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El riego complementario permite incrementar y estabilizar los rendimientos de los cultivos de granos. Sin embargo, cuando se utilizan aguas de mala calidad, pueden generar procesos de degradación de las propiedades edáficas. El objetivo del trabajo fue evaluar el impacto del riego complementario, con agua de baja conductividad eléctrica y sodicidad intermedia, sobre algunas propiedades físicas y químicas de un suelo Argiudol típico, franco, en siembra directa. Los tratamientos fueron: i: Riego durante 13 años; ii: Secano en zonas adyacentes (esquinas). Las propiedades se evaluaron en tres sectores dentro del lote diferenciando en círculo de riego y esquinas, con un diseño de t-apareado. El tratamiento Riego incrementó significativamente el pH y el porcentaje de sodio intercambiable (P0,05). La resistencia a la penetración fue superior a 2 MPa en ambos tratamientos en todo el perfil medido (0-40 cm), lo cual estuvo posiblemente asociado al tránsito vehicular y la cosecha en suelo húmedo. La estabilidad de agregados fue muy alta en ambos tratamientos, atribuible al contenido elevado de materia orgánica en superficie y al manejo en siembra directa.Supplementary irrigation increases and stabilizes crop yields. However, when irrigation water of poor quality is applied, it can adversely affect soil properties. The objective of this study was to: evaluate the influence of supplementary irrigation on some physical and chemical properties under no- till cultivation systems. A field experiment was performed on a loamy Typical Argiudoll, managed under no- tillage. The treatments were: 1-Irrigated soil during 13 years, 2-Adjacent Rainfed soil. Soil chemical (pH, electric conductivity, exchangeable sodium percentage, organic carbon, total N, exchangeable cations, cation exchange capacity, extractable P) and physical properties (infiltration rate, soil penetration resistance, bulk density, gravimetric water content, structural instability) were evaluated. Irrigation significantly increased the pH and exchangeable sodium percentage (P 2Mpa) in both treatments, probably due to the effects of the cultivation and harvest machinery under high soil water contents. The soil structural instability was very low (i.e. high structural stability) in both treatments, probably associated to the high organic matter content and the no- till cultivation system.

We previously obtained evidence in rainbow trout peripheral tissues such as liver and Brockmann bodies (BB) for the presence and response to changes in circulating levels of glucose (induced by intraperitoneal hypoglycaemic and hyperglycaemic treatments) of glucosensing mechanisms others than that mediated by glucokinase (GK). There were based on mitochondrial production of reactive oxygen species (ROS) leading to increased expression of uncoupling protein 2 (UCP2), and sweet taste receptor in liver and BB, and on liver X receptor (LXR) and sodium/glucose co-transporter 1 (SGLT-1) in BB. We aimed in the present study to obtain further in vitro evidence for the presence and functioning of these systems. In a first experiment, pools of sliced liver and BB were incubated for 6h at 15°C in modified Hanks' medium containing 2, 4, or 8mM d-glucose, and we assessed the response of parameters related to these glucosensing mechanisms. In a second experiment, pools of sliced liver and BB were incubated for 6h at 15°C in modified Hanks' medium with 8mM d-glucose alone (control) or containing 1mM phloridzin (SGLT-1 antagonist), 20μM genipin (UCP2 inhibitor), 1μM trolox (ROS scavenger), 100μM bezafibrate (T1R3 inhibitor), and 50μM geranyl-geranyl pyrophosphate (LXR inhibitor). The results obtained in both experiments support the presence and functioning of glucosensor mechanisms in liver based on sweet taste receptor whereas in BB the evidence support those based on LXR, mitochondrial activity and sweet taste receptor.

Active fractions of organic matter have been proposed as early indices of changes in soil organic carbon (organic-C) induced by management. We performed a meta-analysis of published results from 31 field experiments conducted in the Pampas in which tillage and rotation effects on organic-C, microbial biomass carbon (microbial-C), light fraction carbon (light-C), particulate carbon (particulate-C) and basal respiration (mineralized-C) were assessed. We compared the changes of organic-C and the four active fractions between management treatments sampled at the same date and depth within each experiment. Pooling all the experiments, active fractions-C varied on average 1.2- to 3.0-fold more than organic-C, depending on the fraction considered, but these average changes were significantly greater than organic-C changes only for particulate-C. This later fraction showed to be more sensitive to agricultural practices than organic-C. In experiments in which organic-C changes were lower than 15–25%, the four labile fractions may show opposite trends than organic-C. Above this threshold, changes of active fractions generally copied organic-C changes and were greater. Consequently, the active fractions may be used as indicators of changes in organic-C only when this latter variable has already suffered a huge change. In these cases, it will be easier to simply measure organic-C. Fil: Alvarez, Carina Rosa. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Agronomía; Argentina Fil: Alvarez, Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Agronomía; Argentina

We previously obtained evidence in rainbow trout for the presence and response to changes in circulating levels of glucose (induced by intraperitoneal hypoglycaemic and hyperglycaemic treatments) of glucosensing mechanisms based on liver X receptor (LXR), mitochondrial production of reactive oxygen species (ROS) leading to increased expression of uncoupling protein 2 (UCP2), and sweet taste receptor in the hypothalamus, and on sodium/glucose co-transporter 1 (SGLT-1) in hindbrain. However, these effects of glucose might be indirect. Therefore, we evaluated the response of parameters related to these glucosensing mechanisms in a first experiment using pooled sections of hypothalamus and hindbrain incubated for 6 h at 15°C in modified Hanks9 medium containing 2, 4 or 8 mmol l −1 d-glucose. The responses observed in some cases were consistent with glucosensing capacity. In a second experiment, pooled sections of hypothalamus and hindbrain were incubated for 6 h at 15°C in modified Hanks9 medium with 8 mmol l −1 d-glucose alone (control) or containing 1 mmol l −1 phloridzin (SGLT-1 antagonist), 20 µmol l −1 genipin (UCP2 inhibitor), 1 µmol l −1 trolox (ROS scavenger), 100 µmol l −1 bezafibrate (T1R3 inhibitor) and 50 µmol l −1 geranyl-geranyl pyrophosphate (LXR inhibitor). The response observed in the presence of these specific inhibitors/antagonists further supports the proposal that critical components of the different glucosensing mechanisms are functioning in rainbow trout hypothalamus and hindbrain.

Different clays of the state of Guanajuato were mixed and their properties were analyzed in order to select the best ceramic paste. The best mixture showed an excellent plastic molding and a linear contraction of 4,61% during the drying process. This process was analyzed using the Bigot curve at two different temperatures (60 and 80°C). The optimal firing temperature was 1030 °C. After the fi ring process, the pieces showed 12,3 % water absorption, 5,4 % contraction, a 91 HRB hardness and a compressive strength of 35 Kg/cm2. Se mezclaron varias arcilla del estado de Guanajuato y se determinaron sus propiedades con el objeto de identifi car la mejor pasta cerámica. La mejor mezcla mostró una excelente plasticidad para el moldeo y una contracción lineal durante el secado de 4,61%. El proceso de secado fue analizado con la curva de Bigot a dos temperaturas (60°C y 80°C) y la cocción óptima de la pasta fue a 1 030°C. Después de ser cocidas, las piezas presentaron un 12,3 % de absorción de agua, 5,4% de contracción, 91 de dureza Rockwell B y 35 kg/cm2 de resistencia a la compresión.

One of the expected benefits of no-tillage systems is a higher rate of soil C sequestration. However, higher C retention in soil is not always apparent when notillage is applied, due e.g., to substantial differences in soil type and initial C content. The main purpose of this study was to evaluate the potential of no-tillage management to increase the stock of total organic C in soils of the Pampas region in Argentina. Forty crop fields under no-tillage and conventional tillage systems and seven undisturbed soils were sampled. Total organic C, total N, their fractions and stratification ratios and the C storage capacity of the soils under different managements were assessed in samples to a depth of 30 cm, in three layers (0-5, 5-15 and 15-30 cm). The differences between the C pools of the undisturbed and cultivated soils were significant (p < 0.05) and most pronounced in the top (0-5 cm) soil layer, with more active C near the soil surface (undisturbed > no-tillage > conventional tillage). Based on the stratification ratio of the labile C pool (0-5/5-15 cm), the untilled were separated from conventionally tilled areas. Much of the variation in potentially mineralizable C was explained by this active C fraction (R 2 = 0.61) and by total organic C (R 2 = 0.67). No-till soils did not accumulate more organic C than conventionally tilled soils in the 0-30 cm layer, but there was substantial stratification of total and active C pools at no till sites. If the C stratification ratio is really an indicator of soil quality, then the C storage potential of no-tillage would be greater than in conventional tillage, at least in the surface layers. Particulate organic C and potentially mineralizable C may be useful to evaluate variations in topsoil organic matter. Um dos benefícios esperados do uso do plantio direto é um maior sequestro de C. Contudo, nem sempre se observa maior retenção de C no solo quando esse sistema de preparo é utilizado, devido principalmente às diferenças em tipo de solo e conteúdo inicial de C, entre outras. O objetivo deste trabalho foi avaliar o potencial do plantio direto para estocar C orgânico nos solos da Região do Pampa Argentino. Foram coletadas amostras de solo em 40 áreas sob plantio direto ou preparo convencional e em sete campos não cultivados por vários anos. Determinaram-se o C orgânico total, N total, suas frações lábeis, sua taxa de estratificação e a capacidade de estocar C dos solos sob diferentes manejos, na camada de 0-30 cm de profundidade, a qual foi dividida, para fins de amostragem, em três profundidades (0-5, 5-15 e 15-30 cm). Verificou-se diferença significativa (p < 0,05) para todos os pools de C entre os solos não cultivados e os cultivados. A diferença mais pronunciada foi verificada na camada superficial (0-5 cm), sendo determinado o maior teor de C lábil próximo da superfície do solo (não perturbado > plantio direto > preparo convencional). A taxa de estratificação do C lábil (0-5/5-15 cm) permitiu separar as áreas sob plantio direto daquelas sob preparo convencional. Boa parte da variação em C potencialmente mineralizável foi explicada pela fração lábil do C (R2 = 0,61), assim como pelo C orgânico total (R2 = 0,67). Os solos sob plantio direto não estocaram mais C orgânico do que os preparados de maneira convencional, na camada de 0-30 cm. Entretanto, houve substancial estratificação dos pools de C lábil nos locais sob plantio direto, indicando que, se a taxa de estratificação for realmente um indicador de qualidade de solos, as áreas sob plantio direto poderiam ter maior potencial de acúmulo de C, pelo menos nas camadas superficiais de solo, se comparada com as áreas sob preparo convencional. O C orgânico particulado e o C potencialmente mineralizável podem ser utilizados para avaliar variações na matéria orgânica da camada superficial do solo. Fil: Alvarez, Carina Rosa. Universidad de Buenos Aires. Facultad de Agronomía; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Costantini, Alejandro Oscar. Universidad de Buenos Aires. Facultad de Agronomía; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria; Argentina Fil: Bono, Alfredo. Instituto Nacional de Tecnología Agropecuaria. Centro Regional La Pampa-San Luis. Estación Experimental Agropecuaria Anguil; Argentina Fil: Taboada, Miguel Angel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria; Argentina. Universidad de Buenos Aires. Facultad de Agronomía; Argentina Fil: Gutiérrez Boem, Flavio Hernán. Universidad de Buenos Aires. Facultad de Agronomía; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Fernández, Patricia Lilia. Universidad de Buenos Aires. Facultad de Agronomía; Argentina Fil: Prystupa, Pablo. Universidad de Buenos Aires. Facultad de Agronomía; Argentina

Objective. To study asthma-related absenteeism in the asthmatic population in Spain and to identify some risk factors for absenteeism. Methods. A cross-sectional study was performed on patients who had been diagnosed with asthma in the primary care setting at least 1 year before the start of this study. A questionnaire was designed that included socio-demographic and clinical variables. The time absent from work in the previous year was self-reported by the patients. Results. More than 25% of the asthmatic population in Spain took sick leave during the previous year. Visits to a general practitioner or to the emergency department are the factors associated with the greatest risk of absenteeism. Conclusions. Absenteeism is common within the asthmatic population in Spain. The authors of this study believe that some of the determining factors could be modified by the health-care system.

The Proctor test is time-consuming and requires sampling of several kilograms of soil. Proctor test parameters were predicted in Mollisols, Entisols and Vertisols of the Pampean region of Argentina under different management systems. They were estimated from a minimum number of readily available soil properties (soil texture, total organic C) and management (training data set; n = 73). The results were used to generate a soil compaction susceptibility model, which was subsequently validated using a second group of independent data (test data set; n = 24). Soil maximum bulk density was estimated as follows: Maximum bulk density (Mg m-3) = 1.4756 - 0.00599 total organic C (g kg-1) + 0.0000275 sand (g kg-1) + 0.0539 management. Management was equal to 0 for uncropped and untilled soils and 1 for conventionally tilled soils. The established models predicted the Proctor test parameters reasonably well, based on readily available soil properties. Tillage systems induced changes in the maximum bulk density regardless of total organic matter content or soil texture. The lower maximum apparent bulk density values under no-tillage require a revision of the relative compaction thresholds for different no-tillage crops. A prova de Proctor consome tempo e requer a amostragem de grande quantidade de solo. Neste estudo, os parâmetros da prova de Proctor foram preditos em Molisols, Entisols e Vertisols da região do Pampa Argentino sob diferentes manejos. Para isso, partiu-se de um número mínimo de propriedades do solo facilmente disponíveis, como textura do solo e teor de matéria orgânica, e do manejo adotado. Os resultados foram usados para gerar um modelo de suscetibilidade, que foi logo validado utilizando um segundo grupo de dados independentes. O manejo foi igual a 0 para os solos não trabalhados e sob plantio direto e 1 para os solos manejados sob plantio convencional. Os modelos obtidos predisseram razoavelmente os parâmetros da prova de Proctor partindo de propriedades do solo facilmente disponíveis. Os sistemas de preparo induziram mudanças na máxima densidade aparente apesar dos conteúdos de matéria orgânica e textura do solo. Os menores valores máximos de densidade aparente do solo obtido sob plantio direto tornam necessária uma revisão dos limites de compactação relativa para diferentes cultivos manejados com plantio direto. Fil: Alvarez, Carina Rosa. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Ingeniería Agrícola y Uso de la Tierra. Cátedra de Fertilidad y Fertilizantes; Argentina Fil: Micucci, Federico Guillermo. Merk Crop Bioscience Argentina S.A. ; Argentina Fil: Bustingorri, Carolina. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Ingeniería Agrícola y Uso de la Tierra. Cátedra de Fertilidad y Fertilizantes; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones en Biociencias Agrícolas y Ambientales. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones en Biociencias Agrícolas y Ambientales; Argentina Fil: Taboada, Miguel Angel. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Suelos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

The grazing of crop residues during the winter in integrated crop–livestock systems can either increase soil bulk density (BD) by compaction or decrease BD by swelling, as a function of gravimetric soil water content (GW) during grazing. A field experiment was conducted from 2005 to 2008 to evaluate the BD response to grazing in a no-till silty loam soil (Typic Argiudoll) of the Pampas region of Argentina. Soil BD (core method), GW data and the calculated air volume (AV) were obtained from the 0–50 mm and 50–100 mm layers at different sampling times from ungrazed and grazed treatments. Over most of the study period (2006 through 2008) soil BD showed little impact from grazing, with minimal temporal variation (1.32–1.46 Mg m−3). This stable behavior was ascribed to low rainfall and relatively low GW values at the time when soil was trampled by livestock and routinely trafficked by machinery. Soil BD in the upper (0–50 mm) layer was significantly (p 330 g kg−1 in the ungrazed treatment and GW was > 240 g kg−1 in the grazed treatments. Grazing accentuated the soil kneading process that promoted air entrapment. Our results suggest in this no-tilled silt loam soil that winter grazing of crop residues caused no deterioration of topsoil porosity in the no-tilled silty loam soil.

Resumen Introduccion El control del asma es inadecuado en todas las poblaciones estudiadas hasta el momento actual, generando la mayor parte de los costes de la enfermedad. El obejtivo de nuestro estudio fue evaluar la prevalencia de asma mal controlada en pacientes de atencion primaria, e identificar algunos factores asociados con este hecho. Metodos Llevamos a cabo un estudio transversal, incluyendo pacientes asmaticos mayores de 18 anos, seguidos en consultas de atencion primaria (n=2159). El control del asma se evaluo con el cuestionario «Asthma Control Questionnaire». Las variables sociodemograficas y el cumplimiento terapeutico se evaluaron mediante un cuestionario. Mediante regresion logistica se calcularon los OR de asma mal controlada; utilizando como variable dependiente el control del asma, valorado de acuerdo a la puntuacion ACQ. Resultados La prevalencia de asma no controlada fue del 63,9%. El tratamiento con corticoides orales (OR=6,55), la mayor gravedad del asma (OR=3,11), la presencia de un evento estresante reciente (OR=2,44), una menor importancia otorgada al cumplimiento terapeutico (OR=1,66) y vivir en un medio rural (OR=1,29) fueron factores de riesgo para asma mal controlada. Por el contrario, el sexo, la edad, la obesidad, el tabaquismo, el consumo de alcohol y el nivel educacional no mostraron ninguna influencia sobre el control del asma. Conclusiones En Espana el asma permanece mal controlada, y algunos de los factores relacionados con esta situacion podrian ser modificables desde el sistema sanitario.

Introduction Asthma control has been found to be inadequate in all populations studied to date and accounts for the majority of costs for this disease. The objective of our study was to evaluate the prevalence of poorly-controlled asthma in primary care patients and to identify some of the factors associated with this situation. Methods We conducted a transversal study that included asthmatic patients over 18 years of age who were monitored in primary care visits (n = 2159). Asthma control was evaluated using the Asthma Control Questionnaire. The demographic variables and the adherence to therapy were evaluated using a questionnaire. The OR for poorly controlled asthma was calculated using logistic regression using asthma control as the dependent variable, which was assessed using the ACQ score. Results The prevalence of uncontrolled asthma was 63.8%. Risk factors for poorly-controlled asthma were treatment with oral corticosteroids (OR = 6.55), greater severity of asthma (OR = 3.11), the presence of a recent stressful event (OR = 2.44), a lesser importance given to compliance with therapy (OR = 1.66) and living in rural areas (OR = 1.29). In contrast, sex, age, obesity, smoking, alcohol consumption and educational level did not show any influence over asthma control. Conclusions Asthma remains poorly controlled in Spain but some of the factors related to this situation could be changed by the healthcare system.

Jewish women played a central symbolic and practical role in helping their persecuted communities maintain coherence and identity, but their non-normative leadership roles are rarely recognized. This article examines their little-known but essential contributions to the burgeoning economic life of Northern French cities from the twelfth to the fourteenth century. Although they usually made only small loans, they often collaborated with male Jewish money-lenders in short-lived, varying partnerships in order to make substantial loans to nobles, for marriages or financial emergencies. In some localities, they controlled as much as one-third of the loan business. They had few female Christian counterparts. Not generally more emancipated than Christian women, they nevertheless found in money-lending opportunities to assert autonomy not otherwise granted them by society.

Improved topsoil structural quality is expected under no-till farming, but soil physical constraints can develop under continuous no-till. Our objectives were: to evaluate the properties of loam, silty loam, and silty clay loam soils under various management practices on a regional scale; to clarify the relationship between soil organic matter pools and soil physical properties; and to find a minimum set of topsoil properties to characterize trends established by tillage. Thirty-nine loam, silty loam, and silry clay loam soils were sampled from cropped fields managed using conventional tillage (CT) and no-till (NT) as well as six undisturbed soils (uncropped). The A horizon thickness did not differ among soil textural groups and was 4 cm thicker in uncropped soils. Total and particulate organic C were significantly affected by management (uncropped > CT = NT, P < 0.001). Soil structural instability of uncropped soils (0.317 mm) differed from CT soils (0.723 mm) but not from NT soils (0.573 mm). Soil structural instability was negatively related to total and particulate organic C, and no relation was found with the resistant organic C pool. Water infiltration rate was the only topsoil properry affected by a significant texture x management interaction. Lower infiltration rates in NT silry soils were caused by plary structural forms with horizontal pores. Soil penetration resistance (0-5 cm) was 0.77 MPa higher in NT than in CT soils. A minimum set of topsoil properties to evaluate tillage management includes structural instability, total or particulate organic C, infiltration rate, and penetration resistance.

La respuesta inmune a la infección por Echinococcus granulosus en el ovino ha sido poco estudiada. El objetivo del presente trabajo fue aportar información sobre la fisiopatología y la respuesta inmune a la infección experimental con E. granulosus en ovinos. Se inocularon experimentalmente ovinos con tres dosis distintas de huevos de E. granulosus, evaluándose la repuesta inmune por seguimiento mediante enzimo inmuno ensayo con tres preparaciones antigénicas (líquido hidatídico total, fracción purificada de líquido hidatídico total y fracción lipoproteica purificada) durante 500 días. Se sacrificaron animales en forma escalonada para observar macroscópica y microscópicamente el desarrollo del parásito. La respuesta inmune se detectó a partir de los 10 días y se mantuvo durante el período de observación, resultando inicialmente proporcional a la carga de huevos inoculados, y disminuyendo las diferencias con el tiempo. Se identificaron quistes fértiles a los 10 meses post inoculación y oncósferas vivas 500 días post inoculación. La respuesta de anticuerpos en el ovino a la infección por E. granulosus fue anterior a la formación de líquido hidatídico y resultó generada por la movilidad de la oncósfera. La temprana fertilidad identificada histológicamente indica que la alimentación de canes con vísceras de ovinos jóvenes puede producir ciclos de infección. La presencia de oncósferas vivas en el hígado, por su parte, aporta información sobre la patogenia de la enfermedad y permite expresar hipótesis sobre las causas de nuevas operaciones en el hombre luego de la extirpación de un quiste hidatídico lo que podría liberar el freno inmunitario sobre dichas oncósferas.The immune response to Echinococcus granulosus in sheep has not been extensively investigated. The objective of this study was to increase the information on the physiopathology of E. granulosus and the immune response elicited in sheep. Animals were experimentally inoculated with three different doses of E. granulosus eggs and the immune response was evaluated over 500 days using enzyme immunoassay with three antigenic preparations: total hydatid fluid, purified fraction of hydatid fluid and purified lipoprotein fraction. Sheep were slaughtered at different intervals to observe the macroscopic and microscopic development of the parasite. Immune response was detected at 10 days and was maintained throughout the observation period, being initially proportional to the load of inoculated eggs and then decreasing over time. Fertile cysts were identified 10 months after inoculation and live onchosphere 500 days after inoculation. Antibody response to E. granulosus in sheep preceded hydatid fluid formation and was generated by the mobility of the onchosphere. Early histological identification of fertile cysts indicates that feeding dogs with viscera of young sheep can produce cycles of infection. Furthermore, the presence of live onchosphere in the liver here found contributes to a better knowledge of the pathogenesis of this disease it could be hypothetically considered as a cause for the repeated surgeries necessary in man after the extirpation of a hydatid cyst.

Decreasing P buffer capacity of the soil surface in no-tilled soils has been attributed to enrichment of both P and OM (OM). As soil surface enrichment with P and OM usually occurs simultaneously in no-tilled soils, it is not clearly established whether the increase of soil OM affects the capacity of soils to retain P. A study was conducted to assess whether the variations in soil OM (total and particulate) at soil surface affects P retention capacity. Thirty five soils from the Rolling Pampa (17 tilled and 18 no-tilled) were selected. All soils had medium to low levels of available P (P Bray1 53 μm), particle size distribution, and pH. Tilled and no-tilled soils did not differ in soil texture, pH, total and available P content. On the contrary, no-tilled soils had more OM (+14%) and POM (+56%) than tilled soils. The capacity of soils to retain added P was not different in both groups of soils. Phosphorus sorption index was not related to soil content of total OM or POM. Variation in P sorption index was only related to soil clay content (r 2 = 0.44). This study provides evidence contradicting the long held assumption that the reported decrease in P sorption at the surface of no-tilled soils was caused in part by OM enrichment.

Maize root growth is negatively affected by compacted layers in the surface (e.g. agricultural traffic) and subsoil layers (e.g. claypans). Both kinds of soil mechanical impedances often coexist in maize fields, but the combined effects on root growth have seldom been studied. Soil physical properties and maize root abundance were determined in three different soils of the Rolling Pampa of Argentina, in conventionally-tilled (CT) and zero-tilled (ZT) fields cultivated with maize. In the soil with a light Bt horizon (loamy Typic Argiudoll, Chivilcoy site), induced plough pans were detected in CT plots at a depth of 0-0.12 m through significant increases in bulk density (1.15 to 1.27 Mg m-3) and cone (tip angle of 60 º) penetrometer resistance (7.18 to 9.37 MPa in summer from ZT to CT, respectively). This caused a reduction in maize root abundance of 40-80 % in CT compared to ZT plots below the induced pans. Two of the studied soils had hard-structured Bt horizons (clay pans), but in only one of them (silty clay loam Abruptic Argiudoll, Villa Lía site) the expected penetrometer resistance increases (up to 9 MPa) were observed with depth. In the other clay pan soil (silty clay loam Vertic Argiudoll, Pérez Millán site), penetrometer resistance did not increase with depth but reached 14.5 MPa at 0.075 and 0.2 m depth in CT and ZT plots, respectively. However, maize root abundance was stratified in the first 0.2 m at the Villa Lía and Pérez Millán sites. There, the hard Bt horizons did not represent an absolute but a relative mechanical impedance to maize roots, by the observed root clumping through desiccation cracks. O crescimento das raízes do milho é alterado negativamente quando o solo apresenta camadas compactadas superficiais (trânsito de maquinário) ou subsuperficiais (camada argilosa). Os dois tipos de impedimentos mecânicos muitas vezes coexistem nos campos sob cultura de milho, porém seus efeitos combinados no crescimento das raízes do milho foram raramente estudados. As propriedades físicas do solo e a abundância de raízes de milho foram estudadas em três diferentes solos da região do Pampa Ondulado, na Argentina, que foram cultivados em parcelas próximas com milho em preparo convencional e em plantio direto. No solo com um horizonte Bt incipiente (Argiudol típico franco, local Chivilcoy), as compactações induzidas pelo preparo foram identificadas nas parcelas sob preparo convencional na profundidade de 0-12 cm por meio de significativos incrementos na densidade aparente (1,15 e 1,27 Mg m-3) e na resistência à penetração com penetrômetro de cone (ponta com ângulo de 60° ), com valores de 9,37 e 7,18 MPa, no verão, nas parcelas sob preparo convencional e plantio direto, respectivamente. Isso ocasionou diminuição da abundância nas raízes do milho entre 40 e 80 % sob preparo convencional, se comparado com plantio direto, abaixo das compactações induzidas. Dois dos solos estudados tinham horizontes Bt fortemente estruturados, porém somente um deles (o Argiudol abrúptico franco-argilo-siltoso, localizado em Villa Lia) apresentou os incrementos na resistência à penetração esperados (até 9 MPa) em profundidade. No outro solo com camada argilosa compactada (Argiudol vértico franco-argilo-siltoso, de Pérez Millán), a resistência à penetração não aumentou com a profundidade, mas atingiu 14,5 MPa a 0,075 e 0,2 m de profundidade para o plantio convencional e o plantio direto, respectivamente. Todavia, a abundância das raízes de milho foi estratificada dentro dos primeiros 0,2 m nos locais Villa Lia e Pérez Millán. Assim, os horizontes Bt bem desenvolvidos não representaram um impedimento mecânico absoluto para a penetração das raízes do milho, e sim um impedimento relativo, já que foram localizadas raízes que penetraram pelas fendas ocasionadas por ciclos de umedecimento e secagem.

Nitrogen (N) management may be improved by a thorough understanding of the nutrient dynamics during previous‐crop residue decomposition and its impact on fertilizer N fate in the soil–plant system. An experiment was conducted in the Argentine Pampas to evaluate the effect of maize and soybean as previouscrops and plow‐till and no‐till methods on N dynamics and 15N‐labeled fertilizer uptake during a wheat growing season. Maize and soybean residues released N under both tillage treatments, but N release was faster from soybean residues and when residues were buried by tillage. Net immobilization of N on decomposing residues was not detected. A regression model that accounted for 92% of remaining N variability included time, previous crop, and tillage treatment as independent variables. The rapid residue decomposition with N release was attributed to the high temperatures of the agroecosystem. The recovery of 15N‐labeled fertilizer in the wheat crop, soil organic matter, and decomposing residues was...

Introduccion y objetivos La carga de enfermedad coronaria atribuible a los factores de riesgo cardiovascular en Espana ha sido extrapolada tradicionalmente de otras poblaciones. Este estudio pretende estimar el riesgo coronario atribuible al tabaquismo, la hipercolesterolemia, la hipertension, la diabetes y el sobrepeso, utilizando datos procedentes de poblaciones Espanolas. Metodos Las prevalencias de los factores de riesgo en la poblacion general se obtuvieron de un metaanalisis de 48 estudios transversales realizados en Espana, y las prevalencias en enfermos coronarios se tomaron de los registros hospitalarios multicentricos PRIAMHO II y PREVESE II. Los riesgos relativos brutos y ajustados de enfermedad coronaria se obtuvieron del seguimiento durante 5 anos de una cohorte de atencion primaria de 6.124 personas adultas libres de enfermedad cardiovascular. Las fracciones atribuibles brutas y ajustadas se calcularon para ambos sexos y para varones y mujeres por separado. Resultados En los varones, el 42,5% (intervalo de confianza [IC] del 95%, 6,8%-59,6%) de la incidencia ajustada de enfermedad coronaria se atribuyo al sobrepeso; el 33,9% (IC del 95%, 22,6%-41%), al tabaquismo, el 19,4% (IC del 95%, 8,2%-26,5%), a la hipercolesterolemia, y el 15,5% (IC del 95%, 1,6%-24,6%), a la hipertension. En las mujeres, el 36,5% (IC del 95%, –8%-56,3%) de los casos de cardiopatia isquemica se atribuyeron al sobrepeso, el 24,8% (IC del 95%, 12%-31,9%), a la diabetes y el 20,1% (IC del 95%, 6,1%-28,6%), a la hipercolesterolemia. Conclusiones El sobrepeso y el tabaquismo en varones son los factores de riesgo cardiovascular a los que cabe atribuir un mayor impacto poblacional en la enfermedad coronaria.

La pancreatitis aguda puede tener una evolucion muy variable. La mortalidad de las formas graves supera el 20% en la mayoria de los pacientes como consecuencia de la sepsis o el fallo multiorganico1-3. La necrosis y el absceso pancreatico son complicaciones muy graves, con un tratamiento quirurgico que se asocia a una importantisima morbimortalidad, pero con curso evolutivo fatal si no lo recibe. Todos los autores estan de acuerdo en el desbridamiento del absceso pancreatico, pero permanece todavia en debate el tipo de drenaje empleado4,5. Presentamos el caso clinico de una mujer de 79 anos de edad con el antecedente clinico de una pancreatitis aguda necrosante, que acude a urgencias por dolor abdominal localizado en vacio y region lumbar izquierda, nauseas y sindrome febril de 1 semana Cartas al director

El sindrome de distres respiratorio del adulto (SDRA) es una complicacion infrecuente de la cetoacidosis diabetica que aumenta notablemente su mortalidad. Su patogenia es probablemente multifactorial. Se han propuesto como mecanismos el descenso brusco de la presion osmotica y las alteraciones hidroelectroliticas que ocurren durante el tratamiento, en especial la hipofosfatemia. Presentamos el caso de un varon de mediana edad que desarrollo un SDRA durante el tratamiento de un episodio de cetoacidosis.

The knowledge of nitrogen (N) losses in direct‐drilling agrosystems is essential to develop strategies to increase fertilizer efficiency and to minimize environmental damage. The objectives were i) to quantify the magnitude of N volatilization and leaching simultaneously as affected by different urea fertilization rates and ii) to evaluate the capacity of these specific plant–soil systems to act as a buffer to prevent nitrate leaching. Two experiments were conducted during 2001/02 and 2002/03 growing seasons in Alberti, Argentina. The crop was direct‐drilled maize and the soil a Typic Argiudoll. Ammonia losses, N uptake by crop at flowering and harvest, grain yield, N in previous crop residues, and soil nitrate content up to 2‐m depths were determined. Nitrogen availability, soil nitrate (NO3)‐N up to 1 m plus fertilizer N, was linearly and highly associated with crop N uptake at flowering (R2=0.93, P

Melatonin is synthesized in peripheral locations of vertebrates, including the gastrointestinal tract (GIT). In teleost, information regarding this topic is scarce. Here we studied the presence and synthesis of melatonin at the rainbow trout GIT. Different sections of trout GIT (from esophagus to hindgut) were dissected out and assayed for contents of melatonin, serotonin (5-HT) and its metabolite, 5-hydroxyindole acetic acid, as well as for aanat1, aanat2 and hiomt mRNA abundance. A trout group was pinealectomized to evaluate changes in plasma and gut melatonin content. Finally, the daily profile of melatonin and 5-HT content, and aanat1, aanat2 and hiomt mRNA abundance were analyzed in gut of trout kept under normal lighting, and then under constant darkness. Melatonin was detected in all GIT regions with higher concentrations in the muscular wall than in the mucosa, a similar trend to that of 5-HT. In contrast, transcripts of melatonin synthesis enzymes were more abundant in the mucosa. Pinealectomy did not affect melatonin levels in midgut and hindgut either at day or at night. Additionally, no daily rhythms could be defined for melatonin content in gut tissues but increases during late light phase and at midnight occurred. However, aanat1, aanat2 and hiomt mRNA abundance showed clear daily rhythms with peaks at night. These rhythms remained with a 3-h phase advanced peak in fish exposed to constant darkness. Our results provide clear evidence for a local synthesis of melatonin in trout GIT that might be influenced by the content of 5-HT in the tissue. The process is affected by environmental light cycle and is likely to be under circadian regulation.

There is no evidence in fish brain demonstrating the existence of changes in lactate metabolism in response to alterations in glucose levels. We induced in rainbow trout through intraperitoneal (IP) treatments, hypoglycaemic or hyperglycaemic changes to assess the response of parameters involved in lactate metabolism in glucosensing areas like hypothalamus and hindbrain. To distinguish those effects from those induced by peripheral changes in the levels of metabolites or hormones, we also carried out intracerebroventricular (ICV) treatments with 2-deoxy-D-glucose (2-DG, a non-metabolizable glucose analogue thus inducing local glucopenia) or glucose. Finally, we also incubated hypothalamus and hindbrain in vitro in the presence of increased glucose concentrations. The changes in glucose availability were in general correlated to changes in the amount of lactate in both areas. However, when we assessed in these areas the response of parameters related to lactate metabolism, the results obtained were contradictory. The increase in glucose levels did not produce in general the expected changes in those pathways with only a minor increase in their capacity of lactate production. The decrease in glucose levels was, however, more clearly related to a decreased capacity of the pathways involved in the production and use of lactate, and this was especially evident after ICV treatment with 2-DG in both areas. In conclusion, the present results while addressing the existence of changes in lactate metabolism after inducing changes in glucose levels in brain glucosensing areas only partially support the possible existence of an astrocyte-neuron lactate shuttle in hypothalamus and hindbrain of rainbow trout relating glucose availability to lactate production and use.

La realidad portuguesa forma parte del acervo temático del teatro español del Siglo de Oro, que destaca de los lusos su valor en la guerra y su exceso en la pasión. Las interacciones literarias se produjeron en dos sentidos: la tradición lusitana fue tratada en las piezas españolas, y los dramaturgos portugueses escribieron en castellano siguiendo a Lope de Vega en su Arte nuevo de hacer comedias en este tiempo (1609). Aunque la historia y la hagiografía serán las vertientes más explotadas debido a la repercusión de sus protagonistas, en otras ocasiones Portugal servirá de ambientación a conflictos universales. Reyes como don Afonso Henriques, don João II o don Sebastião protagonizan obras de Tirso de Molina, Lope de Vega o Cubillo de Aragón y, El príncipe constante de Calderón y Caer para levantar de Moreto, Cáncer y Matos Fragoso relatan, respectivamente, la vida de dos santos portugueses, S. Fernando y S. Gil. Analizaremos El príncipe constante y A secreto agravio, secreta venganza de Calderón y Las quinas de Portugal de Tirso de Molina para descubrir el grado de implicación existente entre los planteamientos dramatúrgicos y el contexto histórico que los incluye o propicia, para intentar desvelar las claves que motivaron el auge y el declive de los temas portugueses en el teatro español del siglo XVII. The Portuguese reality is part of the thematic heritage of the Spanish Golden Age theatre which highlights from the Lusitanian their courage at war and their excess in passion. Literary interactions took place in two senses: the Lusitanian tradition was treated in Spanish pieces, and Portuguese playwrights wrote in Castilian following Lope de Vega in his Arte nuevo de hacer comedias en este tiempo (1609). Although history and hagiography will be the most exploited aspects due to the impact of their protagonists, on other occasions Portugal will be used as a setting to universal conflicts. Kings such as Don Afonso Henriques, Don João II and Don Sebastião star in works of Tirso de Molina, Lope de Vega or Cubillo de Aragón; and El príncipe constante by Calderón and Caer para levantar by Moreto, Matos Fragoso and Cáncer relate, respectively, the lives of two Portuguese saints, S. Fernando and S. Gil. We will analyse El príncipe constante and A secreto agravio, secreta venganza by Calderón and Las quinas de Portugal by Tirso de Molina, with the aim of discovering the degree of involvement between the dramaturgical approaches and historical context that includes or propitiates them, in order to try to reveal the elements that motivated the rise and the decline of Portuguese topics in the seventeenth century Spanish theatre.

Los suelos manejados con siembra directa presentan valores de resistencia a la penetración y de densidad aparente en superficie mayores que los suelos laboreados. La utilización de descompactadores puede ser una alternativa para aliviar dicha compactación. Los objetivos del presente trabajo fueron: 1- evaluar el efecto de la descompactación en siembra directa sobre las algunas propiedades físicas del suelo a siembra y cosecha del cultivo de maíz; 2- determinar el efecto de la descompactación sobre el desarrollo de las raíces, el rendimiento del cultivo de maíz y sus componentes. Durante la campaña 2004/05 se llevaron a cabo tres experimentos en las localidades de Junín, San Gregorio y Chivilcoy. El diseño experimental fue de bloques completos con tres repeticiones. Los tratamientos evaluados fueron: testigo (siembra directa continua) y descompactado (pasaje de descompactador entre 36-42 cm de profundidad). A siembra y cosecha se determinó la densidad aparente, la humedad, la resistencia a la penetración y la infiltración. A floración se evaluó la abundancia radical, la radiación interceptada y el índice de verdor (SPAD). A cosecha se determinó el rendimiento y sus componentes. El tratamiento descompactado presentó un importante aumento de la tasa de infiltración a la siembra (PNo-tilled soils have higher penetration resistances and bulk density values than tilled soils. Shallow compaction may be alleviated using deep tillage practices. The objectives of this study were to determine the effects of soil alleviation on: 1- soil physical properties at maize sowing and harvest, 2- root abundance, maize yield and its components. Three experiments were conducted during the 2004/05 growing season. The experiments had a complete block design, with 2 treatments (control and deep-tilled) and 3 replicates, and were located at Junín, San Gregorio and Chivilcoy. Soil bulk density, soil water content, soil penetration resistance and infiltration rate were determined at maize sowing and harvest. At flowering maize root abundance, intercepted photosynthetic active radiation and leaf greenness were determined. Additionally, yield and its components were measured. Soil alleviation increased infiltration rate at sowing (P

The central pattern generator for locomotion in vertebrates is composed of different spinal neuronal populations that generate locomotor movement. In the lamprey spinal cord, several classes of interneurons have been identified based on morphologic and physiological criteria and integrated in the spinal cord circuits implicated in the generation of locomotion. However, the lack of histochemical markers for most of the interneurons makes it difficult to study whole populations along the spinal cord. We have investigated the immunoreactivity with antibodies raised against calbindin and calretinin. Several types of neurons could be classified: (1). strongly immunoreactive neurons located dorsomedially, (2). moderately immunoreactive neurons located laterally, (3). small weakly immunoreactive neurons, d). ventromedial neurons, (4). liquor contacting cells, and (5). motoneurons. The ventromedial group of calbindin-immunoreactive neurons also is immunoreactive for serotonin and, therefore, represents the ventromedial group of dopamine/serotonin spinal neurons. Some of the lateral calbindin-immunoreactive neurons may be CC-type cells (cells with caudal-crossed axons), because they are retrogradely labeled by tracer injections into the contralateral spinal cord. Other well-characterized cell types, such as sensory dorsal cells, lateral interneurons, descending propriospinal edge cells, and spinobulbar giant interneurons are negative for both calbindin and calretinin. Therefore, calbindin and calretinin are useful markers for the study of cell populations that may be integrated in locomotor circuits.

The Rolling and Flat Pampas are vast plains located in Argentina. Wheat is one of the most economically important crops of these regions. Two extensive studies have been preformed to evaluate the effects of nitrogen fertilization on wheat yield at field scale. We pooled these published data to establish relationships between wheat yield and soil and climate variables under a wide range of soils and management conditions. Total soil carbon was the variable more associated with yield (r 2=0.25). The increase in grain production expected between soils with low and high carbon levels rounded 2,200 kg ha− 1. A multivariate model which included carbon in the light fraction, potential mineralizaable nitrogen, available mineral nitrogen, and rainfall was obtained, explaining 50% of wheat yield variability. These results highlight the importance of organic matter on grain production in the Humid Pampas. This effect can be due to the role of organic soil components as source of nutrients for crops.

Our objectives were to quantify the effect of abiotic factors on CO2 emissions in the Humid Pampa of Argentina and estimate the potential increase in CO2 fluxes from this agricultural soil as a consequence of climate change. The experimental site was located at Pergamino (33°56′S, 60°34′W), on a fine, illitic, thermic Typic Argiudoll soil. In situ CO2 production presented an exponential relationship with air temperature. C liberated annually by mineralization was estimated by integration of monthly respiration measurements and amounted to 8.4 t C ha–1 year–1. Future monthly CO2 fluxes were calculated for the climate change scenario (doubled atmospheric C concentration) using mean monthly temperatures predicted for Pergamino. An increase of around 50% in CO2 emission from agricultural soils in the Humid Pampa could be expected as a consequence of climate change. The effect of the climate change scenario projected by the global climate models for the Humid Pampa indicates a reduction of the biomass production of cereal crops. Consequently, the predicted decrease in C inputs to soil for this region and an important increase in soil C mineralization would result in marked future C losses.

Carbon dioxide emission from soil plays an important role in the global carbon cycle. Short term losses of soil carbon due to tillage are of a variable magnitude. Our objective was to evaluate the effect of plowing the soil on CO2-C emissions during summer in a coarse-loamy mixed thermic Typic Hapludoll from the Argentine Rolling Pampa. Temperature after tillage was higher in the plowed soil than under no-tillage, being higher the soil water content in the later treatment. Plowing the soil did not produce an immediately impact on soil surface CO2-C emission, but induced an important CO2-C flush few days later. A difference of 16 up to 25 kg C ha–1 d–1 in the CO2-C emissions was observed from the second up to the fourth sampling dates after tillage. Difference in total CO2-C emissions between the plowed soil and the no-tillage treatment was 580 kg C ha–1, during the 40 days measurement period. This difference in CO2-C emission was partitioned between residue decomposition and humus mineralization. Carbon mineralized from humus was 270 kg C ha–1 higher under plow tillage than under no tillage. This figure represented an important extra loss of 0.48% of the soil organic carbon content from the 0–30 cm depth, as consequence of plowing in the warmest season of the year.

The Rolling and Flat Pampas are vast plains which contribute with more than half of the Argentine wheat production. In the 80's three extensive studies were preformed in these regions, which determined nitrate content in the 0–20, 20–40, and 40–60 cm soil layers, comprising a wide range of soil, climatic and cultural variables. More recently, we determined the mineral-N (N) content at 0–30 and 30–60 cm depths, in a set of farmer's plots under different tillage systems and previous crop. These datasets were used in order to establish simple equations to predict N availability in the 0–60 cm stratum, from the N availability in the upper layer. Nitrate content at wheat presowing time presented a clear stratification pattern with depth. For the fist dataset, strong relationships were obtained between the nitrate content at different soil depths, with previous crops of corn, sunflower or sorghum (R2=0.52 to 0.90, P

Conservation tillage, and especially no-tillage, induce changes in the distribution of organic pools in the soil profile. In long-term field experiments, marked stratification of the total soil microbial biomass and its activity have been observed as consequence of the application of no-tillage to previously tilled soils. Our objective was to study the evolution of the total and active soil microbial biomass and mineralized C in vitro during the first crop after the introduction of no-tillage to an agricultural soil. The experiment was performed on a Typic Hapludoll from the Argentinean Pampa. Remaining plant residues, total and active microbial biomass and mineralized C were determined at 0–5 cm and 5–15 cm depths, at three sampling times: wheat tilling, silking and maturity. The introduction of no-tillage produced an accumulation of plant residues in the soil surface layer (0–5 cm), showing stratification with depth at all sampling dates. Active microbial biomass and C mineralization were higher under no-tillage than under conventional tillage in the top 5 cm of the profile. The total soil microbial biomass did not differ between treatments. The active soil biomass was highly and positive correlated with plant residues (r 2=0.617;P

Changing conventional tillage to conservation tillage systems affects nitrogen (N) cycling in agroecosystems. Our objective was to evaluate the role of soil organic pools, specially plant residues, as sources‐sinks of nitrogen in an humid and warm temperate environment cropped to wheat, under plow‐ and no‐tillage. The experimental site was in the Argentine Pampa on a Typic Hapludoll. A balance‐sheet method was used: Nupt+Nres=Nsow+Nmin, where Nupt=N uptake by the crop at harvest; Nsow=soil mineral N as NH4 and NO3 at 0–90 cm depth, one month before sowing, plus N added as fertilizer; Nres=residual soil mineral N as NH4 and NO3 at 0–90 cm depth, at harvest; Nmin=N mineralized from humus and plant residues during wheat growing period. Nupt did not differ between tillage systems. Nitrogen supply by the mineral N pool, estimated by the difference Nsow‐Nres, was ca. 150 kg N ha‐1 in both tillage systems. Plant residues decomposed and released N under both treatments. This organic N pool decreased 77% ...

The labile component of soil organic matter (SOM) plays an important role in short-term nutrient turnover. Our objectives were (i) to establish the relationships between carbon in soil density fractions with carbon mineralization and the microbial biomass under contrasting conditions, (it) to compare the goodness of fit of different mathematical models to describe carbon mineralization, and (iii) to evaluate the relationships of the SOM pools and the mineralization parameters estimated by the best kinetic model. Twenty-eight soil samples were collected from a fine, illitic, thermic Typic Argiudoll localized in Argentina. These samples differed in the soil management (pasture and agriculture), tillage systems (chisel tillage, plough tillage, and no-tillage), crop rotation, or depths. Microbial biomass was highly correlated with total carbon (r 2 = 0.777, P 2.0 g mL -1 ) soil fractions. Carbon in the soil light fraction was strongly related to the carbon mineralized at 10 and 160 d of incubation. The exponential and hyperbolic models showed a good description of the mineralization data (r 2 >0.982). The application of models which considered two organic matter pools could not describe the mineralization of some samples. The hyperbolic model estimated higher potentially carbon mineralizable pools (C 0 ) and semidecomposition time periods than the exponential one. The C 0 estimated by the exponential model were similar to the carbon content in the soil light fraction. This soil organic component seemed to be the driving variable of microbial activity and a good predictor of soil potential carbon mineralization.

Substernal multinodular goiter is a common entity that may cause life threatening pressure symptoms. We report the case of a patient with tracheal stenosis due to multinodular goiter and discuss various treatment options.

Los adenomas hipofisarios son tumores con un comportamiento generalmente benigno aunque en alrededor del 9 al 40% de los casos invaden estructuras vecinas. La extension hacia los senos cavernosos de los adenomas hipofisarios puede producir una compresion de las estructuras que alberga, como los pares craneales oculomotores (III, IV y VI) y la primera y la segunda rama del trigemino. La cefalea es un sintoma frecuente en los pacientes que presentan un adenoma hipofisario y puede estar producida por multiples causas. La neuralgia del trigemino como consecuencia de la compresion del nervio en su recorrido por el seno cavernoso es una causa rara de cefalea en estos pacientes, y es todavia mas infrecuente que este sea el unico sintoma que produzca un adenoma hipofisario. Presentamos el caso de una paciente con un macroprolactinoma que presento como sintoma una neuralgia del trigemino con una remision completa del dolor tras el tratamiento del adenoma con cabergolina.

The active pool of organic matter plays an essential role in the short-term of nutrients turnover in soil. An approach to characterizing this fraction is through densimetric techniques which isolate soil light fractions. Cropping and tillage systems are determinants of the amount and distribution of soil organic matter, especially in the upper layers of the soil profile. Our objectives were to evaluate the distribution and dynamics of carbon in different density fractions in order to provide a better understanding of soil fertility changes induced by contrasting types of soil management: plow tillage, no-tillage and pasture. The total and active microbial biomass pools and microbial activity were also determined. The experiment was performed on a Typic Argiudoll from the Argentinean Pampa. Organic carbon was highest under pasture, but there were no differences between the others two treatments for the 0–15 cm layer. Under the pasture and no-tillage treatments, organic carbon decreased with depth. The light fraction (density ≤1.6 g ml−1) was higher under no-tillage than in the plowed soil, indicating that this fraction was more sensitive to management than was total carbon. The carbon mineralized in 160 d of incubation from different density fractions followed the order: light fraction>medium fraction (1.6–2 g ml−1)>heavy fraction (≥2 g ml−1), presumably because of an increase in chemical and physical protection of organic matter in the heavier fractions. Total soil microbial biomass was stratified under the pasture and no-tillage treatments. Basal respiration was significantly associated with the availability of carbon in the light fraction (r2=0.98, P

Waterlogging frequently reduces plant biomass allocation to roots. This response may result in a variety of alterations in mineral nutrition, which range from a proportional lowering of whole-plant nutrient concentration as a result of unchanged uptake per unit of root biomass, to a maintenance of nutrient concentration by means of an increase in uptake per unit of root biomass. The first objective of this paper was to test these two alternative hypothetical responses. In a pot experiment, we evaluated how plant P concentration of Paspalum dilatatum, (a waterlogging-tolerant grass from the Flooding Pampa, Argentina) was affected by waterlogging and P supply and how this related to changes in root-shoot ratio. Under both soil P levels waterlogging reduced root-shoot ratios, but did not reduce P concentration. Thus, uptake of P per unit of root biomass increased under waterlogging. Our second objective was to test three non-exclusive hypotheses about potential mechanisms for this increase in P uptake. We hypothesized that the greater P uptake per unit of root biomass was a consequence of: (1) an increase in soil P availability induced by waterlogging; (2) a change in root morphology, and/or (3) an increase in the intrinsic uptake capacity of each unit of root biomass. To test these hypotheses we evaluated (1) changes in P availability induced by waterlogging; (2) specific root length of waterlogged and control plants, and (3) P uptake kinetics in excised roots from waterlogged and control plants. The results supported the three hypotheses. Soil P avail-ability was higher during waterlogging periods, roots of waterlogged plants showed a morphology more favorable to nutrient uptake (finer roots) and these roots showed a higher physiological capacity to absorb P. The results suggest that both soil and plant mechanisms contributed to compensate, in terms of P nutrition, for the reduction in allocation to root growth. The rapid transformation of the P uptake system is likely an advantage for plants inhabiting frequently flooded environments with low P fertility, like the Flooding Pampa. This advantage would be one of the reasons for the increased relative abundance of P. dilatatum in the community after waterlogging periods.

We studied the central projections of the mesencephalic nucleus of the trigeminal nerve (MesV) in the guppy (Lebistes reticulatus), after application of horseradish peroxidase or fluorescein dextran amine into the eye orbit. A small number (1 to 13) of large mesencephalic trigeminal neurons were solid labelled in the ipsilateral rostral mesencephalon. At the level of the trigeminal nerve entrance, the united process of each mesencephalic trigeminal cell bifurcates, giving rise to a peripheral branch that exits in the trigeminal nerve and a descending branch that runs caudally in a medial bundle separated from the descending trigeminal tract. This bundle passes close to the visceromotor nuclei of the medulla oblongata. Descending processes give rise to short collaterals to the descending nucleus of the trigeminus and the ventrolateral reticular area. Most MesV descending fibres terminate in this ventrolateral field at the transition of the medulla to the spinal cord, but one or two fibres could be followed to the C6 level, where they give rise to collaterals to the dorsal funicular nucleus. No collaterals directed to the trigeminal motor nucleus, the cerebellum, or the mesencephalic tegmentum were observed. These projections were also compared with those of the descending trigeminal tract.

Elasmobranchs possess a well-developed cerebellum with an associated cerebellar nucleus. To determine whether the organization of this nucleus is comparable with that of the deep cerebellar nuclei of mammals, we studied the dogfish cerebellar nucleus with light microscopic methods (Nissl stain, Golgi method, reduced silver stain, NADPH-diaphorase histochemistry and immunocytochemistry) and with electron microscopy. We found the dogfish cerebellar nucleus to consist of about 1,050 large neurons, the ratio of Purkinje cells to cerebellar nucleus neurons being about 17:1. Immunocytochemistry showed large glutamatergic neurons in the main portions of the nucleus and small glutamate- and/or α-aminobutyric acid (GABA)-immunoreactive cells in the subventricular region of the nucleus. Large glutamatergic neurons corresponded to bipolar or triangular cells revealed by Golgi methods. Application of horseradish peroxidase to the cerebellar cortex produced the labelling of beaded fibres of Purkinje cells in the cerebellar nucleus. Unlike in mammals, GABAergic innervation of the cerebellar nucleus was scarce: Purkinje cell axon terminals in the cerebellar nucleus did not appear to be GABA-immunoreactive, most GABAergic fibres being found in the subventricular neuropile. Some fibres immunoreactive to serotonin and somatostatin were also observed in the subventricular neuropile of the cerebellar nucleus. Three neuron types were distinguished with electron microscopy (types A to C). Type A cells were abundant and smooth-surfaced, and appeared to correspond to Golgi-impregnated neurons and large glutamate-immunoreactive cells. Type B neurons were scarce and possessed dendrites covered by sessile or stalked spines. Type C neurons were small cells located mainly in the medialmost region of the nucleus and corresponded to subventricular glutamate- and GABA-immunoreactive cells. Six types of synaptic bouton were observed (types I to VI). The most abundant (type I boutons) made symmetrical contacts and appeared to correspond to Purkinje cell axons. Type I boutons were the only type observed on perikarya and initial axon segments of type A cells. Type IV and type V boutons made complex glomerular-like asymmetrical contacts with spines of type B cells. Type VI boutons appeared to correspond to peptidergic and/or monoaminergic axons. The functional significance of these results is discussed. © 1996 Wiley-Liss, Inc.

Lampreys, together with hagfishes, represent the sister group of gnathostome vertebrates. There is an increasing interest for comparing the forebrain organization observed in lampreys and gnathostomes to shed light on vertebrate brain evolution. Within the prosencephalon, there is now a general agreement on the major subdivisions of the lamprey diencephalon; however, the organization of the telencephalon, and particularly its pallial subdivisions, is still a matter of controversy. In this study, recent progress on the development and organization of the lamprey telencephalon is reviewed, with particular emphasis on the GABA immunoreactive cell populations trying to understand their putative origin. First, we describe some early general cytoarchitectonic events by searching the classical literature as well as our collection of embryonic and prolarval series of hematoxylin-stained sections. Then, we comment on the cell proliferation activity throughout the larval period, followed by a detailed description of the early events on the development of the telencephalic GABAergic system. In this context, lampreys apparently do not possess the same molecularly distinct subdivisions of the gnathostome basal telencephalon because of the absence of a Nkx2.1-expressing domain in the developing subpallium; a fact that has been related to the absence of a medial ganglionic eminence as well as of its derived nucleus in gnathostomes, the pallidum. Therefore, these data raise interesting questions such as whether or not a different mechanism to specify telencephalic GABAergic neurons exists in lampreys or what are their migration pathways. Finally, we summarize the organization of the adult lamprey telencephalon by analyzing the main proposed conceptions, including the available data on the expression pattern of some developmental regulatory genes which are of importance for building its adult shape.