Resumen Objetivo: estimar el número y el costo médico directo del accidente cerebrovascular y los eventos adversos en usuarios de warfarina por fibrilación auricular. Métodos: se utilizó la metodología del análisis de impacto presupuestario para estimar el número de casos y el costo de los eventos. Se calculó la población diana con base en información poblacional de Colombia, así como las tasas de uso de warfarina según el riesgo y la distribución del tiempo en rango terapéutico de la misma. Se estimaron los eventos con base en probabilidades reportadas, y los costos utilizados en el modelo fueron calculados con información de una cohorte de pacientes con accidente cerebrovascular que se lleva a cabo en la Fundación Cardiovascular de Colombia. Resultados: la población diana fue de 84 623 pacientes en 1 año. El costo total de los accidentes cerebrovasculares y los sangrados fue de $36 852 236 476 millones COP. El costo total de los accidentes cerebrovasculares fue $5 004 588 241 COP; el costo total de las hemorragias intracraneales fue $11 875 730 234 COP y el de las hemorragias gastrointestinales fue $19 246 023 614 COP. El sangrado retroperitoneal, la epistaxis y el sangrado del tracto urinario fueron $735 894 387COP. El análisis de sensibilidad mostró que un ajuste en 10% de los tiempos en rango terapéutico podría ahorrar $4 211 957 037 COP. Conclusiones: el costo del accidente cerebrovascular y de los eventos adversos por warfarina es grande. Sin embargo, un ajuste de los tiempos en rango terapéutico podría ahorrar costos, lo que significa vidas de pacientes.

Abstract Objective: The aim of this study is to estimate the number and direct medical cost of cerebrovascular accident (stroke) and the adverse events in patients on warfarin due to atrial fibrillation. Methods: A budget impact analysis methodology was used to estimate the number of cases and cost of the events. The target population was based on Colombian population information, as well as the rates of use of warfarin according to risk and the distribution of its therapeutic time range. The events were estimated base on reported probabilities, and the costs used in the model were calculated from a cohort of stroke patients that was performed in the Cardiovascular Foundation of Colombia. Results: The target population consisted of 84,623 patients in 1 year. The total cost the strokes and bleeding was €10,426,275.28 ($36 852 236 476 million COP (Note: 3,500 /3,000Colombian Pesos (COP) = 1 Euro approx). The total cost strokes was €1,415,903.61 ($5 004 588 241 COP). The total costs of intracranial and gastrointestinal bleeding was €3,359,894.66 ($11 875 730 234 COP) and €5,445,106.17 ($19 246 023 614 COP), respectively. Retroperitoneal bleeding, epistaxis (nosebleeds) and urinary tract bleeding was €208,200.05 ($735 894 387 COP). The sensitivity analysis showed that an adjustment of 10% in the therapeutic time ranges could save €1,191,651.52 ($4 211 957 037 COP). Conclusions: The cost of the cerebrovascular accident and the adverse effects due to warfarin is large. However, an adjustment in the therapeutic range times could save costs, which means patient lives.

Abstract Being well hydrated is related to an adequate state of health and well-being; however, what happens in those adult patients having some pathological conditions such as obesity, type 2 diabetes mellitus, high blood pressure, ischemic heart disease and heart failure, kidney diseases (renal failure, polycystic renal disease and renal lithiasis), chronic obstructive pulmonary disease, dyslipidemia, hyperuricemia, or in the elderly and in the perioperative period, where there is loss of health or a different need for hydration and require the use of non-alcoholic beverages in order to have a good state of hydration without altering the natural evolution of these conditions? Some key points and recommendations are: carbonation of beverages offers the benefit of increasing satiety and decreasing energy intake, which can contribute to weight loss; simple water is the best source of hydration in diabetic patients; however, other sources of hydration may be mineralized water, mineral water, milk (preferably non-fat), coffee and tea without sugar or non-caloric sweeteners or low-calorie, as well as any beverage containing them; in patients with renal lithiasis it is recommended to take 2.5 to 4 L of water per day; sports drinks can be consumed by hypertensive patients as long as they do not exceed the amount of sodium recommended by the World Health Organization. In conclusion, hydration plays an important role in the evolution of the pathologic conditions mentioned above.

Resumen Estar bien hidratado se relaciona con un estado adecuado de salud y bienestar; sin embargo ¿qué pasa en los pacientes adultos que tienen algún padecimiento como obesidad, diabetes mellitus tipo 2, hipertensión arterial, cardiopatía isquémica e insuficiencia cardiaca, alteraciones nefrológicas (insuficiencia, poliquistosis y litiasis renal), enfermedad pulmonar obstructiva crónica, dislipidemia, hiperuricemia o, bien, en adultos mayores y en el periodo perioperatorio, en donde hay pérdida del estado de salud o una necesidad diferente de hidratación y que requieren consumir bebidas no alcohólicas para tener un buen estado de hidratación sin alterar la evolución natural de estas condiciones? Algunos puntos y recomendaciones son: la carbonatación de las bebidas ofrece el beneficio de aumentar la saciedad y disminuir la ingesta energética, lo que puede contribuir a la pérdida de peso; el agua simple es la mejor fuente de hidratación en los pacientes diabéticos, sin embargo, otras fuentes de hidratación pueden ser el agua mineralizada, el agua mineral, la leche (de preferencia descremada), café y té sin azúcar o con edulcorantes no calóricos o bajos en calorías, así como cualquier bebida que los contenga; en pacientes con litiasis renal se recomienda ingerir 2.5 a 4 L de agua al día; las bebidas para deportistas pueden ser consumidas por pacientes hipertensos, siempre y cuando no excedan la cantidad de sodio recomendada por la Organización Mundial de la Salud. En conclusión, la hidratación juega un papel importante en la evolución de las enfermedades mencionadas.

Abstract Background: Zapotec is a language used mainly in the state of Oaxaca in Mexico of tonal characteristic; homophone words with difference in fundamental frequency with different meanings. Our objective was to analyze changes in the electroencephalographic (EEG) theta rhythm during word discrimination of lexical tonal bi-syllabic homophone word samples of Zapotec. Methods: We employed electroencephalography analysis during lexical tonal discrimination in 12 healthy subjects 9-16 years of age. Results: We observed an increase in theta relative power between lexical discrimination and at rest eyes-open state in right temporal site. We also observed several significant intra- and inter-hemispheric correlations in several scalp sites, mainly in left fronto-temporal and right temporal areas when subjects were performing lexical discrimination. Conclusions: Our data suggest more engagement of neural networks of the right hemisphere are involved in Zapotec language discrimination.

Resumen Introducción: El zapoteco es un lenguaje hablado principalmente en el estado de Oaxaca, en México, que tiene la característica de ser tonal; es decir, las palabras homófonas que difieren en la altura del fundamental tienen diferente significado. El objetivo de este trabajo fue analizar los cambios del ritmo theta del electroencefalograma en el curso de la discriminación de palabras bisilábicas homófonas en zapoteco. Método: Se empleó el análisis espectral del electroencefalograma durante la discriminación tonal léxica del lenguaje zapoteco en 12 niños sanos de 9-16 años. Resultados: Se observó una mayor potencia relativa theta en la región temporal derecha durante la discriminación léxica en comparación con el registro de reposo-ojos abiertos. También se observaron varias correlaciones significativas intra e interhemisféricas con predominio entre la región frontotemporal izquierda y temporal derecha mientras se realizaba la discriminación tonal léxica. Conclusión: Estos resultados sugieren que hay un mayor compromiso de las redes neuronales en el hemisferio derecho que participan en la discriminación del lenguaje zapoteco.

Resumo Esta é uma síntese enquadrada na Rede de Monitoramento de Habitats Bentônicos Costeiros (ReBentos, GT4: Manguezais e Marismas), embasada em literatura científica que examina interações entre clima e biodiversidade, assim como fatores antrópicos, incluindo aqueles responsáveis pela diminuição da resiliência sistêmica. O objetivo deste trabalho é determinar as dificuldades quanto à detecção de sinais precoces e alertas de mudanças climáticas com dados de monitoramento. No presente trabalho, também foram exploradas formas de contornar os diversos obstáculos identificados. A exposição e a sensitividade de espécies de mangue e de marisma, bem como dos ecossistemas dos quais fazem parte, os tornam extremamente vulneráveis e potenciais indicadores ambientais de mudanças de nível do mar e outras respostas às variações do clima. Entretanto, a interpretação de mudanças em manguezais e marismas e em seus atributos sistêmicos deve ser meticulosa, considerando assinatura energética, regime de distúrbios e pressões ambientais em cada local de estudo. Os potenciais de adaptação e de sobrevivência, em resposta a tais mudanças, dependem da fisiologia de cada espécie e dos processos contextuais onde reside a resiliência e a capacidade de persistir (em níveis local, de paisagem e regionais). A zona costeira deve ser alvo de medidas antecipatórias para redução de riscos por quaisquer impactos, uma vez que nela há intensa convergência de processos sociais e ecológicos. Os ecossistemas dessa zona devem ser integrados em estratégias de adaptação. O manejo costeiro deve ser embasado em mitigação pró-ativa e colaborativa de longo-termo, sempre com base em estudos ecossistêmicos e em programas de monitoramento que possam 1) prover sistema de alerta precoce; 2) preencher lacunas entre correlações simplistas que proveem inferências fracas, e abordagens baseadas em processos que levem a atribuições mais confiáveis e a melhores níveis de antecipação.

Abstract This synthesis is framed within the scope of the Brazilian Benthic Coastal Habitat Monitoring Network (ReBentos WG 4: Mangroves and Salt Marshes), focusing on papers that examine biodiversity-climate interactions as well as human-induced factors including those that decrease systemic resilience. The goal is to assess difficulties related to the detection of climate and early warning signals from monitoring data. We also explored ways to circumvent some of the obstacles identified. Exposure and sensitivity of mangrove and salt marsh species and ecosystems make them extremely vulnerable to environmental impacts and potential indicators of sea level and climate-driven environmental change. However, the interpretation of shifts in mangroves and salt marsh species and systemic attributes must be scrutinized considering local and setting-level energy signature changes; including disturbance regime and local stressors, since these vary widely on a regional scale. The potential for adaptation and survival in response to climate change depends, in addition to the inherent properties of species, on contextual processes at the local, landscape, and regional levels that support resilience. Regardless of stressor type, because of the convergence of social and ecological processes, coastal zones should be targeted for anticipatory action to reduce risks and to integrate these ecosystems into adaptation strategies. Management must be grounded on proactive mitigation and collaborative action based on long-term ecosystem-based studies and well-designed monitoring programs that can 1) provide real-time early warning and 2) close the gap between simple correlations that provide weak inferences and process-based approaches that can yield increasingly reliable attribution and improved levels of anticipation.

Objective To compare performance of children with attention deficit hyperactivity disorders-combined (ADHD-C) type with control children in multi-source interference task (MSIT) evaluated by means of error related negativity (ERN). Method We studied 12 children with ADHD-C type with a median age of 7 years, control children were age- and gender-matched. Children performed MSIT and simultaneous recording of ERN. Results We found no differences in MSIT parameters among groups. We found no differences in ERN variables between groups. We found a significant association of ERN amplitude with MSIT in children with ADHD-C type. Some correlation went in positive direction (frequency of hits and MSIT amplitude), and others in negative direction (frequency of errors and RT in MSIT). Conclusion Children with ADHD-C type exhibited a significant association between ERN amplitude with MSIT. These results underline participation of a cingulo-fronto-parietal network and could help in the comprehension of pathophysiological mechanisms of ADHD.

Objetivo Comparar el rendimiento de un grupo de niños con trastorno por déficit de atención-hiperactividad de tipo combinado (TDAH-C), con niños controles, en la tarea de interferencia multi-fuente (TIMF), evaluado por la negatividad relacionada al error (NRE). Método Estudiamos 12 niños con TDAH-C con una mediana de 7 años, los controles estuvieron pareados por edad y género. Los niños realizaron la TIMF con registros simultáneos de NRE. Resultados No encontramos diferencias en los parámetros de la TIMF entre grupos. No encontramos diferencias en las variables de la NRE entre grupos. Encontramos asociaciones significativas entre la amplitud de la NRE en niños con TDAH-C. Una correlación fue en dirección positiva: (frecuencia de aciertos y amplitud de TIMF), y otras fueron en dirección negativa (frecuencia de errores y el tiempo de respuesta en la TIMF). Conclusión Los niños con TDAH-C presentan una asociación significativa entre la amplitud de la NRE con la TIMF. Los resultados sugieren la participación de la red cíngulo-fronto-parietal y pueden ayudar en la comprensión de los mecanismos fisiopatológicos del TDAH-C.

OBJETIVO: Avaliar a exploração neurofisiológica que identifica esses casos no intraoperatório e que evite o mal posicionamento de parafusos pediculares. MÉTODOS: Em 293 pacientes submetidos à intervenção para escoliose por via posterior com parafusos pediculares e técnica "free hand", foram implantados 6.739 parafusos. Do total, oito pacientes (2,7%) com média de idade de 24 anos, tiveram dor radicular lombar no pós-operatório. Na TC depois da cirurgia, foram encontrados 10 parafusos lombares (2L1-3L2-4L3-1L4) com proeminência mínima na parte inferior do pedículo. Foram avaliados os limiares EMG do parafuso e do trajeto. RESULTADOS: Na cirurgia inicial, não foram detectadas anomalias à palpação do trajeto nem no controle radioscópico; também não se verificaram alterações neurofisiológicas na estimulação neurofisiológica com t-EMG. Todos os pacientes tiveram dor radicular em posição ortostática e sentada, que passava com o repouso na cama. Os parafusos foram retirados cirurgicamente aos 37 dias, em média (R:4-182). Nesta cirurgia repetiu-se a monitoração neurofisiológica, que voltou a mostrar valores normais (> 11mA). Depois da retirada dos parafusos, realizou-se estimulação do trajeto que mostrou, na parte média, limiares inferiores aos valores normais (3,9-10,7mA). Depois de acompanhamento médio de 4,4 anos (R:2,6-6.8), cinco pacientes relatavam incômodos radiculares ocasionais e um tinha déficit motor mínimo no membro afetado. CONCLUSÕES: Apresenta-se um tipo de mal posicionamento de parafuso pedicular lombar que produz radiculalgia em posição ortostática e sentada, que não é detectado pela monitoração convencional. A estimulação neurofisiológica do trajeto na zona média, depois da retirada do parafuso, produziu limiares baixos de estimulação. Recomenda-se a estimulação sistemática do trajeto antes da inserção do parafuso pedicular lombar.

OBJECTIVE: To carry out a neurophysical evaluation that can identify these cases during surgery, and that prevents misplacement of pedicular screws. METHODS: A total of 6739 screws were placed in 293 patients submitted to scoliosis correction via the posterior route with pedicular screws using the freehand technique. Of this total, eight patients (2.7%), with a mean age of 24 years, developed postoperative radiculopathy. Lumbar CT scans showed 10 misplaced lumbar screws (2L1-3L2-4L3-1L4), with minimal protrusion of the lower part of the screw. EMG thresholds of the screw and track were evaluated. RESULTS: In the initial surgery, no anomalies were detected on palpation of the screw track or in the radioscopic control; neither were any neurophysiological alterations detected in the neurophysiological stimulation with t-EMG. All the patients had radicular pain in the standing and seated positions, which disappeared when lying on the bed. The screws were surgically removed at an average of 37 days after surgery (range: 4-182). In this surgical procedure, the neurophysiological monitoring was repeated, again showing normal thresholds (>11mA). After screw removal, stimulation of the probe within the track showed very low thresholds (range: 3.9-10.7 mA) at mid pedicular track. After a mean follow-up time of 4.4 years (Range: 2.6-6.8), five patients reported occasional radicular discomfort, and had minimal motor deficit in the affected limb. CONCLUSIONS: A type of misplacement of lumbar pedicle screws is presented that produces radicular pain in the standing and seated positions, and that may not be detected by conventional monitoring. Neurophysiological stimulation of the mid pedicular track, after removal of the screw, produces low stimulation thresholds. Systematic stimulation of the track prior to insertion of the lumbar pedicular screw is recommended.

OBJETIVO: Valorar una exploración neurofisiológica que identifique estos casos intraoperatoriamente y evite la mal posición de tornillos pediculares. MÉTODOS: En 293 pacientes intervenidos de escoliosis por vía posterior con tornillos pediculares y técnica "free hand", se implantaron 6.739 tornillos. De estos, ocho pacientes (2,7%), con edad promedio de 24 años, presentaron dolor radicular lumbar postoperatorio. En la TC postoperatoria se encontraron 10 tornillos lumbares (2L1-3L2-4L3-1L4) con prominencia mínima en la parte inferior del pedículo. Se evaluaron los umbrales de EMG del tornillo y del trayecto. RESULTADOS: En cirugía inicial no se detectaron anomalías en la palpación del trayecto, ni en el control radioscópico, ni alteraciones neurofisiológicas en la estimulación neurofisiológica con t-EMG. Todos presentaron dolor radicular en bipedestación y sedestación que remitía con reposo en cama. Los tornillos fueron retirados quirúrgicamente a los 37 días en promedio (R:4-182). En esta cirugía se repitió la monitorización neurofisiológica y volvió a mostrar valores normales (> 11mA). Tras la retirada de los tornillos, se realizó estimulación del trayecto que mostró en la parte media, umbrales por debajo de los valores normales (3,9-10,7mA). Tras un seguimiento promedio de 4,4 años (R:2,6-6.8), cinco pacientes referían tener molestias radiculares ocasionales y uno tenía déficit motor mínimo en la extremidad afectada. CONCLUSIONES: Se presenta un tipo de mal posicionamiento de tornillo pedicular lumbar que produce radiculalgia en bipedestación-sedestación y que no es detectado con monitorización convencional. La estimulación neurofisiológica del trayecto en la zona media, tras retirada del tornillo pedicular, produjo umbrales bajos de estimulación. Se recomienda estimulación sistemática del trayecto antes de la inserción del tornillo pedicular lumbar.

Sustainable Management of the Seafront at Tourist Destinations: a Social Perspective on the Project ORLA. The coastal tourist destinations in Brazil have been studied, resulting in a growing need to implement a sustainable management in coastal environments. Thus, the Draft Integrated Seafront (ORLA) is one of the actions of the Ministry of Environment, aiming to promote the occupation of coastal areas. The objective of this study was to understand the perceptions of local residents of the municipality Itapema, Santa Catarina, Brazil, concern to the sustainable management of the coastline, from the implementation of ORLA Project. The research method used is related to interpretive paradigm and it was adopted as a technique for data collection semi-structured interview. The analysis and interpretation of data were based on the method of the Collective Subject Discourse (CSD), which seeks to know the reality presented by the speeches of a significant social representation. The results showed that the implementation of the Linear Park Boardwalk neighborhood in Meia Praia - Itapema (Santa Catarina, Brazil) brought social, economic and environmental issues for the county, increasing the number of visitors and promoting self-esteem of users of the seafront. The project ORLA has contributed to the recognition of landscape and environmental quality of coastal areas, and establishing a plan for the sustainable tourist destination.

Los destinos turísticos del litoral del Brasil han sido objeto de estudio resultando en la necesidad de implementar un gerenciamiento sustentable en los ambientes costeros. Así, el Proyecto de Gestión Integrada de la Orla Marítima (ORLA) constituye una de las acciones del Ministerio de Medio ambiente que busca promover el ordenamiento de los espacios del litoral. El objetivo de este estudio fue conocer la percepción de los pobladores locales del municipio de Itapema, Santa Catarina, Brasil, acerca de la gestión sustentable de la orla marítima mediante el Proyecto ORLA. El método de investigación utilizado estuvo pautado en el paradigma interpretativista y se adoptó como técnica de recolección de datos la entrevista semi-estructurada. El análisis e interpretación de los datos se basó en el método del Discurso del Sujeto Colectivo (DSC), que busca conocer la realidad presentada por medio de los discursos de una representación social significativa. Los resultados mostraron que la implementación del Parque Linear "Calçadão" en el Barrio "Meia Praia", Itapema (Santa Catarina, Brasil) produjo beneficios sociales, económicos y ambientales al municipio; el aumento de visitantes y la promoción de la autoestima de los usuarios de la orla. El proyecto ORLA contribuyó con el reconocimiento de la calidad ambiental y paisajística de los espacios costeros, y con la planificación sustentable del destino turístico.

El Mantenimiento por Diagnóstico de las líneas aéreas de distribución necesita de la valoración objetiva del nivel de deterioro de las mismas, partiendo de la información cualitativa e imprecisa recogida mediante el celaje. Para ello la herramienta matemática idónea es la Lógica Difusa, con la ayuda de la cual se desarrolló el Método de diagnóstico de Líneas aéreas de distribución, con un cuerpo de 108 reglas de implicación, correspondientes a los elementos básicos de la Línea, definidos por la Unión Eléctrica de Cuba.

The Maintenance by Diagnosis of the overhead distribution lines needs of the objective valuation of the deterioration level of the same ones; leaving from the qualitative and imprecise information obtained by lines inspection staff. For it the suitable mathematical tool is the Fuzzy Logic, with the help of the which the Method for the determination of the Line Deterioration Index was developed with 108 implication rules, corresponding to the basic elements of the Line, defined by the Electric Union of Cuba.

O leste do Município de La Pampa, Argentina está em uma área de transição entre o clima temperado e úmido que estende para o leste e o clima de estepe que estende para o oeste, é muito sensível às mudanças no regime de precipitações, especialmente, quando elas ocorrem de forma abrupta, não dando o tempo necessário para levar a cabo medidas adaptativas, para evitar impactos negativos das mudanças climáticas que afetam a produção agrária e o equilíbrio ambiental. Com objetivo de estudar mudanças no regime de precipitação, foram analisadas séries anuais de precipitação (1921 - 2009) de 14 estações da área de estudo, usando uma metodologia de segmentação de séries hidrometeorológicas. Os resultados indicaram que no período de estudo, aconteceram uma sucessão de mudanças abruptas, de sinal positivo em que a precipitação anual aumentou ao redor de 30%. O incremento das precipitações pode ser considerado uma das causas que explicam a expansão da área cultivada nos anos subsequentes a esses aumentos na precipitação. Não obstante, nos últimos anos, foi observada uma mudança abrupta de sinal negativo que reduziu significativamente a precipitação com um retorno marcado para as condições que prevaleceram no início do período analisado. Devido à expansão da agricultura observada no período de incremento das chuvas e, posteriormente, a diminuição dessas chuvas durante um longo período, poderia resultar na queda da produtividade e resultar em uma deterioração ambiental.

The eastern area of the Province of La Pampa, Argentina lies in a transition zone between the humid temperate climate stretching east and the steppe climate stretching west. The area is very sensitive to changes in precipitation patterns, especially when changes are sudden and there is no time to take adaptive measures to cope with the impacts of climate change. In such cases, agricultural production and the balance of the environment are threatened by potential disaster. In order to determine the long-term occurrence of such phenomena, long-term annual precipitation series (1921-2009) from 14 stations in the study area were analyzed using the procedure of hydrometeorological series segmentation. The results for the study period show a succession of abrupt increases, with annual precipitation increasing by about 30%. Each increase in rainfall can be seen as a fostering factor for the expansion of crop planted area in the following years. However, in recent years, there has been an abrupt and significant decrease in precipitation with a marked return to the conditions that prevailed at the beginning of the period. Because agriculture intensified during the period of increased rainfall, the carrying capacity of the environment could be exceeded if rainfall continues to decrease over a long period of time, causing a decline in production accompanied by environmental degradation.

El objetivo del presente estudio cualitativo fue analizar los aspectos morfológicos de la anatomía cerebral interna utilizando imágenes de resonancia magnética (IRM) en dos especies de primates, El mono Araña (A. geoffroyi) y el humano (H. sapiens), tomando como base un estudio comparativo de las estructuras cerebrales de las dos especies, concentrándose primordialmente en el sistema límbico del cerebro del mono araña. Aunque es una especie común en el hemisferio occidental, es interesante para estudiar dada su organización social y funciones motoras, el mono araña (A. geoffroyi) ha sido poco estudiado en cuanto a su neuroanatomía. Las IRM fueron hechas a un mono araña utilizando un resonador General Electrics Signa 1.5 T. Esta investigación se llevo a cabo conforme a las leyes internacionales para la protección de animales en cautiverio y teniendo en cuenta todas las medidas de protección para el manejo experimental para evitar cualquier efecto residual de índole comportamental o fisiológico. Desde un punto de vista cualitativo, los cerebros del mono araña y el humano tenían estructuras similares. Con respecto a la forma, las estructuras más parecidas fueron encontradas en el sistema límbico, sin embargo la curvatura cervical, la amígdala, el hipocampo, la comisura anterior y el colículo fueron más grandes proporcionalmente en el mono araña que en el humano.

The objective of the present qualitative study was to analyze the morphological aspects of the inner cerebral anatomy of two species of primates, using magnetic resonance images (MRI): spider monkey (A. geoffroyi) and human (H. sapiens), on the basis of a comparative study of the cerebral structures of the two species, focusing upon the brain of the spider monkey and, primarily, its limbic system. In spite of being an endemic Western hemisphere species, a fact which is by its own right interesting for research due to this animal’s social organization and motor functions, the spider monkey (A. geoffroyi) has hardly been studied in regard to its neuroanatomy. MRI was carried out, in one spider monkey, employing a General Electric Signa 1.5 T scanner. This investigation was carried in accordance to international regulations for the protection of animals in captivity, taking into account all protective means utilized in experimental handling, and not leaving behind any residual effects, either physiological or behavioral. From a qualitative point of view, the brains of the spider monkey and the human were found to have similar structures. In reference to shape, the most similar structures were found in the limbic system; proportionally, however, cervi cal curvature, amygdala, hippocampus, anterior commissure and the colliculi, were larger in the spider monkey than in the human.

Este artigo objetiva abordar a inter-relação entre os conceitos de Gestão do Conhecimento e Valor Percebido. Ocupa-se, também, de constatar a relevância da gestão do conhecimento como elemento diferenciador no processo de entrega de valor para os clientes. Apresenta, inicialmente, conceituação básica sobre gestão do conhecimento e valor percebido. Em seguida, são introduzidas idéias sobre identificação e construção de valor para os clientes. Após isso, há a contextualização do tema, abordando-se o valor percebido e o conhecimento e sua gestão do ponto de vista negocial. Analisa-se, a partir disto, uma pesquisa sobre a percepção de altos executivos em relação ao seu grupo de trabalho e conclui-se com apresentação da importância do conhecimento para o processo de construção de valor percebido, com exemplificação e concepção de diagrama de inter-relação dos conceitos.

This article aims to approach the interconnection between the Knowledge Management and the Perceived Value concepts. It also evidences the relevance of knowledge management as a differentiating element in the process of value delivery to the clients. Initially, it presents a basic conception on the knowledge management and perceived value. Following, ideas about the value identification and construction for the clients are introduced. Then, the subject is contextualized, approaching the perceived value and knowledge and its management from the business point of view. From those aspects, a survey on the perceptions of high executives is analyzed with respect to their work groups and the study is concluded with the importance of knowledge for the perceived value construction process, with the exemplification and conception of a concept interrelation diagram.

Summary: Action of GABA agonists and antagonists on memory. The θ rhythm. Muscimol may directly alter memory. Recently, a modified matching to position (MTP) paradigm was employed aimed at influencing the type of associations a rat may use to solve the task. The main behavioral manipulation was the application of a differential outcomes procedure (DOP). DOP implies correlating each event to be remembered with a different reward condition. This procedure will result in the development of specific reward expectations which will in turn increase and guide choice behavior. Such different reward expectations will not be present when the reward assignation used is either common or random (non-differential outcomes procedure, NOP). Intraventricular infusion of muscimol or CSF in rats carrying out a delayed MTP using either a MOP or an NOP protocol will affect both groups of rats, but the nature of the deficit will differ depending on the reinforcement contingencies. Rats trained in DOP will show general non-mnemonic damage independent of delay, i.e., performance will be affected at all delay intervals employed. On the contrary, rats trained in NOP will show delay-dependent damage. This appears to demonstrate that muscimol may also have untoward memory effects, which further indicates that activation of GABA receptors will affect a set of memory associations and functions. Difficulties experienced in the past regarding LTP induction at the level of the CA3-CA1 synapse using time-based spike presentation protocols have been disconcerting given the preeminence of these synapses as a model system for the study of synaptic plasticity. Results previously discussed in experiments using picrotoxin as a GABA inhibitor have suggested that such difficulties arise from the requirement that, for LTP to be induced, CA1 dendrites must be persistently and totally activated. Doublets used in this case represent a minimal burst, or level of post-synaptic stimulation for LTP induction that subsumes greater depolarizations. In vitro, synaptically induced bursts would correspond to regenerative electrical events in apical dendrites of pyramidal neurons. The same requirements for dendritic activation would be satisfied in vivo during the θ rhythm, which is present during active exploration. Therefore, GABA might serve as an engram modulator through the activation of the hippocampal θ rhythm. Effect of μ-opioid receptors on hippocampal memory activity. Hippocampal μ-opioid receptors (MOR) have been involved in the formation of memory associated with the abuse of opioid drugs. When chronically activated, and during programmed drug abstinence, MORs acutely modulate hippocampal synaptic plasticity At the level of neuronal networks, MORs increase excitability of area CA1 by means of a disinhibition of pyramidal cells. The specific inhibitory interneuronal subtypes which become affected by activation of MORs are not known. Nevertheless, not all subtypes are inhibited and some subtypes preferentially express these receptors. In one study, the effect of activation of MORs on inhibitory patterns and propagation of excitatory activity in CA1 of rat hippocampus was investigated through cortical images created using voltage-sensitive dyes. MOR activation increased excitatory activity originated by the increased stimulating input to stratum oriens (i.e., Schäffer collateral and commissural [SCC] fibers, as well as the retrograde pathway), to stratum radiatum (i.e., SCC fibers) and to stratum lacunosum-moleculare (i.e., the perforant pathway and the thalamus). Increased excitatory activity was additionally facilitated by propagation through the neural network of area CA1. This was observed as a proportionally greater increment of amplitudes of excitatory activity in sites distant from the originally evoked activity. Such facilitation was noted in excitatory activity propagating from three sites of stimulation. The increment and facilitation were prevented with GABAA receptor antagonists (bicuculline, 30 μM), but not with GABAB receptor antagonists (CGP, 10 μM). Besides, MOR activation inhibited inhibitory post-synaptic potentials (IPSPs) in every layer of area CA1. These findings suggest that MOR-originated suppression of GABA release to GABAA receptors increases every type of input to pyramidal CA1 neurons and facilitates propagation of excitatory activity through the neural network of area CA1. Cannabis indica and memory. Cannabinoids (derived from Cannabis indica, or marihuana) disturb memory processes in mammalians. In spite of the fact that the neuronal cannabinoid CB1 receptor was identified several years ago, the neuronal network mechanisms mediating these effects are still controversial. Tritium-labeled GABA-releasing experiments have been used to test for the localization of this receptor at a cellular and subcellular level in the human hippocampus. CB1 expression detected with this technique is limited to hippocampal interneurons, most of which, it could be determined, are cholecystokinin-containing basket neurons. The CB1-positive neuronal somata show immune staining of their cytoplasm, but not of their somatodendritic plasma membrane. CB1-immunoreactive axonic terminals densely cover the entire hippocampus and form symmetrical synapses, characteristic of GABAergic neuronal boutons. It could thus be observed that WIN 55,212-2, a CB1-receptor agonist, considerably reduces the release of tritium-labeled GABA, and that this effect is preventable using the receptor antagonist, SR 141716A. This single pattern of expression and pre-synaptic modulation of GABA release suggests the existence of a preserved role of CB1 receptors in the control of inhibitory hippocampal networks responsible for the generation and maintenance of fast and slow oscillation patterns. Therefore, a probable mechanism whereby cannabinoids could affect associational processes in memory might be a disturbance of synchrony of rhythmical events in distinct neuronal populations. GABA effects against aging. Certain components which stimulate GABAergic neurotransmission might prevent the hippocampal and striatal degeneration which typically appears with old age and causes memory deterioration. On using a 4-vessel occlusion model in animals to study the effect of ischemia on expression of GABAA receptor subunits, which are vulnerable in region CA1 and resistant in region CA3 of Amnion's horn, an increment in expression of GABAA2, GABA B2, GABA G2 units and a decrement in expression of GABA A1 and GABA A3 subunits in region CA3 were obtained. On the contrary, there was no change in region CA1 or the dentate gyrus under the same conditions. These data speak in favor of the stimulation of type 2 receptor GABAergic subunits which might protect certain hippocampal areas against a harmful neurodegenerative effect, for example, of memory activities during old age.

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Summary: Introduction. The entire hippocampus is derived from the telencephalon. Embryologically, it is made up of the most archaic cortices. Through special phylogenetic and ontogenetic telencephalization processes, it will arrive at its particular mesial basal position. This structure has three components: a) Retrocommisural hippocampus, or hippocampus proper (RH). b) Supracommisural hippocampus (SH). c) Precommisural hippocampus (PH). The RH is situated in the most medial part of the 5th temporal gyrus (5 TG). The outer/upper face of the RH is to be found in the temporal recess of the lateral ventricle. It is called pes hippocampi or albeus. Inwards, it is limited by the choroid fissure, outwards and downwards by the parenchyma of the 5th TG, forwards, by the amygdala of the striatal body and, backwards, by the isthmus. The fornix is a continuation of efferent pathways from CA3, CA1 and the subiculum. By means of a circular course, it ascends over the thalamus and, descending in front of Monro's foramina and traversing the hypothalamus, reaches the mammillary bodies. It consists of fimbria, posterior pillars and a body and anterior pillars. The latter pass behind the anterior white commisure (AWC), and make up the anterior portion of Monro's foramina. The SH originates in the RH. At the level of the splenium of the corpus callosum (CC), the fornix produces two striae, medial and lateral, and the dentate gyrus turns from fasciola cineria into induceum griseum. These structures are to be found in both hemispheres and, traveling over the CC, will reach the preoptic and hypothalamic septal areas, as well as the PH. The PH is a small fiber contingent which stems from the fornix at the level and in front of the AWC. Memory. General aspects. There is general agreement that the main role of the hippocampus is that of creating new memories relative to experienced events (episodic or autobiographic memory). Some researchers, however, prefer to think of the hippocampus as part of a major medial temporal lobe memory system responsible for declarative memory. This memory would include, besides episodic memory, memory of events. Another very important hippocampal function would relate to storage of semantic (conceptual) memories. Engrams. Memory and synaptic plasticity. Engrams are hypothetical means whereby memory traces are stored as physical or chemical changes in the brain in response to external stimuli. The existence of engrams has been proposed by diverse scientific theories which try to explain the persistence of memory and how some memories are stored in the brain. The term engram was coined by Sermon and explored by Pavlov Lashley tried to locate the engram and failed in finding a sole biological locus for the same which made him think that memories were not localized in any particular part of the brain, but distributed throughout the cerebral cortex. Afterwards, in 1949, Hebb, a student of Lashley's, published his empiricist theories in The Organization of Behavior. Hebb referred to Lorente de Nó's reverberating circuits to propose a mechanism for maintaining activity in the cerebral cortex after the external stimulus had ceased: the so called central autonomous process. This led him to consider the cellular assembly, a complex reverberating circuit which could be assembled by experience. Changes in synaptic resistance with experience were eventually named Hebb's, or the Hebbian, synapse. Hebbian theory describes a basic mechanism for synaptic plasticity by means of which an increment in synaptic efficacy stems from repetitive and persistent stimulation of the post-synaptic cell. This theory receives the name of Hebb's rule. The fact that memory is persistent stresses the relevance of understanding those factors which maintain synaptic strength and prevent undesired synaptic changes. There is evidence that recurrent inhibitory connections in region CA1 of Ammon's horn of the hippocampus might contribute in this sense by modulating the ability to induce long-term potentiation (LTP) or long-term depression (LTD) of synaptic activity, given by a sequence of high-or low-frequency stimulations, respectively. The hippocampus seems to be able to select the most relevant from the least relevant aspects of a definite experience in order to transform them into long-term memory. According to the concept of Emotional Tagging, for example, through the activation of the amygdala by emotionally suggestive events, the experience will be tagged as important and synaptic plasticity promoted in other cerebral regions, such as the hippocampus. Recently, it has been shown that activation of the amygdala transforms transient plasticity into long-term plasticity. This finding directly relates to the afore mentioned hypothesis of emotional tagging, since activation of this organ could trigger neuromodulatory systems, further reduce the activation threshold of the synaptic marker and facilitate transformation of early into late memory at the level of the hippocampus via direct amygdalar action on the latter organ. γ-aminobutyric acid. γ-aminobutyric acid (GABA), together with its different receptor subunits, functions as an inhibitor neurotrans-mitter in hippocampus and memory activities. GABA and memory. LTP has been a widely studied mechanism of synaptic plasticity and, as we have mentioned, it is intimately related to diverse memory and learning processes in mammals. It has been observed in pyramidal cells of area CA1 of the hippocampus of young C57BL/6 mice that the pairing of pre-synaptic stimulation with just one post-synaptic action potential will be sufficient to induce LTP, whereas in the adult animal this stimulation must be paired with several post-synaptic action potentials to achieve such induction. This change might result from a modification during maturation of GABAergic inhibitory processes. A bath of muscimol, a GABAA agonist, given to sections of hippocampal area CA1 will increase the range of frequencies inducing LTD, while in the presence of picrotoxin, a GABAA antagonist, LTD will be induced only at very low stimulation frequencies. The resulting recurrent inhibition appears to stem from GABAergic input to pyramidal neurons of CA1. In this way, post-synaptic spike activity could increase GABAergic feedback inhibition, and thus favor LTD. However, in experiments in which the pairing of stimulating action potentials is set apart in time, LTD, LTP or no plasticity may be observed. An explanation for these results could be that, in the presence of picrotoxin, and therefore GABA inhibition, the first action potential may have a greater tendency to "back propagate", so that only one spike would be enough to cause LTP instead of LTD, and affect memory processes differently.

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Introduction. Pediatric intracranial tumors (PIC) make up the most frequent solid neoplastic pathology in children. We present an analysis of the experience of Hospital Infantil de Mexico Federico Gomez (HIMFG), in Mexico City, over the course of 36 years in this regard. Material and methods. Cases from the archives of the Department of Clinical Records, Department of Neurosurgery and Department of Pathology at HIMFG were used for this analysis. Results were compared to data published by the Hospital for Sick Children of Toronto (HSCT) and by Instituto Nacional de Pediatria (INP) in Mexico City. Results. Of 810 cases reviewed at HIMFG, 55% belonged to the male gender. By age, older-infant and grade-school-children cases predominated (> 50%). Of those, 397 cases were supratentorial and 413 infratentorial. Most frequent tumors were: astrocytomas (23%), medulloblastomas , craniopharyngiomas (11%) and ependymomas (10%). Fifth place was occupied by germinomas (4%). Mixed gliomas, meningiomas, primitive neuroectodermal tumors and ependymoblastomas were the last (1 to 3%). Conclusions. At HIMFG, the most frequent tumour types were: astrocytomas, medulloblastomas, craniopharyngiomas and ependymomas. Since the 70s, on the number of patients presenting with intracranial tumors at HIMFG has grown exponentially, and the amount carried out till now at this hospital parallels, or slightly exceeds, that carried out at similar institutions in Mexico and abroad.

Introducción. Los tumores intracraneanos (TIC) pediátricos son las neoplasias sólidas más frecuentes en niños. Se presenta la experiencia del Hospital Infantil de México Federico Gómez (HIMFG) de los últimos 36 años. Material y métodos. Se utilizaron los siguientes archivos del HIMFG: Clínico, de los Departamentos de Neurocirugía y de Patología. Los resultados se compararon con los datos del Hospital for Sick Children de Toronto y del Instituto Nacional de Pediatría de México, D. F. Resultados. En el HIMFG, 55% de los pacientes eran del sexo masculino. Predominaron desde lactantes mayores hasta escolares, con más de 50%. Los tumores fueron: 397 supratentoriales y 413 infratentoriales. Los más frecuentes fueron: astrocitomas (32%), meduloblastomas (19%), craneofaringiomas (11%) y ependimomas (10%); en el quinto lugar quedaron los germinomas (4%). Los gliomas mixtos, los meningiomas, los tumores neuroectodérmicos primitivos y los ependimoblastomas representaron de 1 a 3%. Conclusiones. En el HIMFG, los 4 tipos más frecuentes de tumor fueron: astrocitomas, meduloblastomas, craneofaringiomas y ependimomas. El trabajo de campo del HIMFG ha tenido un desarrollo exponencial desde la mitad de los años setenta. Actualmente, el volumen de pacientes manejado por el HIMFG es semejante a, o rebasa discretamente, al de otras instituciones.

Abstract: Neurotransmitters of the amygdala in the limbic system include monoamines (noradrenaline [NA]) acetylcholine (ACh), corticoids and histamine. Drugs infused into the amygdala may modulate consolidation in memory of inhibition of training directed to avoid stressful situations. Administration of antagonists of β NA receptors to the amygdala will affect retention in memory for a whole day when given immediately after training, but will have no effect when given six hours after training a test animal. Intra-amygdalar infusions of NA which may be accompanied by antagonists of those receptors will attenuate the memory disturbance. It is worth mentioning that later studies have been able to show that NA will produce an increment of memory consolidation, which will depend on the time as well as on the dose of application, when the drug is infused to the amygdala shortly after inhibition of training directed to avoid stressful situations. The amygdala, the neocortex and the hippocampus are target regions of the frontal basal cholinergic brain system, which has different effects on cognitive functions, such as memory and learning. Any neurotransmitter with phosphorylating or dephosphorylating activity may regulate the sensitive state of ACh, as well as the functional properties of amygdalar neurons. It is possible, then, that modulation mechanisms may exist between learning and recall states in the amygdala, the neocortex and the hippocampus, which could be controlled by muscarinic acetylcholinergic receptors. Through pre-synaptic receptors of histamine 3 (H3) and a currently unknown mechanism, histamine will decrease or increase excitatory synaptic transmission in BLA. Such histaminergic modulation of neuronal activity will play an important role in fear-related physiological and patho-physiological processes, learning and memory of emotion, and affective disturbances.

Resumen: Los neurotransmisores de la amígdala en el sistema límbico comprenden, entre otros, a las monoaminas (noradrenalina [NA]), la acetilcolina (ACh), los corticoides y la histamina. Ciertas drogas infundidas a la amígdala podrían modular la consolidación en la memoria de la inhibición del entrenamiento dirigido a evitar situaciones de estrés. La administración de anta gonistas de los receptores de la β NA en la amígdala afecta la retención en la memoria por un lapso de un día cuando se administra inmediatamente después del entrenamiento, pero no surte ningún efecto cuando se administra a las seis horas. Infusiones intraamigdalinas de NA acompañadas de antagonistas de aquellos receptores atenuarán el trastorno mnemónico. De manera importante, se ha podido determinar que la NA produce un incremento de la consolidación de la memoria, que depende tanto del tiempo como de la dosis de aplicación cuando el fármaco se infunde a la amígdala inmediatamente después de la inhibición de este tipo de entrenamiento. La amígdala, la neocorteza y el hipocampo son regiones meta del sistema cerebral frontal basal colinérgico, que se relaciona estrechamente con diversas funciones del aprendizaje y la memo ria. Cualquier neurotransmisor con actividad fosforiladora o desfosforiladora podrá regular el estado de sensibilidad a la ACh, así como las propiedades funcionales de las neuronas amigdalinas. Es posible, entonces, que exista una modulación entre los estados de aprendizaje y de recuerdo de lo aprendido en la amígdala, la neocorteza y el hipocampo que esté regida por receptores muscarínicos acetilcolinérgicos. Por medio de receptores presinápticos de la histamina 3 (H3) y un mecanismo por el momento aún desconocido, la histamina disminuye o aumenta la transmisión sináptica excitadora en el BLA. Tal modulación histaminérgica de la actividad neuronal cumple un papel importante en los procesos fisiológicos y patofisiológicos del miedo, el aprendizaje y la memoria de la emo ción y los trastornos afectivos.