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Efeitos dos Canabinoides no Tremor Parkinsoniano e interações medicamentosas: análise por inteligência artificial explicável dos dados Fox Insight

Mon, 01 Dec 2025 00:00:00 GMT

Title: Efeitos dos Canabinoides no Tremor Parkinsoniano e interações medicamentosas: análise por inteligência artificial explicável dos dados Fox Insight Abstract: Parkinson’s disease constitutes the second most prevalent neurodegenerative condition worldwide, affecting 1-2% of the population over 65 years of age, with tremor present in 70% of cases. Conventional pharmacological treatments present limitations in 30-40% of patients, establishing the need for therapeutic alternatives. This thesis aimed to develop an explainable artificial intelligence methodology for personalizing medical cannabis use in treating parkinsonian tremor, quantifying determinants of individual heterogeneity in therapeutic response. The methodology employed analysis based on SHAP (SHapley Additive exPlanations) values applied to 2,616 records from the Fox Insight platform, structured in three progressive datasets: SINGLE (n=973, isolated cannabis), FULL_NUMERICO (n=931, pharmacological groups), and FULL_GFEM (n=931, detailed individual characteristics). Machine learning models achieved elevated performance metrics: SINGLE (LightGBM) with accuracy 96.31%, precision 96.33%, recall 96.31%, F1-score 96.31%, and specificity 96.03%; FULL_NUMERICO (LightGBM) with accuracy 97.42%, precision 97.47%, recall 97.42%, F1-score 97.42%, and specificity 97.07%; FULL_GFEM (XGBoost) with accuracy 97.42%, precision 97.54%, recall 97.42%, F1-score 97.42%, and specificity 96.91%, demonstrating that interpretability does not compromise predictive performance when architecture is adequately designed. Results quantified eight main findings: (1) pronounced sexual dimorphism, with women presenting mean SHAP values of +1.52 ± 0.48 (improvement rate 94.1%) versus men -0.93 ± 0.37 (rate 38.5%), establishing a magnitude of 2.44x in the probability of favorable response; (2) identification of six distinct profiles through clustering, with 55% of patients presenting elevated improvement rates (89% to 100%) and SHAP values between +1.94 and +2.57; (3) non-linear inverted-U age pattern, with critical group 60-70 years (n=559, 60% of sample) presenting worse response (rate 38.8%) and partial recovery in 70-80 years (rate 76.2%, n=181); (4) hierarchy of administration routes quantified by MASV (Mean Absolute SHAP Value): oil (0.705) > sublingual (0.4959) > food (0.657 Class 1), demonstrating importance superior to dose; (5) bifasic optimal therapeutic windows for THC (1.5-2.5 mg/day, MASV = 0.2888) and CBD (2-4 mg/day, MASV = 0.2654), empirically validating that supra-therapeutic doses reduce efficacy; (6) quantified synergy with MAO-B inhibitors (MASV = 0.4485), superior to interactions with levodopa (MASV = 0.2506) and other dopaminergics (MASV = 0.2454); (7) moderate optimal frequency of 3-5 times/week, superior to continuous daily use; (8) therapeutic learning curve with optimization in 2-3 years and possible tolerance after >3 years. Findings were operationalized in a clinical nomogram that stratifies patients into five predictive categories, with 87.3% concordance with phenotypic clusters. Computational analysis through clustering identified difference in improvement rates between subgroups with elevated response (89-100%, n=513) and general population (66.4%, n=931), suggesting potential for therapeutic personalization based on identifiable clinical characteristics, hypothesis requiring confirmation in future clinical studies. This investigation establishes a new methodological standard for research in precision neurological medicine, providing computational tools and quantitative knowledge for prospective identification of subgroups with high probability of benefit, individualized therapeutic regimen optimization, and establishment of expectations based on measurable patient characteristics.

Avaliação da atividade eletromiográfica de músculos do core no exercício prancha ventral até a exaustão com e sem exergame plankpad

Mon, 04 May 2026 00:00:00 GMT

Title: Avaliação da atividade eletromiográfica de músculos do core no exercício prancha ventral até a exaustão com e sem exergame plankpad Abstract: Core training plays an important role in quality of life, especially in reducing the prevalence of low back pain. Recently, exergames such as Plankpad have been developed to improve adherence to physical training and rehabilitation programs focused on core muscle strengthening. However, no studies have analyzed electromyographic (EMG) activity during the ventral plank (VP) exercise with and without exergame, including time-domain and frequency-domain analysis as well as muscle co-contraction. This study aimed to investigate the effects of incorporating the Plankpad exergame on core muscle EMG activity during the VP exercise until exhaustion. Fifteen young, healthy, physically active men with no history of low back pain participated. Participants performed the VP exercise until exhaustion under five conditions: stable ground (VP-GR), Plankpad platform without game (VP-PP), and Plankpad platform with the Fruit Splicer game at easy (VP-EA), medium (VP-ME), and hard (VP-HA) levels. EMG signals were collected from the rectus abdominis (RA), external oblique (EO), internal oblique (IO), erector spinae (ES), and multifidus (MU) muscles, along with time to exhaustion and rating of perceived exertion (RPE). Results showed progressive increases in RMS and decreases in median frequency (MF) over time in all exercises, indicating peripheral neuromuscular fatigue, with no significant differences among the five conditions for most parameters. Local co-contraction (IO/MU) was significantly higher in VP-PP compared to VP EA and decreased with fatigue across all exercises. Time to exhaustion and RPE were similar among conditions. Correlations between RPE and EMG parameters were weak to moderate. We conclude that the Plankpad exergame, at easy, medium, and hard levels, does not increase electromyographic activation, spectral fatigue, time to exhaustion, or RPE compared to traditional plank exercise in young healthy trained men.

Avaliação dos protocolos de morte encefálica

Mon, 27 Oct 2025 00:00:00 GMT

Title: Avaliação dos protocolos de morte encefálica Abstract: The inherent complexity and urgency of diagnosing Brain Death (BD) constitute a persistent challenge in Intensive Care Units (ICU), representing a critical factor for the success of the National Transplant Policy (PNT). BD, defined as the irreversible cessation of all brain functions, is the legal premise of death authorizing organ removal, in accordance with Law No. 9,434/97 and CFM Resolution No. 2,173/17. The ethical and logistical imperative demands absolute celerity and safety, given that delay compromises organ viability. Furthermore, initiating the BD diagnostic protocol entails a fatal prognosis, culminating either in BD confirmation or Cardiac Arrest (PCR). With the objective of optimizing the diagnosis and the rational use of ancillary tests, such as the Electroencephalogram (EEG), this thesis sought to establish a robust predictive score capable of differentiating progression to BD from Death by Cardiac Arrest (PCR) in neurocritical patients. The study was conducted as a retrospective cohort analysis, approved by the Ethics Committee (CEP) of the Universidade Federal de Uberlândia (UFU), utilizing an Analytical Sample of N=66 patients and applying Binary Logistic Regression to identify independent predictive factors. The statistical model confirmed that the outcome is primarily determined by the initial neurovascular severity. Two clinical factors were identified as the most robust predictors for the outcome of Brain Death: the initial Glasgow Coma Scale (GCS) score and the Use of Vasoactive Drugs (DVA). The initial GCS score proved to be the strongest independent predictor (OR = 1.70; p=0.002), indicating that the BD outcome is intrinsically linked to catastrophic initial neurological injury. Complementarily, the use of DVA was a strong predictor of BD (OR = 0.04; p=0.031), as the need for pressure support (observed in approximately 95% of BD cases) is a robust marker of neurogenic shock and brainstem failure, reducing the chance of death by PCR by 96%. Univariate analyses corroborated that Traumatic Brain Injury (TBI) etiology was significantly more prevalent in the BD Group (approximately 44% vs. 0% in the PCR Group; p=0.022), reinforcing the epidemiological profile of high-impact acute lesions. Furthermore, the extremely low rate of Cardiac Arrest in the BD Group (approximately 1.7%; p<0.001) attested to the high quality of intensive clinical management, maintaining organ viability until the legal declaration of death. Regarding ancillary testing, Quantitative EEG (QEEG) analysis in selected cases demonstrated that progression to BD is marked by a profound electrophysiological disorganization, featuring an inversion in power patterns and extreme, dysregulated variability of electrical activity. This reinforces the potential of EEG, due to its non-invasive and cost-effective nature, as an ideal tool within the reality of the public health system (SUS). The main practical contribution of this thesis resides in the proposition of the Predictive Triage Model (GCS + DVA). This model allows for the quicker and more focused activation of the BD protocol and complementary examinations, particularly concentrating on EEG use. This optimization directly contributes to maintaining organ viability. In summary, the work demonstrates that the integration of methodological rigor from data science with clinical physiology establishes powerful tools to refine the diagnosis of Brain Death, ensuring the excellence and efficiency demanded by the ethical and legal imperative

Cálculo de blindagem em medicina nuclear no Brasil: diretrizes, metodologia e avaliação do impacto do uso de fatores não usuais na espessura final

Tue, 10 Feb 2026 00:00:00 GMT

Title: Cálculo de blindagem em medicina nuclear no Brasil: diretrizes, metodologia e avaliação do impacto do uso de fatores não usuais na espessura final Abstract: Radiation shielding calculation reports are a legal requirement and a fundamental prerequisite for obtaining authorization for the construction and operation of nuclear medicine services in Brazil. Despite their regulatory and technical relevance, the national and international literature presents fragmented approaches, with gaps in the methodological organization of shielding calculations. This thesis is characterized as applied regulatory research, aiming to consolidate and structure an integrated methodology for radiation shielding calculations in nuclear medicine services, adapted to the Brazilian regulatory and operational context. The work is based on a critical compilation of the specialized literature, the analysis of consolidated references, and the practical application of the proposed methodology to representative scenarios, encompassing diagnostic and therapeutic environments, multiple dose contributions, and hybrid systems. Non-standard factors, often treated in a simplified manner in conventional methods, are discussed and evaluated, including the definition of the critical group, the customization of occupancy factors, the integrated consideration of multiple dose contributions, and the integration between different diagnostic modalities. It is demonstrated that decisions usually regarded as secondary may lead to significant variations in the final shielding thickness, affecting both radiological optimization and the technical and economic feasibility of projects, while maintaining compliance with dose limits established by regulations. The main contribution of this work lies in the compilation, organization, and critical systematization of concepts, parameters, and formulations already consolidated in the literature, reinterpreted in light of current national legislation and accumulated practical experience. By explicitly addressing underexplored factors and discussing their implications for shielding calculations, this thesis broadens the scope of traditional approaches and provides support for more realistic, context-aware designs aligned with the actual operating conditions of nuclear medicine services, while also serving as a technical reference for professionals in the field and for regulatory assessment.