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BACKGROUND: The neurobiological underpinnings of Autism Spectrum Disorder (ASD) are diverse and likely multifactorial. One possible mechanism is increased oxidative stress leading to altered neurodevelopment and brain function. However, this hypothesis has mostly been tested in post-mortem studies. So far, available in vivo studies in autistic individuals have reported no differences in glutathione (GSH) levels in frontal, occipital, and subcortical regions. However, these studies were limited by the technically challenging quantification of GSH, the main brain antioxidant molecule. This study aimed to overcome previous studies' limitations by using a GSH-tailored spectroscopy sequence and optimised quantification methodology to provide clarity on GSH levels in autistic adults. METHODS: We used spectral editing proton-magnetic resonance spectroscopy (1H-MRS) combined with linear combination model fitting to quantify GSH in the dorsomedial prefrontal cortex (DMPFC) and medial occipital cortex (mOCC) of autistic and non-autistic adults (male and female). We compared GSH levels between groups. We also examined correlations between GSH and current autism symptoms, measured using the Autism Quotient (AQ). RESULTS: Data were available from 31 adult autistic participants (24 males, 7 females) and 40 non-autistic participants (21 males, 16 females); the largest sample to date. The GSH levels did not differ between groups in either region. No correlations with AQ were observed. CONCLUSION: GSH levels as measured using 1H-MRS are unaltered in the DMPFC and mOCC regions of autistic adults, suggesting that oxidative stress in these cortical regions is not a marked neurobiological signature of ASD.
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Transtorno do Espectro Autista , Transtorno Autístico , Glutationa , Lobo Occipital , Humanos , Masculino , Feminino , Glutationa/metabolismo , Glutationa/análise , Adulto , Lobo Occipital/metabolismo , Lobo Occipital/diagnóstico por imagem , Transtorno do Espectro Autista/metabolismo , Transtorno Autístico/metabolismo , Adulto Jovem , Espectroscopia de Prótons por Ressonância Magnética , Lobo Frontal/metabolismo , Estresse Oxidativo , Pessoa de Meia-Idade , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/diagnóstico por imagemRESUMO
White crowberries (Corema album) are a fruit from an endemic shrub found in Southern European Atlantic costal dunes. Although this shrub and its fruits never became a formal commercial crop for a number of reasons, it has a long-lasting relevance and tradition, much associated with summer, beach and holidays. The main goal of this study was to conduct a thematic analysis of the words and small expressions people associate with white crowberries. For that, a questionnaire was used, and the participants were asked to indicate in an open-ended question which top-of-mind words/small expressions they associate with white crowberries. A total of 501 people participated in this study, of which only 394 knew about white crowberries, and from those, only 229 answered the open-ended question of interest to this purpose. The results showed that the words/small expressions given by the participants were distributed between five categories (1-Memories of places, people and times, 2-Emotions and experiences, 3-Sensorial perception, 4-Properties and uses, and 5-Natural resources' valuation). Additionally, 18 subcategories were also identified. The most representative of the categories was sensorial perception and the most relevant of the subcategories was habitats (a subcategory from category 1). The most frequent words mentioned by the participants were beach, berry and summer. In addition, the effect of sociodemographic groups was investigated and some variations were observed in the categories of the words mentioned by the participants according to sex, living environment or region. This work allowed for the identification of a high variability in the words or expressions that account for a rich patrimony of tacit knowledge, memories, emotions and perceptions of the population towards white crowberries, thus confirming their social as well as nutritional relevance.
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In neurons, it is commonly assumed that mitochondrial replication only occurs in the cell body, after which the mitochondria must travel to the neuron's periphery. However, while mitochondrial DNA replication has been observed to occur away from the cell body, the specific mechanisms involved remain elusive. Using EdU-labelling in mouse primary neurons, we developed a tool to determine the mitochondrial replication rate. Taking of advantage of microfluidic devices, we confirmed that mitochondrial replication also occurs locally in the periphery of neurons. To achieve this, mitochondria require de novo nuclear-encoded, but not mitochondrial-encoded protein translation. Following a proteomic screen comparing synaptic with non-synaptic mitochondria, we identified two elongation factors - eEF1A1 and TUFM - that were upregulated in synaptic mitochondria. We found that mitochondrial replication is impaired upon the downregulation of eEF1A1, and this is particularly relevant in the periphery of neurons.
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Alterations in γ-aminobutyric acid (GABA) have been implicated in sensory differences in individuals with autism spectrum disorder (ASD). Visual signals are initially processed in the retina, and in this study, we explored the hypotheses that the GABA-dependent retinal response to light is altered in individuals with ASD. Light-adapted electroretinograms were recorded from 61 adults (38 males and 23 females; n = 22 ASD) in response to three stimulus protocols: (1) the standard white flash, (2) the standard 30â Hz flickering protocol, and (3) the photopic negative response protocol. Participants were administered an oral dose of placebo, 15 or 30â mg of arbaclofen (STX209, GABAB agonist) in a randomized, double-blind, crossover order before the test. At baseline (placebo), the a-wave amplitudes in response to single white flashes were more prominent in ASD, relative to typically developed (TD) participants. Arbaclofen was associated with a decrease in the a-wave amplitude in ASD, but an increase in TD, eliminating the group difference observed at baseline. The extent of this arbaclofen-elicited shift significantly correlated with the arbaclofen-elicited shift in cortical responses to auditory stimuli as measured by using an electroencephalogram in our prior study and with broader autistic traits measured with the autism quotient across the whole cohort. Hence, GABA-dependent differences in retinal light processing in ASD appear to be an accessible component of a wider autistic difference in the central processing of sensory information, which may be upstream of more complex autistic phenotypes.
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Transtorno do Espectro Autista , Masculino , Adulto , Feminino , Humanos , Transtorno do Espectro Autista/tratamento farmacológico , Retina , Eletroencefalografia , Ácido gama-Aminobutírico , EletrorretinografiaRESUMO
Men with antisocial personality disorder (ASPD) with or without psychopathy (+/-P) are responsible for most violent crime in society. Development of effective treatments is hindered by poor understanding of the neurochemical underpinnings of the condition. Men with ASPD with and without psychopathy demonstrate impulsive decision-making, associated with striatal abnormalities in functional neuroimaging studies. However, to date, no study has directly examined the potential neurochemical underpinnings of such abnormalities. We therefore investigated striatal glutamate: GABA ratio using Magnetic Resonance Spectroscopy in 30 violent offenders (16 ASPD-P, 14 ASPD + P) and 21 healthy non-offenders. Men with ASPD +/- P had a significant reduction in striatal glutamate : GABA ratio compared to non-offenders. We report, for the first time, striatal Glutamate/GABA dysregulation in ASPD +/- P, and discuss how this may be related to core behavioral abnormalities in the disorders.
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Transtorno da Personalidade Antissocial , Corpo Estriado , Criminosos , Ácido Glutâmico , Violência , Ácido gama-Aminobutírico , Humanos , Masculino , Ácido Glutâmico/metabolismo , Transtorno da Personalidade Antissocial/metabolismo , Ácido gama-Aminobutírico/metabolismo , Adulto , Criminosos/psicologia , Corpo Estriado/metabolismo , Violência/psicologia , Espectroscopia de Ressonância Magnética/métodos , Pessoa de Meia-Idade , Adulto JovemRESUMO
The success of screening programs depends to a large extent on the adherence of the target population, so it is therefore of fundamental importance to develop computer simulation models that make it possible to understand the factors that correlate with this adherence, as well as to identify population groups with low adherence to define public health strategies that promote behavioral change. Our aim is to demonstrate that it is possible to simulate screening adherence behavior using computer simulations. Three versions of an agent-based model are presented using different methods to determine the agent's individual decision to adhere to screening: (a) logistic regression; (b) fuzzy logic components and (c) a combination of the previous. All versions were based on real data from 271,867 calls for diabetic retinopathy screening. The results obtained are statistically very close to the real ones, which allows us to conclude that despite having a high degree of abstraction from the real data, the simulations are very valid and useful as a tool to support decisions in health planning, while evaluating multiple scenarios and accounting for emergent behavior.
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Diabetes Mellitus , Retinopatia Diabética , Humanos , Simulação por Computador , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/epidemiologia , Programas de Rastreamento/métodos , Lógica Fuzzy , Modelos LogísticosRESUMO
Autism spectrum disorder (ASD) is a neurodevelopmental condition which compromises various cognitive and behavioural domains. The understanding of the pathophysiology and molecular neurobiology of ASD is still an open critical research question. Here, we aimed to address ASD neurochemistry in the same time point at key regions that have been associated with its pathophysiology: the insula, hippocampus, putamen and thalamus. We conducted a multivoxel proton magnetic resonance spectroscopy (1H-MRS) study to non-invasively estimate the concentrations of total choline (GPC + PCh, tCho), total N-acetyl-aspartate (NAA + NAAG, tNAA) and Glx (Glu + Gln), presenting the results as ratios to total creatine while investigating replication for ratios to total choline as a secondary analysis. Twenty-two male children aged between 10 and 18 years diagnosed with ASD (none with intellectual disability, in spite of the expected lower IQ) and 22 age- and gender-matched typically developing (TD) controls were included. Aspartate ratios were significantly lower in the insula (tNAA/tCr: p = 0.010; tNAA/tCho: p = 0.012) and putamen (tNAA/tCr: p = 0.015) of ASD individuals in comparison with TD controls. The Glx ratios were significantly higher in the hippocampus of the ASD group (Glx/tCr: p = 0.027; Glx/tCho: p = 0.011). Differences in tNAA and Glx indices suggest that these metabolites might be neurochemical markers of region-specific atypical metabolism in ASD children, with a potential contribution for future advances in clinical monitoring and treatment.
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Transtorno do Espectro Autista , Transtorno Autístico , Criança , Humanos , Masculino , Adolescente , Transtorno Autístico/metabolismo , Glutamina/metabolismo , Transtorno do Espectro Autista/diagnóstico por imagem , Transtorno do Espectro Autista/metabolismo , Ácido Aspártico/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Colina/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Creatina/metabolismo , Ácido Glutâmico/metabolismoRESUMO
Animal songs can change within and between populations as the result of different evolutionary processes. When these processes include cultural transmission, the social learning of information or behaviours from conspecifics, songs can undergo rapid evolutions because cultural novelties can emerge more frequently than genetic mutations. Understanding these song variations over large temporal and spatial scales can provide insights into the patterns, drivers and limits of song evolution that can ultimately inform on the species' capacity to adapt to rapidly changing acoustic environments. Here, we analysed changes in fin whale (Balaenoptera physalus) songs recorded over two decades across the central and eastern North Atlantic Ocean. We document a rapid replacement of song INIs (inter-note intervals) over just four singing seasons, that co-occurred with hybrid songs (with both INIs), and a clear geographic gradient in the occurrence of different song INIs during the transition period. We also found gradual changes in INIs and note frequencies over more than a decade with fin whales adopting song changes. These results provide evidence of vocal learning in fin whales and reveal patterns of song evolution that raise questions on the limits of song variation in this species.
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Baleia Comum , Animais , Acústica , Oceano Atlântico , Mutação , Estações do AnoRESUMO
Developing biocompatible, non-fouling and biodegradable hydrogels for blood-contacting devices remains a demanding challenge. Such materials should promote natural healing, prevent clotting, and undergo controlled degradation. This study evaluates the biocompatibility and biodegradation of degradable poly(2-hydroxyethyl methacrylate) (d-pHEMA) hydrogels with or without reinforcement with oxidized few-layer graphene (d-pHEMA/M5ox) in a long term implantation in rats, assessing non-desired side-effects (irritation, chronic toxicity, immune response). Subcutaneous implantation over 6 months revealed degradation of both hydrogels, despite slower for d-pHEMA/M5ox, with degradation products found in intracellular vesicles. No inflammation nor infection at implantation areas were observed, and no histopathological findings were detected in parenchymal organs. Immunohistochemistry confirmed d-pHEMA and d-pHEMA/M5ox highly anti-adhesiveness. Gene expression of macrophages markers revealed presence of both M1 and M2 macrophages at all timepoints. M1/M2 profile after 6 months reveals an anti-inflammatory environment, suggesting no chronic inflammation, as also demonstrated by cytokines (IL-α, TNF-α and IL-10) analysis. Overall, modification of pHEMA towards a degradable material was successfully achieved without evoking a loss of its inherent properties, specially its anti-adhesiveness and biocompatibility. Therefore, these hydrogels hold potential as blank-slate for further modifications that promote cellular adhesion/proliferation for tissue engineering applications, namely for designing blood contacting devices with different load bearing requirements. STATEMENT OF SIGNIFICANCE: Biocompatibility, tunable biodegradation kinetics, and suitable immune response with lack of chronic toxicity and irritation, are key features in degradable blood contact devices that demand long-term exposure. We herein evaluate the 6-month in vivo performance of a degradable and hemocompatible anti-adhesive hydrogel based in pHEMA, and its mechanically reinforced formulation with few-layer graphene oxide. This subcutaneous implantation in a rat model, shows gradual degradation with progressive changes in material morphology, and no evidence of local inflammation in surrounding tissue, neither signs of inflammation or adverse reactions in systemic organs, suggesting biocompatibility of degradation products. Such hydrogels exhibit great potential as a blank slate for tissue engineering applications, including for blood contact, where cues for specific cells can be incorporated.
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Grafite , Ratos , Animais , Grafite/farmacologia , Poli-Hidroxietil Metacrilato/química , Hidrogéis/farmacologia , Hidrogéis/química , Engenharia Tecidual , Inflamação , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/químicaRESUMO
INTRODUCTION: Neurocutaneous syndromes (NCS) are a heterogeneous group of conditions with multiorgan involvement and diverse manifestations, evolving throughout life with significant morbidity. A multidisciplinary approach to NCS patients has been advocated, although a specific model is not yet established. The aim of this study was 1) to describe the organization of the recently created Multidisciplinary Outpatient Clinic of Neurocutaneous Diseases (MOCND) at a Portuguese pediatric tertiary hospital; 2) to share our institutional experience focusing on the most common conditions, neurofibromatosis type 1 (NF1) and tuberous sclerosis complex (TSC); 3) to analyze the advantages of a multidisciplinary center and approach in NCS. METHODS: Retrospective analysis of 281 patients enrolled in the MOCND over the first five years of activity (October 2016 to December 2021), reviewing genetics, family history, clinical features, complications, and therapeutic strategies for NF1 and TSC. RESULTS: The clinic works weekly with a core team of pediatricians and pediatric neurologists supported by other specialties as needed. Of the 281 patients enrolled, 224 (79.7%) had identifiable syndromes such as NF1 (n = 105), TSC (n = 35), hypomelanosis of Ito (n = 11), Sturge-Weber syndrome (n = 5), and others. In NF1 patients, 41.0% had a positive family history, all manifested café-au-lait macules, 38.1% neurofibromas with 45.0% being large plexiform neurofibromas. Sixteen were under treatment with selumetinib. Genetic testing was performed in 82.9% of TSC patients with pathogenic variants found in TSC2 gene in 72.4% patients (82.7% if considered contiguous gene syndrome). Family history was positive in 31.4%. All TSC patients presented hypomelanotic macules and fulfilled diagnostic criteria. Fourteen patients were being treated with mTOR inhibitors. CONCLUSION: Offering a systematic and multidisciplinary approach to NCS patients enables timely diagnosis, promotes a structured follow-up, and encourages discussion to outline management plans for optimal care to every patient, with significant impact on the quality of life of patients and families.
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Síndromes Neurocutâneas , Neurofibromatose 1 , Humanos , Criança , Portugal , Síndromes Neurocutâneas/diagnóstico , Síndromes Neurocutâneas/terapia , Qualidade de Vida , Estudos Retrospectivos , Centros de Atenção Terciária , Instituições de Assistência Ambulatorial , Neurofibromatose 1/terapiaRESUMO
Impact of climate change is expected to be especially noticeable at the edges of a species' distribution, where they meet suboptimal habitat conditions. In Mauritania and Iberia, two genetically differentiated populations of harbor porpoises (Phocoena phocoena) form an ecotype adapted to local upwelling conditions and distinct from other ecotypes further north on the NE Atlantic continental shelf and in the Black Sea. By analyzing the evolution of mitochondrial genetic variation in the Iberian population between two temporal cohorts (1990-2002 vs. 2012-2015), we report a substantial decrease in genetic diversity. Phylogenetic analyses including neighboring populations identified two porpoises in southern Iberia carrying a divergent haplotype closely related to those from the Mauritanian population, yet forming a distinct lineage. This suggests that Iberian porpoises may not be as isolated as previously thought, indicating possible dispersion from Mauritania or an unknown population in between, but none from the northern ecotype. Demo-genetic scenario testing by approximate Bayesian computation showed that the rapid decline in the Iberian mitochondrial diversity was not simply due to the genetic drift of a small population, but models support instead a substantial decline in effective population size, possibly resulting from environmental stochasticity, prey depletion, or acute fishery bycatches. These results illustrate the value of genetics time series to inform demographic trends and emphasize the urgent need for conservation measures to ensure the viability of this small harbor porpoise population in Iberian waters.
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INTRODUCTION: Dihydropteridine reductase deficiency (DHPRD) is a rare genetic disorder of tetrahydrobiopterin (BH4) regeneration, a cofactor for several enzymes, including phenylalanine hydroxylase. Due to hyperphenylalaninemia (HPA), patients can be detected by the newborn metabolic screening, when available. The most common symptoms of DHPRD may mimic cerebral palsy: developmental/cognitive impairment, hypotonia, peripheral hypertonia, dystonia, feeding difficulties, epilepsy, and microcephaly. The long-term neurodevelopmental outcome is strongly influenced by the early initiation of effective treatment. CASE REPORT: A 2-year-old boy, born in Guinea, was evaluated in our center with the diagnosis of "cerebral palsy". He was born after a prolonged labor, and had feeding difficulties and severe developmental delay. Examination revealed microcephaly, axial hypotonia, and dyskinetic movements without hypertension. No seizures or oculogyric crisis were reported. Brain MRI showed slight brain atrophy and hyperintensity T2/FLAIR in basal ganglia. The diagnosis of cerebral palsy was questioned, and further investigation was carried out. HPA raised the possibility of BH4 deficiency, supported by increased biopterin in urine, decreased neurotransmitters in CSF, and low DHPR enzyme activity. A variant (128_130del (p.(Val43del)) in apparent homozygosity was later detected in the QPDR gene. At 4 years old, he started L-dopa/carbidopa, oxitriptan, and a phenylalanine-restrictive diet with moderate clinical improvement. CONCLUSION: When the diagnosis of "cerebral palsy" is questionable, other etiologies should be investigated, particularly disorders that have specific disease-modifying treatment. In our patient, the atypical constellation of neurological signs, brain MRI findings, and the nonexistence of newborn metabolic screening in the country of origin supported additional investigation. The presence of HPA-associated dystonia was crucial to the investigation and was later confirmed as DHPRD. Unfortunately, at this stage, the reversibility of the neurological damage in response to treatment is doubtful.
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Altered reactivity and responses to auditory input are core to the diagnosis of autism spectrum disorder (ASD). Preclinical models implicate Ï-aminobutyric acid (GABA) in this process. However, the link between GABA and auditory processing in humans (with or without ASD) is largely correlational. As part of a study of potential biosignatures of GABA function in ASD to inform future clinical trials, we evaluated the role of GABA in auditory repetition suppression in 66 adults (n = 28 with ASD). Neurophysiological responses (temporal and frequency domains) to repetitive standard tones and novel deviants presented in an oddball paradigm were compared after double-blind, randomized administration of placebo, 15 or 30 mg of arbaclofen (STX209), a GABA type B (GABAB) receptor agonist. We first established that temporal mismatch negativity was comparable between participants with ASD and those with typical development (TD). Next, we showed that temporal and spectral responses to repetitive standards were suppressed relative to responses to deviants in the two groups, but suppression was significantly weaker in individuals with ASD at baseline. Arbaclofen reversed weaker suppression of spectral responses in ASD but disrupted suppression in TD. A post hoc analysis showed that arbaclofen-elicited shift in suppression was correlated with autistic symptomatology measured using the Autism Quotient across the entire group, though not in the smaller sample of the ASD and TD group when examined separately. Thus, our results confirm: GABAergic dysfunction contributes to the neurophysiology of auditory sensory processing alterations in ASD, and can be modulated by targeting GABAB activity. These GABA-dependent sensory differences may be upstream of more complex autistic phenotypes.
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Transtorno do Espectro Autista , Transtorno Autístico , Adulto , Humanos , Percepção Auditiva/fisiologia , Agonistas dos Receptores de GABA-B/farmacologia , Agonistas dos Receptores de GABA-B/uso terapêutico , Ácido gama-AminobutíricoRESUMO
This study characterises microplastics in small cetaceans on the coast of Portugal and assesses the relationship between several biological variables and the amount of detected microplastics. The intestines of 38 stranded dead cetaceans were processed in the laboratory, with digestion methods adapted to the amount of organic matter in each sample. The influence of several biological and health variables (e.g., species, sex, body condition) on the amount of microplastics was tested in all analysed species and particularly in common dolphins, due to the larger number of available samples. Most of the analysed individuals had microplastics in the intestine (92.11%), with harbour porpoises revealing a significantly higher median number of microplastics than common dolphins, probably due to their different diets, use of habitat and feeding strategies. None of the other tested variables significantly influenced the number of microplastics. Moreover, the microplastics found should not be enough to cause physical or chemical sublethal effects, although the correlation between microplastic ingestion and plastic additive bioaccumulation in cetacean tissues requires further investigation. Future monitoring in biota should rely on improved and standardised protocols for microplastic analyses in complex samples to allow for accurate analyses of larger samples and spatio-temporal comparisons.
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Infection by Toxoplasma gondii may compromise the intestinal histoarchitecture through the tissue reaction triggered by the parasite. Thus, this study evaluated whether treatment with rosuvastatin modifies duodenal changes caused by the chronic infection induced by cysts of T. gondii. For this, female Swiss mice were distributed into infected and treated group (ITG), infected group (IG), group treated with 40 mg/kg rosuvastatin (TG) and control group (CG). After 72 days of infection, the animals were euthanized, the duodenum was collected and processed for histopathological analysis. We observed an increase in immune cell infiltration in the IG, TG and ITG groups, with injury to the Brunner glands. The infection led to a reduction in collagen fibers and mast cells. Infected and treated animals showed an increase in collagen fibers, acidic mucin-producing goblet cells, intraepithelial lymphocytes and mast cells, in addition to the reduction of muscle, neutral mucin-producing and Paneth cells. While treatment with rosuvastatin alone led to increased muscle layer, proportion of neutral mucin-producing goblet cells, Paneth cells, and reduction of collagen fibers. These findings indicate that the infection and treatment caused changes in the homeostasis of the intestinal wall and treatment with rosuvastatin potentiated most parameters indicative of inflammation.
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Toxoplasma , Feminino , Animais , Camundongos , Rosuvastatina Cálcica/farmacologia , Rosuvastatina Cálcica/uso terapêutico , Duodeno , Mucinas , ColágenoRESUMO
The Iberian harbour porpoise population is small and fisheries bycatch has been described as one of its most important threats. Data on harbour porpoise strandings collected by the Portuguese and Galician stranding networks between 2000 and 2020 are indicative of a recent mortality increase in the western Iberian coast (particularly in northern Portugal). Overall, in Portugal and Galicia, individuals stranded due to confirmed fishery interaction represented 46.98% of all analysed porpoises, and individuals stranded due to probable fishery interaction represented another 10.99% of all analysed porpoises. Considering the Portuguese annual abundance estimates available between 2011 and 2015, it was possible to calculate that an annual average of 207 individuals was removed from the population in Portuguese waters alone, which largely surpasses the potential biological removal (PBR) estimates (22 porpoises, CI: 12-43) for the same period. These results are conservative and bycatch values from strandings are likely underestimated. A structured action plan accounting for new activities at sea is needed to limit the Iberian porpoise population decline. Meanwhile, there is an urgent need for a fishing effort reorganization to directly decrease porpoise mortality.
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Triboelectric nanogenerators (TENGs) are associated with several drawbacks that limit their application in the biomedical field, including toxicity, thrombogenicity, and poor performance in the presence of fluids. By proposing the use of a hemo/biocompatible hydrogel, poly(2-hydroxyethyl methacrylate) (pHEMA), this study bypasses these barriers. In contact-separation mode, using polytetrafluoroethylene (PTFE) as a reference, pHEMA generates an output of 100.0 V, under an open circuit, 4.7 µA, and 0.68 W/m2 for an internal resistance of 10 MΩ. Our findings unveil that graphene oxide (GO) can be used to tune pHEMA's triboelectric properties in a concentration-dependent manner. At the lowest measured concentration (0.2% GO), the generated outputs increase to 194.5 V, 5.3 µA, and 1.28 W/m2 due to the observed increase in pHEMA's surface roughness, which expands the contact area. Triboelectric performance starts to decrease as GO concentration increases, plateauing at 11% volumetric, where the output is 51 V, 1.76 µA, and 0.17 W/m2 less than pHEMA's. Increases in internal resistance, from 14 ΩM to greater than 470 ΩM, ζ-potential, from -7.3 to -0.4 mV, and open-circuit characteristic charge decay periods, from 90 to 120 ms, are all observed in conjunction with this phenomenon, which points to GO function as an electron trapping site in pHEMA's matrix. All of the composites can charge a 10 µF capacitor in 200 s, producing a voltage between 0.25 and 3.5 V and allowing the operation of at least 20 LEDs. The triboelectric output was largely steady throughout the 3.33 h durability test. Voltage decreases by 38% due to contact-separation frequency, whereas current increases by 77%. In terms of pressure, it appears to have little effect on voltage but boosts current output by 42%. Finally, pHEMA and pHEMA/GO extracts were cytocompatible toward fibroblasts. According to these results, pHEMA has a significant potential to function as a biomaterial to create bio/hemocompatible TENGs and GO to precisely control its triboelectric outputs.
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Eletrônica Médica , Hidrogéis , Elétrons , Poli-Hidroxietil MetacrilatoRESUMO
BACKGROUND: Computerized cognitive training programs may have benefited the self-assessment of memory, quality of life, and mood among older adults during the coronavirus disease 2019 (COVID-19) pandemic. OBJECTIVE: To determine the subjective impacts of computerized cognitive training on mood, frequency of forgetfulness, memory complaints, and quality of life in the elderly using an online platform. METHODS: In total, 66 elderly participants of USP 60 + , a program for the elderly offered by Universidade de São Paulo, who voluntarily enrolled in the study were selected and randomized with an allocation ratio of 1:1 into 2 groups: the training group (n = 33) and the control group (n = 33). After signing the free and informed consent form, they answered a protocol which included a sociodemographic questionnaire, the Memory Complaints Questionnaire (MAC-Q), the McNair and Kahn's Frequency of Forgetfulness Scale, the Geriatric Depression Scale (GDS-15), the Geriatric Anxiety Inventory (GAI), and the Control, Autonomy, Self-Realization, and Pleasure (CASP-19) questionnaire. The training cognitive game platform aimed to stimulate various cognitive aspects, including memory, attention, language, executive functions (reasoning, logical thinking), and visual and spatial skills. RESULTS: The participants of the training group showed a reduction in the MAC-Q, MacNair and Kahn, and GAI scores in the pre- and posttest comparison. Significant differences were identified between the groups regarding the total scores of the MAC-Q in the post-test, which was also evidenced by the logistic regression. CONCLUSION: Participation in a computerized cognitive intervention promoted reductions in memory complaints, frequency of forgetfulness, and anxiety symptoms, in addition to improving self-reported quality of life.
ANTECEDENTES: Programas informatizados de treinamento cognitivo podem ter beneficiado a autoavaliação da memória, a qualidade de vida e o humor entre os idosos durante a pandemia de doença do coronavírus 2019 (coronavirus disease 2019, COVID-19, em inglês). OBJETIVO: Determinar os impactos subjetivos do treinamento cognitivo computadorizado no humor, na frequência de esquecimento, nas queixas de memória, e na qualidade de vida em idosos utilizando uma plataforma online. MéTODOS: Ao todo, 66 idosos participantes do programa USP 60 + , oferecido à terceira idade pela Universidade de São Paulo, e inscritos voluntariamente no estudo, foram selecionados e randomizados em uma razão de 1:1 em 2 grupos: grupo treinamento (n = 33) e grupo controle (n = 33). Após assinarem o termo de consentimento livre e esclarecido, os participantes responderam a um protocolo que incluía um questionário sociodemográfico, o Questionário de Queixas de Memória (Memory Complaints Questionnaire, MAC-Q), A Escala de Frequência de Esquecimento de McNair e Kahn, a Escala de Depressão Geriátrica (Geriatric Depression Scale, GDS-15), o Inventário de Ansiedade Geriátrica (Geriatric Anxiety Inventory, GAI), e o questionário de Controle, Autonomia, Autorrealização e Prazer (Control, Autonomy, Self-Realization, and Pleasure, CASP-19). A plataforma de jogos cognitivos de treinamento visou estimular diversos aspectos cognitivos, incluindo memória, atenção, linguagem, funções executivas (raciocínio, raciocínio lógico) e habilidades visuais e espaciais. RESULTADOS: Na comparação pré e pós-teste, os participantes do grupo de treinamento apresentaram redução nas pontuações do MAC-Q, da escala McNair e Kahn e do GAI. Diferenças significativas entre os grupos quanto às pontuações totais da escala MAC-Q no pós-teste também foram evidenciadas pela regressão logística. CONCLUSãO: A participação em uma intervenção cognitiva computadorizada promoveu reduções nas queixas de memória, frequência de esquecimento e sintomas de ansiedade, além de melhorar a qualidade de vida autorrelatada.
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COVID-19 , Pandemias , Humanos , Idoso , Qualidade de Vida , Treino Cognitivo , Brasil/epidemiologia , Transtornos da Memória , CogniçãoRESUMO
Degradable biomaterials for blood-contacting devices (BCDs) are associated with weak mechanical properties, high molecular weight of the degradation products and poor hemocompatibility. Herein, the inert and biocompatible FDA approved poly(2-hydroxyethyl methacrylate) (pHEMA) hydrogel was turned into a degradable material by incorporation of different amounts of a hydrolytically labile crosslinking agent, pentaerythritol tetrakis(3-mercaptopropionate). In situ addition of 1wt.% of oxidized graphene-based materials (GBMs) with different lateral sizes/thicknesses (single-layer graphene oxide and oxidized forms of few-layer graphene materials) was performed to enhance the mechanical properties of hydrogels. An ultimate tensile strength increasing up to 0.2 MPa (293% higher than degradable pHEMA) was obtained using oxidized few-layer graphene with 5 µm lateral size. Moreover, the incorporation of GBMs has demonstrated to simultaneously tune the degradation time, which ranged from 2 to 4 months. Notably, these features were achieved keeping not only the intrinsic properties of inert pHEMA regarding water uptake, wettability and cytocompatibility (short and long term), but also the non-fouling behavior towards human cells, platelets and bacteria. This new pHEMA hydrogel with degradation and biomechanical performance tuned by GBMs, can therefore be envisioned for different applications in tissue engineering, particularly for BCDs where non-fouling character is essential. STATEMENT OF SIGNIFICANCE: Suitable mechanical properties, low molecular weight of the degradation products and hemocompatibility are key features in degradable blood contacting devices (BCDs), and pave the way for significant improvement in the field. In here, a hydrogel with outstanding anti-adhesiveness (pHEMA) provides hemocompatibility, the presence of a degradable crosslinker provides degradability, and incorporation of graphene oxide reestablishes its strength, allowing tuning of both degradation and mechanical properties. Notably, these hydrogels simultaneously provide suitable water uptake, wettability, cytocompatibility (short and long term), no acute inflammatory response, and non-fouling behavior towards endothelial cells, platelets and bacteria. Such results highlight the potential of these hydrogels to be envisioned for applications in tissue engineered BCDs, namely as small diameter vascular grafts.
Assuntos
Grafite , Hidrogéis , Humanos , Hidrogéis/farmacologia , Poli-Hidroxietil Metacrilato , Grafite/farmacologia , Células Endoteliais , Materiais Biocompatíveis/farmacologia , ÁguaRESUMO
Psidium guajava L. (guava) leaves have demonstrated their in vitro and in vivo effect against diabetes mellitus (DM). However, there is a lack of literature concerning the effect of the individual phenolic compounds present in the leaves in DM disease. The aim of the present work was to identify the individual compounds in Spanish guava leaves and their potential contribution to the observed anti-diabetic effect. Seventy-three phenolic compounds were identified from an 80% ethanol extract of guava leaves by high performance liquid chromatography coupled to electrospray ionization and quadrupole time-of-flight mass spectrometry. The potential anti-diabetic activity of each compound was evaluated with the DIA-DB web server that uses a docking and molecular shape similarity approach. The DIA-DB web server revealed that aldose reductase was the target protein with heterogeneous affinity for compounds naringenin, avicularin, guaijaverin, quercetin, ellagic acid, morin, catechin and guavinoside C. Naringenin exhibited the highest number of interactions with target proteins dipeptidyl peptidase-4, hydroxysteroid 11-beta dehydrogenase 1, aldose reductase and peroxisome proliferator-activated receptor. Compounds catechin, quercetin and naringenin displayed similarities with the known antidiabetic drug tolrestat. In conclusion, the computational workflow showed that guava leaves contain several compounds acting in the DM mechanism by interacting with specific DM protein targets.