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1.
Hum Brain Mapp ; 43(3): 955-973, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34716738

RESUMO

We wanted to verify the effect of combining multi-echo (ME) functional magnetic resonance imaging (fMRI) with slice acceleration in simultaneous multi-slice acquisition. The aim was to shed light on the benefits of multiple echoes for various acquisition settings, especially for levels of slice acceleration and flip angle. Whole-brain ME fMRI data were obtained from 26 healthy volunteers (using three echoes; seven runs with slice acceleration 1, 4, 6, and 8; and two different flip angles for each of the first three acceleration factors) and processed as single-echo (SE) data and ME data based on optimal combinations weighted by the contrast-to-noise ratio. Global metrics (temporal signal-to-noise ratio, signal-to-noise separation, number of active voxels, etc.) and local characteristics in regions of interest were used to evaluate SE and ME data. ME results outperformed SE results in all runs; the differences became more apparent for higher acceleration, where a significant decrease in data quality is observed. ME fMRI can improve the observed data quality metrics over SE fMRI for a wide range of accelerated fMRI acquisitions.


Assuntos
Mapeamento Encefálico/métodos , Córtex Cerebral/fisiologia , Globo Pálido/fisiologia , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Adulto , Córtex Cerebral/diagnóstico por imagem , Imagem Ecoplanar/métodos , Feminino , Globo Pálido/diagnóstico por imagem , Humanos , Masculino , Desempenho Psicomotor/fisiologia , Adulto Jovem
2.
J Neural Transm (Vienna) ; 129(3): 319-329, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35076779

RESUMO

The vertex has been used as a suitable control stimulation site in repetitive transcranial magnetic stimulation studies. The objectives of this study are (1) to assess cognitive performance (CP) after theta burst stimulation (TBS); (2) to evaluate whether clinically relevant cortical areas might be reached by vertex stimulation and how that might influence CP. Twenty young healthy subjects performed a cognitive task prior to and immediately after intermittent TBS (iTBS) and continuous TBS (cTBS) of two active cortical stimulation sites and the vertex. We used the Wilcoxon signed-rank test to compare the pre- and post-stimulation reaction times (RTs) and a mixed ANOVA analysis to evaluate the effect of the stimulation on changes in RTs. A three-dimensional finite-element model (FEM) was used to calculate the vertex TBS-induced electrical field (E-field) in the adjacent regions of interest (ROIs). Correlation analyses were performed between E-fields in the ROIs and cognitive outcomes. We found a significant effect only of the stimulation time factor (F (1,12) = 65.37, p < 0.001) on RT shortening, with no superiority of the active site stimulation compared to the vertex stimulation. In 73.5% of vertex TBS sessions, a significant E-field was induced in at least one ROI. We found a negative association between the magnitude of the iTBS-induced E-fields and RT changes (R = - 0.54, p = 0.04). TBS protocols may lead to changes in CP when applied over the craniometrically targeted vertex. We therefore suggest not using a conventional approach as a vertex targeting method.


Assuntos
Cabeça , Estimulação Magnética Transcraniana , Humanos , Tempo de Reação , Ritmo Teta , Estimulação Magnética Transcraniana/métodos
3.
J Neural Transm (Vienna) ; 129(8): 1023-1030, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35819634

RESUMO

White Matter Lesions (WML) are a radiological finding common in aged subjects. We explored the impact of WML on underlying neurodegenerative processes. We focused on the impact of WML on two neurodegenerative diseases with different pathology. In this cross-sectional study of 137 subjects (78 female, 59 men, mean age 67.2; 43-87 years), we compared WML in healthy controls (HC; n = 55), patients with Alzheimer's disease and amnestic Mild Cognitive Impairment (aMCI), and Parkinson's disease patients with normal cognition and with MCI. Subjects with AD and aMCI were treated as one group (n = 40), subjects with PD and PDMCI were another group (n = 42). MRI T2_FLAIR sequences were analyzed. WML were divided into periventricular (pWML) or subcortical (sWML) depending on their distance from the ventricles. Subjects from the AD + aMCI group, had a significantly greater volume of WML than both HC and the PD + PDMCI group. The volume of WML was greater in the PD + PDMCI than in HC but the difference was not significant. In AD + aMCI subjects, sWML and not pWML were related to a decrease in global cognitive functioning despite greater volume of pWML. In PD + PDMCI, pWML correlate with decline in executive functions and working memory. In HC, pWML correlated with the multidomain decrease corresponding with the aging. This points to a difference between normal aging and pathological aging due to AD and PD brain pathology. The WML location together with underlying disease related neurodegeneration may play a role in determining the effect of WML on cognition. Our results suggest that the impact of WML is not uniform in all patients; rather, their volume, location and cognitive effect may be disease-specific.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doenças do Sistema Nervoso , Doença de Parkinson , Substância Branca , Idoso , Doença de Alzheimer/complicações , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Cognição , Disfunção Cognitiva/complicações , Disfunção Cognitiva/etiologia , Estudos Transversais , Progressão da Doença , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Doença de Parkinson/complicações , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/patologia , Substância Branca/diagnóstico por imagem , Substância Branca/patologia
4.
Hum Brain Mapp ; 42(9): 2921-2930, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-33772952

RESUMO

Many methods applied to data acquired by various imaging modalities have been evaluated for their benefit in localizing lesions in magnetic resonance (MR) negative epilepsy patients. No approach has proven to be a stand-alone method with sufficiently high sensitivity and specificity. The presented study addresses the potential benefit of the automated fusion of results of individual methods in presurgical evaluation. We collected electrophysiological, MR, and nuclear imaging data from 137 patients with pharmacoresistant MR-negative/inconclusive focal epilepsy. A subgroup of 32 patients underwent surgical treatment with known postsurgical outcomes and histopathology. We employed a Gaussian mixture model to reveal several classes of gray matter tissue. Classes specific to epileptogenic tissue were identified and validated using the surgery subgroup divided into two disjoint sets. We evaluated the classification accuracy of the proposed method at a voxel-wise level and assessed the effect of individual methods. The training of the classifier resulted in six classes of gray matter tissue. We found a subset of two classes specific to tissue located in resected areas. The average classification accuracy (i.e., the probability of correct classification) was significantly higher than the level of chance in the training group (0.73) and even better in the validation surgery subgroup (0.82). Nuclear imaging, diffusion-weighted imaging, and source localization of interictal epileptic discharges were the strongest methods for classification accuracy. We showed that the automatic fusion of results can identify brain areas that show epileptogenic gray matter tissue features. The method might enhance the presurgical evaluations of MR-negative epilepsy patients.


Assuntos
Eletroencefalografia/métodos , Epilepsias Parciais/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Adulto , Feminino , Humanos , Masculino , Imagem Multimodal
5.
Brain Topogr ; 34(4): 504-510, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33783670

RESUMO

Arterial spin labeling (ASL) is an MRI technique measuring brain perfusion using magnetically labeled blood as a tracer. The clinical utility of ASL for presurgical evaluation in non-lesional epilepsy as compared with the quantitative analysis of interictal [18F] fluorodeoxyglucose PET (FDG-PET) was studied. In 10 patients (4 female; median age 29 years) who underwent a complete presurgical evaluation followed by surgical resection, the presurgical FDG-PET and ASL scans were compared with the resection masks using asymmetry index (AI) maps. The positive predictive value (PPV) and sensitivity (SEN), were calculated from the number of voxels inside the mask (true positive), and outside the mask (false positive). The comparison of the PPVs showed better PPV in 6 patients using ASL and in 2 patients with PET. SEN was better in 4 patients using ASL and in 5 patients with PET. According to the Wilcoxon signed rank test for PPV (p = 0.74) and for SEN (p = 0.43), these methods have similar predictive power. ASL is a useful method for presurgical evaluation in non-lesional epilepsy. The main benefits of ASL over PET are that it avoids radiation exposure for patients, and it offers lower costs, higher availability, and better time efficiency.


Assuntos
Epilepsias Parciais , Fluordesoxiglucose F18 , Adulto , Circulação Cerebrovascular , Epilepsias Parciais/diagnóstico por imagem , Epilepsias Parciais/cirurgia , Feminino , Humanos , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons , Marcadores de Spin
6.
Can J Physiol Pharmacol ; 99(9): 974-982, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33852806

RESUMO

Although the dichotomous classification of metabolic syndrome (MS) enables the classification of individuals as MS-free or presenting MS, it is inconvenient for assessing cardiometabolic risk in MS-free individuals. Continuous MS score allows for estimation of cardiometabolic burden even in MS-free subjects. We used the scores to estimate the proportion of MS-free subjects on high cardiometabolic risk. A total of 876 subjects (62% females) of Central European descent, aged 20-81 years, were included. International Diabetes Federation (IDF) criteria were employed to classify MS. Continuous scores were calculated. We used the receiver operating characteristics (ROC) analysis to estimate the cutoff value to determine the proportion of MS-free subjects on increased risk. Using the waist circumference, 38% of males and 23% of females presented MS. ROC area under the curves (90%-98%) showed an acceptable performance of both scores to classify the presence of MS. Up to 18% of MS-free males and up to 10% of females displayed continuous score ≥ the relevant cutoff point. The waist-to-height ratio performed similar results. Both continuous scores were proven credible for assessing cardiometabolic risk in MS-free subjects. Clinically, this is important for earlier intervention. Despite minor differences between waist circumference and waist-to-height ratio, it would be appropriate to objectify it using reference population. Novelty: The first study using Z-MSS/siMSS (population-specific Z-score/continuous score of MS) to estimate cardiometabolic risk in Slovak adults. A proportion of MS-free Slovak adults is on high cardiometabolic risk. Difference between using waist circumference and the waist-to-height ratio does not seem to be major in our cohort.


Assuntos
Fatores de Risco de Doenças Cardíacas , Síndrome Metabólica/etiologia , Circunferência da Cintura , Razão Cintura-Estatura , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
7.
Neural Plast ; 2021: 5594305, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34349797

RESUMO

Many cognitive functions, including working memory, are processed within large-scale brain networks. We targeted the right frontoparietal network (FPN) with one session of transcranial direct current stimulation (tDCS) in an attempt to modulate the cognitive speed of a visual working memory task (WMT) in 27 young healthy subjects using a double-blind crossover design. We further explored the neural underpinnings of induced changes by performing resting-state fMRI prior to and immediately after each stimulation session with the main focus on the interaction between a task-positive FPN and a task-negative default mode network (DMN). Twenty minutes of 2 mA anodal tDCS was superior to sham stimulation in terms of cognitive speed manipulation of a subtask with processing of objects and tools in unconventional views (i.e., the higher cognitive load subtask of the offline WMT). This result was linked to the magnitude of resting-state functional connectivity decreases between the stimulated FPN seed and DMN seeds. We provide the first evidence for the action reappraisal mechanism of object and tool processing. Modulation of cognitive speed of the task by tDCS was reflected by FPN-DMN cross-talk changes.


Assuntos
Lobo Frontal/diagnóstico por imagem , Memória de Curto Prazo/fisiologia , Lobo Parietal/diagnóstico por imagem , Adolescente , Adulto , Estudos Cross-Over , Método Duplo-Cego , Feminino , Lobo Frontal/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Lobo Parietal/fisiopatologia , Tempo de Reação/fisiologia , Estimulação Transcraniana por Corrente Contínua , Adulto Jovem
8.
Eat Weight Disord ; 26(8): 2757-2761, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33559833

RESUMO

PURPOSE: People with eating disorders (EDs) have difficulties understanding their own emotions and recognizing the emotions of others, especially in ambiguous settings. We examined the neuronal mechanisms underlying the emotion processing of ambiguous interpersonal stimuli in EDs and healthy controls (HCs). METHODS: The fMRI data were acquired by a blocked experimental design with 28 women (14 EDs) during the visual presentation of a modified Thematic Apperception Test. RESULTS: EDs showed very strong associations between experienced and inferred emotions evoked by the stimuli; no such relationship was found in HCs. HCs displayed elevated left anterior insula activity during the mentalizing condition; EDs showed increased activity in the right supramarginal gyrus and medial prefrontal cortex. CONCLUSION: The two groups seem to apply different strategies for judging emotionally ambiguous stimuli, albeit resulting in equivalent judgments. We assume that activity in the supramarginal gyrus and insula in EDs is linked with suppressing their own perspective while considering emotional states, probably due to alexithymia and the lack of awareness of their own mental states. We hypothesize that the strong correlation between experienced and inferred emotions in EDs could reflect their tendency to use others as a reference point for perceiving themselves and gaining information about their affective state. LEVEL OF EVIDENCE: No level of evidence, this is a basic science study.


Assuntos
Transtornos da Alimentação e da Ingestão de Alimentos , Imageamento por Ressonância Magnética , Sintomas Afetivos , Emoções , Transtornos da Alimentação e da Ingestão de Alimentos/diagnóstico por imagem , Feminino , Humanos , Projetos Piloto
9.
Hum Brain Mapp ; 40(2): 699-712, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30431199

RESUMO

During social interactions, decision-making involves mutual reciprocity-each individual's choices are simultaneously a consequence of, and antecedent to those of their interaction partner. Neuroeconomic research has begun to unveil the brain networks underpinning social decision-making, but we know little about the patterns of neural connectivity within them that give rise to reciprocal choices. To investigate this, the present study measured the behaviour and brain function of pairs of individuals (N = 66) whilst they played multiple rounds of economic exchange comprising an iterated ultimatum game. During these exchanges, both players could attempt to maximise their overall monetary gain by reciprocating their opponent's prior behaviour-they could promote generosity by rewarding it, and/or discourage unfair play through retaliation. By adapting a model of reciprocity from experimental economics, we show that players' choices on each exchange are captured accurately by estimating their expected utility (EU) as a reciprocal reaction to their opponent's prior behaviour. We then demonstrate neural responses that map onto these reciprocal choices in two brain regions implicated in social decision-making: right anterior insula (AI) and anterior/anterior-mid cingulate cortex (aMCC). Finally, with behavioural Dynamic Causal Modelling, we identified player-specific patterns of effective connectivity between these brain regions with which we estimated each player's choices with over 70% accuracy; namely, bidirectional connections between AI and aMCC that are modulated differentially by estimates of EU from our reciprocity model. This input-state-output modelling procedure therefore reveals systematic brain-behaviour relationships associated with the reciprocal choices characterising interactive social decision-making.


Assuntos
Córtex Cerebral/fisiologia , Conectoma , Tomada de Decisões/fisiologia , Função Executiva/fisiologia , Relações Interpessoais , Rede Nervosa/fisiologia , Percepção Social , Adulto , Idoso , Córtex Cerebral/diagnóstico por imagem , Comportamento de Escolha/fisiologia , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/fisiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Adulto Jovem
10.
Brain Topogr ; 31(5): 767-779, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29693205

RESUMO

Parcellation-based approaches are an important part of functional magnetic resonance imaging data analysis. They are a necessary processing step for sorting data in structurally or functionally homogenous regions. Real functional magnetic resonance imaging datasets usually do not cover the atlas template completely; they are often spatially constrained due to the physical limitations of MR sequence settings, the inter-individual variability in brain shape, etc. When using a parcellation template, many regions are not completely covered by actual data. This paper addresses the issue of the area coverage required in real data in order to reliably estimate the representative signal and the influence of this kind of data loss on network analysis metrics. We demonstrate this issue on four datasets using four different widely used parcellation templates. We used two erosion approaches to simulate data loss on the whole-brain level and the ROI-specific level. Our results show that changes in ROI coverage have a systematic influence on network measures. Based on the results of our analysis, we recommend controlling the ROI coverage and retaining at least 60% of the area in order to ensure at least 80% of explained variance of the original signal.


Assuntos
Atlas como Assunto , Mapeamento Encefálico/métodos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Adulto , Algoritmos , Encéfalo/diagnóstico por imagem , Simulação por Computador , Feminino , Lateralidade Funcional , Voluntários Saudáveis , Humanos , Individualidade , Modelos Lineares , Imageamento por Ressonância Magnética/estatística & dados numéricos , Masculino , Estimulação Luminosa , Reprodutibilidade dos Testes , Adulto Jovem
11.
J Electrocardiol ; 51(6): 1085-1089, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30497735

RESUMO

Both obesity and menopause are significant cardiovascular risk factors. In postmenopausal women the protective effect of estrogens is reduced and menopause is frequently associated with occurrence of other significant cardiovascular factors including obesity. This study was focused on evaluating the effect of obesity on the QRS complex in pre- and postmenopausal women. We present results of analysis of 199 electrocardiograms of pre- and postmenopausal women analyzed in relation to the body mass index within normal limits (BMI 20 to 24.9 kg/m2) and obesity (BMI > 30 kg/m2), respectively. Obesity in premenopausal women and menopause significantly affected both the electrical axis (EA) and maximum QRS spatial vector magnitude (QRSmax). The highest QRSmax and electrical axis values were observed in premenopausal lean women, and they were significantly higher as than in the premenopausal obese women, postmenopausal lean and obese women (QRSmax: 1.66 ±â€¯0.4 mV, 1.17 ±â€¯0.35 mV, 1.4 ±â€¯0.46 mV, and 1.35 ±â€¯0.39 mV, resp.). (EA: 56.4 ±â€¯18.0°, 38.22 ±â€¯18.38°, 45.82 ±â€¯18.63°, and 36.75 ±â€¯17.51°). The differences between obese premenopausal women, lean and obese postmenopausal women were not statistically significant. These differences were reflected in 12-lead ECG amplitude. The presence of additional cardiovascular risk factors did not affect the ECG parameters. Obesity significantly affected QRS complex in premenopausal women. This effect was comparable with the effect of menopause. Because all QRS complex changes were within normal limits, these results suggest that ECG evaluation in women should go beyond traditional diagnostic categories and consider the relationship between ECG changes and two cardiovascular risk factors - obesity and menopause.


Assuntos
Eletrocardiografia , Obesidade/fisiopatologia , Pós-Menopausa/fisiologia , Pré-Menopausa/fisiologia , Adulto , Idoso , Índice de Massa Corporal , Doenças Cardiovasculares , Feminino , Humanos , Pessoa de Meia-Idade , Fatores de Risco
12.
Neural Plast ; 2018: 3106918, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29725346

RESUMO

We examined effects of theta burst stimulation (TBS) applied over two distinct cortical areas (the right inferior frontal gyrus and the left superior parietal lobule) on the Stroop task performance in 20 young healthy subjects. Neural underpinnings of the behavioral effect were tested using fMRI. A single session of intermittent TBS of the left superior parietal lobule induced certain cognitive speed enhancement and significantly increased resting-state connectivity of the dorsal attention network. This is an exploratory study that prompts further research with multiple-session TBS in subjects with cognitive impairment.


Assuntos
Atenção/fisiologia , Rede Nervosa/fisiologia , Lobo Parietal/fisiologia , Ritmo Teta/fisiologia , Estimulação Magnética Transcraniana/métodos , Adulto , Feminino , Voluntários Saudáveis , Humanos , Masculino , Desempenho Psicomotor/fisiologia , Distribuição Aleatória , Teste de Stroop , Adulto Jovem
13.
Cent Eur J Public Health ; 26(3): 228-233, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30419627

RESUMO

OBJECTIVES: Central obesity represents an increased risk to develop cardiovascular diseases. Guidelines of international societies suggest estimating central obesity by measuring waist circumference (WC). Robust statistical data in literature provide evidence on the superiority of waist-to-height ratio (WHtR) over WC and body mass index (BMI) for detecting cardiometabolic risk in both genders. Based on measurements of weight, height and waist circumference we compared the prevalence of central obesity using both the above mentioned criteria in the apparently healthy Slovak adults, and compared the prevalence of central obesity to that of general obesity (BMI). METHODS: Data collected from 5,184 individuals (45% males) aged ≥18 years in four cross-sectional studies carried out between the years 2009-2012 were subjected to secondary analysis. RESULTS: Waist circumference underestimated central obesity in males and overestimated in females: 37.3% of males and 41.8% of females presented central obesity according to WC, 54.2% males and 34.9% females according to WHtR. 17.3% of males centrally obese according to WC present WHtR < 0.5; while 7.8% of females centrally obese according to their WHtR do not display increased WC. The frequency of central obesity increased with age. According to BMI, the prevalence of overweight was 39% in males and 22% in females; that of obesity was 17% and 15%, respectively. CONCLUSION: The prevalence of central obesity estimated using WC vs. WHtR differs significantly in Slovak adults. WHtR is considered superior for detection of the risk of future development of cardiovascular afflictions. Thus, further studies addressing the gender-associated discordance of central obesity measures are required to determine whether our results are consistent across geographical regions and ethnic groups.


Assuntos
Obesidade/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antropometria , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade Abdominal/epidemiologia , Prevalência , Fatores Sexuais , Eslováquia/epidemiologia , Circunferência da Cintura , Razão Cintura-Estatura
14.
Clin Chem Lab Med ; 52(1): 139-49, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23509221

RESUMO

BACKGROUND: Interaction of advanced glycation end products (AGEs) with their specific cell-surface receptor for AGEs (RAGE) induces production of reactive oxygen species, pro-diabetic, pro-inflammatory, and pro-atherogenic responses. The metabolic syndrome (Metsy) imposes a high risk of development of cardiovascular disease and unequivocally predisposes the non-diabetics to type 2 diabetes mellitus. The aim of the study was to investigate the association between circulating soluble RAGE (sRAGE), Nε-(carboxymethyl)lysine (CML) or AGE-associated fluorescence of plasma (AGE-Fl) with the number of manifested Metsy risk factors in young-to-middle-aged medication-free non-diabetic subjects. METHODS: Metsy was classified according to NCEP/ATP III criteria; plasma sRAGE and total CML were determined by ELISA methods and AGE-Fl fluorimetrically. RESULTS: From among 437 participants aged 33±11 years, 58% were females. In total 174 subjects were Metsy risk factors-free, 142 presented one, 59 presented two risk factors, and 62 suffered from Metsy. Plasma sRAGE and CML/albumin levels decreased with increasing number of Metsy risk factors (p<0.01, both), while AGE-Fl/albumin levels remained similar. Multivariate analysis selected waist circumference as a main determinant of plasma sRAGE as well as CML/albumin levels. CONCLUSIONS: In young-to-middle-aged non-diabetic medication-free subjects plasma total CML/albumin and sRAGE levels decrease prior to the manifestation of Metsy. With regards to RAGE-mediated CML trapping into adipose tissue inducing dysregulation of pro-inflammatory cytokines, adipokines, and the development of obesity-related insulin resistance, and the potential involvement of sRAGE in feedback regulation of the toxic effects of AGE/RAGE-mediated signaling, this early decline might be of clinical impact in development of type 2 diabetes and its complications.


Assuntos
Lisina/análogos & derivados , Síndrome Metabólica/etiologia , Receptores Imunológicos/sangue , Adolescente , Adulto , Idoso , Estudos de Coortes , Feminino , Produtos Finais de Glicação Avançada/sangue , Humanos , Lisina/sangue , Masculino , Síndrome Metabólica/sangue , Pessoa de Meia-Idade , Receptor para Produtos Finais de Glicação Avançada , Fatores de Risco , Albumina Sérica/análise , Adulto Jovem
15.
Croat Med J ; 55(3): 218-27, 2014 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-24891280

RESUMO

AIM: To estimate the impact of high fat diet and estrogen deficiency on the oxidative and antioxidative status in the liver of the ovariectomized rats, as well as the ameliorating effect of physical activity or consumption of functional food containing bioactive compounds with antioxidative properties on oxidative damage in the rat liver. METHODS: The study was conducted from November 2012 to April 2013. Liver oxidative damage was determined by lipid peroxidation levels expressed in terms of thiobarbituric acid reactive substances (TBARS), while liver antioxidative status was determined by catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST), glutathione reductase (GR) activities, and glutathione (GSH) content. Sixty-four female Wistar rats were divided into eight groups: sham operated and ovariectomized rats that received either standard diet, high fat diet, or high fat diet supplemented with cereal selenized onion biscuits or high fat diet together with introduction of physical exercise of animals. RESULTS: High fat diet significantly increased TBARS content in the liver compared to standard diet (P=0.032, P=0.030). Furthermore, high fat diet decreased the activities of CAT, GR, and GST, as well as the content of GSH (P<0.050). GPx activity remained unchanged in all groups. Physical activity and consumption of cereal selenized onion biscuits showed protective effect through increased GR activity in sham operated rats (P=0.026, P=0.009), while in ovariectomized group CAT activity was increased (P=0.018) in rats that received cereal selenized onion biscuits. CONCLUSION: Feeding rats with high fat diet was accompanied by decreased antioxidative enzyme activities and increased lipid peroxidation. Bioactive compounds of cereal selenized onion biscuits showed potential to attenuate the adverse impact of high fat diet on antioxidative status.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Glutationa/metabolismo , Fígado/efeitos dos fármacos , Atividade Motora/fisiologia , Ovariectomia , Ovário/fisiologia , Oxirredutases/metabolismo , Animais , Antioxidantes/metabolismo , Feminino , Peroxidação de Lipídeos , Fígado/enzimologia , Oxirredução , Condicionamento Físico Animal , Ratos , Ratos Wistar , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
16.
Croat Med J ; 55(3): 228-38, 2014 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-24891281

RESUMO

AIM: To evaluate in a rat animal model whether ovariectomy, high fat diet (HFD), and physical activity in the form of running affect leptin receptor (Ob-R) distribution in the brain and white fat tissue compared to sham (Sh) surgery, standard diet (StD), and sedentary conditions. METHODS: The study included 48 female laboratory Wistar rats (4 weeks old). Following eight weeks of feeding with standard or HFD, rats were subjected to either OVX or Sh surgery. After surgery, all animals continued StD or HFD for the next 10 weeks. During these 10 weeks, ovariectomy and Sh groups were subjected to physical activity or sedentary conditions. Free-floating immunohistochemistry and Western blot methods were carried out to detect Ob-R in the brain and adipose tissue. RESULTS: StD-ovariectomy-sedentary group had a greater number of Ob-R positive neurons in lateral hypothalamic nuclei than StD-Sh-sedentary group. There was no difference in Ob-R positive neurons in arcuatus nuclei between all groups. Ob-R distribution in the barrel cortex was higher in HFD group than in StD group. Ob-R presence in perirenal and subcutaneous fat was decreased in StD-ovariectomy group. CONCLUSION: HFD and ovariectomy increased Ob-R distribution in lateral hypothalamic nuclei, but there was no effect on arcuatus nuclei. Our results are first to suggest that HFD, ovariectomy, and physical activity affect Ob-R distribution in the barrel cortex, which might be correlated with the role of Ob-R in election of food in rats.


Assuntos
Tecido Adiposo Branco/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Dieta Hiperlipídica , Gorduras na Dieta/administração & dosagem , Atividade Motora/fisiologia , Ovariectomia , Receptores para Leptina/metabolismo , Tecido Adiposo Branco/metabolismo , Animais , Western Blotting , Peso Corporal/efeitos dos fármacos , Encéfalo/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Ovário/fisiologia , Ratos , Ratos Wistar
17.
Parkinsonism Relat Disord ; 121: 106031, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38364623

RESUMO

BACKGROUND: Functional connectivity changes in clinically overt neurodegenerative diseases such as dementia with Lewy bodies have been described, but studies on connectivity changes in the pre-dementia phase are scarce. OBJECTIVES: We concentrated on evaluating striato-cortical functional connectivity differences between patients with Mild Cognitive Impairment with Lewy bodies and healthy controls and on assessing the relation to cognition. METHODS: Altogether, we enrolled 77 participants (47 patients, of which 35 met all the inclusion criteria for the final analysis, and 30 age- and gender-matched healthy controls, of which 28 met all the inclusion criteria for the final analysis) to study the seed-based connectivity of the dorsal, middle, and ventral striatum. We assessed correlations between functional connectivity in the regions of between-group differences and neuropsychological scores of interest (visuospatial and executive domains z-scores). RESULTS: Subjects with Mild Cognitive Impairment with Lewy Bodies, as compared to healthy controls, showed increased connectivity from the dorsal part of the striatum particularly to the bilateral anterior part of the temporal cortex with an association with executive functions. CONCLUSIONS: We were able to capture early abnormal connectivity within cholinergic and noradrenergic pathways that correlated with cognitive functions known to be linked to cholinergic/noradrenergic deficits. The knowledge of specific alterations may improve our understanding of early neural changes in pre-dementia stages and enhance research of disease modifying therapy.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doença por Corpos de Lewy , Humanos , Doença por Corpos de Lewy/complicações , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/complicações , Cognição , Função Executiva , Colinérgicos/metabolismo , Doença de Alzheimer/metabolismo , Encéfalo/metabolismo
18.
Front Aging Neurosci ; 15: 1117473, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36967818

RESUMO

Parkinson's disease (PD) affects the language processes, with a significant impact on the patients' daily communication. We aimed to describe specific alterations in the comprehension of syntactically complex sentences in patients with PD (PwPD) as compared to healthy controls (HC) and to identify the neural underpinnings of these deficits using a functional connectivity analysis of the striatum. A total of 20 patients PwPD and 15 HC participated in the fMRI study. We analyzed their performance of a Test of sentence comprehension (ToSC) adjusted for fMRI. A task-dependent functional connectivity analysis of the striatum was conducted using the psychophysiological interaction method (PPI). On the behavioral level, the PwPD scored significantly lower (mean ± sd: 77.3 ± 12.6) in the total ToSC score than the HC did (mean ± sd: 86.6 ± 8.0), p = 0.02, and the difference was also significant specifically for sentences with a non-canonical word order (PD-mean ± sd: 69.9 ± 14.1, HC-mean ± sd: 80.2 ± 11.5, p = 0.04). Using PPI, we found a statistically significant difference between the PwPD and the HC in connectivity from the right striatum to the supplementary motor area [SMA, (4 8 53)] for non-canonical sentences. This PPI connectivity was negatively correlated with the ToSC accuracy of non-canonical sentences in the PwPD. Our results showed disturbed sentence reading comprehension in the PwPD with altered task-dependent functional connectivity from the right striatum to the SMA, which supports the synchronization of the temporal and sequential aspects of language processing. The study revealed that subcortical-cortical networks (striatal-frontal loop) in PwPD are compromised, leading to impaired comprehension of syntactically complex sentences.

19.
J Electrocardiol ; 45(3): 244-51, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22520960

RESUMO

OBJECTIVE: This study was undertaken to evaluate the nature and onset of changes in the QRS complex in the offspring of patients with diabetes mellitus (DM) and metabolic syndrome (MetS). METHODS AND METHODS: A total of 529 subjects, divided into 5 groups, were included in the study: (i) group DM (n = 92), patients with DM; (ii) group MetS (n = 125), patients with MetS; (iii) group O-DM (n = 109), offspring of patients with DM; (iv) group O-MetS (n = 122), offspring of patients with MetS; and (v) group HO (n = 81), offspring of healthy subjects. QRS parameters analyzed included amplitude, maximum QRS spatial vector magnitude, electrical axis (EA), and 3 electrocardiogram (ECG) criteria for left ventricular hypertrophy based on amplitude criteria: Sokolow-Lyon index, Cornell voltage, and Gubner criterion. RESULTS: Patients with DM and MetS showed a significant leftward shift of the EA when compared with the control group. A modest but significant leftward shift of EA was also observed in both offspring groups. These EA and maximum QRS spatial vector magnitude changes were reflected in the individual leads of the 12-lead ECG. The prevalence of a positive diagnosis by accepted electrocardiographic criteria (ECG left ventricular hypertrophy) was low. CONCLUSION: Patients with DM and MetS displayed significant changes in QRS complex that suggest depolarization sequence deterioration. Similar changes were observed also in the offspring of patients with DM and MetS, which suggests early subclinical cardiovascular damage. These findings have implications for prevention, early diagnosis, and treatment in the offspring of patients with DM and MetS.


Assuntos
Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/genética , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/genética , Eletrocardiografia/estatística & dados numéricos , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/genética , Adolescente , Adulto , Distribuição por Idade , Idoso , Arritmias Cardíacas/epidemiologia , Diabetes Mellitus/diagnóstico , Diagnóstico Precoce , Feminino , Predisposição Genética para Doença/epidemiologia , Predisposição Genética para Doença/genética , Humanos , Masculino , Síndrome Metabólica/diagnóstico , Pessoa de Meia-Idade , Distribuição por Sexo , Eslováquia/epidemiologia , Adulto Jovem
20.
Sci Rep ; 12(1): 20754, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36456622

RESUMO

Transcranial direct current stimulation (tDCS) has the potential to modulate cognitive training in healthy aging; however, results from various studies have been inconsistent. We hypothesized that inter-individual differences in baseline brain state may contribute to the varied results. We aimed to explore whether baseline resting-state dynamic functional connectivity (rs-dFC) and/or conventional resting-state static functional connectivity (rs-sFC) may be related to the magnitude of cognitive aftereffects of tDCS. To achieve this aim, we used data from our double-blind randomized sham-controlled cross-over tDCS trial in 25 healthy seniors in which bifrontal tDCS combined with cognitive training had induced significant behavioral aftereffects. We performed a backward regression analysis including rs-sFC/rs-dFC measures to explain the variability in the magnitude of tDCS-induced improvements in visual object-matching task (VOMT) accuracy. Rs-dFC analysis revealed four rs-dFC states. The occurrence rate of a rs-dFC state 4, characterized by a high correlation between the left fronto-parietal control network and the language network, was significantly associated with tDCS-induced VOMT accuracy changes. The rs-sFC measure was not significantly associated with the cognitive outcome. We show that flexibility of the brain state representing readiness for top-down control of object identification implicated in the studied task is linked to the tDCS-enhanced task accuracy.


Assuntos
Estimulação Transcraniana por Corrente Contínua , Humanos , Individualidade , Progressão da Doença , Encéfalo , Cognição
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