034 vs. 0·362 ± 0·039 ng/mL, P < 0·05) and decreased urinary 15-epi-LXA4 levels (2·28 ± 0·44 vs. 4·88 ± 1·03 µg/day, P < 0·05) besides exhibiting increased plasma BNP (1464 ± 442 vs. 555 ± 162 pg/mL, P < 0·05) and MPO activity (45·15 ± 11·56 vs. 15·90 ± 2·80 µmol/min/mg protein, P < 0·05). Plasma LXA4 was inversely correlated with BNP, troponin, myoglobin, CRP, UA and MPO activity. ASA treatment was associated with higher urinary excretion of 15-epi-LXA4 (7·70 ± 1·48 vs. 2·06 ± 0·30 µg/day, P < 0·05) in mild-to-moderate CHF patients and lower BNP levels in both groups. CONCLUSIONS: Higher severity of CHF is associated with reduced levels of LXs. Plasma LXA4 appears to be a valuable marker for risk stratification in CHF. Furthermore, the ASA-related increase in urinary 15-epi-LXA4 suggests enhanced renal synthesis of this eicosanoid and may represent a disregarded benefit of ASA.


Assuntos
Insuficiência Cardíaca/etiologia , Lipoxinas/metabolismo , Idoso , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/farmacologia , Aspirina/administração & dosagem , Aspirina/farmacologia , Biomarcadores/metabolismo , Doenças Cardiovasculares/etiologia , Doença Crônica , Feminino , Taxa de Filtração Glomerular/fisiologia , Humanos , Inflamação/fisiopatologia , Contagem de Leucócitos , Masculino , Peroxidase/metabolismo , Fatores de Risco
18.
J Pediatr Endocrinol Metab ; 37(1): 42-51, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38054937

RESUMO

OBJECTIVES: Gender-related differences in oxidative stress, nitric oxide bioavailability, and cardiometabolic risk factors were examined in a cross-sectional study involving 313 prepubertal children (8-9 years old) from the generation XXI birth-cohort. METHODS: Anthropometric measurements, cardiometabolic variables, and redox markers were assessed, including plasma and urinary isoprostanes (P-Isop, U-Isop), plasma total antioxidant status (P-TAS), serum myeloperoxidase (MPO), plasma and urinary nitrates and nitrites (P-NOX, U-NOX), and urinary hydrogen peroxide (U-H2O2). RESULTS: Girls showed higher levels of total/non-HDL cholesterol, triglycerides, and insulin resistance (HOMA-IR) compared to boys. Notably, U-H2O2 values were lower in girls. When stratifying by body mass index (BMI) and gender, both girls and boys exhibited higher MPO concentration and U-Isop values. Uric acid concentration was higher in overweight and obese girls than in normal weight girls, while no significant differences were observed among boys across BMI categories. Furthermore, U-NOX values differed only in boys, with higher levels observed in overweight and obese individuals compared to those with normal weight. Multivariate analysis, adjusted for age and BMI z-score, demonstrated inverse associations between U-H2O2 and pulse wave velocity values, as well as between U-NOX and total or non-HDL cholesterol, exclusively in boys. In girls, a positive association between U-Isop and HOMA-IR values was observed. CONCLUSIONS: In conclusion, gender differentially impacts oxidative stress, nitric oxide bioavailability, and cardiometabolic risk factors in prepubertal children. Prepubertal girls appear more susceptible to oxidative stress-induced metabolic dysfunction, while in boys, elevated levels of redox and nitric oxide bioavailability markers seem to provide protection against arterial stiffness and lipid homeostasis.


Assuntos
Doenças Cardiovasculares , Resistência à Insulina , Masculino , Criança , Feminino , Humanos , Sobrepeso/complicações , Sobrepeso/metabolismo , Fatores de Risco Cardiometabólico , Estudos Transversais , Óxido Nítrico , Análise de Onda de Pulso/efeitos adversos , Peróxido de Hidrogênio , Fatores de Risco , Insulina , Obesidade/complicações , Índice de Massa Corporal , Colesterol , Estresse Oxidativo , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia
19.
Cancer Nurs ; 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38417129

RESUMO

BACKGROUND: Exergames can be an appealing strategy that is integrated into post-abdominal surgery rehabilitation. OBJECTIVE: The aim of this study was to assess the effectiveness of exergame rehabilitation in improving independence in activities of daily living (ADLs) and patient balance after abdominal cancer surgery. METHODS: A randomized control-group study was carried out in an oncological hospital in Portugal. Seventy postoperative patients were included, and data collection took place between January 2023 and May 2023. The patients were randomly assigned to either an exergame rehabilitation program (n = 35) or a traditional rehabilitation program (n = 35). The assessed outcomes were the Barthel and Berg scales, and data collection occurred at 3 different time points: admission, 48 hours postoperatively, and on the seventh day after surgery. RESULTS: At the third assessment, a statistically significant difference was observed between the 2 groups for both indicators, ADLs and balance. CONCLUSIONS: There was an improvement in ADLs and balance in the exergames group. By the seventh day after surgery, the intervention group showed improvement in balance and ADLs compared with the control group. IMPLICATIONS FOR PRACTICE: The use of exergames can be a solution to the challenges of traditional rehabilitation methods after abdominal surgery for cancer for postoperative patients. This is the first study carried out in this specific population.

20.
Sci Rep ; 14(1): 6363, 2024 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-38493169

RESUMO

Inhibition is implicated across virtually all human experiences. As a trade-off of being very efficient, this executive function is also prone to many errors. Rodent and computational studies show that midbrain regions play crucial roles during errors by sending dopaminergic learning signals to the basal ganglia for behavioural adjustment. However, the parallels between animal and human neural anatomy and function are not determined. We scanned human adults while they performed an fMRI inhibitory task requiring trial-and-error learning. Guided by an actor-critic model, our results implicate the dorsal striatum and the ventral tegmental area as the actor and the critic, respectively. Using a multilevel and dimensional approach, we also demonstrate a link between midbrain and striatum circuit activity, inhibitory performance, and self-reported autistic and obsessive-compulsive subclinical traits.


Assuntos
Aprendizagem , Área Tegmentar Ventral , Adulto , Animais , Humanos , Área Tegmentar Ventral/fisiologia , Aprendizagem/fisiologia , Gânglios da Base , Corpo Estriado/fisiologia , Inibição Neural
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