Application of brain organoids in environmental toxicology / 环境与职业医学

Since the 19th century, the emergence of model systems has helped researchers further understand cellular signaling pathways, identify potential drug targets, and conduct environmental toxicological studies. Exogenous chemicals, such as pollutants, drugs, and industrial chemicals, may affect brain biological processes and functions and eventually lead to neurological diseases. However, the brain is a complex and well-organized human organ, which is fundamentally different from any existing model system. Animal models may not be able to completely simulate the human brain in testing the neurotoxicity of environmental pollutants due to species differences. Human brain organoids, generated from human pluripotent stem cells, are emerging model systems for neurotoxicological research in line with the real situation of human body at the level of genome, transcriptome, and metabolome, and provide an effective platform for testing neurotoxicity of environmental toxins. We reviewed the latest development of brain organoids technology and its application in the evaluation of environmental neurotoxins, and provided new insights into the application of brain organoids in environmental neurotoxicology.

Abordagem inicial no atendimento ambulatorial em distúrbios neurotoxicológicos: parte III - solventes orgânicos / Initial approach to outpatient treatment of neurotoxicological disorders: Part III – organic solvents

Introdução: Milhões de pessoas são expostas diariamente aos solventes. Inúmeros solventes podem causar intoxicação aguda. Menos clara é a associação da exposição crônica e em baixas doses poder produzir alteração neurológica. Diversas atividades ocupacionais estão envolvidas com a sua exposição. Condição bastante diferente é o seu uso inadvertido com intuito alucinógeno. Método: Trata-se de revisão atualizada da literatura a partir de pesquisa na base de dados MEDLINE e LILACS. Também utilizou-se livros e documentos publicados em formato eletrônico.Discussão: Distúrbios neuromusculares, distúrbios do movimento, alterações cognitivo-comportamentais e neurofisiológicas têm sido relacionados a inúmeros agentes tóxicos nos últimos anos. A proposta deste artigo é revisar os principais distúrbios neurológicos associados à exposição crônica por solventes orgânicos. A fim de facilitar a abordagem inicial no atendimento ambulatorial aos distúrbios neurotoxicológicos foram confeccionadas tabelas descrevendo os principais agentes tóxicos, as fontes de exposição envolvidas e suas principais manifestações neurológicas. Conclusão: Tolueno, bissulfeto de carbono e n-Hexano são alguns solventes envolvidos nos distúrbios neurotoxicológicos, Contudo, fica evidente nesta revisão que são necessários novos estudos a fim de determinar a real associação destes e outros solventes nos distúrbios crônicos do sistema nervoso central e periférico.

Introduction: Millions of peoples are exposed to solvents every day. Most solvents cause acute intoxication. Less evident is the association of chronic exposure and in low doses in producing neurological disorders. Innumerable occupational activities are involved in the exposure to solvents. Their inadvertent use with hallucinogenous intention is an entirely different condition. Method: The method consists of an updated review of the literature based on research in the MEDLINE and LILACS databases, as well as books and documents published online. Discussion: Neuromuscular disorders, movement disorders, cognitive-behavioral and neurophysiological changes have been attributed to innumerable toxic agents in recent years. This article proposes to review the main neurological disorders associated with chronic exposure to organic solvents. To facilitate the initial approach to treatment of neurotoxicological disorders of outpatient, tables were devised to describe the main toxic agents, the sources of exposure involved and their main neurological manifestations. Conclusions: Toluene, carbon bisulfate and n-hexane are some of the solvents involved in neurotoxicological disorders. However, this review reveals the need for new studies to determine the real association of these and other solvents in chronic disorders of the central and peripheral nervous systems.

Abordagem inicial no atendimento ambulatorial em distúrbiosneurotoxicológicos. Parte II - agrotóxicos / Initial approach to outpatient treatment of neurotoxicological disorders. Part II – pesticides

Introdução: A venda de agrotóxicos no Brasil representa 86% do mercado consumidor da América Latina, com um faturamento anual que chega a US$ 7 bilhões. O desconhecimento e a falta de percepção dos riscos inerentes a utilização dessas substâncias é constatada com frequência aumentando as chances de intoxicação por tais agentes. Métodos: Trata-se de revisão atualizada da literatura a partir de pesquisa na base de dados MEDLINE e LILACS. Também utilizaram-se livros e documentos publicados em formato eletrônico. Resultados e discussão: Distúrbios neuromusculares, distúrbios do movimento, alterações cognitivo-comportamentais e neurofisiológicas têm sido relacionados a inúmeros agentes tóxicos nos últimos anos. A proposta deste artigo é revisar os principais distúrbios neurológicos associados à exposição crônica por agrotóxicos. A fim de facilitar a abordagem inicial no atendimento ambulatorial aos distúrbios neurotoxicológicos foram confeccionadas tabelas descrevendo os principais agentes tóxicos, as fontes de exposição envolvidas e suas principais manifestações neurológicas. Conclusão: Inseticidas, herbicidas, fungicidas e fumigantes são alguns agrotóxicos envolvidos nos distúrbios neurotoxicológicos. Contudo, fica evidente nesta revisão que são necessários novos estudos a fim de determinar a real associação destes e outros agrotóxicos nos distúrbios crônicos do sistema nervoso central e periférico.

Introduction: The sale of pesticides in Brazil represents 86% of the Latin American consumer market, with annual revenues reachingup to US$ 7 billion. Lack of knowledge and unawareness of the risks inherent to the use of these substances is frequently found, increasingthe possibility of intoxication by these agents. Methods: The method consists of an updated review of the literature based on research in theMEDLINE and LILACS databases, as well as books and documents published online. Results and discussion: Neuromusculardisorders, movement disorders, cognitive-behavioral and neurophysiologic alterations have been attributed to innumerable toxic agents in recentyears. This article proposes to review the main neurological disorders associated with chronic exposure to pesticides. To make easy the initialapproach to outpatient treatment of neurotoxicological disorders, tables were devised to describe the main toxic agents, the sources of exposureinvolved and their main neurological manifestations. Conclusion: Insecticides, herbicides, fungicides and fumigants are some of the pesticides involved in neurotoxicological disorders. However, this review reveals the need for new studies to determine the real association of these and other pesticides in chronic disorders of the central and peripheral nervous systems.

Abordagem inicial no atendimento ambulatorial em distúrbios neurotoxicológicos. Parte I - metais / Initial approach to outpatient treatment of neurotoxicological disorders. Part I – metals

Introdução: A toxicologia é uma ciência que envolve inúmeros sistemas necessitando de uma equipe multiprofissional e interdisciplinar. A indistinção clínica entre as doenças ocupacionais e não ocupacionais dificulta o seu diagnóstico. Nesse contexto, a neurotoxicologia ocupacional e ambiental estuda os distúrbios do sistema nervoso central (SNC) e periférico (SNP) decorrente da intoxicação dos mais variados agentes. Método: Trata-se de revisão atualizada da literatura a partir de pesquisa na base de dados MEDLINE e LILACS. Também utilizou-se livros e documentos publicados em formato eletrônico. Resultados e Discussão: Distúrbios neuromusculares, distúrbios do movimento, doença do neurônio motor, alterações cognitivocomportamentais e neurofisiológicas têm sido relacionados a inúmeros agentes tóxicos nos últimos anos. A proposta deste artigo é revisar os principais distúrbios neurológicos associados à exposição crônica por metais. A fim de facilitar a abordagem inicial no atendimento ambulatorial aos distúrbios neurotoxicológicos foram confeccionadas tabelas descrevendo os principais agentes tóxicos, as fontes de exposição envolvidas e suasprincipais manifestações neurológicas. Conclusão: Arsênio, chumbo, mercúrio, manganês, cádmio e estanho são alguns metais envolvidos nos distúrbios neurotoxicológicos. Contudo, fica evidente nesta revisão que são necessários novos estudos a fim de determinar a real associação destes e outros metais nos distúrbios crônicos do sistema nervoso central e periférico.

Introduction: Toxicology is a science that involves innumerable systems and requires a multiprofessional and interdisciplinary team. The clinical indistinctiveness of occupational and non-occupational disorders makes their diagnosis difficult. In this context, occupational and environmental toxicology studies the disorders of the central nervous system (CNS) and the peripheral nervous system (PNS) resulting from intoxication by a wide variety of agents. Method: The method consists of an updated review of the literature based on research in the MEDLINE and LILACS databases, as well as books and documents published online. Results and Discussion: Neuromuscular disorders, movement disorders, motor neuron disease, cognitive-behavioral and neurophysiological alterations have been attributed to innumerable toxic agents in recent years. This article proposes to review the main neurological disorders associated with chronic exposure to metals. To facilitate the initial approach to outpatient treatment of neurotoxicological disorders, tables were devised to describe the main toxic agents, the sources of exposure involved and their main neurological manifestations. Conclusions: Arsenic, lead, mercury, manganese, cadmium and tin are some of the metals involved in neurotoxicological disorders. However, this review reveals the need for new studies to determine the real association of these and other metals in chronic disorders of the central and peripheral nervous systems.

Impairment of color spatial vision in chronic alcoholism measured by psychophysical methods

We used psychophysical tests to evaluate spatial vision in 15 subjects with a clinical history of chronic alcoholism by measuring luminance contrast sensitivity and color discrimination. The subjects were initially subjected to clinical inquiry and ophthalmological exam. Subjects then performed psychophysical tests to measure spatial contrast thresholds using sine wave gratings of different spatial frequencies and contrasts and chromatic discrimination thresholds using the Mollon-Reffin test. For the analysis, subjects were divided into three groups according to age and compared with age-matched controls. Ten subjects had some degree of color vision loss, which was quite severe in seven cases. All subjects had normal luminance contrast sensitivity. The results suggest that color vision changes related to chronic alcoholism can occur in the absence of impairment of spatial luminance contrast sensitivity and thus is an important aspect to be considered in the clinical evaluation of this condition.