The uniqueness of the human brain: a review.

The purpose of this review is to highlight the most important aspects of the anatomical and functional uniqueness of the human brain. For this, a comparison is made between our brains and those of our closest ancestors (chimpanzees and bonobos) and human ancestors. During human evolution, several changes occurred in the brain, such as an absolute increase in brain size and number of cortical neurons, in addition to a greater degree of functional lateralization and anatomical asymmetry. Also, the cortical cytoarchitecture became more diversified and there was an increase in the number of intracortical networks and networks extending from the cerebral cortex to subcortical structures, with more neural networks being invested in multisensory and sensory-motor-affective-cognitive integration. These changes permitted more complex, flexible and versatile cognitive abilities and social behavior, such as shared intentionality and symbolic articulated language, which, in turn, made possible the formation of larger social groups and cumulative cultural evolution that are characteristic of our species.

Esta revisão se propõe a relatar os aspectos mais importantes da singularidade anatômica e funcional do cérebro humano. Para isso, faz-se uma comparação entre o nosso cérebro e os de nossos parentes evolutivos mais próximos (chimpanzés e bonobos) e os ancestrais humanos. Durante a evolução humana ocorreu aumento absoluto do tamanho do cérebro e do número de neurônios corticais cerebrais, maior grau de lateralização funcional e assimetria anatômica cerebral, citoarquitetura cortical mais diversificada e aumento das redes neurais intracorticais e do córtex cerebral para as estruturas subcorticais acompanhada de mudança em direção ao investimento de redes neurais na integração multissensorial e sensório-motora-afetiva-cognitiva. Essas mudanças possibilitaram capacidades cognitivas e comportamentos sociais complexos, flexíveis e versáteis, destacando-se a intencionalidade compartilhada e a linguagem articulada simbólica, que permitiram a formação de grupos sociais maiores e a evolução cultural cumulativa característica de nossa espécie.

"Estrutura da Celula Nervoza", by Bruno Lobo and Gaspar Vianna (1908): a pioneering work on Brazilian Neuroscience.

Currently, the scientific production in Neuroscience in Brazil is very rich, but, historically, it has been scarce at first. The aim of this study is to present the work "Estrutura da Celula Nervoza", by Bruno Lobo and Gaspar Vianna (1908), as a pioneering work for Brazilian science.

The remarkable pioneering contribution of Gaspar Vianna to the study of the neuropathology of Chagas disease / A notável contribuição pioneira de Gaspar Vianna para o estudo da neuropatologia da doença de Chagas

ABSTRACT Gaspar Vianna is considered one of the great names in Medicine and Science in Brazil. Yet, little prominence has been given to his studies in Neuropathology. He was the first to describe, in 1911, the histopathology and pathogenesis of chagasic encephalitis in the acute phase of Chagas disease, as well as the intracellular life cycle of Trypanosoma cruzi. Over 100 years have elapsed and Gaspar Vianna's pioneering study remains an example of a meticulous and still up-to-date description of central nervous system involvement in the acute phase of Chagas disease.

RESUMO Gaspar Vianna é considerado um dos grandes nomes da Medicina e da Ciência no Brasil. Contudo, pouco destaque tem sido dado aos seus estudos em Neuropatologia. Ele foi o primeiro a descrever a histopatologia e a patogênese da encefalite chagásica na fase aguda da doença de Chagas, bem como o ciclo evolutivo intracelular do Trypanosoma cruzi, em 1911. Passados mais de 100 anos, o estudo pioneiro de Gaspar Vianna permanece como exemplo de descrição minuciosa e ainda atual do envolvimento do sistema nervoso central na fase aguda da doença de Chagas.

[The Nobel Prize database as an indicator of the internationalization of Brazilian science from 1901 to 1966]. / O banco de dados do Prêmio Nobel como indicador da internacionalização da ciência brasileira entre 1901 e 1966.

Working with the Nobel Prize database, covering 1901-1966, the article examines the analytical potential of the participation of Brazilians both as nominees for the world's most prestigious award in science, the Nobel Prize, and also as invited nominators. Of the 18 Brazilians nominated for the Nobel, nine were in the category Peace, four in Literature, four in Physiology or Medicine, and one in Physics. The article comments on the nominations of Brazilian scientists in the categories of Physics and Physiology or Medicine, as well as on nominations by Brazilian nominators in these same two categories. It also discusses the process of science evaluation, based on the information attained through analysis of these data on the Nobel award.

O trabalho explora o potencial de análise da participação de brasileiros indicados à mais prestigiada premiação mundial em ciência, o Nobel, bem como dos brasileiros convidados para indicar candidatos à premiação, com base no banco de dados do Prêmio Nobel, cobrindo o período 1901-1966. Dezoito brasileiros foram indicados ao Prêmio Nobel, dos quais nove ao da Paz, quatro ao de Literatura, quatro ao de Fisiologia ou Medicina e um ao de Física. São comentadas as indicações dos cientistas brasileiros à premiação de Física e de Fisiologia ou Medicina e as dos nomeadores brasileiros nestas duas últimas categorias. Discute-se o processo de avaliação em ciência com base no conhecimento obtido após análise dos dados referentes à premiação do Nobel.

O banco de dados do Prêmio Nobel como indicador da internacionalização da ciência brasileira entre 1901 e 1966 / The Nobel Prize database as an indicator of the internationalization of Brazilian science from 1901 to 1966

Resumo O trabalho explora o potencial de análise da participação de brasileiros indicados à mais prestigiada premiação mundial em ciência, o Nobel, bem como dos brasileiros convidados para indicar candidatos à premiação, com base no banco de dados do Prêmio Nobel, cobrindo o período 1901-1966. Dezoito brasileiros foram indicados ao Prêmio Nobel, dos quais nove ao da Paz, quatro ao de Literatura, quatro ao de Fisiologia ou Medicina e um ao de Física. São comentadas as indicações dos cientistas brasileiros à premiação de Física e de Fisiologia ou Medicina e as dos nomeadores brasileiros nestas duas últimas categorias. Discute-se o processo de avaliação em ciência com base no conhecimento obtido após análise dos dados referentes à premiação do Nobel.

Abstract Working with the Nobel Prize database, covering 1901-1966, the article examines the analytical potential of the participation of Brazilians both as nominees for the world's most prestigious award in science, the Nobel Prize, and also as invited nominators. Of the 18 Brazilians nominated for the Nobel, nine were in the category Peace, four in Literature, four in Physiology or Medicine, and one in Physics. The article comments on the nominations of Brazilian scientists in the categories of Physics and Physiology or Medicine, as well as on nominations by Brazilian nominators in these same two categories. It also discusses the process of science evaluation, based on the information attained through analysis of these data on the Nobel award.

The remarkable pioneering contribution of Gaspar Vianna to the study of the neuropathology of Chagas disease.

Gaspar Vianna is considered one of the great names in Medicine and Science in Brazil. Yet, little prominence has been given to his studies in Neuropathology. He was the first to describe, in 1911, the histopathology and pathogenesis of chagasic encephalitis in the acute phase of Chagas disease, as well as the intracellular life cycle of Trypanosoma cruzi. Over 100 years have elapsed and Gaspar Vianna's pioneering study remains an example of a meticulous and still up-to-date description of central nervous system involvement in the acute phase of Chagas disease.

Cytoarchitecture of nitrergic neurons in the human striatum and subthalamic nucleus.

BACKGROUND: Nitric oxide (NO) is a gaseous molecule that modulates several physiological processes, including signal transmission in the central nervous system. There is evidence supporting NO as a major neurotransmitter involved in motor and emotion/behavior control. We investigated the distribution and morphology of nitrergic neurons in the two main input structures of the basal ganglia of human brain: the striatum and subthalamic nucleus. METHODS: We studied samples of striatum (caudate and putamen) and subthalamic nucleus of 20 human brains from subjects without neurological/psychiatric diseases. The tissues were stained by histochemistry for nicotinamide adenine dinucleotide phosphate diaphorase activity and by immunohistochemistry for neuronal NO synthase (nNOS). Subsequently, we analyzed the nitrergic neuronal profile and its morphometric parameters. RESULTS: Our data corroborate that approximately 2% of neurons in striatum express nNOS and these exhibited morphology characteristic of interneurons. Posterior regions of the striatum have a higher nitrergic neuronal profile than anterior regions of this nucleus suggesting an anteroposterior gradient of nitrergic neurons. Posterior limbic-associated areas of the striatum have a higher nitrergic neuronal profile compared to other functional subdivisions. Also, approximately 90% of neurons in the subthalamic nucleus express nNOS. CONCLUSIONS: A remarkable presence of nitrergic neurons in the human striatum and subthalamic nucleus suggests that NO may play a critical role in the physiology of these nuclei.

Effects of aging on nitrergic neurons in human striatum and subthalamic nucleus.

Nitric oxide (NO) is a major neurotransmitter associated with motor control in basal ganglia. Movement disorders, as essential tremor and Parkinson's disease, are more prevalent on aged individuals. We investigated the effects of aging on neuronal density and diameter/area of nitrergic neurons in samples of striatum (caudate and putamen) and subthalamic nucleus of 20 human brains from normal subjects, stained by histochemistry for NADPH-diaphorase and immunohistochemistry for neuronal NO synthase. Our data showed aging does not modify the neuronal density and size of nitrergic neurons in striatum and subthalamic nucleus. These findings suggest a lack of association between aging and morphologic changes on nitrergic neurons.

Effects of aging on nitrergic neurons in human striatum and subthalamic nucleus / Efeitos do envelhecimento sobre os neurônios nitrérgicos no estriado e núcleo subtalâmico humano

Nitric oxide (NO) is a major neurotransmitter associated with motor control in basal ganglia. Movement disorders, as essential tremor and Parkinson’s disease, are more prevalent on aged individuals. We investigated the effects of aging on neuronal density and diameter/area of nitrergic neurons in samples of striatum (caudate and putamen) and subthalamic nucleus of 20 human brains from normal subjects, stained by histochemistry for NADPH-diaphorase and immunohistochemistry for neuronal NO synthase. Our data showed aging does not modify the neuronal density and size of nitrergic neurons in striatum and subthalamic nucleus. These findings suggest a lack of association between aging and morphologic changes on nitrergic neurons.

O óxido nítrico (NO) é um importante neurotransmissor associado ao controle motor nos núcleos da base. Os distúrbios de movimento, como tremor essencial e a doença de Parkinson, são mais prevalentes em indivíduos idosos. Nós investigamos os efeitos do envelhecimento sobre a densidade neuronal e diâmetro/área dos neurônios nitrérgicos em amostras de estriado (caudado e putâmen) e núcleo subtalâmico de 20 encéfalos humanos de indivíduos normais, corados pela técnica histoquímica da NADPH-diaforase e imunohistoquímica para a sintase do NO neuronal. Nossos resultados mostraram que o envelhecimento não modifica a densidade neuronal e as dimensões dos neurônios nitrérgicos no estriado e núcleo subtalâmico. Estes achados sugerem uma falta de associação entre envelhecimento e mudanças morfológicas nos neurônios nitrérgicos.

Influence of external factors on the preservation of human nervous tissue for histological studies: review article / Influência dos fatores externos sobre a preservação do tecido nervoso humano nos estudos histológicos: artigo de revisão

Neuropathological studies are crucial for the new knowledge on pathophysiology and treatment of neurodegenerative diseases, such as Alzheimer's disease and Parkinson's disease. The postmortem brain tissue processing method directly impacts on both the appropriate integrity and the biomolecules detection by different histological and molecular biology techniques. In this review we will discuss topics on the influence of some external factors on the preservation of the brain tissue for histological studies (histochemistry and immunohistochemistry), such as factors either prior or after the death, and the chosen method for the preservation of nervous tissue. By means of a specific example, we propose a strict record of various conditions involved in the method of preservation of nervous tissue, and its correlation with variables that measure the quality of the histological sample as markers of preservation of biological material for further studies.

Os estudos neuropatológicos são fundamentais para novas descobertas sobre a fisiopatologia e o tratamento de doenças neurodegenerativas, como a doença de Alzheimer e a doença de Parkinson. O modo como o encéfalo pós-morte é processado influencia diretamente na adequada integridade e na detecção de biomoléculas por diferentes técnicas histológicas e de biologia molecular. Nesta revisão, abordaremos tópicos sobre a influência de determinados fatores externos sobre a preservação do encéfalo para estudos histológicos (histoquímica e imuno-histoquímica), como as condições anteriores e posteriores ao óbito, e o método escolhido de conservação do tecido nervoso. Por meio de um exemplo específico, propomos um rigoroso registro das diversas condições envolvidas no processo de preservação do tecido nervoso e sua correlação com variáveis que avaliam a qualidade da amostra histológica, como marcadores da preservação do material biológico para estudos posteriores..

Open-ring enhancement in pseudotumoral multiple sclerosis: important radiological aspect.

Introduction. Observation of open-ring enhancement in magnetic resonance imaging (MRI) is considered a specificity marker for diagnosing pseudotumoral multiple sclerosis (MS). This finding is of great value in the differential diagnosis of tumefactive lesions. Case Report. We describe a 55-year-old white woman, with previous history of ovarian cancer and recent history of fatigue and bilateral retroorbital pain. Important bilateral visual impairment evolved over one month. Physical examination detected the presence of right homonymous hemianopia. Cranial MRI showed an expanding lesion with open-ring enhancement. Given the range of diagnostic possibilities, a stereotactic biopsy was performed, and histopathological examination was consistent with an active demyelinating disease. The patient was treated with 1 g of methylprednisolone and symptoms improved following a significant reduction in the lesion. Conclusions. We highlight the MRI results suggestive of pseudotumoral MS, especially open-ring enhancement, which is an important radiologic aspect to diagnosis and can assist in avoiding unnecessary biopsies.

Pathology of CNS parasitic infections.

Parasitic infections of the central nervous system (CNS) include two broad categories of infectious organisms: single-celled protozoa and multicellular metazoa. The protozoal infections include malaria, American trypanosomiasis, human African trypanosomiasis, toxoplasmosis, amebiasis, microsporidiasis, and leishmaniasis. The metazoal infections are grouped into flatworms, which include trematoda and cestoda, and roundworms or nematoda. Trematoda infections include schistosomiasis and paragonimiasis. Cestoda infections include cysticercosis, coenurosis, hydatidosis, and sparganosis. Nematoda infections include gnathostomiasis, angiostrongyliasis, toxocariasis, strongyloidiasis, filariasis, baylisascariasis, dracunculiasis, micronemiasis, and lagochilascariasis. The most common route of CNS invasion is through the blood. In some cases, the parasite invades the olfactory neuroepithelium in the nasal mucosa and penetrates the brain via the subarachnoid space or reaches the CNS through neural foramina of the skull base around the cranial nerves or vessels. The neuropathological changes vary greatly, depending on the type and size of the parasite, geographical strain variations in parasitic virulence, immune evasion by the parasite, and differences in host immune response. Congestion of the leptomeninges, cerebral edema, hemorrhage, thrombosis, vasculitis, necrosis, calcification, abscesses, meningeal and perivascular polymorphonuclear and mononuclear inflammatory infiltrate, microglial nodules, gliosis, granulomas, and fibrosis can be found affecting isolated or multiple regions of the CNS, or even diffusely spread. Some infections may be present as an expanding mass lesion. The parasites can be identified by conventional histology, immunohistochemistry, in situ hybridization, and PCR.