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BACKGROUND: In Parkinson's patients, intestinal dysbiosis can occur years before clinical diagnosis, implicating the gut and its microbiota in the disease. Recent evidence suggests the gut microbiota may trigger body-first Parkinson Disease (PD), yet the underlying mechanisms remain unclear. This study aims to elucidate how a dysbiotic microbiome through intestinal immune alterations triggers PD-related neurodegeneration. METHODS: To determine the impact of gut dysbiosis on the development and progression of PD pathology, wild-type male C57BL/6 mice were transplanted with fecal material from PD patients and age-matched healthy donors to challenge the gut-immune-brain axis. RESULTS: This study demonstrates that patient-derived intestinal microbiota caused midbrain tyrosine hydroxylase positive (TH +) cell loss and motor dysfunction. Ileum-associated microbiota remodeling correlates with a decrease in Th17 homeostatic cells. This event led to an increase in gut inflammation and intestinal barrier disruption. In this regard, we found a decrease in CD4 + cells and an increase in pro-inflammatory cytokines in the blood of PD transplanted mice that could contribute to an increase in the permeabilization of the blood-brain-barrier, observed by an increase in mesencephalic Ig-G-positive microvascular leaks and by an increase of mesencephalic IL-17 levels, compatible with systemic inflammation. Furthermore, alpha-synuclein aggregates can spread caudo-rostrally, causing fragmentation of neuronal mitochondria. This mitochondrial damage subsequently activates innate immune responses in neurons and triggers microglial activation. CONCLUSIONS: We propose that the dysbiotic gut microbiome (dysbiome) in PD can disrupt a healthy microbiome and Th17 homeostatic immunity in the ileum mucosa, leading to a cascade effect that propagates to the brain, ultimately contributing to PD pathophysiology. Our landmark study has successfully identified new peripheral biomarkers that could be used to develop highly effective strategies to prevent the progression of PD into the brain.
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Disbiose , Microbioma Gastrointestinal , Camundongos Endogâmicos C57BL , Doença de Parkinson , Animais , Microbioma Gastrointestinal/fisiologia , Doença de Parkinson/metabolismo , Doença de Parkinson/microbiologia , Doença de Parkinson/imunologia , Camundongos , Disbiose/imunologia , Masculino , Humanos , Transplante de Microbiota FecalRESUMO
Whether small number magnitudes are inherently represented as lying to the left of larger ones, the space-number association (SNA), is an important issue in mathematical cognition. In this fMRI study, we used a go/no-go implicit association task to investigate the brain activity and functional connectivity underlying the SNA. Arabic digits lower or higher than 5 and left- or right-pointing arrows were alternated as central targets. In a single-code task condition, participants responded to a specific number magnitude and to all arrows or to a specific arrow direction and to all number magnitudes. In a joint-code (JC) condition, responses were provided after congruent, for example, "go when a number is lower than 5 or an arrow points left," or incongruent, for example, "go when a number is lower than 5 or an arrow points right," SNAs. The SNA was only found in the JC condition, where responses were faster with congruent instructions. Analyses of fMRI functional connectivity showed that the SNA was matched with enhanced excitatory inputs from ACC, the left TPJ, and the left inferior frontal gyrus to the left and right intraparietal sulcus (IPS). Incongruent JC trials were associated with enhanced excitatory modulation from ACC to the left and right IPS. These results show that the SNA is associated with enhanced activation of top-down brain control and changes in the functional interaction between the left and right IPS. We conclude that the SNA does not depend on an inherent and bottom-up spatial coding of number magnitudes.
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A 37-year-old man presented with chronic cavitary pulmonary aspergillosis and hemoptysis refractory to systemic antifungal therapy with voriconazole and bronchial artery embolization. Surgical excision was unfeasible due to the patient's refusal of blood transfusions. Ten sessions of intracavitary instillation of amphotericin B via flexible bronchoscopy were then performed. Hemoptysis cessation and aspergilloma resolution were achieved, with no toxicity or side effects, and the clinical benefits were sustained at six months of follow-up.
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Humans use space to think of and communicate the flow of time. This spatial representation of time is influenced by cultural habits so that in left-to-right reading cultures, short durations and past events are mentally positioned to the left of long durations and future events. The STEARC effect (Space Temporal Association of Response Codes) shows a faster classification of short durations/past events with responses on the left side of space and of long durations/future events with responses on the right side. We have recently showed that during the classification of time durations, space is a late heuristic of time because in this case, the STEARC appears only when manual responses are slow, not when they are fast. Here, we wished to extend this observation to the semantic classification of words as referring to the 'past' or the 'future'. We hypothesised that the semantic processing of 'past' and 'future' concepts would have engaged slower decision processes than the classification of short versus long time durations. According to dual-route models of conflict tasks, if the task-dependent classification/decision process were to proceed relatively slowly, then the effects of direct activation of culturally preferred links between stimulus and response (S-R), i.e., past/left and future/right in the case of the present task, should attain higher amplitudes before the instruction-dependent correct response is selected. This would imply that, at variance with the faster classification of time durations, during the slower semantic classification of time concepts, in incongruent trials, the direct activation of culturally preferred S-R links should introduce significant reaction time (RT) costs and a corresponding STEARC at the fastest manual responses in the experiment too. The study's results confirmed this hypothesis and showed that in the classification of temporal words, the STEARC also increased as a function of the length of RTs. Taken together, the results from sensory duration and semantic classification STEARC tasks show that the occurrence, strength and time course of the STEARC varies significantly as a function of the speed and level of cognitive processing required in the task.
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Tempo de Reação , Semântica , Percepção Espacial , Percepção do Tempo , Humanos , Feminino , Masculino , Orientação , Adulto Jovem , Adulto , Tomada de Decisões , Leitura , Reconhecimento Visual de Modelos/fisiologia , Lateralidade Funcional , AtençãoRESUMO
Cholinergic (Ach), Noradrenergic (NE), and Dopaminergic (DA) pathways play an important role in the regulation of spatial attention. The same neurotransmitters are also responsible for inter-individual differences in temperamental traits. Here we explored whether biologically defined temperamental traits determine differences in the ability to orient spatial attention as a function of the probabilistic association between cues and targets. To this aim, we administered the Structure of Temperament Questionnaire (STQ-77) to a sample of 151 participants who also performed a Posner task with central endogenous predictive (80 % valid/20 % invalid) or non-predictive cues (50 % valid/50 % invalid). We found that only participants with high scores in Plasticity and Intellectual Endurance showed a selective abatement of attentional costs with non-predictive cues. In addition, stepwise regression showed that costs in the non-predictive condition were negatively predicted by scores in Plasticity and positively predicted by scores in Probabilistic Thinking. These results show that stable temperamental characteristics play an important role in defining the inter-individual differences in attentional behaviour, especially in the presence of different probabilistic organisations of the sensory environment. These findings emphasize the importance of considering temperamental and personality traits in social and professional environments where the ability to control one's attention is a crucial functional skill.
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Atenção , Temperamento , Humanos , Temperamento/fisiologia , Atenção/fisiologia , Transtornos do Humor , Dopamina , Norepinefrina/fisiologia , Sinais (Psicologia)RESUMO
Left-to-right readers classify faster past events with motor responses on the left side of space and future events with responses on the right side. This suggests a left-to-right spatial organization in the mental representation of time. Here, we show that the significance and reliability of this representation are linked to the joint use of temporal and spatial codes in the task at hand. In a first unimanual Go/No-Go Implicit Association Test (IAT), attending selectively to "past" or to "future" words did not activate corresponding "left" or "right" spatial concepts and vice versa. In a second IAT, attending to both temporal (i.e., "past" and "future") words and spatial targets (i.e., "left" and "right") pointing arrows produced faster responses for congruent rather than incongruent combinations of temporal and spatial concepts in task instructions (e.g., congruent = "Go with past words and left-pointing arrows"; incongruent = "Go with past words and right-pointing arrows"). This effect increased markedly in a STEARC task where spatial codes defined the selection between "left-side" and "right-side" button presses that were associated with "past" and "future" words. Two control experiments showed only partial or unreliable space-time congruency effects when (a) participants attended to superordinate semantic codes that included both spatial "left"/"right" or temporal "past/future" subordinate codes; (b) a primary speeded response was assigned to one dimension (e.g., "past vs. future") and a nonspeeded one to the other dimension (e.g., "left" vs. "right"). These results help to define the conditions that trigger a stable and reliable spatial representation of time-related concepts.
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Percepção Espacial , Percepção do Tempo , Humanos , Tempo de Reação/fisiologia , Reprodutibilidade dos Testes , Percepção Espacial/fisiologia , Percepção do Tempo/fisiologia , SemânticaRESUMO
Senotherapy, a promising therapeutic strategy, has drawn a lot attention recently due to its potential for combating cancer. Senotherapy refers to the targeting of senescent cells to restore tissue homeostasis and mitigate the deleterious effects associated with senescence. Senolytic drugs represent a promising avenue in cancer treatment, with the potential to target and modulate senescent cells to improve patient outcomes. The review highlights the intricate interplay between the senescence-associated secretory phenotype (SASP) and the tumor microenvironment, emphasizing the role of senescent cells in promoting chronic inflammation, immune evasion, and tumor-cell proliferation. It then explores the potential of senotherapy as a novel strategy for cancer therapy. This review addresses the emerging evidence on the combination of senotherapy with conventional cancer treatments, such as chemotherapy and immunotherapy.
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To get a concrete representation of its intangible flow, culture frames elapsing time along spatially oriented mental or graphical lines, which are organised according to reading habits, from left to right in western cultures. One of the strongest evidence for this spatial representation of time is the STEARC effect (Spatial-Temporal Association of Response Codes), which consists of faster coding of "short" durations with motor responses in the left side of space and of "long" durations with responses in the right side. Here, we investigated the STEARC as a function of response speed in two different experiments in healthy participants. Surprisingly, in both sub- and supra-second ranges, we found the STEARC only when decisions on time durations were slow, while no spatial representation of time was present with fast decisions. This first demonstrates that space slowly takes over faster non-spatial processing of time flow and that it is possible to empirically separate the behavioural manifestations of the non-spatial and the nurtured spatial mechanisms of time coding.
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Heurística , Percepção Espacial , Humanos , Percepção Espacial/fisiologia , Tempo de Reação/fisiologia , Fatores de TempoRESUMO
OBJECTIVE: Idiopathic Parkinson's disease (PD) is characterised by alpha-synuclein (aSyn) aggregation and death of dopaminergic neurons in the midbrain. Recent evidence posits that PD may initiate in the gut by microbes or their toxins that promote chronic gut inflammation that will ultimately impact the brain. In this work, we sought to demonstrate that the effects of the microbial toxin ß-N-methylamino-L-alanine (BMAA) in the gut may trigger some PD cases, which is especially worrying as this toxin is present in certain foods but not routinely monitored by public health authorities. DESIGN: To test the hypothesis, we treated wild-type mice, primary neuronal cultures, cell lines and isolated mitochondria with BMAA, and analysed its impact on gut microbiota composition, barrier permeability, inflammation and aSyn aggregation as well as in brain inflammation, dopaminergic neuronal loss and motor behaviour. To further examine the key role of mitochondria, we also determined the specific effects of BMAA on mitochondrial function and on inflammasome activation. RESULTS: BMAA induced extensive depletion of segmented filamentous bacteria (SFB) that regulate gut immunity, thus triggering gut dysbiosis, immune cell migration, increased intestinal inflammation, loss of barrier integrity and caudo-rostral progression of aSyn. Additionally, BMAA induced in vitro and in vivo mitochondrial dysfunction with cardiolipin exposure and consequent activation of neuronal innate immunity. These events primed neuroinflammation, dopaminergic neuronal loss and motor deficits. CONCLUSION: Taken together, our results demonstrate that chronic exposure to dietary BMAA can trigger a chain of events that recapitulate the evolution of the PD pathology from the gut to the brain, which is consistent with 'gut-first' PD.
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Microbioma Gastrointestinal , Doença de Parkinson , Camundongos , Animais , Microbioma Gastrointestinal/fisiologia , Mesencéfalo/metabolismo , Mesencéfalo/patologia , Doença de Parkinson/metabolismo , Inflamação/metabolismo , Mitocôndrias/metabolismoRESUMO
Ageing is characterised by the accumulation of molecular and cellular damage through time, leading to a decline in physical and mental abilities. Currently, society has experienced a rapid increase in life expectancy, which has led to an increase in age-associated diseases. Therefore, it is crucial to study the process of ageing to guarantee the best conditions in the final stages of life. In recent years, interest has increased in a myokine known as irisin, which is secreted during physical exercise. This polypeptide hormone is produced by various organs, mainly muscle, and once it is released into the blood, it performs a wide variety of functions that are involved in metabolic control and may be relevant during some of the diseases associated with ageing. The aim of this review is to highlight the recent studies of irisin, such as its mechanism of expression, blood release, distribution, tissue target and participation in various cellular metabolic reactions and the relationship with key anti-ageing pathways such as adenosine monophosphate-activated protein kinase, silent information regulator T 1, autophagy and telomerase. In conclusion, irisin is a key player during the ageing process and it could be a novel target molecule for the therapeutic approach to boost longevity pathways. However, more research will be necessary to use this promising hormone for this gain.
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Fibronectinas , Longevidade , Humanos , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Autofagia , Fibronectinas/genética , Fibronectinas/metabolismo , Longevidade/genética , Sirtuína 1/genética , Sirtuína 1/metabolismo , Telomerase/genética , Telomerase/metabolismoRESUMO
Background: Frailty is a common geriatric syndrome, associated with adverse clinical outcomes. Nevertheless, studies about frailty in continuous care units are scarce. In this way, this study aimed to assess frailty in older patients admitted in convalescence units (CUs) and analyze its association with demographic, social and clinical characteristics. Methods: This cross-sectional study included older patients admitted in eight CUs of the Integrated Continued Care National Network in Northern Portugal. Exclusion criteria were: total ≤ 11 in Glasgow coma scale, < 10 in mini-mental state examination or being unable to communicate. A comprehensive protocol was administered to assess health-related and lifestyle characteristics, comorbidity, dependence on activities of daily living (ADL), depressive and anxiety symptoms, cognition, and socio-familial risk. Frailty was assessed by Tilburg frailty indicator (TFI). Results: A sample of 165 patients was included (median age = 77; 65% female), with 80% classified as frail, mostly women (P = 0.002), widowed (P = 0.016), shorter (P = 0.005), feeling more tired (P < 0.005) and with less energy (P < 0.005). Also, these patients reported more vision problems (P = 0.006), difficulties in walking (P = 0.022) and climbing stairs (P = 0.029), pain (P = 0.004), falls (P = 0.046), non-alcohol use (P = 0.043) and non-physical activity (P = 0.032). Frail patients had a higher number of previous hospitalizations (P = 0.018), comorbidity (P = 0.006), dependence on instrumental (P < 0.001) and basic (P = 0.006; P < 0.001) ADL, depressive (P < 0.001) and anxiety (P = 0.002) symptoms. After adjusting for covariates, frailty was associated with females (adjusted odds ratio (aOR) = 4.45, P = 0.011), vascular disease (aOR = 4.40, P = 0.040), vision problems (aOR = 10.85, P < 0.001), high dependency on instrumental ADL (aOR = 0.74, P = 0.002), and depressive symptoms (aOR = 1.37, P = 0.001). Conclusions: Frailty is high among older patients in CUs, particularly in females, with vascular disease, vision problems, instrumental ADL dependence and depressive symptoms. Thus, frailty should be screened, and preventive and therapeutic measures should be considered for those at high risk, in order to minimize possible negative consequences.
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BACKGROUND: COVID-19 is caused by SARS-CoV-2 infection and has reached pandemic proportions. Since then, several clinical characteristics have been associated with poor outcomes. This study aimed to describe the morbidity profile of COVID-19 deaths in Portugal. METHODS: A study was performed including deaths certificated in Portugal with "COVID-19" (ICD-10: U07.1 or U07.2) coded as the underlying cause of death from the National e-Death Certificates Information System between 16 March and 31 December 2020. Comorbidities were derived from ICD-10 codes using the Charlson and Elixhauser indexes. The resident Portuguese population estimates for 2020 were used. RESULTS: The study included 6701 deaths (death rate: 65.1 deaths/100,000 inhabitants), predominantly males (72.1). The male-to-female mortality ratio was 1.1. The male-to-female mortality rate ratio was 1.2; however, within age groups, it varied 5.0-11.4-fold. COVID-19 deaths in Portugal during 2020 occurred mainly in individuals aged 80 years or older, predominantly in public healthcare institutions. Uncomplicated hypertension, uncomplicated diabetes mellitus, congestive heart failure, renal failure, cardiac arrhythmias, dementia, and cerebrovascular disease were observed among COVID-19 deceased patients, with prevalences higher than 10%. A high prevalence of zero morbidities was registered using both the Elixhauser and Charlson comorbidities lists (above 40.2%). Nevertheless, high multimorbidity was also identified at the time of COVID-19 death (about 36.5%). Higher multimorbidity levels were observed in men, increasing with age up to 80 years old. Zero-morbidity prevalence and high multimorbidity prevalences varied throughout the year 2020, seemingly more elevated in the mortality waves' peaks, suggesting variation according to the degree of disease incidence at a given period. CONCLUSIONS: This study provides detailed sociodemographic and clinical information on all certificated deaths from COVID-19 in Portugal during 2020, showing complex and extreme levels of morbidity (zero-morbidity vs. high multimorbidity) dynamics during the first year of the pandemic in Portugal.
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BACKGROUND: Metastasis to the brain is a major challenge with poor prognosis. The blood-brain barrier (BBB) is a significant impediment to effective treatment, being intact during the early stages of tumor development and heterogeneously permeable at later stages. Intravenous injection of tumor necrosis factor (TNF) selectively induces BBB permeabilization at sites of brain micrometastasis, in a TNF type 1 receptor (TNFR1)-dependent manner. Here, to enable clinical translation, we have developed a TNFR1-selective agonist variant of human TNF that induces BBB permeabilization, while minimizing potential toxicity. METHODS: A library of human TNF muteins (mutTNF) was generated and assessed for binding specificity to mouse and human TNFR1/2, endothelial permeabilizing activity in vitro, potential immunogenicity, and circulatory half-life. The permeabilizing ability of the most promising variant was assessed in vivo in a model of brain metastasis. RESULTS: The primary mutTNF variant showed similar affinity for human TNFR1 than wild-type human TNF, similar affinity for mouse TNFR1 as wild-type mouse TNF, undetectable binding to human/mouse TNFR2, low potential immunogenicity, and permeabilization of an endothelial monolayer. Circulatory half-life was similar to mouse/human TNF and BBB permeabilization was induced selectively at sites of micrometastases in vivo, with a time window of ≥24 hours and enabling delivery of agents within a therapeutically relevant range (0.5-150 kDa), including the clinically approved therapy, trastuzumab. CONCLUSIONS: We have developed a clinically translatable mutTNF that selectively opens the BBB at micrometastatic sites, while leaving the rest of the cerebrovasculature intact. This approach will open a window for brain metastasis treatment that currently does not exist.
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Barreira Hematoencefálica , Neoplasias Encefálicas , Animais , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Camundongos , Trastuzumab , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Fluid therapy in pediatric patients plays a fundamental role in perioperative anesthetic management. Planning of all surgical procedures must take into account the fluid therapy necessary to maintain both the basal metabolic needs and the losses de- rived from surgery. Generally, maintenance fluid therapy is performed with balanced hydro electrolytic solutions plus glucose (although the latter may not be necessary in most pediatric surgeries), and replacement fluid therapy with glucose-free solutions, with crystalloids being the most frequently used. Surgeries that present significant losses require a replacement fluid plan that allows maintaining an adequate intravascular volume, allowing an appropriate return and ventricular filling, as well as adequate tissue transport of oxygen. When necessary, transfusion of blood products should be aimed at reestablishing the necessary con- ditions to maintain homeostasis during the perioperative period.
La terapia de aporte de fluidos en pediatría es una parte fundamental del manejo anestésico perioperatorio. La planificación de todo procedimiento quirúrgico debe considerar el aporte necesario para mantener tanto las necesidades metabólicas basales como las pérdidas derivadas de la cirugía. En general, la terapia de mantención se efectúa con soluciones hidroelectrolíticas balanceadas más glucosa (aunque en la mayoría de las cirugías pediátricas pudiese no ser necesario esto último), y la terapia de reposición con soluciones libres de glucosa, siendo los cristaloides los más frecuentemente utilizados. Cirugías que presentan pérdidas importantes requieren tener un plan de aporte que permita mantener un espacio intravascular adecuado y permita a su vez un adecuado retorno y llenado ventricular, así como un adecuado transporte de oxígeno tisular. Cuando sea necesario, la transfusión de hemoderivados debe estar dirigida a reestablecer las condiciones necesarias para mantener dicho balance y homeostasis durante todo el período perioperatorio.
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Humanos , Criança , Assistência Perioperatória/métodos , Hidratação/métodos , AnestesiaRESUMO
It is debated whether the representation of numbers is endowed with a directional-spatial component so that perceiving small-magnitude numbers triggers leftward shifts of attention and perceiving large-magnitude numbers rightward shifts. Contrary to initial findings, recent investigations have demonstrated that centrally presented small-magnitude and large-magnitude Arabic numbers do not cause leftward and rightward shifts of attention, respectively. Here we verified whether perceiving small or large non-symbolic numerosities (i.e., clouds of dots) drives attention to the left or the right side of space, respectively. In experiment 1, participants were presented with central small (1, 2) vs large-numerosity (8, 9) clouds of dots followed by an imperative target in the left or right side of space. In experiment 2, a central cloud of dots (i.e., five dots) was followed by the simultaneous presentation of two identical dot-clouds, one on the left and one on the right side of space. Lateral clouds were both lower (1, 2) or higher in numerosity (8, 9) than the central cloud. After a variable delay, one of the two lateral clouds turned red and participants had to signal the colour change through a unimanual response. We found that (a) in Experiment 1, the small vs large numerosity of the central cloud of dots did not speed up the detection of left vs right targets, respectively, (b) in Experiment 2, the detection of colour change was not faster in the left side of space when lateral clouds were smaller in numerosity than the central reference and in the right side when clouds were larger in numerosity. These findings show that perceiving non-symbolic numerosity does not cause automatic shifts of spatial attention and suggests no inherent association between the representation of numerosity and that of directional space.
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Percepção Espacial , Humanos , Tempo de ReaçãoRESUMO
Electrophysiological group studies in brain-damaged patients can be run to capture the EEG correlates of specific cognitive impairments. Nonetheless, this procedure is not adequate to characterize the inter-individual variability present in major neuropsychological syndromes. We tested the possibility of getting a reliable individual EEG characterization of deficits of endogenous orienting of spatial attention in right-brain damaged (RBD) patients with left spatial neglect (N+). We used a single-trial topographical analysis (STTA; [39] of individual scalp EEG topographies recorded during leftward and rightward orienting of attention with central cues in RBD patients with and without (N-) neglect and in healthy controls (HC). We found that the STTA successfully decoded EEG signals related to leftward and rightward orienting in five out of the six N+, five out of the six N- patients and in all the six HC. In agreement with findings from conventional average-group studies, successful classifications of EEG signals in N+ were observed during the 400-800 ms period post-cue-onset, which reflects preserved voluntary engagement of attention resources (ADAN component). These results suggest the possibility of acquiring reliable individual EEG profiles of neglect patients.
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Atenção , Transtornos da Percepção/fisiopatologia , Comportamento Espacial , Acidente Vascular Cerebral/complicações , Idoso , Encéfalo/fisiopatologia , Eletroencefalografia , Feminino , Lateralidade Funcional , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos da Percepção/etiologiaRESUMO
Right brain-damaged patients with unilateral spatial neglect fail to explore the left side of space. Recent EEG and clinical evidence suggests that neglect patients might suffer deficits in predictive coding, i.e. in identifying and exploiting probabilistic associations among sensory stimuli in the environment. To gain direct insights on this issue, we focussed on the hierarchical components of predictive coding. We recorded EEG responses evoked by central, left-side or right-side tones that were presented at the end of sequences of four central tones. Left-side and right-side deviant tones produce a pre-attentive Mismatch Negativity that reflects a lower-order prediction error for the 'Local' deviation of the tone at the end of the sequence. Higher-order prediction errors for the frequency of these deviations in the acoustic environment, i.e. 'Global' deviation, are marked by the P3 response. We show that when neglect patients are immersed in an acoustic environment characterized by frequent left-side deviant tones, they display no pre-attentive Mismatch Negativity both for left-side deviant tones and infrequent omissions of the last tone, while they have Mismatch Negativity for infrequent right-side deviant tones. In the same condition, neglect patients show no P300 response to 'Global' prediction errors for deviant tones, including those in the non-neglected right-side, and omissions. In contrast to this, when right-side deviant tones are predominant in the acoustic environment, neglect patients have pre-attentive Mismatch Negativity both for right-side deviant tones and infrequent omissions, while they display no Mismatch Negativity for infrequent left-side deviant tones. Most importantly, in the same condition neglect patients show enhanced P300 response to infrequent left-side deviant tones, notwithstanding that these tones evoked no pre-attentive Mismatch Negativity. This latter finding indicates that 'Global' predictions are independent of 'Local' error signals provided by the Mismatch Negativity. These results qualify deficits of predictive coding in the spatial neglect syndrome and show that neglect patients base their predictive behaviour only on statistical regularities that are related to the frequent occurrence of sensory events on the right side of space.
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Recent evidence confirms that PD is indeed a multifactorial disease with different aetiologies and prodromal symptomatology that likely depend on the initial trigger. New players with important roles as triggers, facilitators and aggravators of the PD neurodegenerative process have re-emerged in the last few years, the microbes. Having evolved in association with humans for ages, microbes and their products are now seen as fundamental regulators of human physiology with disturbances in their balance being increasingly accepted to have a relevant impact on the progression of disease in general and on PD in particular. In this review, we comprehensively address early studies that have directly or indirectly linked bacteria or other infectious agents to the onset and progression of PD, from the earliest suspects to the most recent culprits, the gut microbiota. The quest for effective treatments to arrest PD progression must inevitably address the different interactions between microbiota and human cells, and naturally consider the gut-brain axis. The comprehensive characterization of such mechanisms will help design innovative bacteriotherapeutic approaches to selectively shape the gut microbiota profile ultimately to halt PD progression. The present review describes our current understanding of the role of microorganisms and their endosymbiotic relatives, the mitochondria, in inducing, facilitating, or aggravating PD pathogenesis.
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Microbioma Gastrointestinal , Microbiota , Doença de Parkinson , Encéfalo , Humanos , Doença de Parkinson/terapiaRESUMO
INTRODUCTION: This study aims to describe the translation and adaptation of the European Portuguese Clinical Frailty Scale and assess its convergent validity and test-retest reliability. MATERIAL AND METHODS: This validation study included a sample of elderly people admitted in two convalescence units from the National Network of Integrated Continuous Care in Northern Portugal and followed in two outpatient clinics of social solidarity institutions. Convergent validity of the scale was evaluated, against Tilburg Frailty Indicator. Test-retest reliability, sensitivity and specificity were assessed. RESULTS: Overall, 51 patients were included (mean age = 78 years old). The Clinical Frailty Scale identified 43.1% patients with frailty. Kappa values for test-retest reliability (non-frail/frail) was 1.00. The intraclass correlation coefficient for the 9-point total scale was 0.999. A correlation between Clinical Frailty Scale and Tilburg Frailty Indicator was also found (rs = 0.683; p < 0.001). The Cohen's kappa coefficient was 0.423 in the agreement analysis between these scales. The results for sensitivity and specificity defined that 62.0% of patients were true positives and 81.8% true negatives. The scale accuracy determined by the receiver operating characteristics curve analysis was 0.782. DISCUSSION: This scale showed an excellent test-retest reliability. Robust results on convergent validity were also achieved, with a moderate correlation and agreement with the Tilburg Frailty Indicator, showing good sensitivity and accuracy, as well as high specificity. CONCLUSION: This version has an excellent test-retest reliability and good convergent validity, and is both a reliable and valid test for application in clinical practice for assessing Portuguese elderly population admitted in convalescence units and outpatient clinics.
Introdução: Este estudo tem como objetivo descrever a tradução e adaptação da versão Portuguesa da Clinical Frailty Scale e avaliar a validade convergente e fiabilidade teste-reteste. Material e Métodos: Este estudo de validação incluiu idosos internados em duas unidades de convalescença da Rede Nacional de Cuidados Continuados Integrados no Norte de Portugal e seguidos em consulta de ambulatório de Instituições de solidariedade social. A validade convergente desta escala foi avaliada, comparando-a com o Tilburg Frailty Indicator. A fiabilidade teste-reteste, sensibilidade e especificidade foram testadas. Resultados: Foram incluídos 51 doentes (idade média = 78 anos). A escala identificou 43,1% idosos com fragilidade. Na fiabilidade teste-reteste foi encontrado um kappa = 1 (não-frágil/frágil). O coeficiente de correlação intraclasse para o total da escala de nove pontos foi 0,999. Foi encontrada uma correlação entre a Clinical Frailty Scale e o Tilburg Frailty Indicator (rs = 0,683; p < 0,001). O coeficiente Cohen's kappa foi 0,423 na análise da concordância entre estas escalas. Os resultados de sensibilidade e especificidade definiram que 62,0% dos pacientes eram verdadeiros positivos e 81,8% verdadeiros negativos. A precisão, determinada pela análise da curva de características receptor-operador, foi de 0,782. Discussão: A escala revelou uma excelente fiabilidade teste-reteste, bons resultados de validade convergente, boa correlação e um nível de concordância moderado com o Tilburg Frailty Indicator, demonstrando boa sensibilidade, precisão, e elevada especificidade. Conclusão: Esta versão da escala demonstra excelente fiabilidade teste-reteste e boa validade convergente, sendo um teste fiável e válido para aplicação na prática clínica na avaliação da população idosa portuguesa admitida em unidades de convalescença e em unidades de ambulatório.