The effect of heat treatment on hydrogen diffusion and trapping on the API 5CT P110 steel was investigated trough electrochemical permeation tests and microstructural analysis techniques. Samples of as-received steel were tempered at different temperatures to obtain hydrogen permeation and trapping parameters and to characterize microstructural modifications that may alter these parameters. After permeation tests on each heat-treatment condition were verified changes on hydrogen kinetic parameters. Microstructural analysis revelated changes in dislocations density and volumetric fraction of titanium carbides, responsible to alterations in diffusivity, solubility and in hydrogen trapping characteristics. As these carbides are considered irreversible hydrogen traps, are beneficial because they become the steels less susceptible to hydrogen embrittlement. Therefore, the results suggest that there is an optimal tempering temperature which can make the API 5CT P110 steel more resistant against hydrogen embrittlement, since promote the formation of a higher number of irreversible hydrogen traps. CT P P11 techniques asreceived as received heattreatment diffusivity characteristics traps embrittlement Therefore P1

BACKGROUND: Sarcoidosis is a multisystem granulomatous disorder. Its exact cause is unknown, but it is believed that an external agent may cause the characteristic immune reaction in genetically susceptible individuals. There is therefore general recognition that genetic vulnerability to sarcoidosis is one of the potential risk factors. HLA is encoded by genes in the major histocompatibility complex on chromosome 6. These surface cells are important in presentation of antigen and play a key part in the body's immune response to external antigens. Various HLA subtypes are more common in people with sarcoidosis than in those without. Variances in vulnerability, presentation, progression and prognosis have been related to different HLA phenotypes. HLA genes offer information into the factors driving sarcoidosis and prognosticating tools. However, in Africa, including South Africa (SA), there are no data on HLA types in relation to sarcoidosis OBJECTIVES: To determine HLA class I and II associations in SA sarcoidosis patients METHODS: Phenotype frequencies of HLA-A, B and C and DQB1 and DRB1 were calculated for 51 consecutive patients with biopsy-proven sarcoidosis attending the respiratory clinic at Charlotte Maxeke Johannesburg Academic Hospital and 63 controls, who were potential organ donors. The frequencies of the tested HLA loci were determined by direct counting. The significance of the associations between the various loci tested for and the presence or absence of sarcoidosis was estimated from 2 x 2 tables using the x² test RESULTS: Of the 51 patients, 70.6% were female. The mean age was 44.6 years. Analysis of HLA class I and class II phenotypes in sarcoidosis patients revealed a significant association with HLA-B15, C4, C7, C12, C15, C16, C17, DQ3, DR8 and DR11. In addition, a significant negative (protective) association with HLA A9, A28, B12, B17 and DR2 was observed CONCLUSION: This HLA study in SA patients suggests that genetic factors play a role in the causation of sarcoidosis. Some HLA subtypes have a significant association with sarcoidosis in SA patients, while other subtypes may be protective. The study supported the association of HLA antigens with sarcoidosis and implies that there is a genetic predisposition to sarcoidosis in the SA population

BACKGROUND. Both fibroblast growth factor-23 (FGF-23) and fetuin-A levels have been implicated in mineral and bone disorders associated with chronic kidney disease (CKD), and several single nucleotide polymorphisms (SNPs) of the fetuin-A gene have also been associated with fetuin-A levels.OBJECTIVES. This study aimed to determine the relationship between FGF-23 and fetuin-A and to determine the role of fetuin-A SNPs with respect to fetuin-A levels and markers of bone mineralisation in black South African children.METHODS. Blood samples from 93 children (5 - 18 years) with various stages of CKD were assessed for C-reactive protein (CRP), calcium, phosphate, parathyroid hormone, 25-hydroxyvitamin D, FGF-23 and fetuin-A levels. Genomic DNA was extracted from whole blood and regions of the fetuin-A gene amplified by polymerase chain reaction. SNPs were genotyped by restriction fragment length polymorphism analysis or by direct sequencing.RESULTS. The median FGF-23 and fetuin-A levels were 28.9 (11.7 - 147.1) pg/mL and 57.7 (37.7 - 71.8) mg/dL, respectively. A significant negative relationship between fetuin-A and FGF-23 was only observed in the CKD V group (p=-0.60, p<0.001). Plasma FGF-23 levels correlated better with markers of bone mineralisation than fetuin-A. We found significant association of the fetuin-A SNPs rs4918-G and rs2070633-T alleles with log-transformed fetuin-A levels. Serum phosphate and parathyroid hormone levels were also associated with fetuin-A SNPs.CONCLUSION. Plasma FGF-23 levels increase with CKD progression while changes in fetuin-A levels are more likely to be observed in children with advanced CKD; and FGF-23 correlated better with markers of bone mineralisation than fetuin-A.

Resumo O objetivo desse estudo in vitro foi avaliar a influência de agentes clareadores na rugosidade superficial e na microdureza de uma cerâmica odontológica (porcelana). Foram confeccionadas 30 amostras de cerâmica odontológica de 2 mm de espessura e 6 mm de diâmetro de acordo com as instruções do fabricante. Posteriormente, as amostras foram aleatoriamente divididas em 3 grupos (n=10) e avaliadas quanto à rugosidade e à microdureza para obtenção dos valores iniciais. Dois grupos foram submetidos ao tratamento superficial com agentes clareadores (GII: peróxido de hidrogênio a 9,5% e GIII: peróxido de hidrogênio a 37,5%). O GI, que constituiu o grupo controle, ficou imerso em água destilada. O peróxido de hidrogênio a 9,5% foi aplicado 3 h/dia por 3 semanas. O agente mais concentrado foi utilizado 3 vezes ao dia, por 8 min durante 3 semanas (uma vez por semana). Ao fim de cada exposição ao agente clareador, os espécimes foram lavados e armazenados em água destilada. Os dados obtidos relativos à rugosidade e à microdureza dos espécimes cerâmicos foram registrados nos intervalos de tempo: inicial (baseline) e 3 semanas após a aplicação dos agentes clareadores. A rugosidade e a microdureza de superfície não foram alteradas de maneira estatisticamente significativa, considerando o tempo de clareamento, independente do grupo analisado (p> 0,05). Os valores médios da rugosidade (Ra em μm) foram: GI (0,084, 0,086, 0,078, 0,083), GII (0,085, 0,085, 0,086, 0,080) e GIII (0,079, 0,088, 0,083, 0,086). Os valores médios de microdureza (VHN em kgf/mm2) foram: GI (618, 589), GII (573, 578) e GIII (584, 600). Concluiu-se que as propriedades superficiais (rugosidade e microdureza) da cerâmica odontológica não foram alteradas pelo tratamento clareador. Novas pesquisas são necessárias para explicar o efeito do clareamento em cerâmicas odontológicas.

Abstract The objective of this in vitro study was to evaluate the effect of bleaching agents on the surface roughness and microhardness of a dental ceramic (porcelain). Thirty samples of dental ceramic, 2 mm thick and 6 mm in diameter, were prepared according to manufacturer's instructions, randomly divided into three groups of 10, and their initial baseline roughness and microhardness values recorded. Two groups were submitted to surface treatment with bleaching agents (GII, hydrogen peroxide 9.5%; and GIII, hydrogen peroxide 37.5%). The third group, GI, remained immersed in distilled water constituting the control group. GII group was exposed to the bleaching agent three hours a day for three weeks. As for the GIII group, the bleaching agent was applied three times a day, for eight minutes, during three weeks (once a week). After each exposure to the bleaching agent, the samples were washed and stored in distilled water. The roughness and microhardness data for the different ceramic specimens were collected at time intervals: initial (baseline) and every 3 weeks after bleaching agent applications. None of the bleaching treatments applied altered the roughness or the micro-hardness of the ceramic surfaces in any statistically significant way (p>0.05). Average roughness (Ra in μm) values registered were: for GI (0.084, 0.086, 0.078, 0,083); for GII (0.085, 0.085, 0.086, 0.080); and for GIII (0.079, 0.088, 0.083, 0.086). Average microhardness (VHN in kgf/mm2) values registered were: for GI (618, 589); for GII (573, 578); and for GIII (584, 600). It is concluded that the dental ceramic' surface properties (roughness and microhardness) were not altered by the bleaching treatments applied. Additional studies are necessary to understand and explain the effect of bleaching on dental ceramics.

BACKGROUND: Despite ranking third as a cause of hospital-acquired acute kidney injury (AKI), iatrogenic contrast-induced nephropathy (CIN) impacts significantly on morbidity and mortality and is associated with high hospital costs. In sub-Saharan Africa, the rates and risk factors for CIN and patient outcomes remain unexplored. METHODS: We conducted a prospective observational study at the Charlotte Maxeke Johannesburg Academic Hospital, South Africa, from 1 July 2014 to 30 July 2015. Hospitalised patients undergoing computed tomography scan contrast media administration and angiography were consecutively recruited to the study and followed up for development of AKI. CIN was defined as an increase in serum creatinine >25% or an absolute increase of >44 μmol/L from baseline at 48 - 72 hours post exposure to contrast media. Outcome variables were the occurrence of CIN, length of hospitalisation and in-hospital mortality. RESULTS: We recruited 371 hospitalised patients with a mean (standard deviation) age of 49.3 (15.9). The rates of CIN, assessed using an absolute or relative increase in serum creatinine from baseline, were 4.6% and 16.4%, respectively. Anaemia was an independent predictor for the development of CIN (risk ratio (RR) 1.71, 95% confidence interval (CI) 1.01 - 2.87; p=0.04). The median serum albumin was 34 g/L (interquartile range (IQR) 29 - 39.5) and 38 g/L (IQR 31 - 42) in the CIN and control groups, respectively (p=0.01), and showed a significant trend for CIN development (RR 1.68, 95% CI 0.96 - 2.92; p=0.06). Mortality was significantly increased in the CIN group (22.4% v. 6.8%; p<0.001), and CIN together with anaemia increased mortality twofold (RR 2.39, 95% CI 1.20 - 4.75; p=0.01) and threefold (RR 3.32, 95% CI 1.48 - 7.43; p=0.003), respectively. CONCLUSIONS: CIN has a relatively high incidence in sub-Saharan Africa and predicts poorer clinical outcomes. The presence of CIN and anaemia positively predicted mortality. Caution should be exercised in patients with hypoalbuminaemia and anaemia undergoing contrast media administration.

Introduction: Ocimum micranthum Willd is a herbaceous plant of the family Lamiaceae native to tropical and subtropical regions of America and grown for medicinal and/or ornamental purposes. Infusion of this plant is used for gastrointestinal conditions such as ulcers, gastritis, intestinal fever, inflammation, dysentery, vomiting, stomach pain and as vermifuge. Objectives: determine the volatile chemical composition of essential oil from Ocimum micranthum Willd and evaluate its in vitro antifungal, repellent, insecticidal and antioxidant activities. Methods: essential oil (EO) from O. micranthum fresh leaves was obtained by hydrodistillation. Volatile chemical composition was determined by gas chromatography coupled to a mass spectrometric detector (GC-MS). The fumigant activity assay (insecticidal) was performed against Sitophilus zeamais . Antifungal activity was determined against pathogenic fungus Fusarium oxysporum f. sp. Dianthi, and repellent activity against Tribolium castaneum Herbst. Antioxidant capacity was analyzed with the DPPH radical decolorization assay. Results: the most abundant compound found in O. micranthum EO was eugenol (60.37 %), followed by eucalyptol (12.09 %), cis-terpineol (4.25 %), a-terpineol (4.43 %), and δ-cadinene (1.27 %). O. micranthum EO was active against F. oxysporum, with a mycelial inhibition of 98.8 % at 176.5 uL EO / L air, read at 72 hours, and a mortality rate of 66.7 % against S. zeamais at 500 uL EO / L air, after 24 hours of exposure. Repellent activity was 92.5 % and 93.3 % at 2 and 4 hours of exposure, respectively. DPPH radical inhibition was 93.92 %. Conclusions: Essential oil from O. micranthum showed significant antifungal, repellent and fumigant activities. Thus it could become an alternative to replace synthetic fungicides and insecticides.

Introducción: Ocimum micranthum Willd, es una planta herbácea, perteneciente a la familia de las Lamiáceas, originaria de las regiones tropicales y subtropicales de América, cultivada con fines medicinales y/o ornamentales. La infusión de esta planta es usada para enfermedades de tipo gastrointestinal como úlceras, gastritis, fiebre intestinal, inflamación; disentería, vómito, dolor de estómago y vermífugo. Objetivos: determinar la composición química volátil del aceite esencial de Ocimum micranthum Willd y evaluar in vitro las actividades antifúngica, repelente, insecticida y antioxidante. Métodos : el aceite esencial (AE) fue obtenido de hojas frescas de O. micranthum por hidrodestilación, la composición química volátil fue determinada mediante cromatografía de gases acoplada a detector de espectrometría de masas (GC-MS). El ensayo de actividad fumigante (insecticida) del AE se realizó sobre Sitophilus zeamais. La actividad antifúngica sobre el hongo fitopatógeno ( Fusarium oxysporumf. sp. Dianthi), la actividad repelente contra el Tribolium castaneum Herbst y la capacidad antioxidante se efectuóa través del ensayo de decoloración del radical DPPH. Resultados: el compuesto mayoritario encontrado en el AE de O. micranthum fue el eugenol (60,37 %), seguido de eucaliptol (12,09 %), cis b-terpineol (4,25 %) y a-terpineol (4,43 %), a-cadineno (1,27 %). El AE de O. micranthum fue activo contra F. oxysporum con un porcentaje de inhibición micelar de 98,8 % a 176,5 µL de AE/L aire, leído a las 72 horas; y un porcentaje de mortalidad contra S. zeamais de 66,7 % a 500 µL de AE/L de aire, después de 24 horas de exposición. La actividad repelente fue de 92,5 % y 93,3 % a las 2 y 4 horas de exposición, respectivamente. El porcentaje de inhibición del radical DPPH• fue de 93,92 %. Conclusiones: El aceite esencial de O. micranthum mostró una significativa actividad fungicida, repelente y fumigante, por lo cual puede llegar a ser una alternativa en reemplazo de fungicidas e insecticidas sintéticos.

El control del Aedes aegypti (vector principal del Dengue), se dificulta por la extensión y heterogeneidad de los barrios donde se encuentran los criaderos, la carencia de acceso permanente a servicios públicos y por la ausencia de vigilancia epidemiológica estricta y constante. Se registraron 2.603 casos de dengue confirmados por IgM-dengue, durante el período 1995-2010. El estudio se realizó en Puerto Ayacucho, capital del estado Amazonas con 98.824 habitantes. Los casos confirmados se agruparon de acuerdo con la localización de su residencia. La información se representó espacialmente para analizar los patrones espacio-temporales del dengue, estableciéndose una estratificación de la ciudad. La prevalencia de dengue mostró una correlación positiva con la persistencia por barrio, lo que permitió agruparlos en dos clases: (1) alta prevalencia y persistencia, con 66% de los casos confirmados, y (2) baja prevalencia y persistencia, con 34% de los casos. Se demuestra que en Puerto Ayacucho existen “focos calientes” o de mayor transmisión y “focos fríos” o de transmisión transitoria. En conjunto, los barrios incluidos en la categoría de alta prevalencia y persistencia representan 65,1% del área urbana. Este es el espacio geográfico en el cual recomendamos concentrar los esfuerzos de control. La estratificación de la ciudad e identificación de los barrios productores de casos, mostrando las áreas donde es más probable la transmisión del virus, permitirá concentrar los esfuerzos para mitigarla. El enfoque de las actividades de control basado en una estratificación, permite dirigir los programas hacia áreas más problemáticas.

Control of Aedes aegypti is difficult to perform due to the extent and variety of neighborhoods where the breeding grounds are found, the lack of permanent access to public services, and to the absence of a strict and constant epidemiological surveillance. 2,603 confirmed dengue cases (IgM-dengue) were recorded during the 1995-2010 period. This study was carried out in Puerto Ayacucho, main city of Amazonas State, Venezuela, with 98,824 inhabitants. Confirmed cases of individuals affected were grouped according to the location of their residence. Information is spatially represented to analyze space-time patterns of dengue, establishing a stratification of the city. The prevalence of dengue showed a positive correlation with the persistence per neighborhood, allowing to group the neighborhoods into two classes: (1) High prevalence and persistence, with 66% of the confirmed cases, and (2) low prevalence and persistence, with 34% cases. The study shows there are "hot spots" or higher transmission areas, and "cold spots" or transient transmission areas in Puerto Ayacucho. All the neighborhoods included in the category of high prevalence and persistence represent 65.1% of the urban area. This is the geographical area in which we recommend to concentrate control efforts. The stratification of the city and the identification of case-producing neighborhoods, showing the areas where virus transmission is most likely, will permit concentrating efforts to mitigate it. Focus of control activities based on a stratification study allows directing programs to most problematic areas.

Los pesticidas organofosforados son esteres del ácido fosfórico (OPs), frecuentemente utilizados como insecticidas y acaricidas. Son un grupo muy importante de contaminantes ambientales empleados en la agricultura intensiva para la protección contra las plagas, producen disturbios en las reacciones bioquímicas normales necesarias para el metabolismo, exhiben un amplio rango de toxicidad para los mamíferos y actúan sobre el sistema nervioso central como inhibidores de la acetilcolinesterasa. En este estudio se evaluó la concentración letal media (CL50) de diecisiete compuestos organofosforados usando Artemia franciscana. El compuesto que presentó mayor toxicidad fue el fentión con CL50 de 6,26 µg/mL a las 24h de exposición y de 0,11 µg/mL a las 48h y aquellos con menor toxicidad fueron: clorpirifos y malatión con valores de CL50 mayores de 100 µg/mL.Modelos QSAR (relación cuantitativa existente entre la estructura y la actividad) fueron desarrollados para predecir la toxicidad de los OPs correlacionando sus valores LC50 con descriptores moleculares,usando métodos computacionales y herramientas estadísticas. El momento dipolar (µ) y el coeficiente de partición octanol/agua (LogP) fueron los descriptores moleculares que presentaron la mejor correlación lineal con R2 de 0,8107 y 0,8546 para 24 y 48 h de exposición,respectivamente, de OPsfrente A. franciscana.

Organophosphate pesticides are phosphoric acid esters (OPs) often used as insecticides and acaricides. They are a very important group of environmental pollutants used in intensive agriculture for protection against pests, produce disturbances in biochemical reactions necessary for normal metabolism, exhibit a wide range of mammalian toxicity and act on the central nervous system as inhibitors of acetylcholinesterase. In this study, the median lethal concentration (LC50) of seventeen organophosphorus compounds against Artemiafranciscana was evaluated. The most toxic compound was Fenthion with LC50 of 6,26 µg/mL at 24 h of exposure and 0,11 µg/mL at 48 h; and those with less toxicity were Chlorpyrifos and Malathion with LC50 values greater than 100 µg/mL. Quantitative structure activity relationships (QSAR) models were developed to predict toxicity of OPs by correlating LC50 values with molecular descriptors by using computational methods and statistical tools. The molecular descriptors, which showed the best relationship, were Dipole moment (µ) and the partition coefficient octanol/water (LogP). They showed a significant linear correlation with R2 of 0,8107 and 0,8546 for 24 h and 48 h of exposure against A. franciscana respectively.

Pesticidas organofosforados são ésteres de ácido fosfórico (PO), são muitas vezes utilizados como inseticidas e acaricidas. Eles são um grupo muito importante de poluentes ambientais utilizados na agricultura intensiva para a protecção contra as pragas, produzem perturbações em reacções bioquímicas necessárias para o metabolismo normal, exibem uma vasta gama de toxicidade para os mamíferos e actuam sobre os inibidores centrais do sistema nervoso da acetilcolinesterase. Neste estudo, foi avaliada a toxicidade de 17 compostos organofosforados usando A. franciscana. Ocomposto mostrou-secommaior toxicidadeLC50fentião6,26µg/mL após 24horas de exposiçãoe 0,11µg/mL às 48 heaqueles com menostoxicidade foramclorpirifos emalationcomvalores LC50superior a 100µg/mL. QSAR (relação quantitativa entre a estruturae atividade) foram desenvolvidos para prevera toxicidade dePOCL50correlacionandocom descritoresmoleculares,usando métodos computacionaise ferramentas estatísticas. Omomento de dipolo(μ) e do coeficiente de partição octanol/ água (LogP) descritores moleculares foio que apresentou melhorcorrelação linearcom R2 de0,8107e0,8546por 24 e 48h de exposiçãoa organofosforadoscontra A.franciscana,respectivamente.

Este trabalho teve como objetivo o estudo de armaduras de cilindros de betão armado confinados com duas camadas de polímeros reforçados com fibras de vidro (GFRP). Provetes cilíndricos de betão armado com e sem GFRP foram imersos em solução de cloreto de sódio. O estado das armaduras foi avaliado por medições de potencial de circuito aberto e por impedância eletroquímica com sistemas a dois e três eletrodos. Os resultados demostraram que o confinamento de duas camadas de GFRP apresenta baixa permeabilidade e atua como barreira física à penetração de solução. Verificou-se que imperfeições na fase de aplicação do GFRP e sua degradação são de grande importância na eficiência da prevenção de corrosão.

This work aims to study the steel reinforcement corrosion in reinforced concrete confined with two layers of glass fiber reinforced polymers (GFRP). Reinforced concrete cylinders with and without GFRP were immersed in a sodium chloride solution. T he corrosion process of the steel rebars was followed by open potential measurements and electrochemical impedance in two and three electrodes systems. Results have shown that two GFRP layers have low permeability and act as an efficient physical barrier. It has been found that imperfections during the GFRP application and its degradation are of great importance in the efficiency of corrosion prevention.

El dengue se ha ido incrementando significativamente en la región de las Américas e islas del Caribe en las últimas dos décadas. Venezuela ha presentado las mayores tasas de incidencia de DH y el mayor número de fallecidos. En el estado Amazonas se reportan los primeros casos de dengue en el año 1995, siendo el municipio Atures el más afectado. El presente trabajo describe el comportamiento del dengue en el estado Amazonas durante los años 1995 al 2008, mediante la revisión de los registros epidemiológicos y análisis de serotipos del virus DENV. Durante el período 1995-2008 se registró un total de 6209 casos de dengue y 27 con DH, con tres epidemias, quedando demostrada la circulación de los 4 serotipos. Durante las 3 epidemias se hospitalizaron 94 pacientes con Dengue y solo 12 con diagnóstico de DH de 33 con criterios para DH según OPS. En 1995 se registraron 546 casos de dengue, con un solo deceso reportado. La prevalencia anual del Dengue disminuyó en los años 1996-2000 de manera significativa con respecto al año de la epidemia para nuevamente ascender en el año 2001 a cifras de positividad superiores a las del año 1995. Desde el 2003 hasta la fecha el número de casos ha ido en ascenso con presencia significativa de casos de DH. Es necesario que a nivel de la Dirección Regional se estructure un Plan de Control a fin de mantener un Sistema activo de Vigilancia y se revisen periódicamente las pautas de criterios para definir DH.

Dengue fever (DF) has been significantly increasing in the Americas and the Caribbean islands over the past two decades. Venezuela has presented the highest incidence of dengue hemorrhagic fever (DHF) and the largest number of deaths. In Amazonas state the first cases of dengue were reported in 1995, being Atures the most affected municipality. This paper describes the behavior of dengue in the Ama zonas state in the years 1995 to 2008, by reviewing records and epidemiological analysis of DENV virus serotypes. In that period a total of 6209 dengue cases and 27 DHF cases was reported, with three epidemics, proving the movement of the 4 serotypes. During the epidemics 94 pa - tients with dengue were hospitalized, and only 12 were diag nosed with DHF of 33 with PAHO criteria. In 1995 there were 546 dengue cases with one death registered. The an - nual prevalence of dengue significantly declined in the years 1996-2000 compared to the year of the epidemic, but it rose again in 2001 to positive figures higher than 1995. From 2003 until today the number of cases has been increasing with a significant presence of DHF cases. Therefore, it is necessary that in the Regional Health Division a control plan be structured in order to maintain a Monitoring System and periodic reviews of guidelines defining criteria for DHF.

The transcondylar approach (TA) has been used in surgeries to access lesions in areas close to the foramen magnum (FM) and is performed directly through the occipital condyle (OC) or through the atlanto-occipital joint and adjacent portions of the same. The objective of this study is to examine anatomical variations related to the TA by morphometric parameters of the FM, OC and of the hypoglossal canal (HC) in dry skulls and in computed tomography (CT). In 111 skulls, characteristics of the HC, and measures related to the FM, the HC and to the OC were examined. In CT, the measurements obtained bilaterally in 10 patients who underwent examination of the skull base in 1 mm-thick axial helical cuts were the distances from the outer half of the clivus to the opening of the HC; from the lower portion of the OC to the middle of HC; from the inner half of the clivus to the intracranial opening of the HC and to the midpoint of the HC; from the HC extracranial opening to the lower portion of the OC and to the outer half of the clivus. The results of CT measurements are consistent to previous studies of morphometric variations related to the TA, with no significant difference between the measurements obtained in the right and in the left sides, or related to gender. The data obtained by three-dimensional CT images are important in assessing the morphometric variations of pre-surgical patientsof TA.

El acceso transcondilar (AT)ha sido utilizado comoun procedimiento quirúrgico para lesiones cercanas al foramen magnum(FM)y se realizadirectamente a través delcóndilooccipital (CO)o por medio delas porciones atlanto-occipitalconjuntay adyacentesde lamisma.El objetivo del presenteestudio fue examinarlas variaciones anatómicas relacionadas con el AT mediantelos parámetros morfométricos del FM, CO y el canal delhipogloso (CH) en cráneossecos y tomografía computadorizada (CT). En 111 cráneos fueron examinadas las característicasdel CH y tomadas medidas relacionadas con el FM, CO y CH. En la CT, las mediciones se obtuvieron de forma bilateral en10 pacientes que se sometieron a exámen de la base del cráneo en corte axial helicoidal de 1mm de espesor. Las medidas tomadas fueron las distancias: de la mitad exterior del clivus a la apertura del CH; de la parte inferior de las emisiones de CO a la mitad del CH; de la mitad interna del clivus a la apertura intracraneal del CH y hasta el punto medio del CH; de la apertura extracraneal del CH a la parte inferior de las emisiones de CO y hasta la mitad exterior del clivus. Los resultados de las mediciones de CT son consistentes con estudios prévios de los cambios morfométricos en relación con AT, sin diferencia significativa entre las mediciones obtenidas en el lado derecho e izquierdo y ni en relación con el sexo. Los datos obtenidos a través de imágenes en tres dimensiones de CT son importantes para evaluarlas variaciones morfométricas de pre-quirúrgicos en el AT.

The nutrient removal capacity of two species of mangrove (Rhizophora mangle and Laguncularia racemosa) was assessed in shrimp (Litopenaeus vannamei) culture ponds. One pond contained R. mangle seedlings and another L. racemosa seedlings, while a third (control pond) was left without seedlings. Treatment ponds contained 20 floating platforms with 720 mangrove seedlings. Water was pumped from the estuary into the ponds. Nutrient (NO3-, NO2-, NH4+, and PO4-3) concentrations from the pond effluents were analyzed during the water exchange every 10 days. The results showed that L. racemosa removed 83.4% of dissolved inorganic nitrogen (DIN) and 45% of PO4 and R. mangle removed 79% of DIN and 40% of PO4, while 30% of DIN and 23% of PO4 was removed in the control pond. The flux of nutrients from the influent water to the ponds was 7269 g of N and 3095 g of P. In the ponds with mangroves, the nutrients were reduced to 1018-1071 g of N and 609-724 g of P. In the control pond, the effluent water nutrient concentrations were 5564 g of N and 1583 g of P. The nutrients accumulated in the mangrove tissue were 18,014-16,711 g of N and 5976-5832 g of P. Volatilization of ammonium and adsorption of phosphorus by sediments were 17,298-18,570 g of N and 6249-6268 g of P, and in the control pond, 30,022 g of N and 10,922 g of P, respectively. The final length for L. racemosa was 48 cm and the root length was 54 cm. For R. mangle, the final length was 38 cm and the root length was 46 cm. Shrimp survival was 70%, with individuals reaching 10.4 g in weight and 12.2 cm in length. We concluded that the nutrient removal percentage in ponds with mangrove seedlings was higher than in the pond without seedlings, improving water quality and reducing nutrients in the effluent.

Se evaluó la capacidad de remoción de nutrientes de dos especies de mangle (Rhizophora mangle y Laguncularia racemosa) en estanques de cultivo con camarón (Litopenaeus vannamei). Los estanques se sembraron con R. mangle, con L. racemosa y sin plántulas (control). Cada estanque contenía 20 plataformas flotantes con 720 plántulas. El agua se bombeó del estuario hacia los estanques. Se analizó la cantidad de nutrientes (NO3-, NO2-, NH4+ y PO4-3) de los efluentes durante el recambio de agua, cada 10 días. Los resultados mostraron que L. racemosa removió 83.4% del nitrógeno inorgánico disuelto (NID) y 45% de PO4, y R. mangle removió 79% del NID y 40% de PO4. En el estanque control el NID fue 30% y el PO4 fue 23%. La concentración de nutrientes en el agua de entrada fue de 7269 g de N y 3095 g de P. En los estanques con mangle los nutrientes disminuyeron a 1018-1071 g de N y 609-724 g de P. En el estanque control la concentración de nutrientes en el agua de salida alcanzó hasta 5564 g de N y 1583 g de P. Los mangles acumularon nutrientes en sus tejidos, entre 18,014 y 16,711g de N y entre 5976 y 5832 g de P. La volatilización de amonio y la adsorción por los sedimentos de fósforo variaron de 17,298 a 18,570 g de N y de 6249 a 6268 g de P, respectivamente. En el estanque control éstas fueron 30,022 g de N y 10,922 g de P. La longitud final de L. racemosa fue de 48 cm y 54 cm de raíz y de R. mangle, 38 cm y 46 cm de raíz. La supervivencia del camarón fue de 70%, y los individuos alcanzaron un peso de 10.4 g y una longitud de 12.2 cm. Se concluye que el porcentaje de remoción fue mayor en los estanques con plántulas de mangle que sin plántulas, lo que mejoró la calidad del agua y redujo los nutrientes en el efluente.

Introduction: plants have developed self-protecting chemical mechanisms to avoid being attacked by insects, fungi, bacteria, and viruses. The diseases caused by these pests are controlled with pesticides of high toxicity, therefore, it is necessary to use alternative compounds like essential oils. Essential oils are potential botanical sources of compounds having the same function as the pesticides. However, they have some advantages over the latter such as low toxicity for mammal, high volatility and toxicity for pests and microorganisms which attack stored products. Its volatile insecticidal property made it to be known as fumigant. Chenopodium ambrosioides L. (Chenopodiaceae) has been reported for its potential antiparasitic properties, including antiprotozoal activity. Objective: this study determine the fumigant, antifungal, and antioxidant activities of essential oils isolated from Chenopodium ambrosioides L. and their volatile chemical composition. Methods: the essential oil (EO) was obtained from leaves of C. ambrosioides by hydrodistillation whereas the volatile chemical composition was determined by gas chromatography coupled with mass spectrometry detector (GC-MS). The fumigant activity assay of the essential oil was performed against Sitophilus zeamais. The antifungal activity on plant pathogenic fungus (Fusarium oxysporum f. sp. Dianthi) and the antioxidant potential were determined through the discoloration test of DPPH. radical. Results: the major component found in the essential oil from C. ambrosioides was a-terpinene (60.29 %), followed by p-cymene (20.49 %), 4-carene (7.96 %) and trans-ascaridol (1.91 %). C. ambrosioides was active against Fusarium oxysporum, with a mycelial inhibition of 97.3 % at 176.5 µL EO/L air after 72 h of exposure; and a mortality rate against Sitophilus zeamais of 100% at 500 µL of essential oil per air liter after 24 h of exposure. The inhibition percentage of DPPH• radical was 84.89 %. Conclusions: this study demonstrated that C. ambrosioides essential oil exhibits important fungicidal activity on F. oxysporum and fumigant on S. zeamais, which could become an alternative to synthetic fungicides and insecticides.

Introducción: las plantas tienen mecanismos químicos de autoprotección para evitar ser atacadas por insectos, hongos, bacterias y virus. Las enfermedades producidas por estas plagas son controladas con plaguicidas, que presentan alta toxicidad; por esto, es necesario usar compuestos alternativos como aceites esenciales. Estas sustancias son fuentes botánicas potenciales que cumplen la misma función de los plaguicidas, con la ventaja de que presentan baja toxicidad para los mamíferos, alta volatilidad y toxicidad para los insectos y microorganismos que atacan los productos de cosecha almacenados, por ser volátiles su propiedad insecticida se conoce como fumigante. Chenopodium ambrosioides L. (Chenopodiaceae) ha sido reportada por sus potentes propiedades antiparasitarias, incluida la actividad antiprotozoaria. Objetivo: determinar la actividad fumigante, antifúngica y antioxidante del aceite esencial de Chenopodium ambrosioides y su composición química volátil. Métodos: el aceite esencial fue obtenido de hojas de C. ambrosioides por hidrodestilación, la composición química volátil se determinó mediante cromatografía de gases acoplada a espectrometría de masas. El ensayo de actividad fumigante del aceite esencial se realizó sobre Sitophilus zeamais. La actividad antifúngica sobre el hongo fitopatógeno Fusarium oxysporum f. sp. Dianthi, y la capacidad antioxidante se efectuómediante el ensayo de decoloración del radical DPPH. Resultados: el compuesto mayoritario encontrado en aceite esencial de C. ambrosioides fue a-terpineno (60,29 %), seguido de p-cimeno (20,49 %), 4-careno (7,96 %) y trans-ascaridol (1,91 %). C. ambrosioides fue activo contra Fusarium oxysporum con un porcentaje de inhibición micelar de 97,3 % a 176,5 µL de aceite esencial/litro de aire, leído a las 72 h; y un porcentaje de mortalidad contra Sitophilus zeamais de 100 % a 500 µL de aceite esencial/litro de aire, después de 24 h de exposición. El porcentaje de inhibición del radical DPPH• fue de 84,89 %. Conclusiones: el aceite esencial de C. ambrosioides exhibió importante actividad fungicida contra F. oxysporum y fumigante contra S. zeamais, por lo cual podría reemplazar fungicidas e insecticidas sintéticos.