Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 177
Filtrar
1.
J Rehabil Med ; 56: jrm18253, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38450442

RESUMEN

OBJECTIVE: To examine the clinical effects of combining motor imagery-based neurofeedback training with bilateral repetitive transcranial magnetic stimulation for upper limb motor function in subacute and chronic stroke. DESIGN: Clinical trial following an AB/BA crossover design with counterbalanced assignment. SUBJECTS: Twenty individuals with subacute (n = 4) or chronic stroke (n = 16). METHODS: Ten consecutive sessions of bilateral repetitive transcranial magnetic stimulation alone (therapy A) were compared vs a combination of10 consecutive sessions of bilateral repetitive transcranial magnetic stimulation with 12 non-consecutive sessions of motor imagery-based neurofeedback training (therapy B). Patients received both therapies (1-month washout period), in sequence AB or BA. Participants were assessed before and after each therapy and at 15-days follow-up, using the Fugl-Meyer Assessment-upper limb, hand-grip strength, and the Nottingham Sensory Assessment as primary outcome measures. RESULTS: Both therapies resulted in improved functionality and sensory function. Therapy B consistently exhibited superior effects compared with therapy A, according to Fugl-Meyer Assessment and tactile and kinaesthetic sensory function across multiple time-points, irrespective of treatment sequence. No statistically significant differences between therapies were found for hand-grip strength. CONCLUSION: Following subacute and chronic stroke, integrating bilateral repetitive transcranial magnetic stimulation and motor imagery-based neurofeedback training has the potential to enhance functional performance compared with using bilateral repetitive transcranial magnetic stimulation alone in upper limb recovery.


Asunto(s)
Neurorretroalimentación , Accidente Cerebrovascular , Humanos , Estudios Cruzados , Fuerza de la Mano , Accidente Cerebrovascular/complicaciones , Estimulación Magnética Transcraneal , Extremidad Superior
2.
Magn Reson Med ; 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38502108

RESUMEN

PURPOSE: Arterial spin labeling (ASL) is a widely used contrast-free MRI method for assessing cerebral blood flow (CBF). Despite the generally adopted ASL acquisition guidelines, there is still wide variability in ASL analysis. We explored this variability through the ISMRM-OSIPI ASL-MRI Challenge, aiming to establish best practices for more reproducible ASL analysis. METHODS: Eight teams analyzed the challenge data, which included a high-resolution T1-weighted anatomical image and 10 pseudo-continuous ASL datasets simulated using a digital reference object to generate ground-truth CBF values in normal and pathological states. We compared the accuracy of CBF quantification from each team's analysis to the ground truth across all voxels and within predefined brain regions. Reproducibility of CBF across analysis pipelines was assessed using the intra-class correlation coefficient (ICC), limits of agreement (LOA), and replicability of generating similar CBF estimates from different processing approaches. RESULTS: Absolute errors in CBF estimates compared to ground-truth synthetic data ranged from 18.36 to 48.12 mL/100 g/min. Realistic motion incorporated into three datasets produced the largest absolute error and variability between teams, with the least agreement (ICC and LOA) with ground-truth results. Fifty percent of the submissions were replicated, and one produced three times larger CBF errors (46.59 mL/100 g/min) compared to submitted results. CONCLUSIONS: Variability in CBF measurements, influenced by differences in image processing, especially to compensate for motion, highlights the significance of standardizing ASL analysis workflows. We provide a recommendation for ASL processing based on top-performing approaches as a step toward ASL standardization.

3.
MAGMA ; 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38393541

RESUMEN

OBJECTIVE: Diffusional kurtosis imaging (DKI) extends diffusion tensor imaging (DTI), characterizing non-Gaussian diffusion effects but requires longer acquisition times. To ensure the robustness of DKI parameters, data acquisition ordering should be optimized allowing for scan interruptions or shortening. Three methodologies were used to examine how reduced diffusion MRI scans impact DKI histogram-metrics: 1) the electrostatic repulsion model (OptEEM); 2) spherical codes (OptSC); 3) random (RandomTRUNC). MATERIALS AND METHODS: Pre-acquired diffusion multi-shell data from 14 female healthy volunteers (29±5 years) were used to generate reordered data. For each strategy, subsets containing different amounts of the full dataset were generated. The subsampling effects were assessed on histogram-based DKI metrics from tract-based spatial statistics (TBSS) skeletonized maps. To evaluate each subsampling method on simulated data at different SNRs and the influence of subsampling on in vivo data, we used a 3-way and 2-way repeated measures ANOVA, respectively. RESULTS: Simulations showed that subsampling had different effects depending on DKI parameter, with fractional anisotropy the most stable (up to 5% error) and radial kurtosis the least stable (up to 26% error). RandomTRUNC performed the worst while the others showed comparable results. Furthermore, the impact of subsampling varied across distinct histogram characteristics, the peak value the least affected (OptEEM: up to 5% error; OptSC: up to 7% error) and peak height (OptEEM: up to 8% error; OptSC: up to 11% error) the most affected. CONCLUSION: The impact of truncation depends on specific histogram-based DKI metrics. The use of a strategy for optimizing the acquisition order is advisable to improve DKI robustness to exam interruptions.

4.
Neurol Sci ; 45(3): 1201-1208, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37847419

RESUMEN

OBJECTIVE: To investigate the neural correlates of working memory during a spontaneous migraine attack compared to the interictal phase, using functional magnetic resonance imaging (fMRI). BACKGROUND: Cognitive disturbances are commonly observed during migraine attacks, particularly in the headache phase. However, the neural basis of these changes remains unknown. METHODS: In a fMRI within-subject test-retest design study, eleven women (32 years of age, average) with episodic migraine were evaluated twice, first during a spontaneous migraine attack, and again in a pain-free period. Each session consisted in a cognitive assessment and fMRI while performing a working memory task (N-back). RESULTS: Cognitive test scores were lower during the ictal session than in the pain-free session. Regions typically associated with working memory were activated during the N-back task in both sessions. A voxel wise between session comparison showed significantly greater activation in the left frontal pole and orbitofrontal cortex during the attack relative to the interictal phase. CONCLUSION: Migraine patients exhibited greater activation of the left frontal pole and orbitofrontal cortex while executing a verbal working memory task during a spontaneous migraine attack when compared to the interictal state. Given the association of these regions with pain processing and inhibitory control, these findings suggest that patients recruit inhibitory areas to accomplish the cognitive task during migraine attacks, a neural signature of their cognitive difficulties.


Asunto(s)
Imagen por Resonancia Magnética , Trastornos Migrañosos , Humanos , Femenino , Memoria a Corto Plazo , Trastornos Migrañosos/diagnóstico por imagen , Cefalea , Corteza Prefrontal
5.
Antioxidants (Basel) ; 12(12)2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-38136171

RESUMEN

Nanomedicine's advent has promised to revolutionize different biomedical fields, including oncology. Silver Nanoparticles (AgNPs) showed promising results in different tumor models. Clear cell Renal Cell Carcinoma (ccRCC) is especially challenging due to its late diagnosis, poor prognosis and treatment resistance. Therefore, defining new therapeutic targets and regimens could improve patient management. This study intends to evaluate AgNPs' effect in ccRCC cells and explore their potential combinatory effect with Everolimus and Radiotherapy. AgNPs were synthesized, and their effect was evaluated regarding their entering pathway, cellular proliferation capacity, ROS production, mitochondrial membrane depolarization, cell cycle analysis and apoptosis assessment. AgNPs were combined with Everolimus or used to sensitize cells to radiotherapy. AgNPs are cytotoxic to 786-O cells, a ccRCC cell line, entering through endocytosis, increasing ROS, depolarizing mitochondrial membrane, and blocking the cell cycle, leading to a reduction of proliferation capacity and apoptosis. Combined with Everolimus, AgNPs reduce cell viability and inhibit proliferation capacity. Moreover, 786-O is intrinsically resistant to radiation, but after AgNPs' administration, radiation induces cytotoxicity through mitochondrial membrane depolarization and S phase blockage. These results demonstrate AgNPs' cytotoxic potential against ccRCC and seem promising regarding the combination with Everolimus and sensitization to radiotherapy, which can, in the future, benefit ccRCC patients' management.

6.
BMC Complement Med Ther ; 23(1): 374, 2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-37872494

RESUMEN

BACKGROUND: Given the rising occurrence of antibiotic resistance due to the existence and ongoing development of resistant bacteria and phenotypes, the identification of new treatments and sources of antimicrobial agents is of utmost urgency. An important strategy for tackling bacterial resistance involves the utilization of drug combinations, and natural products derived from plants hold significant potential as a rich source of bioactive compounds that can act as effective adjuvants. This study, therefore, aimed to assess the antibacterial potential and the chemical composition of Miconia albicans, a Brazilian medicinal plant used to treat various diseases. METHODS: Ethanolic extracts from leaves and stems of M. albicans were obtained and subsequently partitioned to give the corresponding hexane, chloroform, ethyl acetate, and hydromethanolic phases. All extracts and phases had their chemical constitution investigated by HPLC-DAD-MS/MS and GC-MS and were assessed for their antibiofilm and antimicrobial efficacy against Staphylococcus aureus. Furthermore, their individual effects and synergistic potential in combination with antibiotics were examined against clinical strains of both S. aureus and Acinetobacter baumannii. In addition, 10 isolated compounds were obtained from the leaves phases and used for confirmation of the chemical profiles and for antibacterial assays. RESULTS: Based on the chemical profile analysis, 32 compounds were successfully or tentatively identified, including gallic and ellagic acid derivatives, flavonol glycosides, triterpenes and pheophorbides. Extracts and phases obtained from the medicinal plant M. albicans demonstrated synergistic effects when combined with the commercial antibiotics ampicillin and ciprofloxacin, against multi-drug resistant bacteria S. aureus and A. baumannii, restoring their antibacterial efficacy. Extracts and phases also exhibited antibiofilm property against S. aureus. Three key compounds commonly found in the samples, namely gallic acid, quercitrin, and corosolic acid, did not exhibit significant antibacterial activity when assessed individually or in combination with antibiotics against clinical bacterial strains. CONCLUSIONS: Our findings reveal that M. albicans exhibits remarkable adjuvant potential for enhancing the effectiveness of antimicrobial drugs against resistant bacteria.


Asunto(s)
Acinetobacter baumannii , Antiinfecciosos , Melastomataceae , Plantas Medicinales , Staphylococcus aureus , Ciprofloxacina/farmacología , Plantas Medicinales/química , Espectrometría de Masas en Tándem , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Ampicilina/farmacología , Antiinfecciosos/farmacología , Bacterias
7.
J Neural Eng ; 20(5)2023 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-37879343

RESUMEN

Electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) are two commonly used non-invasive techniques for measuring brain activity in neuroscience and brain-computer interfaces (BCI).Objective. In this review, we focus on the use of EEG and fMRI in neurofeedback (NF) and discuss the challenges of combining the two modalities to improve understanding of brain activity and achieve more effective clinical outcomes. Advanced technologies have been developed to simultaneously record EEG and fMRI signals to provide a better understanding of the relationship between the two modalities. However, the complexity of brain processes and the heterogeneous nature of EEG and fMRI present challenges in extracting useful information from the combined data.Approach. We will survey existing EEG-fMRI combinations and recent studies that exploit EEG-fMRI in NF, highlighting the experimental and technical challenges.Main results. We made a classification of the different combination of EEG-fMRI for NF, we provide a review of multimodal analysis methods for EEG-fMRI features. We also survey the current state of research on EEG-fMRI in the different existing NF paradigms. Finally, we also identify some of the remaining challenges in this field.Significance. By exploring EEG-fMRI combinations in NF, we are advancing our knowledge of brain function and its applications in clinical settings. As such, this review serves as a valuable resource for researchers, clinicians, and engineers working in the field of neural engineering and rehabilitation, highlighting the promising future of EEG-fMRI-based NF.


Asunto(s)
Interfaces Cerebro-Computador , Neurorretroalimentación , Neurorretroalimentación/métodos , Imagen por Resonancia Magnética/métodos , Electroencefalografía/métodos , Encéfalo
8.
PLoS One ; 18(9): e0291528, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37756271

RESUMEN

Training motor imagery (MI) and motor observation (MO) tasks is being intensively exploited to promote brain plasticity in the context of post-stroke rehabilitation strategies. This may benefit from the use of closed-loop neurofeedback, embedded in brain-computer interfaces (BCI's) to provide an alternative non-muscular channel, which may be further augmented through embodied feedback delivered through virtual reality (VR). Here, we used functional magnetic resonance imaging (fMRI) in a group of healthy adults to map brain activation elicited by an ecologically-valid task based on a VR-BCI paradigm called NeuRow, whereby participants perform MI of rowing with the left or right arm (i.e., MI), while observing the corresponding movement of the virtual arm of an avatar (i.e., MO), on the same side, in a first-person perspective. We found that this MI-MO task elicited stronger brain activation when compared with a conventional MI-only task based on the Graz BCI paradigm, as well as to an overt motor execution task. It recruited large portions of the parietal and occipital cortices in addition to the somatomotor and premotor cortices, including the mirror neuron system (MNS), associated with action observation, as well as visual areas related with visual attention and motion processing. Overall, our findings suggest that the virtual representation of the arms in an ecologically-valid MI-MO task engage the brain beyond conventional MI tasks, which we propose could be explored for more effective neurorehabilitation protocols.


Asunto(s)
Interfaces Cerebro-Computador , Realidad Virtual , Adulto , Humanos , Imagen por Resonancia Magnética , Encéfalo/diagnóstico por imagen , Imágenes en Psicoterapia
9.
Neuroimage ; 280: 120353, 2023 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-37652114

RESUMEN

The simultaneous acquisition of electroencephalography and functional magnetic resonance imaging (EEG-fMRI) allows the complementary study of the brain's electrophysiology and hemodynamics with high temporal and spatial resolution. One application with great potential is neurofeedback training of targeted brain activity, based on the real-time analysis of the EEG and/or fMRI signals. This depends on the ability to reduce in real time the severe artifacts affecting the EEG signal acquired with fMRI, mainly the gradient and pulse artifacts. A few methods have been proposed for this purpose, but they are either slow, hardware-dependent, publicly unavailable, or proprietary software. Here, we present a fully open-source and publicly available tool for real-time EEG artifact reduction in simultaneous EEG-fMRI recordings that is fast and applicable to any hardware. Our tool is integrated in the Python toolbox NeuXus for real-time EEG processing and adapts to a real-time scenario well-established artifact average subtraction methods combined with a long short-term memory network for R peak detection. We benchmarked NeuXus on three different datasets, in terms of artifact power reduction and background signal preservation in resting state, alpha-band power reactivity to eyes closure, and event-related desynchronization during motor imagery. We showed that NeuXus performed at least as well as the only available real-time tool for conventional hardware setups (BrainVision's RecView) and a well-established offline tool (EEGLAB's FMRIB plugin). We also demonstrated NeuXus' real-time ability by reporting execution times under 250 ms. In conclusion, we present and validate the first fully open-source and hardware-independent solution for real-time artifact reduction in simultaneous EEG-fMRI studies.


Asunto(s)
Imagen por Resonancia Magnética , Neurorretroalimentación , Humanos , Artefactos , Electroencefalografía , Benchmarking
10.
Brain Res ; 1818: 148513, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37499729

RESUMEN

BACKGROUND: Previous functional magnetic resonance imaging studies have identified brain-connectivity alterations across multiple regions in people with migraine when compared to healthy controls. Few studies have focused on such changes throughout the different phases of the migraine cycle. We aimed to investigate functional connectivity during spontaneous occurring episodic migraine attacks, in comparison to interictal periods. METHODS: Eleven women with episodic migraine without aura underwent two sessions of resting-state fMRI, during and outside of a spontaneous migraine attack. Functional connectivity changes were assessed across canonical resting-state networks, identified by independent component analysis. Significantly altered connectivity was correlated with migraine attack symptoms. RESULTS: Decreased functional connectivity between subregions of the sensorimotor network (specifically, the primary somatosensory and motor cortices) and the posterior insula, bilaterally, was found during attacks. In both sessions, the functional connectivity between these regions was lower in patients who usually suffered longer attacks. DISCUSSION: The sensorimotor and insular regions are involved in nociceptive, autonomic, and somatosensory processing so the finding of reduced connectivity between these structures within a migraine attack is likely associated to the perception of pain and the heighten sensitivity to stimuli experienced in this disorder.


Asunto(s)
Epilepsia , Trastornos Migrañosos , Humanos , Femenino , Imagen por Resonancia Magnética/métodos , Trastornos Migrañosos/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Mapeo Encefálico/métodos
11.
Magn Reson Med ; 90(5): 1889-1904, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37382246

RESUMEN

PURPOSE: Arterial spin labeling (ASL) acquisitions at multiple post-labeling delays may provide more accurate quantification of cerebral blood flow (CBF), by fitting appropriate kinetic models and simultaneously estimating relevant parameters such as the arterial transit time (ATT) and arterial cerebral blood volume (aCBV). We evaluate the effects of denoising strategies on model fitting and parameter estimation when accounting for the dispersion of the label bolus through the vasculature in cerebrovascular disease. METHODS: We analyzed multi-delay ASL data from 17 cerebral small vessel disease patients (50 ± 9 y) and 13 healthy controls (52 ± 8 y), by fitting an extended kinetic model with or without bolus dispersion. We considered two denoising strategies: removal of structured noise sources by independent component analysis (ICA) of the control-label image timeseries; and averaging the repetitions of the control-label images prior to model fitting. RESULTS: Modeling bolus dispersion improved estimation precision and impacted parameter values, but these effects strongly depended on whether repetitions were averaged before model fitting. In general, repetition averaging improved model fitting but adversely affected parameter values, particularly CBF and aCBV near arterial locations in patients. This suggests that using all repetitions allows better noise estimation at the earlier delays. In contrast, ICA denoising improved model fitting and estimation precision while leaving parameter values unaffected. CONCLUSION: Our results support the use of ICA denoising to improve model fitting to multi-delay ASL and suggest that using all control-label repetitions improves the estimation of macrovascular signal contributions and hence perfusion quantification near arterial locations. This is important when modeling flow dispersion in cerebrovascular pathology.


Asunto(s)
Encéfalo , Imagen por Resonancia Magnética , Humanos , Imagen por Resonancia Magnética/métodos , Marcadores de Spin , Encéfalo/diagnóstico por imagen , Encéfalo/irrigación sanguínea , Arterias , Circulación Cerebrovascular/fisiología , Imagen de Perfusión/métodos
12.
Magn Reson Imaging ; 102: 141-150, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37343905

RESUMEN

PURPOSE: The consensus for the clinical implementation of arterial spin labeling (ASL) perfusion imaging recommends a segmented 3D Gradient and Spin-Echo (GRASE) readout for optimal signal-to-noise-ratio (SNR). The correction of the associated susceptibility-induced geometric distortions has been shown to improve diagnostic precision, but its impact on ASL data has not been systematically assessed and it is not consistently part of pre-processing pipelines. Here, we investigate the effects of susceptibility-induced distortion correction on perfusion imaging by pseudo-continuous ASL (pCASL) with a segmented 3D GRASE readout. METHODS: Data acquired from 28 women using pCASL with 3D GRASE at 3T was analyzed using three pre-processing options: without distortion correction, with distortion correction, and with spatial smoothing (without distortion correction) matched to control for blurring effects induced by distortion correction. Maps of temporal SNR (tSNR) and relative perfusion were analyzed in eight regions-of-interest (ROIs) across the brain. RESULTS: Distortion correction significantly affected tSNR and relative perfusion across the brain. Increases in tSNR were like those produced by matched spatial smoothing in most ROIs, indicating that they were likely due to blurring effects. However, that was not the case in the frontal and temporal lobes, where we also found increased relative perfusion with distortion correction even compared with matched spatial smoothing. These effects were found in both controls and patients, with no interactions with the participant group. CONCLUSION: Correction of susceptibility-induced distortions significantly impacts ASL perfusion imaging using a segmented 3D GRASE readout, and this step should therefore be considered in ASL pre-processing pipelines. This is of special importance in clinical studies, reporting perfusion across ROIs defined on relatively undistorted images and when conducting group analyses requiring the alignment of images across different subjects.


Asunto(s)
Encéfalo , Imagenología Tridimensional , Humanos , Femenino , Imagenología Tridimensional/métodos , Encéfalo/diagnóstico por imagen , Angiografía por Resonancia Magnética/métodos , Marcadores de Spin , Imagen de Perfusión , Circulación Cerebrovascular , Imagen por Resonancia Magnética/métodos
13.
Neuropsychologia ; 184: 108545, 2023 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-36934809

RESUMEN

Effective use of conceptual knowledge engages semantic representation and control processes to access information in a goal-driven manner. Neuropsychological findings of patients presenting either degraded knowledge (e.g., semantic dementia) or disrupted control (e.g., semantic aphasia) converge with neuroimaging evidence from young adults, and delineate the neural segregation of representation and control mechanisms. However, there is still scarce research on the neurofunctional underpinnings of such mechanisms in healthy ageing. To address this, we conducted an fMRI study, wherein young and older adults performed a covert naming task of typical and atypical objects. Three main age-related differences were found. As shown by age group and typicality interactions, older adults exhibited overactivation during naming of atypical (e.g., avocado) relative to typical concepts in brain regions associated to semantic representation, including anterior and medial portions of left temporal lobe (respectively, ATL and MTG). This provides evidence for the reorganization of neural activity in these brain regions contingent to the enrichment of semantic repositories in older ages. The medial orbitofrontal gyrus was also overactivated, indicating that the processing of atypical concepts (relative to typical items) taxes additional control resources in the elderly. Increased activation in the inferior frontal gyrus (IFG) was observed in naming typical items (relative to atypical ones), but only for young adults. This suggests that naming typical items (e.g., strawberry) taxes more on control processes in younger ages, presumably due to the semantic competition set by other items that share multiple features with the target (e.g., raspberry, blackberry, cherry). Together, these results reveal the dynamic nature of semantic control interplaying with conceptual representations as people grow older, by indicating that distinct neural bases uphold semantic performance from young to older ages. These findings may be explained by neural compensation mechanisms coming into play to support neurocognitive changes in healthy ageing.


Asunto(s)
Envejecimiento Saludable , Semántica , Adulto Joven , Humanos , Anciano , Mapeo Encefálico/métodos , Cognición/fisiología , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética
14.
Nutrients ; 15(6)2023 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-36986038

RESUMEN

The study of medicinal plants, such as the genus Garcinia (Clusiaceae), in the treatment of non-communicable chronic diseases has aroused the interest of researchers. However, there are no studies in the literature that have investigated the effects of Garcinia gardneriana in experimental models of obesity for possible metabolic alterations. Swiss mice receiving a high-fat diet were supplemented with aqueous or ethanolic extract of G. gardneriana at doses of 200 or 400 mg/kg/day. It was found that there was a reduction in food consumption in experimental groups compared with the control groups, and the group supplemented with aqueous extract at a dose of 200 mg/kg/daydisplayed a reduction in weight. The results showed an increase in the values of high density lipoprotein (HDL-c), total cholesterol, triglycerides and fasting blood glucose. G. gardneriana did not protect against insulin resistance, and caused in an increase in monocyte chemoattractant protein-1 (MCP-1) concentrations and a reduction in interleukin 10 (IL-10). In addition, hepatic steatosis and microvesicular steatosis were indicated. It was revealed that, under the experimental conditions in the study, G. gardneriana did not prevent weight gain or comorbidities; that is, a different behavior was obtained from that described in the literature with regard to the medicinal potential of the Garcinia species, which is probably related to the phytochemical properties.


Asunto(s)
Hígado Graso , Garcinia , Plantas Medicinales , Ratones , Animales , Garcinia/química , Extractos Vegetales/farmacología , Etanol , Agua , Dieta Alta en Grasa/efectos adversos
15.
Ann Vasc Surg ; 92: 201-210, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36690249

RESUMEN

BACKGROUND: To determine the importance of the hypogastric artery for the outcomes of survival, endoleaks, reinterventions, buttock claudication (BC), and perioperative mortality rate (PMR) in patients with aortoiliac aneurysms (AIA) receiving endovascular or open surgical (OS) repair. METHODS: This was a prospective consecutive cohort study of patients with AIA who underwent endovascular treatment or OS repair during the period of 2010-2021. Endovascular repair was performed with use of aortoiliac endoprosthesis associated with internal iliac artery (IIA) coil embolization and/or with iliac branch endoprosthesis (IBE) in order to preserve the IIA. The AIA OS repairs were performed with the artery ligation in order to exclude the IIA, or in some cases, the exclusion of the IIA was performed with an endosuture in the proximal stump of the artery. Three groups were identified in the postprocedural period: group 0 (no hypogastric arteries (HAs) preserved), group 1 (1 hypogastric artery preserved), and group 2 (2 hypogastric arteries preserved). RESULTS: A total of 91 patients were submitted to OS or endovascular surgery. Regarding the HA patency, there were 17 patients in group 0, 45 patients in group 1, and 29 patients in group 2. There were 17 cases of bowel ischemia (BI) (94.1% in group 0, 5.9% in group 1, and no cases in group 2, P < 0.001) most of them in group 0, with statistical significance, 12 cases of BC (91.7% in group 0, 8.3% in group 1, and no cases in group 2, P < 0.001), most of them in group 0, with statistical significance. The perioperative mortality was 14.3%, 13 patients (9 patients - 52.9% group 0, 3 patients - 6.7% group 1, and 1 patient - 3.4% group 2, P < 0.001). The linear regression analysis for survival rates showed that BI [P = 0.026 to hazard ratio (HR) = 1.69], emergency aortoiliac repair (P < 0.001, HR = 8.86), and number of HAs (P < 0.001, HR = 5.46) in postoperative were related to poorer survival rates in both univariate and multivariate analysis. The linear regression analysis showed that the number of HAs (P < 0.001, HR = 3.61) in postoperative, emergency aortoiliac repair (P = 0.002, HR 3.233), and cardiac disease (P = 0.048, HR = 3.84) were related to BI. CONCLUSIONS: In conclusion, the number of HA is crucial for adequate and safe outcomes after abdominal aortic aneurysm (AAA) repair. The main factors related to death were BI, emergency aortoiliac repair, and the number of HAs preserved. Moreover, the main factors related to BI were the number of HAs in postoperative, emergency aortoiliac repair, and cardiac disease.


Asunto(s)
Aneurisma de la Aorta Abdominal , Implantación de Prótesis Vascular , Procedimientos Endovasculares , Aneurisma Ilíaco , Humanos , Arteria Ilíaca/diagnóstico por imagen , Arteria Ilíaca/cirugía , Estudios Prospectivos , Estudios de Cohortes , Aneurisma Ilíaco/diagnóstico por imagen , Aneurisma Ilíaco/cirugía , Aneurisma Ilíaco/complicaciones , Implantación de Prótesis Vascular/efectos adversos , Resultado del Tratamiento , Procedimientos Endovasculares/efectos adversos , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/cirugía , Aneurisma de la Aorta Abdominal/complicaciones , Aorta Abdominal/cirugía , Arterias/cirugía , Estudios Retrospectivos
16.
Neuropsychology ; 37(2): 133-156, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36442005

RESUMEN

OBJECTIVE: Precursors of antisocial behavior in children may be associated with neuropsychological deficits, namely in executive functions (EF). The main objective of this systematic review and meta-analysis was to synthesize evidence of the relation between EF performance and early manifestations of antisocial behavior in children and adolescents. METHOD: The procedures of this systematic review and meta-analysis were based on the PRISMA recommendations. The review was based on a systematic search in the EBSCOhost and Pubmed databases. Fifty studies were included in this review, 37 of which contributed with data for meta-analysis. All studies examined the possible relation between the EF measures and behavior problems in childhood and adolescence. Meta-analytical procedures were performed, and the overall effect size was calculated from random-effect models, using the Comprehensive Meta-Analysis software. RESULTS: A substantial part of the studies report EF deficits in children and adolescents who present behavior problems, revealing that these deficits are already present in youth, long before being associated with antisocial behavior in adults, especially when in comorbidity with attention-deficit hyperactivity disorder (ADHD). Specifically, typical controls (TC) performed significantly better than disruptive behavior disorders (DBD) groups on measures of overall EF, g = -.35, 95% CI [-0.48, -0.22], p < .001. Similar results were found for working memory, g = -.26, 95% CI [-0.45, -0.07], p < .001, cognitive inhibition, g = -.30, 95% CI [-0.57, -0.04], p = .03, behavioral inhibition, g = -.45, 95% CI [-0.71, -0.19], p = .001, and cognitive flexibility (tests scores), g = -.31, 95% CI [-0.60, -0.02], p = .04. Comparing DBD + ADHD participants with TC, no significant differences were found, either for overall EF or for each dimension. Finally, DBD participants performed better than DBD + ADHD participants on measures of overall EF, g = .20, 95% CI [0.08, 0.33], p = .002. CONCLUSION: These findings are in line with neuropsychological theories arguing that executive dysfunctions may interfere with the children's and/or adolescents' ability to control their own conduct, in order to inhibit inappropriate behaviors in favor of the prosocial ones. This review and meta-analysis also identify the main characteristics and potential limitations of the existing studies. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad , Déficit de la Atención y Trastornos de Conducta Disruptiva , Niño , Adulto , Adolescente , Humanos , Déficit de la Atención y Trastornos de Conducta Disruptiva/complicaciones , Función Ejecutiva/fisiología , Trastorno por Déficit de Atención con Hiperactividad/psicología , Memoria a Corto Plazo/fisiología , Comorbilidad
17.
NMR Biomed ; 36(3): e4846, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36259628

RESUMEN

Magnetic resonance imaging (MRI) technology has profoundly transformed current healthcare systems globally, owing to advances in hardware and software research innovations. Despite these advances, MRI remains largely inaccessible to clinicians, patients, and researchers in low-resource areas, such as Africa. The rapidly growing burden of noncommunicable diseases in Africa underscores the importance of improving access to MRI equipment as well as training and research opportunities on the continent. The Consortium for Advancement of MRI Education and Research in Africa (CAMERA) is a network of African biomedical imaging experts and global partners, implementing novel strategies to advance MRI access and research in Africa. Upon its inception in 2019, CAMERA sets out to identify challenges to MRI usage and provide a framework for addressing MRI needs in the region. To this end, CAMERA conducted a needs assessment survey (NAS) and a series of symposia at international MRI society meetings over a 2-year period. The 68-question NAS was distributed to MRI users in Africa and was completed by 157 clinicians and scientists from across Sub-Saharan Africa (SSA). On average, the number of MRI scanners per million people remained at less than one, of which 39% were obsolete low-field systems but still in use to meet daily clinical needs. The feasibility of coupling stable energy supplies from various sources has contributed to the growing number of higher-field (1.5 T) MRI scanners in the region. However, these systems are underutilized, with only 8% of facilities reporting clinical scans of 15 or more patients per day, per scanner. The most frequently reported MRI scans were neurological and musculoskeletal. The CAMERA NAS combined with the World Health Organization and International Atomic Energy Agency data provides the most up-to-date data on MRI density in Africa and offers a unique insight into Africa's MRI needs. Reported gaps in training, maintenance, and research capacity indicate ongoing challenges in providing sustainable high-value MRI access in SSA. Findings from the NAS and focused discussions at international MRI society meetings provided the basis for the framework presented here for advancing MRI capacity in SSA. While these findings pertain to SSA, the framework provides a model for advancing imaging needs in other low-resource settings.


Asunto(s)
Imagen por Resonancia Magnética , Humanos , África del Sur del Sahara , Encuestas y Cuestionarios
18.
Cereb Cortex ; 33(7): 3816-3826, 2023 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-36030389

RESUMEN

Research on schizophrenia typically focuses on one paradigm for which clear-cut differences between patients and controls are established. Great efforts are made to understand the underlying genetical, neurophysiological, and cognitive mechanisms, which eventually may explain the clinical outcome. One tacit assumption of these "deep rooting" approaches is that paradigms tap into common and representative aspects of the disorder. Here, we analyzed the resting-state electroencephalogram (EEG) of 121 schizophrenia patients and 75 controls. Using multiple signal processing methods, we extracted 194 EEG features. Sixty-nine out of the 194 EEG features showed a significant difference between patients and controls, indicating that these features detect an important aspect of schizophrenia. Surprisingly, the correlations between these features were very low. We discuss several explanations to our results and propose that complementing "deep" with "shallow" rooting approaches might help in understanding the underlying mechanisms of the disorder.


Asunto(s)
Esquizofrenia , Humanos , Esquizofrenia/genética , Electroencefalografía , Procesamiento de Señales Asistido por Computador
19.
Front Neurogenom ; 4: 1080794, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38234500

RESUMEN

Introduction: Motor Imagery (MI)-based Brain Computer Interfaces (BCI) have raised gained attention for their use in rehabilitation therapies since they allow controlling an external device by using brain activity, in this way promoting brain plasticity mechanisms that could lead to motor recovery. Specifically, rehabilitation robotics can provide precision and consistency for movement exercises, while embodied robotics could provide sensory feedback that can help patients improve their motor skills and coordination. However, it is still not clear whether different types of visual feedback may affect the elicited brain response and hence the effectiveness of MI-BCI for rehabilitation. Methods: In this paper, we compare two visual feedback strategies based on controlling the movement of robotic arms through a MI-BCI system: 1) first-person perspective, with visual information that the user receives when they view the robot arms from their own perspective; and 2) third-person perspective, whereby the subjects observe the robot from an external perspective. We studied 10 healthy subjects over three consecutive sessions. The electroencephalographic (EEG) signals were recorded and evaluated in terms of the power of the sensorimotor rhythms, as well as their lateralization, and spatial distribution. Results: Our results show that both feedback perspectives can elicit motor-related brain responses, but without any significant differences between them. Moreover, the evoked responses remained consistent across all sessions, showing no significant differences between the first and the last session. Discussion: Overall, these results suggest that the type of perspective may not influence the brain responses during a MI- BCI task based on a robotic feedback, although, due to the limited sample size, more evidence is required. Finally, this study resulted into the production of 180 labeled MI EEG datasets, publicly available for research purposes.

20.
Int J Nanomedicine ; 17: 4321-4337, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36147546

RESUMEN

Purpose: Silver nanoparticles (AgNPs) have shown great potential as anticancer agents, namely in therapies' resistant forms of cancer. The progression of prostate cancer (PCa) to resistant forms of the disease (castration-resistant PCa, CRPC) is associated with poor prognosis and life quality, with current limited therapeutic options. CRPC is characterized by a high glucose consumption, which poses as an opportunity to direct AgNPs to these cancer cells. Thus, this study explores the effect of glucose functionalization of AgNPs in PCa and CRPC cell lines (LNCaP, Du-145 and PC-3). Methods: AgNPs were synthesized, further functionalized, and their physical and chemical composition was characterized both in water and in culture medium, through UV-visible spectrum, dynamic light scattering (DLS), transmission electron microscopy (TEM) and Fourier-transform infrared spectroscopy (FTIR). Their effect was assessed in the cell lines regarding AgNPs' entering pathway, cellular proliferation capacity, ROS production, mitochondrial membrane depolarization, cell cycle analysis and apoptosis evaluation. Results: AgNPs displayed an average size of 61nm and moderate monodispersity with a slight increase after functionalization, and a round shape. These characteristics remained stable when redispersed in culture medium. Both AgNPs and G-AgNPs were cytotoxic only to CRPC cells and not to hormone-sensitive ones and their effect was higher after functionalization showing the potential of glucose to favor AgNPs' uptake by cancer cells. Entering through endocytosis and being encapsulated in lysosomes, the NPs increased the ROS, inducing mitochondrial damage, and arresting cell cycle in S Phase, therefore blocking proliferation, and inducing apoptosis. Conclusion: The nanoparticles synthesized in the present study revealed good characteristics and stability for administration to cancer cells. Their uptake through endocytosis leads to promising cytotoxic effects towards CRPC cells, revealing the potential of G-AgNPs as a future therapeutic approach to improve the management of patients with PCa resistant to hormone therapy or metastatic disease.


Asunto(s)
Antineoplásicos , Nanopartículas del Metal , Neoplasias de la Próstata Resistentes a la Castración , Antineoplásicos/química , Antineoplásicos/farmacología , Glucosa , Hormonas , Humanos , Masculino , Nanopartículas del Metal/química , Extractos Vegetales/química , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Especies Reactivas de Oxígeno , Plata/química , Plata/farmacología , Agua
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...