The Roles of Protocols and Protocolization in Improving Outcome From Severe Traumatic Brain Injury.

BACKGROUND AND OBJECTIVES: Our Phase-I parallel-cohort study suggested that managing severe traumatic brain injury (sTBI) in the absence of intracranial pressure (ICP) monitoring using an ad hoc Imaging and Clinical Examination (ICE) treatment protocol was associated with superior outcome vs nonprotocolized management but could not differentiate the influence of protocolization from that of the specific protocol. Phase II investigates whether adopting the Consensus REVised Imaging and Clinical Examination (CREVICE) protocol improved outcome directly or indirectly via protocolization. METHODS: We performed a Phase-II sequential parallel-cohort study examining adoption of the CREVICE protocol from no protocol vs a previous protocol in patients with sTBI older than 13 years presenting ≤24 hours after injury. Primary outcome was prespecified 6-month recovery. The study was done mostly at public South American centers managing sTBI without ICP monitoring. Fourteen Phase-I nonprotocol centers and 5 Phase-I protocol centers adopted CREVICE. Data were analyzed using generalized estimating equation regression adjusting for demographic imbalances. RESULTS: A total of 501 patients (86% male, mean age 35.4 years) enrolled; 81% had 6 months of follow-up. Adopting CREVICE from no protocol was associated with significantly superior results for overall 6-month extended Glasgow Outcome Score (GOSE) (protocol effect = 0.53 [0.11, 0.95], P = .013), mortality (36% vs 21%, HR = 0.59 [0.46, 0.76], P < .001), and orientation (Galveston Orientation and Amnesia Test discharge protocol effect = 10.9 [6.0, 15.8], P < .001, 6-month protocol effect = 11.4 [4.1, 18.6], P < .005). Adopting CREVICE from ICE was associated with significant benefits to GOSE (protocol effect = 0.51 [0.04, 0.98], P = .033), 6-month mortality (25% vs 18%, HR = 0.55 [0.39, 0.77], P < .001), and orientation (Galveston Orientation and Amnesia Test 6-month protocol effect = 9.2 [3.6, 14.7], P = .004). Comparing both groups using CREVICE, those who had used ICE previously had significantly better GOSE (protocol effect = 1.15 [0.09, 2.20], P = .033). CONCLUSION: Centers managing adult sTBI without ICP monitoring should strongly consider protocolization through adopting/adapting the CREVICE protocol. Protocolization is indirectly supported at sTBI centers regardless of resource availability.

Testing the Impact of Protocolized Care of Patients With Severe Traumatic Brain Injury Without Intracranial Pressure Monitoring: The Imaging and Clinical Examination Protocol.

BACKGROUND: Most patients with severe traumatic brain injury (sTBI) in low- or-middle-income countries and surprisingly many in high-income countries are managed without intracranial pressure (ICP) monitoring. The impact of the first published protocol (Imaging and Clinical Examination [ICE] protocol) is untested against nonprotocol management. OBJECTIVE: To determine whether patients treated in intensive care units (ICUs) using the ICE protocol have lower mortality and better neurobehavioral functioning than those treated in ICUs using no protocol. METHODS: This study involved nineteen mostly public South American hospitals. This is a prospective cohort study, enrolling patients older than 13 years with sTBI presenting within 24 h of injury (January 2014-July 2015) with 6-mo postinjury follow-up. Five hospitals treated all sTBI cases using the ICE protocol; 14 used no protocol. Primary outcome was prespecified composite of mortality, orientation, functional outcome, and neuropsychological measures. RESULTS: A total of 414 patients (89% male, mean age 34.8 years) enrolled; 81% had 6 months of follow-up. All participants included in composite outcome analysis: average percentile (SD) = 46.8 (24.0) nonprotocol, 56.9 (24.5) protocol. Generalized estimating equation (GEE) used to account for center effects (confounder-adjusted difference [95% CI] = 12.2 [4.6, 19.8], P = .002). Kaplan-Meier 6-month mortality (95% CI) = 36% (30%, 43%) nonprotocol, 25% (19%, 31%) protocol (GEE and confounder-adjusted hazard ratio [95% CI] = .69 [.43, 1.10], P = .118). Six-month Extended Glasgow Outcome Scale for 332 participants: average Extended Glasgow Outcome Scale score (SD) = 3.6 (2.6) nonprotocol, 4.7 (2.8) protocol (GEE and confounder-adjusted and lost to follow-up-adjusted difference [95% CI] = 1.36 [.55, 2.17], P = .001). CONCLUSION: ICUs managing patients with sTBI using the ICE protocol had better functional outcome than those not using a protocol. ICUs treating patients with sTBI without ICP monitoring should consider protocolization. The ICE protocol, tested here and previously, is 1 option.

Programas de Intervención Socioeducativos para Personas con Discapacidad Intelectual: una Revisión Sistemática / Social-Educational Intervention Programmes for People with Intelectual Disabilities: a Systematic Review

RESUMEN: El enfoque de la inclusión social y educativa cobra cada vez mayor relevancia en políticas dirigidas a personas en situación de discapacidad, especialmente cuando sus derechos demandan apoyos desde una perspectiva ecológica y multidimensional. De esta forma, el objetivo de esta revisión sistemática ha sido analizar la investigación relacionada con programas de intervención socioeducativos para niños, jóvenes y adultos con discapacidad intelectual que han seguido métodos experimentales y/o cuasi experimentales. De acuerdo con los lineamientos de la Declaración PRISMA se han seleccionado 19 estudios utilizando bases de datos internacionales, durante el periodo 1995-2020. Los resultados muestran que la mayor cantidad de programas consideran en su muestra, niños y adolescentes (68%) y en menor porcentaje a jóvenes y adultos (31%). Por otro lado, el 52.6% no identifica diseño y tipo de muestra, y la medida más utilizada corresponde a pre y post test (78.9%). Se discuten hallazgos y conclusiones para la mejora de apoyos a las personas con discapacidad intelectual especialmente frente a la crisis sanitaria del COVID-19.

ABSTRACT: The approach to social and educational inclusion is becoming increasingly relevant in policies aimed at people with disabilities, especially when their rights demand support from an ecological and multidimensional perspective. Tus, the objective of this systematic review has been to analyze the investigations related to socio-educational intervention programs for children, youth and adults with intellectual disabilities that have followed experimental and/or quasi-experimental methods. In accordance with the PRISMA Declaration guidelines, 19 studies were selected using international databases, during the 1995-2020 period. The results show that the largest number of programs consider children and adolescents in their sample (68%) and, to a lesser extent, young people and adults (31%). However, 52.6% do not identify the design and type of sample, and the most used measure corresponds to the pre and post test (78.9%). Findings and conclusions are discussed in order to improve support for people with intellectual disabilities, especially in the face of the health crisis of COVID-19.

Pesticide Sorption to Soilless Media Components Used for Ornamental Plant Production and Aluminum Water Treatment Residuals.

Commercial producers of containerized ornamental plants almost exclusively use soilless media as the substrate for growing the plants. Soilless media are composed primarily of organic materials as opposed to mineral soils. Significant amounts of pesticides can leach from pots containing soilless media to which pesticides have been added as drenches or top-dressings. One of the goals of this project was to identify whether individual components comprising soilless media have differing affinities for the pesticides acephate, imidacloprid, metalaxyl, and plant growth regulator paclobutrazol. One-point 24 h equilibrium sorption assays were conducted to characterize sorption of the pesticides to sand, perlite, vermiculite, coir, peat, pine bark, and aluminum-water treatment residuals (Al-WTRs). Five-point isotherms were then constructed for the more sorptive peat and pine bark substrate components, and for the Al-WTRs. Results indicated significant differences in pesticide behavior with each substrate. Sorption of acephate to most of the substrate components was relatively low, comprising 21-31% of the initial amounts for soilless media components and 63% in Al-WTRs. Al-WTRs were highly sorptive for imidacloprid as evidenced by a partition coefficient of K F = 3275.4 L kg-1. Pine bark was the most sorptive for metalaxyl-M with a measured K F = 195.0 L kg-1. Peat had the highest affinity for paclobutrazol (K F = 398.4 L kg-1). These results indicate that none of component of soilless media has a universally high attraction for all of the pesticides studied.

Imidacloprid soil movement under micro-sprinkler irrigation and soil-drench applications to control Asian citrus psyllid (ACP) and citrus leafminer (CLM).

Imidacloprid (IM) is used to control the Asian Citrus Psyllid (ACP) and citrus leafminer (CLM), which are related to the spread of huanglongbing (HLB or citrus greening) and citrus canker diseases, respectively. In Florida citrus, imidacloprid is mainly soil-drenched around the trees for proper root uptake and translocation into plant canopy to impact ACP and CLM. The objective of this study was to determine the effect of imidacloprid rate, and irrigate amount on concentration of imidacloprid in the soil following drench application to citrus trees in three age classes. The plots were established at the Southwest Florida Research and Education Center, Immokalee, using a randomized complete-block design for three age classes of trees: one-year-old trees (B1), three to five-year-old trees (B2), and eight-year-old trees (B3). The treatments were a combination of two rates each of imidacloprid (1D, 2D) and micro-sprinkling irrigation (1I, 2I). Imidacloprid and bromide (Br-) used as tracer were applied simultaneously. Soil moisture and concentrations of imidacloprid and Br were monitored using soil cores from hand held augers. Soil moisture content (θV) did not differ under two irrigation rates at any given observation day or depth, except following heavy rainfall events. Br- was lost from the observation depths (0-45 cm) about two weeks after soil-drench. Contrarily, imidacloprid persisted for a much longer time (4-8 weeks) at all soil depths, regardless of treatment combinations. The higher retardation of imidacloprid was related to the predominantly unsaturated conditions of the soil (which in turn reduced soil hydraulic conductivities by orders of magnitude), the imidacloprid sorption on soil organic matter, and the citrus root uptake. Findings of this study are important for citrus growers coping with the citrus greening and citrus canker diseases because they suggest that imidacloprid soil drenches can still be an effective control measure of ACP and CLM, and the potential for imidacloprid leaching to groundwater is minimal.

Metástasis a duodeno de cáncer renal de células claras con patrón sarcomatoide: reporte de caso / Duodenal metastases from sarcomatoid renal cell carcinoma: Case report

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Imidacloprid transport and sorption nonequilibrium in single and multilayered columns of Immokalee fine sand.

Imidacloprid (IMD) is a neonicotinoid pesticide soil-drenched to many crops to control piercing-sucking insects such as the Asian citrus psyllid (ACP). Neonicotinoids are persistent in the environment and transport analyses are helpful estimate leaching potential from soils that could result in groundwater pollution. The objective of this study was to analyze IMD breakthrough under saturated water flow in soil columns packed with three horizons (A, E, Bh) of Immokalee Fine Sand (IFS). Also, we used the dimensionless form of the convective-dispersive model (CD-Model) to compare the optimized transport parameters from each column experiment (retardation factor, R; fraction of instantaneous-to-total retardation, ß; and mass transfer coefficient, ω) with the parameters obtained from sorption batch equilibria and sorption kinetics. The tracer (Cl-) breakthrough curves (BTCs) were symmetrical and properly described by the CD-Model. IMD BTCs from A, Bh, and multilayered [A+E+Bh] soil columns showed steep fronts and tailing that were well described by the one-site nonequilibrium (OSNE) model, which was an evidence of non-ideal transport due to IMD mass transfer into the soil organic matter. In general, IMD was weakly-sorbed in the A and Bh horizons (R values of 3.72 ± 0.04 and 3.08 ± 0.07, respectively), and almost no retardation was observed in the E horizon (R = 1.20 ± 0.02) due to its low organic matter content (0.3%). Using the HYDRUS-1D package, optimized parameters (R, ß, ω) from the individual columns successfully simulated IMD transport in a multilayered column mimicking an IFS soil profile. These column studies and corresponding simulations agreed with previous findings from batch sorption equilibria and kinetics experiments, where IMD showed one-site kinetic mass transfer between soil surfaces and soil solution. Ideally, sandy soils should be maintained unsaturated by crop irrigation systems and rainfall monitoring during and after soil-drench application. The unsaturated soil will increase IMD retardation factors and residence time for plant uptake, lowering leaching potential from soil layers with low sorption capacity, such as the E horizon.

Imidacloprid Extraction from Citrus Leaves and Analysis by Liquid Chromatography-Mass Spectrometry (HPLC-MS/MS).

A procedure was developed to extract Imidacloprid (IMD) from newly-flushed and fully-expanded citrus leaves. The extraction was conducted in a bullet blender, using a small sample mass (0.5 g of fresh tissue), stainless-steel beads (24 g), and methanol as extractant (10 mL). The extracts did not require further clean-up before analysis by HPLC-MS/MS. The method was validated with control samples from IMD-untreated Hamlin orange trees. The method limit of detection and limit of quantitation were 0.04 and 0.12 µg g(-1), respectively. IMD recoveries from fortified leaf tissue were between 92 % and 102 %, with relative standard deviations of <8 %. The method was further evaluated by extracting leaves from Hamlin orange trees treated with IMD. The treated trees showed maximum concentrations of 10.8 and 21.8 µg g(-1), observed at 20 days after applying two soil-drenching rates (0.51 and 1.02 kg IMD ha(-1)), respectively. This extraction technique will generate useful data on IMD plant uptake, foliar concentration, and correlations with Asian citrus psyllid (ACP) mortality or control. The method could be used to generate baseline data to improve IMD soil-drenching applications as the main management practice to control the ACP.

Imidacloprid sorption kinetics, equilibria, and degradation in sandy soils of Florida.

Imidacloprid (IMD) is a neonicotinoid insecticide soil-drenched on sandy soils of southwest Florida for the control of Diaphorina citri Kuwayama or Asian citrus psyllid (ACP). The ACP vectors causal pathogens of a devastating citrus disease called citrus greening. Understanding the behavior of IMD in these soils and plants is critical to its performance against target pests. Samples from Immokalee fine sand (IFS) were used for sorption kinetics and equilibria experiments. IMD kinetics data were described by the one-site mass transfer (OSMT) model and reached equilibrium between 6 and 12 h. Batch equilibrium and degradation studies revealed that IMD was weakly sorbed (K(OC) = 163-230) and persistent, with a half-life of 1.0-2.6 years. Consequently, IMD has the potential to leach below the citrus root zone after the soil-drench applications.

La conducta adaptativa como criterio diagnóstico de discapacidad intelectual en estudiantes de Chile / Adaptative behavior as a diagnostic criterion of intellectual disability among students in Chile

Las políticas educativas en Chile han impulsado la evaluación de la conducta adaptativa como criterio de discapacidad intelectual, con el fin de establecer los apoyos requeridos por los estudiantes. Esta iniciativa es tan reciente como pionera y el artículo se propone evaluarla en relación con el marco normativo que regula y orienta las actividades profesionales vinculadas a ella.El trabajo realiza una revisión documental del contexto científico de la evaluación de la conducta adaptativa, analiza la coherencia entre dicho contexto y la política educativa chilena y elabora algunas sugerencias para el mejoramiento de la política y el desarrollo de capacidades profesionales. Este último aspecto resulta de la identificación de ciertas limitaciones en el marco normativo así como de la insuficiencia de recursos humanos capacitados para su implementación.

The educational policies in Chile have impelled the evaluation of adaptative behavior as a criterion of intellectual disability, so as to establish the supports required by the students. This initiative is both recent and pioneering and the article aims at evaluating it in relation to the normative framework that regulates and orients the professional activities connected to it. The work involves a documentary revision of the scientific context of the evaluation of adaptative behavior; it analyzes the coherence between said context and the Chilean educational policy and it presents some suggestions for improving the policies and the development of professional capacities. The latter aspect results from the identification of certain limitations in the normative framework as well as from the scarcity of trained human resources for its implementation.

A black-box decomposition approach for coupling heterogeneous components in hemodynamics simulations.

This work presents a generic and efficient black-box approach for the strong iterative coupling of dimensionally heterogeneous flow models in computational hemodynamics. A heterogeneous model of the cardiovascular system is formed by several vascular black-box components, which are connected through coupling equations. The associated system of equations is solved using the Broyden algorithm. In addition, a multiple time-stepping strategy is introduced to meet different component requirements. The proposed algorithm is employed to split a 3D-1D-0D closed-loop model of the cardiovascular system into corresponding black-box components standing for the 3D (specific vessels), 1D (systemic arteries/peripheral vessels), and 0D (venous/cardiac/pulmonary circulation) components. Examples of application are presented showing the robustness and suitability of this novel approach.

[Chronology of tropical dry forest regeneration in Santa Rosa, Guanacaste, Costa Rica. I. Edaphic characteristics]. / Cronología de la regeneración del bosque tropical seco en Santa Rosa, Guanacaste, Costa Rica. I. Características edáficas.

We characterized soil chemical and physical properties in eight tropical dry forest (TDF) successional sites along a time sequence (10, 15, 20, 40, 60 and >100 years) in Santa Rosa, Costa Rica. Seventeen soils were identified, described, and classified in six orders. Most soils were classified as Entisols and Vertisols, but Mollisols, Alfisols, Inceptisols and Ultisols were also present. All soils showed good fertility that did not constrain species richness. High edaphic variation seemed the result of complex interactions among the pyroclastic origin of Santa Rosa ignimbritic plateau (SRIP), the lithological composition and acidity of ignimbritic rocks, the strong seasonality in rainfall, intense hydric and aeolic erosion, topographic variations within the SRIP, and past human intervention. Correlations performed on soils classified as Entisols (<60 cm deep) showed a depletion of soil cations (Ca, Mg, K, Na and CEC) during the first 20 years of forest regeneration, that later recovered in mature TDF sites. Organic matter content did not change significantly along the TDF chrono-sequence. Substantial increments in macro-pores and soil hydraulic conductivity were observed, probably resulting from higher root biomass and turnover in older successional sites. Soil available water and meso-pore abundance were negatively correlated with TDF successional age. Our results indicate that edaphic changes observed along TDF regeneration might have been due to annual fires in pastures and young TDF sites, addition of decaying litter and fine roots as regeneration progressed, milder microclimate conditions during late regeneration in mature TDF sites, increased nutrient cycling, and the predominance of sandy loam textures among the soils examined. These changes in the soil environment with succession may have physiological and phenological consequences on the species appearing at different stages of TDF regeneration.

[Chronology of tropical dry forest regeneration in Santa Rosa, Guanacaste, Costa Rica. II. Vegetation in relation to the soil]. / Cronología de la regeneración del bosque tropical seco en Santa Rosa, Guanacaste, Costa Rica. II. La vegetación en relación con el suelo.

Tropical dry forest (TDF) succession was monitored in Santa Rosa, Costa Rica. We analyzed the effect of soil type on forest structure and diversity. Eight seasonally-dry TDF sites located along a successional chrono-sequence (10, 15, 20, 40, 60 and >100 years) were examined in relation to 17 soil pedons and six soil orders. Soils had moderate to high fertility and were classified as Entisols and Vertisols, although Mollisols, Alfisols, Inceptisols and Ultisols were also present. One-hundred and thirty 500 m2 plots were established, 20 plots in secondary and 10 plots in mature TDF sites. Diameter at breast height (dbh) and total tree height were measured for saplings (dbh > or = 1 and <5 cm), shrubs and trees (dbh > or = 5 cm). With the exception of two sites (40 and 60 years), soil type did not have significant effects on forest structure. However, tree diversity measured with Shannon-Wiener's H' and Fisher's alpha rarefaction curves, showed substantial differences among soil types, which became accentuated in mature forests. This pattern might be explained by non-random distributions of TDF trees, the scale of the study, the plot shape, and the use of systematic sampling designs. Low-fertility sites in general had higher species richness, consistent with idea that more restrictive soils reduce competition among trees and allow co-existence of species with contrasting growth rates. Changes in soil properties along a chrono-sequence of Entisols indicated that trees may experience more severe water stress as succession progresses, which may require adjustments in biomass allocation and phenological behavior of the dominant species. Our results suggest that edaphic specialization is more pronounced in mature TDF forests, and that most TDF trees are generalists in relation to soil type, highly tolerant to site heterogeneity, and show little physiological specializations in response to edaphic heterogeneity.

Cronología de la regeneración del bosque tropical seco en Santa Rosa, Guanacaste, Costa Rica: I. Características edáficas

Chronology of tropical dry forest regeneration in Santa Rosa, Guanacaste, Costa Rica. I. Edaphic characteristics. We characterized soil chemical and physical properties in eight tropical dry forest (TDF) successional sites along a time sequence (10, 15, 20, 40, 60 and >100 years) in Santa Rosa, Costa Rica. Seventeen soils were identified, described, and classified in six orders. Most soils were classified as Entisols and Vertisols, but Mollisols, Alfisols, Inceptisols and Ultisols were also present. All soils showed good fertility that did not constrain species richness. High edaphic variation seemed the result of complex interactions among the pyroclastic origin of Santa Rosa ignimbritic plateau (SRIP), the lithological composition and acidity of ignimbritic rocks, the strong seasonality in rainfall, intense hydric and aeolic erosion, topographic variations within the SRIP, and past human intervention. Correlations performed on soils classified as Entisols (<60 cm deep) showed a depletion of soil cations (Ca, Mg, K, Na and CEC) during the first 20 years of forest regeneration, that later recovered in mature TDF sites. Organic matter content did not change significantly along the TDF chrono-sequence. Substantial increments in macro-pores and soil hydraulic conductivity were observed, probably resulting from higher root biomass and turnover in older successional sites. Soil available water and meso-pore abundance were negatively correlated with TDF successional age. Our results indicate that edaphic chan ges observed along TDF regeneration might have been due to annual fires in pastures and young TDF sites, addition of decaying litter and fine roots as regeneration progressed, milder microclimate conditions during late regeneration in mature TDF sites, increased nutrient cycling, and the predominance of sandy loam textures among the soils examined. These changes in the soil environment with succession may have physiological and phenological consequences on the species appearing at different stages of TDF regeneration. Rev. Biol. Trop. 57 (3): 801-815. Epub 2009 September, 30.

Se caracterizaron las propiedades químicas y físicas de los suelos a lo largo de una cronosecuencia de ocho fragmentos de bosque tropical estacionalmente seco (BTS) en Santa Rosa, Costa Rica, y se relacionaron con el estado sucesional de los sitios (10, 15, 20, 40, 60 y >100 años de regeneración). Se encontró una alta diversidad edáfica a escalas pequeñas (0.5-1 ha) y se describieron 17 clases dominantes de suelos, clasificados en seis órdenes. La mayoría de los suelos fueron clasificados como Entisoles y Vertisoles, pero los Mollisoles, Alfisoles, Inceptisoles y Ultisoles estuvieron representados también. Todos los suelos presentaron buenos índices de fertilidad que no restringieron la riqueza de las especies. La alta heterogeneidad edáfica pareció ser el resultado de la interacción entre el origen piroclástico de la meseta ignimbrítica de Santa Rosa, la composición litológica y la acidez de las rocas del material parental, la marcada estacionalidad de la lluvia, intensos procesos de erosión hídrica y eólica, variaciones topográficas locales, y la historia de intervención humana. Correlaciones efectuadas en los Entisoles (<60 cm profundidad) revelaron un agotamiento de los cationes (Ca, Mg, K, Na y CIC) durante los primeros veinte años de regeneración, que más tarde se recuperaron en los bosque maduros. El contenido de materia orgánica no varió significativamente con la regeneración. Se observaron incrementos sustanciales en los macroporos y en la conductividad hidráulica, probablemente resultado de mayor biomasa y actividad radical en sitios sucesionales más viejos. La abundancia de mesoporos y el agua disponible para las plantas disminuyeron con la regeneración del bosque. Los resultados indican que los cambios observados en el suelo son resultado de la presencia anual de fuego, la adición de materia orgánica y minerales al suelo conforme la regeneración progresó, las condiciones microclimáticas más benignas conforme el bosque se desarrolló, el creciente ciclaje de nutrimentos, y la predominancia de texturas franco-arenosas en los suelos examinados. Estos cambios en las propiedades del suelo con la sucesión pueden tener importantes consecuencias sobre la fisiología y la fenología de las diversas formas de vida vegetal observadas durante la regeneración de los bosques tropicales estacionalmente secos.

Cronología de la regeneración del bosque tropical seco en Santa Rosa, Guanacaste, Costa Rica: II. La vegetación en relación con el suelo

Chronology of tropical dry forest regeneration in Santa Rosa, Guanacaste, Costa Rica. II. Vegetation in relation to the soil. Tropical dry forest (TDF) succession was monitored in Santa Rosa, Costa Rica. We analyzed the effect of soil type on forest structure and diversity. Eight seasonally-dry TDF sites located along a successional chrono-sequence (10, 15, 20, 40, 60 and >100 years) were examined in relation to 17 soil pedons and six soil orders. Soils had moderate to high fertility and were classified as Entisols and Vertisols, although Mollisols, Alfisols, Inceptisols and Ultisols were also present. One-hundred and thirty 500 m2 plots were established, 20 plots in secondary and 10 plots in mature TDFsites. Diameter at breast height (dbh) and total tree height were measured for saplings (dbh ≥1 and <5 cm), shrubs and trees (dbh ≥5 cm). With the exception of two sites (40 and 60 years), soil type did not have significant effects on forest structure. However, tree diversity measured with Shannon-Wiener’s H’ and Fisher’s α rarefaction curves, showed substantial differences among soil types, which became accentuated in mature forests. This pattern might be explained by non-random distributions of TDF trees, the scale of the study, the plot shape, and the use of systematic sampling designs. Low-fertility sites in general had higher species richness, consistent with idea that more restrictive soils reduce competition among trees and allow co-existence of species with contrasting growth rates. Changes in soil properties along a chrono-sequence of Entisols indicated that trees may experience more severe water stress as succession progresses, which may require adjustments in biomass allocation and phenological behavior of the dominant species. Our results suggest that edaphic specialization is more pronounced in mature TDF forests, and that most TDF trees are generalists in relation to soil type, highly tolerant to site heterogeneity, and show little physiological specializations in response to edaphic heterogeneity. Rev. Biol. Trop. 57 (3): 817-836. Epub 2009 September 30.

Se estudió la sucesión del bosque tropical seco (BTS) de Santa Rosa, Guanacaste, Costa Rica, en cinco sitios boscosos secundarios y tres bosques maduros. Se analizó el efecto de la clase de suelo sobre la estructura del bosque y la diversidad de especies arbóreas. Los ocho sitios sucesionales estaban localizados a lo largo de una cronosecuencia de regeneración (10, 15, 20, 40, 60 and >100 años) en la que se identificaron 17 pedones y seis órdenes de suelos con moderada a alta fertilidad, clasificados como Entisoles y Vertisoles, aunque los Mollisoles, Alfisoles, Inceptisoles y Ultisoles estuvieron presentes también. Se establecieron 130 parcelas de 10 por 50 m (0.05 ha), 20 en cada bosque secundario y 10 en cada bosque antiguo (6.5 ha en total), de acuerdo con la topografía. Se midió el diámetro a la altura de pecho (dap) de todos los individuos presentes en cada parcela, la altura dominante y el área basal (m2ha-1), usando dos poblaciones: latizales (dap ≥ 1 y < 5 cm) y árboles (dap ≥ 5 cm). Cada bosque presentó al menos dos pedones de suelo bien diferenciados. La alta variación edáfica encontrada se debió posiblemente al origen piroclástico de la meseta ignimbrítica de Santa Rosa, las variaciones en los tiempos de deposición del material parental, y los patrones de erosión. A excepción de dos sitios, no se presentaron diferencias importantes en la estructura del bosque entre las clases de suelos examinadas, según la densidad de individuos, el área basal y la altura dominante. La diversidad de especies arbóreas medida según el índice Shannon-Wiener y las curvas de rarefacción construidas con el índice α de Fisher, presentaron diferencias considerables entre las clases de suelos. Esta tendencia se explicó por la influencia de las características edáficas sobre las distribuciones no aleatorias de las especies arbóreas, la escala de medición del estudio, la forma de la parcela, y el muestreo sistemático utilizado. En general, los suelos de menor fertilidad presentaron mayor riqueza de especies, indicando que los sitios más restrictivos redujeron la competencia y permitieron la coexistencia de individuos con tasas de crecimiento disímiles. Los cambios en las propiedades físicas encontrados a lo largo de una cronosecuencia de Entisoles indicaron que los árboles podrían experimentar estrés hídrico más severo conforme la sucesión avanza, lo que podría requerir ajustes en el comportamiento fenológico y en las propiedades ecofisiológicas de las especies dominantes. En general, nuestros resultados sugieren que la especialización edáfica es más pronunciada en BTS maduros, y que la mayoría de las especies del BTS son generalistas en relación con la clase de suelo, altamente tolerantes a la heterogeneidad de los sitios, y muestran poca especialización fisiológica para responder a la variabilidad edáfica en distancias cortas.

Use and overuse of proton pump inhibitors in cirrhotic patients.

BACKGROUND: There are several indications for the use of proton pump inhibitors (PPIs) but little evidence to support their use in patients with chronic liver disease. Moreover, the pattern of clinical use is unknown. The aim of the present study was to analyze the use of PPIs in patients with chronic liver disease in an ambulatory setting. MATERIAL/METHODS: This was a retrospective study in a clinical setting. Clinical variables, severity indexes, and endoscopic findings were assessed. Management of PPIs was classified according to proven indication as: G1, proven indication and a prescription; G2, no proven indication and prescription; G3, proven indication and no prescription; and G4, no proven indication and no prescription. G1+G4 were considered proper use of PPIs. The classification was used to identify variables associated with proper use. RESULTS: The study included 243 patients (mean age: 55.82+/-12.9 years). The most common etiologies of chronic liver disease were hepatitis C virus infection and chronic alcoholic liver disease. PPIs were indicated in 46.1% patients. Multivariate analysis showed that a MELD score < or =8 points (OR: 2.6, 95% CI: 1.3-5.3), esophageal varices (OR: 0.38, 95% CI: 0.16-0.90), and previous in-hospital use of PPIs (OR: 0.78, 95% CI: 0.6-0.9) were associated with G1+G4. CONCLUSIONS: Clinical use of PPIs in chronic liver disease was inappropriate in nearly one half of all patients. A less severe disease was associated with proper use and previous in-hospital use was associated with inappropriate use. Future research into the clinical use of PPIs in cirrhotic patients is mandatory.

Pathophysiology of ascites and dilutional hyponatremia: contemporary use of aquaretic agents.

Ascites, the most common complication of cirrhosis, is associated with a poor quality of life, an increased risk of infection, and renal failure. Twenty percent of cirrhotic patients have ascites at the time of diagnosis, while 30% and 50% will develop ascites by 5 and 10 years, respectively. There are several factors that contribute to ascites formation in cirrhotic patients, these include splanchnic vasodilatation, arterial hypotension, high cardiac output, and decreased vascular resistance. These factors lead to ineffective intravascular volume (hyperdynamic state), impairment of renal function, and subsequent water and sodium retention, all of which lead to dilutional hyponatremia (serum sodium <130 mEq/L), one of the most important prognostic factors in these patients. In conclusion, the therapeutic objective is to improve sodium balance and circulatory function through non-pharmacological measures, such as dietary sodium and water restriction as well as bed rest. Spironolactone (100-400 mg/day) is the initial drug of choice, while loop diuretics (like furosemide, 40-60 mg/day) are frequently used as adjuvants. Recently, agent that interfere with the renal effects of vasopressin by inhibiting water reabsorption in collecting ducts and producing free water diuresis have been used. These agents are called aquaretics and can be useful in the treatment o ascites unresponsive to conventional therapy.

Microscopic colitides: a single center experience in Mexico.

BACKGROUND/AIM: Microscopic colitis is characterized by chronic diarrhea and specific microscopic changes in a macroscopically normal colonic mucosa. In this paper, we report the clinical and histological features of a group of Mexican patients with microscopic colitis. MATERIALS AND METHODS: Patients were identified from 10 years of data in the pathology database of our institution. A pathologist reassessed all biopsy material. We included only patients who met strict histopathological criteria. Clinical data were obtained from medical records. RESULTS: Microscopic colitis was diagnosed in 26 cases. The female/male ratio was 1.8:1. The median age at diagnosis was 56.5 +/- 15.7 (range, 26-85) years. The most frequent symptoms were diarrhea in all, weight loss in 22 (84%), and abdominal pain in 18 (69%) patients. Sixteen (61%) patients reported associated diseases; autoimmune thyroid disorders were the most common. Drug-induced microscopic colitis was suspected in 12 (46%) patients. More than 80% of the treated patients improved or had clinical remission. CONCLUSION: Microscopic colitis is an uncommon colonic disease at our institution, representing less than 1% of the final diagnoses in mucosal colonic biopsies. It is the largest case series of microscopic colitis in the Mexican population.