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1.
Front Comput Neurosci ; 18: 1342985, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39081659

RESUMO

Scale-free brain activity, linked with learning, the integration of different time scales, and the formation of mental models, is correlated with a metastable cognitive basis. The spectral slope, a key aspect of scale-free dynamics, was proposed as a potential indicator to distinguish between different sleep stages. Studies suggest that brain networks maintain a consistent scale-free structure across wakefulness, anesthesia, and recovery. Although differences in anesthetic sensitivity between the sexes are recognized, these variations are not evident in clinical electroencephalographic recordings of the cortex. Recently, changes in the slope of the power law exponent of neural activity were found to correlate with changes in Rényi entropy, an extended concept of Shannon's information entropy. These findings establish quantifiers as a promising tool for the study of scale-free dynamics in the brain. Our study presents a novel visual representation called the Rényi entropy-complexity causality space, which encapsulates complexity, permutation entropy, and the Rényi parameter q. The main goal of this study is to define this space for classical dynamical systems within theoretical bounds. In addition, the study aims to investigate how well different time series mimicking scale-free activity can be discriminated. Finally, this tool is used to detect dynamic features in intracranial electroencephalography (iEEG) signals. To achieve these goals, the study implementse the Bandt and Pompe method for ordinal patterns. In this process, each signal is associated with a probability distribution, and the causal measures of Rényi entropy and complexity are computed based on the parameter q. This method is a valuable tool for analyzing simulated time series. It effectively distinguishes elements of correlated noise and provides a straightforward means of examining differences in behaviors, characteristics, and classifications. For the iEEG experimental data, the REM state showed a greater number of significant sex-based differences, while the supramarginal gyrus region showed the most variation across different modes and analyzes. Exploring scale-free brain activity with this framework could provide valuable insights into cognition and neurological disorders. The results may have implications for understanding differences in brain function between the sexes and their possible relevance to neurological disorders.

2.
Front Oncol ; 14: 1378549, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38846977

RESUMO

Introduction: Cervical cancer (CC) is the fourth most prevalent female cancer globally. Understanding its epidemiology is crucial for devising practical strategies suited to geographic and social contexts to attain the global eradication of CC. Hence, this study examined the latest evidence of risk factors contributing to CC development. Methods: An independent literature search was conducted on PubMed using MESH terms. The primary sources were meta-analyses published from 2010 to 2023, which detail updated evidence on risk factors associated with CC. Additionally, the quality of the evidence was evaluated using the GRADE system and recommendations were made accordingly. Results: The main risk factors related to the cause of CC include co-infections with other sexually transmitted infections, genetic markers, cervicovaginal microbiota, nutritional factors, comorbidities that affect the immune response, smoking, and the use of hormonal contraceptives with a quality evidence based on the GRADE scale moderate. Conclusions: Since the necessary cause for CC is persistent cervicovaginal HPV, all the risk factors implicated in the causality of CC act as non-independent cofactors that increase the risk of CC. Thus, changes in public policies aimed at addressing these risk factors are highly recommended and can substantially decrease the risk of CC.

3.
Brain Sci ; 14(5)2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38790421

RESUMO

Information theory explains how systems encode and transmit information. This article examines the neuronal system, which processes information via neurons that react to stimuli and transmit electrical signals. Specifically, we focus on transfer entropy to measure the flow of information between sequences and explore its use in determining effective neuronal connectivity. We analyze the causal relationships between two discrete time series, X:=Xt:t∈Z and Y:=Yt:t∈Z, which take values in binary alphabets. When the bivariate process (X,Y) is a jointly stationary ergodic variable-length Markov chain with memory no larger than k, we demonstrate that the null hypothesis of the test-no causal influence-requires a zero transfer entropy rate. The plug-in estimator for this function is identified with the test statistic of the log-likelihood ratios. Since under the null hypothesis, this estimator follows an asymptotic chi-squared distribution, it facilitates the calculation of p-values when applied to empirical data. The efficacy of the hypothesis test is illustrated with data simulated from a neuronal network model, characterized by stochastic neurons with variable-length memory. The test results identify biologically relevant information, validating the underlying theory and highlighting the applicability of the method in understanding effective connectivity between neurons.

4.
Heliyon ; 10(7): e28936, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38601536

RESUMO

Obesity is currently one of the most alarming pathological conditions due to the progressive increase in its prevalence. In the last decade, it has been associated with fine particulate matter suspended in the air (PM2.5). The purpose of this study was to explore the mechanistic interaction of PM2.5 with a high-fat diet (HFD) through the differential regulation of transcriptional signatures, aiming to identify the association of these particles with metabolically abnormal obesity. The research design was observational, using bioinformatic methods and an explanatory approach based on Rothman's causal model. We propose three new transcriptional signatures in murine adipose tissue. The sum of transcriptional differences between the group exposed to an HFD and PM2.5, compared to the control group, were 0.851, 0.265, and -0.047 (p > 0.05). The HFD group increased body mass by 20% with two positive biomarkers of metabolic impact. The group exposed to PM2.5 maintained a similar weight to the control group but exhibited three positive biomarkers. Enriched biological pathways (p < 0.05) included PPAR signaling, small molecule transport, adipogenesis genes, cytokine-cytokine receptor interaction, and HIF-1 signaling. Transcriptional regulation predictions revealed CpG islands and common transcription factors. We propose three new transcriptional signatures: FAT-PM2.5-CEJUS, FAT-PM2.5-UP, and FAT-PM2.5-DN, whose transcriptional regulation profile in adipocytes was statistically similar by dietary intake and HFD and exposure to PM2.5 in mice; suggesting a mechanistic interaction between both factors. However, HFD-exposed murines developed moderate metabolically abnormal obesity, and PM2.5-exposed murines developed severe abnormal metabolism without obesity. Therefore, in Rothman's terms, it is concluded that HFD is a sufficient cause of the development of obesity, and PM2.5 is a component cause of severe abnormal metabolism of obesity. These signatures would be integrated into a systemic biological process that would induce transcriptional regulation in trans, activating obesogenic biological pathways, restricting lipid mobilization pathways, decreasing adaptive thermogenesis and angiogenesis, and altering vascular tone thus inducing a severe metabolically abnormal obesity.

5.
J. pediatr. (Rio J.) ; 100(supl.1): S48-S56, Mar.-Apr. 2024. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1558343

RESUMO

Abstract Objective To present the different aspects that may be involved in the genesis and maintenance of obesity in children and adolescents. Data source Narrative review of articles published in the PubMed, Scielo, Lilacs, Scopus and Google Scholar databases, using the search terms: overweight, obesity, pre-conception, prenatal, infants, schoolchildren, children, and adolescents. The search was conducted in studies written in Portuguese, English and Spanish, including narrative, integrative or systematic reviews, meta-analyses, cross-sectional, case-control and cohort studies, published between 2003 and 2023. Data synthesis A total of 598 studies were initially screened and 60 of them, which showed the main biopsychosocial aspects related to greater risks of excessive adiposity in the pediatric age, were included in the review. The data were presented taking into account the incidence of risk factors and their consequences in six periods: pre-conception, pre-natal, infant, preschool, school age, and adolescence. Conclusions The causal factors described in the scientific literature that have been shown to be related to obesity in childhood and adolescence are presented.

6.
Rev. Fac. Med. Hum ; 24(1): 42-50, ene.-mar. 2024. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1565131

RESUMO

RESUMEN Introducción: Las reacciones adversas a medicamentos (RAM) son manifestaciones clínicas o de laboratorio no deseadas que se relacionan con el consumo de medicamentos. Las RAM se asocian con un riesgo significativo de morbimortalidad e ingresos hospitalarios. Los antipsicóticos poseen una reducida ventana terapéutica y se han relacionado con la manifestación de una diversidad de RAM. Objetivo: Evaluar el patrón de las RAM debido a fármacos antipsicóticos, detectadas en pacientes atendidos en el Instituto Nacional de Psiquiatría Ramón de la Fuente Muñiz entre diciembre de 2021 y mayo de 2022. Métodos: Estudio observacional, descriptivo, prospectivo y transversal de una serie de casos. La gravedad, la severidad y la calidad de la información de la notificación de las RAM se definieron conforme a la NOM-220-SSA1-2016, instalación y operación de la farmacovigilancia, mientras que la causalidad se determinó mediante el algoritmo de Naranjo. Resultados: La incidencia de las RAM fue del 59% y se detectó una o más RAM en 52 de los 88 pacientes que estaban en tratamiento antipsicótico durante el periodo de estudio. El 45% de las RAM tuvo una causalidad probable y el 55%, posible; únicamente tres RAM se clasificaron como graves, debido a que prolongaron la estancia hospitalaria y pusieron en peligro la vida del paciente. Conclusiones: Las RAM de los sistemas gastrointestinal y endocrino fueron las más incidentes, y la hiperprolactinemia fue la más frecuente. La olanzapina y clozapina fueron los medicamentos que más RAM provocaron. Se recomienda fomentar la cultura de notificación y seguimiento de RAM causadas por fármacos antipsicóticos.


ABSTRACT Introduction: Adverse Drug Reactions (ADR) are unwanted clinical or laboratory manifestations that are related to drug use. ADR are common and are associated with significant risk of morbidity, mortality and hospital admissions. Antipsychotics have a reduced therapeutic window, and have been related to the manifestation of a variety of ADR. Objetive: To evaluate the pattern of ADRs due to antipsychotic drugs detected in patients treated at the Ramón de la Fuente Muñiz National Institute of Psychiatry between December 2021 and May 2022. Methods: Observational, descriptive, prospective and cross-sectional study of a series of cases. The seriousness, severity, and quality of the information in the notification of the ADR were defined in accordance with NOM-220-SSA1-2016, Installation and Operation of Pharmacovigilance, while causality was determined using the Naranjo algorithm. Results: The incidence of ADRs was 59%, with one or more ADR detected in 52 of the 88 patients who were receiving antipsychotic treatment during the study period. Forty-five percent of the ADR had probable causality and 55% possible; only three ADR were classified as serious as they prolonged the hospital stay and endangered the patient's life. Conclusions: The ADR of the gastrointestinal and endocrine systems were the most incidental, with hyperprolactinemia being the most frequent. Olanzapine and clozapine were the medications that caused the most ADR. It is recommended to promote the culture of notification and follow-up of ADR caused by antipsychotic drugs.

7.
J Pediatr (Rio J) ; 100 Suppl 1: S48-S56, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37918812

RESUMO

OBJECTIVE: To present the different aspects that may be involved in the genesis and maintenance of obesity in children and adolescents. DATA SOURCE: Narrative review of articles published in the PubMed, Scielo, Lilacs, Scopus and Google Scholar databases, using the search terms: overweight, obesity, pre-conception, prenatal, infants, schoolchildren, children, and adolescents. The search was conducted in studies written in Portuguese, English and Spanish, including narrative, integrative or systematic reviews, meta-analyses, cross-sectional, case-control and cohort studies, published between 2003 and 2023. DATA SYNTHESIS: A total of 598 studies were initially screened and 60 of them, which showed the main biopsychosocial aspects related to greater risks of excessive adiposity in the pediatric age, were included in the review. The data were presented taking into account the incidence of risk factors and their consequences in six periods: pre-conception, pre-natal, infant, preschool, school age, and adolescence. CONCLUSIONS: The causal factors described in the scientific literature that have been shown to be related to obesity in childhood and adolescence are presented.


Assuntos
Obesidade Infantil , Adolescente , Criança , Pré-Escolar , Humanos , Lactente , Adiposidade , Estudos Transversais , Sobrepeso/epidemiologia , Obesidade Infantil/epidemiologia , Obesidade Infantil/etiologia , Fatores de Risco , Recém-Nascido , Literatura de Revisão como Assunto , Metanálise como Assunto
8.
Rev. bras. saúde ocup ; 49: e8, 2024.
Artigo em Português | LILACS | ID: biblio-1550782

RESUMO

Resumo A esfera das perícias comumente reduz a questão do estabelecimento do nexo de causalidade entre trabalho e saúde/doença apenas ao binômio trabalho/vida pessoal. Partindo dos pressupostos dos campos Saúde do Trabalhador (ST) e Saúde Mental Relacionada ao Trabalho (SMRT), este ensaio visa problematizar o resultado da questão, que reside na existência de dificuldades enfrentadas por trabalhadores na obtenção do nexo causal entre seus agravos/adoecimentos, cuja causalidade mais complexa se explica a partir de várias mediações pouco consideradas nos atos periciais circunscritos apenas às anamneses clínicas de cunho biomédicas pautadas nos pressupostos da Medicina do Trabalho, Higiene e Saúde Ocupacional. As formas de superação à ideia de causa-efeito passam pelo entendimento de que o processo de adoecimento é social e histórico e de que é preciso buscar mediações entre trabalho e adoecimento para elucidar sintomatologias singulares a partir da experiência do desgaste coletivo. Tal averiguação deve, ao mesmo tempo, problematizar os próprios processos de trabalho dos atores sociais envolvidos nas investigações periciais e partir das prioridades definidas pelos próprios trabalhadores que atuam como sujeitos da análise da nocividade do trabalho para a saúde.


Abstract Expert testimonies commonly reduce the establishment of causal links between work and health/illness solely to the dichotomy of work/personal life. Based on the assumptions from the fields of Workers Health and Work-Related Mental Health, this essay problematizes the results of this issue, namely the difficulties faced by workers in establishing the causal link between their ailments/illnesses, whose more complex causality is explained through several mediations that are often overlooked by the limited expert acts restricted only to clinical anamneses based on Occupational Medicine, Hygiene, and Occupational Health. Overcoming the idea of cause and effect involves understanding that the process of falling ill is social and historical, and requires exploring the mediations between work and illness to elucidate singular symptomatology based on the collective wear and tear experience. Such an investigation should simultaneously problematize the very work processes of the social actors involved in the expert investigations, starting from the priorities defined by the workers themselves who act as subjects in the analysis of work-related harm to health.


Assuntos
Saúde Mental , Saúde Ocupacional , Atenção à Saúde
9.
Rev. adm. pública (Online) ; 58(3): e20230149, 2024. tab, graf
Artigo em Inglês, Português | LILACS | ID: biblio-1565205

RESUMO

Abstract This paper examines the causal effect of the levels of democracy in countries on the levels of corruption. Research shows that the levels of corruption in countries decrease when they reach higher levels of democracy. However, most of the evidence has been obtained through correlational or regression studies that do not make clear the causal connection between the variables. The research applied a robust estimator (IPWRA) to a database of 161 countries with average data from 2010-2019, assessing a causality model within the counterfactual framework. The results indicate that a causal relationship does exist; that is, a higher level of democracy in the countries reduces the levels of corruption.


Resumo Este artigo examina o efeito causal dos níveis de democracia dos países sobre seus níveis de corrupção. As pesquisas mostram que os níveis de corrupção nos países diminuem quando atingem níveis mais altos de democracia. No entanto, a maior parte da evidência foi obtida através de estudos correlacionais ou de regressão que não esclarecem a conexão causal entre as variáveis. O presente estudo utilizou dados médios de 161 países correspondentes ao período de 2010-2019 para estimar um modelo de causalidade usando um estimador robusto (IPWRA), seguindo o referencial teórico da análise contrafactual. Os resultados indicam que existe uma relação causal, ou seja, maiores níveis de democracia nos países resultam em reduções nos níveis de corrupção.


Resumen Este artículo examina el efecto causal de los niveles de democracia de los países sobre sus niveles de corrupción. Las investigaciones muestran que los niveles de corrupción en los países disminuyen cuando alcanzan niveles más altos de democracia. Sin embargo, la mayor parte de la evidencia se ha obtenido a través de estudios correlacionales o de regresión que no aclaran la conexión causal entre las variables. El presente estudio utilizó datos promedio de 161 países correspondientes al período 2010-2019 para estimar un modelo de causalidad mediante un estimador robusto (IPWRA), siguiendo el marco teórico del análisis contrafactual. Los resultados indican que sí existe una relación causal, es decir, mayores niveles de democracia en los países producen reducciones en los niveles de corrupción.


Assuntos
Política , Causalidade , Democracia , Corrupção
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