ABSTRACT
The human neocortex has a cytoarchitecture composed of six layers with an intrinsic organization that relates to afferent and efferent pathways for a high functional specialization. Various histological, neurochemical, and connectional techniques have been used to study these cortical layers. Here, we explore the additional possibilities of swift ion beam and synchrotron radiation techniques to distinguish cellular layers based on the elemental distributions and areal density pattern in the human neocortex. Temporal cortex samples were obtained from two neurologically normal adult men (postmortem interval: 6-12 h). A cortical area of 500 × 500 µm2 was scanned by a 3 MeV proton beam for elemental composition and areal density measurements using particle induced x-ray emission (PIXE) and scanning transmission ion microscopy (STIM), respectively. Zinc showed higher values in cortical layers II and V, which needs a critical discussion. Furthermore, the areal density decreased in regions with a higher density of pyramidal neurons in layers III and V. Scanning transmission X-ray microscopy (STXM) revealed the cellular density with higher lateral resolution than STIM, but not enough to distinguish each cortical lamination border. Our data describe the practical results of these approaches employing both X-ray and ion-beam based techniques for the human cerebral cortex and its heterogeneous layers. These results add to the potential approaches and knowledge of the human neocortical gray matter in normal tissue to develop improvements and address further studies on pathological conditions.
Subject(s)
Neocortex , Male , Adult , Humans , Microscopy , X-Rays , Magnetic Resonance Imaging , Cell CountABSTRACT
The concentration and distribution of Mg, P, Cl, K, Cu and Zn in the dorsal hippocampus CA1 region of rat brains were studied during memory consolidation and reconsolidation processes stimulated with inhibitory avoidance (IA) tests. Experimental rats were divided into four groups: i) group not submitted to inhibitory avoidance task (IA-N); ii) group submitted to inhibitory avoidance training session (IA-Y); iii) group submitted to inhibitory avoidance reactivation session but did not step down from the platform (IAR-N); and iv) group submitted to avoidance reactivation session and stepped down from the platform (IAR-Y). Elemental concentration and distribution in the CA1 hippocampus region were obtained through the Particle-Induced X-ray Emission (PIXE) technique. The results indicate that the concentration of Mg, P, Cl, K and Cu increased during memory consolidation. During the memory reconsolidation process, the concentrations of Mg, P, Cl and K increased, while Cu and Zn had no significant changes with respect to their basal condition. These results show that the major part of these elements may be engaged in memory consolidation could be also participating in memory reconsolidation. For all elements, the general trend related to their concentration did not change during reconsolidation regardless the presence of a novelty event, i.e. stepping down from the platform.
Subject(s)
Brain Chemistry , CA1 Region, Hippocampal/chemistry , CA1 Region, Hippocampal/physiology , Memory Consolidation/physiology , Animals , Chlorine/analysis , Chlorine/metabolism , Copper/analysis , Copper/metabolism , Magnesium/analysis , Magnesium/metabolism , Male , Phosphorus/analysis , Phosphorus/metabolism , Rats , Rats, Wistar , Zinc/analysis , Zinc/metabolismABSTRACT
The chronic use of agrotoxics in rural regions of Rio Grande do Sul State (RS) has been tentatively associated to a possible increase in the incidence of cancer in rural areas. A time-trend ecological study was performed in the micro region of Ijuí County (MI), in RS and Brazil, with data of the 1979 to 2003 period. Data was collected from the Mortality Information System, Brazilian Ministry of Health (DATASUS), to evaluate the cancer mortality rate, standardized by gender and age - corrected mortality ratios. Linear regression for mortality time-trend analysis and multiple regressions for mortality differences among three regions were calculated. The highest average mortality rate in men and also women were observed in RS and MI and they were significantly higher (p<0,001) than the one for Brazil. When the model was adjusted for three regions the upward trend on mortality remained the same. This data suggests that the relation between chronic use of agrotoxics and cancer cannot be denied and should be further investigated.
Subject(s)
Agrochemicals/toxicity , Neoplasms/chemically induced , Neoplasms/mortality , Adult , Aged , Brazil , Female , Humans , Male , Middle Aged , Young AdultABSTRACT
O uso crônico de agrotóxicos em regiões rurais no Estado do Rio Grande do Sul (RS) tem sido tentativamente relacionado a um possível aumento na incidência de câncer nos trabalhadores rurais. Foi realizado um estudo ecológico de série temporal (1979 a 2003) na microrregião (MI) de Ijuí, no Estado do Rio Grande do Sul e no Brasil, com dados anuais do Sistema do Departamento de Estatística do Sistema Único de Saúde (DATASUS), para avaliar o comportamento do coeficiente de mortalidade por câncer, padronizado por idade e sexo. Utilizou-se um modelo de regressão linear simples e múltipla para estimar, respectivamente, as taxas de mortalidade e as diferenças entre as três regiões estudadas. A MI e o RS apresentam maior taxa média de mortalidade tanto em homens quanto em mulheres, sendo significativamente diferentes das observadas para o Brasil como um todo (p<0,001). Quando o modelo foi ajustado para as três regiões, a tendência de aumento da taxa de mortalidade permanece. Esses dados sugerem que a relação entre uso crônico de agrotóxicos e câncer não pode ser rejeitada e que deve ser melhor estudada.
The chronic use of agrotoxics in rural regions of Rio Grande do Sul State (RS) has been tentatively associated to a possible increase in the incidence of cancer in rural areas. A time-trend ecological study was performed in the micro region of Ijuí County (MI), in RS and Brazil, with data of the 1979 to 2003 period. Data was collected from the Mortality Information System, Brazilian Ministry of Health (DATASUS), to evaluate the cancer mortality rate, standardized by gender and age - corrected mortality ratios. Linear regression for mortality time-trend analysis and multiple regressions for mortality differences among three regions were calculated. The highest average mortality rate in men and also women were observed in RS and MI and they were significantly higher (p<0,001) than the one for Brazil. When the model was adjusted for three regions the upward trend on mortality remained the same. This data suggests that the relation between chronic use of agrotoxics and cancer cannot be denied and should be further investigated.
Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Agrochemicals/toxicity , Neoplasms/chemically induced , Neoplasms/mortality , Brazil , Young AdultABSTRACT
O câncer de mama é apontado como o tipo de câncer mais prevalente no mundo. No Brasil, as taxas de mortalidade por câncer de mama continuam elevadas, observando-se diferenças inter-regionais. Foi realizado um estudo ecológico de série temporal (1980-2002) na Região Sul, com dados anuais do Departamento de Informação e Informática do SUS (DATASUS), para avaliar o comportamento do coeficiente de mortalidade por câncer de mama, padronizado por idade. Utilizou-se regressão linear simples e múltipla para estimar as taxas de mortalidade e as diferenças entre os três Estados. O Rio Grande do Sul parte de um patamar mais elevado e apresenta maior taxa média de mortalidade (14,45), sendo significativamente diferente (p < 0,001) quando comparado com Santa Catarina (8,93) e Paraná (9,95). Observou-se um aumento anual de 0,47 óbito na taxa de mortalidade por câncer de mama, independente do Estado. Conclui-se que há uma tendência similar de aumento da mortalidade por câncer de mama nos três Estados da Região Sul, com índices significativamente maiores no Rio Grande do Sul, enfatizando-se a importância da identificação dos fatores relacionados a esse quadro alarmante e o estabelecimento de medidas efetivas a fim de reverter esses números.
Breast cancer is the most prevalent form of cancer in the world. Breast cancer mortality rates are high in Brazil and show striking variations between geographic regions. A time-trend ecological study was performed in Southern Brazil from 1980 to 2002. Data were collected from the Mortality Information System (Ministry of Health) to assess age-standardized mortality rates. Linear regression for mortality time-trend analysis and multiple regression for mortality differences among three States were calculated. The highest mean mortality rate (14.45) was observed in Rio Grande do Sul, significantly greater (p < 0.001) than in Santa Catarina (8.93) and Paraná (9.95). An annual increase of 0.47 in the mortality rate was observed in the three States of Southern Brazil. According to these results, the South of Brazil and especially the State of Rio Grande do Sul showed a significant upward trend in breast cancer mortality. Continued efforts are needed to help explain these numbers and reverse the present situation.
