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1.
Chemosphere ; 223: 223-231, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30784729

RESUMO

Trace element (TE)-contaminated soils require the improvement of their physico-chemical properties in order to allow their restoration through phytostabilization technologies. This study aimed to determine the usefulness of oxidative stress related parameters to validate the suitability of two different combinations of organic (solid fraction of pig slurry) and inorganic (paper mill sludge or a commercial red mud derivative) amendments for the phytostabilization of an acidic (4.2) TE-contaminated mine soil from SE Spain. Two wild species (Silybum marianum and Piptatherum miliaceum) were greenhouse cultivated and the development of the plants, their ionome, and oxidative stress related parameters were determined. Both amendment combinations increased significantly soil pH (to 5-6) and soil/pore water total organic C and total N concentrations, allowing an adequate plant growth and development (plants did not grow in untreated soils). The combination of amendments significantly reduced metal availability and showed to be effective (specially the one including the red mud derivative) in limiting shoot TE concentrations, which were all within common ranges (exclusion based tolerance of these species). Both protein carbonylation and lipid peroxidation were significantly higher in S. marianum plants from phytostabilized soils than in those from non-contaminated soils, which confirms the oxidative stress these plants suffer despite their satisfactory growth in the treated soils. P. miliaceum plants showed no differences between phytostabilized and non-contaminated soils. Therefore, the combination of amendments and TE-tolerant autochthonous species would be a suitable option for the phytostabilisation of soils contaminated by mining activities, reducing TE solubility and allowing an adequate plant growth.


Assuntos
Mineração , Estresse Oxidativo/efeitos dos fármacos , Desenvolvimento Vegetal/efeitos dos fármacos , Solo/química , Oligoelementos/efeitos adversos , Animais , Compostos Inorgânicos/farmacologia , Compostos Orgânicos/farmacologia , Plantas/metabolismo , Poluentes do Solo/análise , Espanha , Suínos
2.
Rev. colomb. enferm ; 16(1): 43-51, Abril de 2018.
Artigo em Espanhol | LILACS, BDENF - Enfermagem, COLNAL | ID: biblio-987997

RESUMO

Introducción: la autoeficacia es una habilidad social que parte de la disposición del individuo para enfrentar las situaciones\r\nestresantes del medio en el que se desenvuelve; se plantea como una herramienta que es necesario fortalecer en los programas\r\nde salud sexual y reproductiva para prevenir embarazos no planeados en la adolescencia. Objetivo: determinar la diferencia en\r\nla autoeficacia entre adolescentes gestantes y no gestantes de 15 a 19 años, a partir de la escala de autoeficacia general. Metodología:\r\ninvestigación cuantitativa comparativa de corte transversal, con una muestra de 60 adolescentes gestantes y 60 no\r\ngestantes, habitantes de una localidad del sur de Bogotá, Colombia. El análisis de datos se realizó con pruebas estadísticas no\r\nparamétricas. Resultados: se encontró que no existe una diferencia estadísticamente significativa en la autoeficacia entre los\r\ngrupos comparados y no se encontró relación entre la autoeficacia y el antecedente de haber sido hija de una madre adolescente.\r\nSin embargo, las adolescentes gestantes presentaron en mayor porcentaje el antecedente de haber sido hijas de madres adolescentes. Conclusiones: la investigación no mostró diferencia en la autoeficacia entre los dos grupos comparados, lo cual se relaciona con las características sociales y económicas similares de la población participante. Recomendaciones: investigar la relación del embarazo no planeado en la adolescencia con la autoeficacia y otras habilidades sociales, como la autoestima, en poblaciones con características socioeconómicas diferentes.


Introduction: Self-efficacy is a social skill that starts from the personal disposition to face the stressful situations of the environment in which the individual develops. It is considered a tool to be strengthened in sexual and reproductive health programs for the planned prevention of pregnancy in adolescence. Objective: To determine the difference in self-efficacy between pregnant and non-pregnant adolescents ages 15 to 19 using the scale of general self-efficacy. Methodology: A cross-sectional quantitative research was performed, in 60 pregnant adolescents and 60 non-pregnant adolescents, all residents of the south side of Bogotá, Colombia. The data analysis was performed with nonparametric statistical tests. Results: There was no significant statistical difference in the self-efficacy between the groups and the antecedent of having been the daughter of a teenage mother. However, the pregnant adolescents presented a higher percentage of having been daughters of adolescent mothers. Conclusions: The research showed no difference in self-efficacy between the two groups; this is related to the similar social and economic characteristics of the participating population. Recommendations: Investigate the relationship of unplanned pregnancy in adolescence with self-efficacy and other social skills such as self-esteem in populations with different socioeconomic characteristics.


Introdução: a autoeficácia é uma habilidade social que parte da vontade pessoal de enfrentar situações estressantes do meio em que se vive e, portanto, surge como uma ferramenta para fortalecer os programas de saúde sexual e reprodutiva para a prevenção da gravidez não planejada na adolescência. Objetivo: determinar a diferença na eficácia entre adolescentes grávidas e não grávidas com idades entre 15 a 19 anos usando como base a escala geral de autoeficácia. Metodologia: um estudo transversal quantitativo comparativo com uma amostra de 60 adolescentes grávidas e 60 adolescentes não grávidas, habitantes de uma cidade no sul de Bogotá, na Colômbia. A análise de dados foi realizada com testes estatísticos não paramétricos. Resultados: descobriu-se que não há diferença estatisticamente significativa na autoeficácia entre os dois grupos em comparação e entre a autoeficácia e ter como antecedente mãe que engravidou na adolescência. Porém, as adolescentes gestantes com mães adolescentes como antecedente apresentaram maior porcentagem. Conclusões: o estudo não apresentou diferença na autoeficácia entre os dois grupos comparados, adolescentes grávidas e adolescentes não grávidas, isso pode estar relacionado às características sociais e econômicas da população participante, portanto, podemos dizer que a autoeficácia nesta pesquisa não está relacionada com a decisão de gravidez na adolescência. Recomendações: investigar a relação de gravidez não planejada na adolescência com autoeficácia e outras habilidades sociais, como a autoestima em populações com diferentes características socioeconômicas.


Assuntos
Gravidez na Adolescência , Autoeficácia , Saúde Reprodutiva
3.
Chemosphere ; 178: 556-564, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28351014

RESUMO

Phytostabilisation strategies have proven to be an efficient remediation option for mine tailings, but the adequate plant species and amendments have to be carefully selected. A remediation experiment was carried out at the semi-field level in tailings (pH 3.2, ≈1100, 4700 and 5000 mg kg-1 of As, Pb and Zn, respectively) from the mining district of La Unión-Cartagena (SE Spain). A red mud derivative (Fe/Al oxides), its combination with compost, and hydrated lime (Ca hydroxide) were applied in field plots of 0.25 m2. After four months of field stabilisation, tailings were transferred unaltered to a plant growth facility, and Atriplex halimus and Zygophyllum fabago (halophytes) were sown. Three months later, trace element (TE) solubility, plant accumulation and chemical speciation in the tailings pore water were studied. In unamended tailings, soluble TEs concentrations were very high (e.g., 40 mg Zn l-1), the dominant species being free ions and SO42-- complexes (>70%). The addition of amendments increased tailings pH (6.7-7), reduced TEs solubility and extractability (>80-99%) and changed the dominant species of soluble Al, Cu, Pb and Zn to hydroxides and/or organo-metallic complexes, but increased slightly the extractable As and soluble Tl concentrations. Plants were able to grow only in amended tailings, and both species presented low levels of Al, As, Cd and Zn. Therefore, the use of combined red mud derivative and compost and halophytes was shown to be a good phytostabilisation strategy, although the dose applied must be carefully chosen in order to avoid possible solubilisation of As and Tl.


Assuntos
Recuperação e Remediação Ambiental/métodos , Metais Pesados/análise , Mineração , Desenvolvimento Vegetal/efeitos dos fármacos , Poluentes do Solo/análise , Compostos de Cálcio , Monitoramento Ambiental/métodos , Metais Pesados/isolamento & purificação , Metais Pesados/farmacologia , Óxidos , Solo/química , Poluentes do Solo/isolamento & purificação , Poluentes do Solo/farmacologia , Espanha
4.
Rev. chil. enferm. respir ; 32(4): 224-232, dic. 2016. graf, tab
Artigo em Espanhol | LILACS | ID: biblio-844386

RESUMO

Objective: To assess the performance of multiplex-PCR for diagnosis of respiratory viruses in parallel with direct fluorescence assay (DFA). We assessed the performance and co-infection diagnosis of molecular respiratory panel PCR (MRP-PCR) and DFA in hospitalized and outpatients. Results: 8535 samples were included, 1792 tested by MRP-PCR (46.9% positive) and 6743 by DFA (35.1% positive). MRP-PCR diagnosed co-infection in 21.3% and DFA in 1.8% of the samples. Rhinovirus was the most common virus in any age group. In 210 patients both tests were done; 100 were positive by MRP-PCR and 18 by DFA. Positive concordance value was 6.2%. 85 samples were positive only by MRP-PCR and in 42 of them only novel respiratory viruses were identified. Performance of MRP-PCR was statistically significant compared DFA for traditional respiratory viruses. Discussion: Multiplex PCR has shown better sensitivity, may expand the etiologic spectrum of respiratory infections and detect a higher number of co-infections.


Objetivo: Evaluar la contribución del panel respiratorio molecular por reacción en cadena de la polimerasa-multiplex (PRM-RPC) en paralelo a la de inmunofluorescencia directa (IFD) al diagnóstico de infecciones respiratorias. Analizamos y comparamos el rendimiento y diagnóstico de co-infección de PRM-RPC con IFD en pacientes hospitalizados y ambulatorios. Resultados: Se analizaron 8535 muestras; 1792 por PRM-RPC (46,9% positivas) y 6743 por IFD (35,1% positivas). La co-infección fue 21,3% por PRM-RCP y 1,8% por IFD. El virus más frecuente fue rinovirus a toda edad. Se analizaron 210 pacientes por ambos métodos; resultaron positivas 100 por PRM-RPC y 18 por IFD, concordancia positiva de 6,2%. 85 muestras fueron solo positivas por PRM-RPC, 42 diagnosticaron nuevos virus respiratorios. El rendimiento de PRM-RPC fue significativamente mayor que el de IFD para virus respiratorios tradicionalmente diagnosticados. Conclusiones: La RCP-multiplex tiene mejor sensibilidad, podría expandir el espectro etiológico de infecciones respiratorias y detectar un mayor número de co-infecciones comparado a IFD.


Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Lactente , Pré-Escolar , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Adulto Jovem , Técnica Direta de Fluorescência para Anticorpo , Reação em Cadeia da Polimerase Multiplex , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/microbiologia , Doença Aguda , Distribuição por Idade , Técnicas de Diagnóstico Molecular , Infecções Respiratórias/virologia , Estações do Ano
5.
Chemosphere ; 107: 101-108, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24875876

RESUMO

The feasibility of two organic materials (pig slurry and compost) in combination with hydrated lime for the remediation of a highly acidic trace elements (TEs) contaminated mine soil was assessed in a mesocosm experiment. The effects of the amendments on soil biochemical and ecotoxicological properties were evaluated and related with the main physicochemical characteristics of soil and soil solution. The original soil showed impaired basic ecological functions due to the high availability of TEs, its acidic pH and high salinity. The three amendments slightly reduced the direct and indirect soil toxicity to plants, invertebrates and microorganisms as a consequence of the TEs' mobility decrease in topsoil, reducing therefore the soil associated risks. The organic amendments, especially compost, thanks to the supply of essential nutrients, were able to improve soil health, as they stimulated plant growth and significantly increased enzyme activities related with the key nutrients in soil. Therefore, the use of compost or pig slurry, in combination with hydrated lime, decreased soil ecotoxicity and seems to be a suitable management strategy for the remediation of highly acidic TEs contaminated soils.


Assuntos
Compostos de Cálcio/farmacologia , Ecotoxicologia , Esterco , Mineração , Óxidos/farmacologia , Solo/química , Fosfatase Ácida/metabolismo , Animais , Biodegradação Ambiental/efeitos dos fármacos , Bioensaio , Compostos de Cálcio/química , Fenômenos Químicos , Fertilizantes , Oligoquetos/efeitos dos fármacos , Óxidos/química , Poluentes do Solo/isolamento & purificação , Poluentes do Solo/metabolismo , Poluentes do Solo/toxicidade , Suínos , beta-Glucosidase/metabolismo
6.
Chemosphere ; 107: 121-128, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24875879

RESUMO

A mesocosm experiment, in columns, was conducted in a growth chamber to assess the viability of two organic materials (pig slurry and compost; in combination with hydrated lime) for the remediation of a highly acidic and trace elements (TEs) contaminated mine soil and the reduction of its associated leaching risks. Their influence on the evolution throughout the soil depth of the physicochemical properties (including TEs mobility) of the soil and soil solution (in situ periodic collection) and on Lolium perenne growth and foliar TEs accumulation was evaluated. Soluble and extractable concentrations of the different TEs were considerably high, although the organic amendments (with lime) and lime addition successfully decreased TEs mobility in the top soil layer, as a consequence of a rise in pH and changes in the redox conditions. Compost and pig slurry increased the soluble organic-C and dissolved N, K and P of the soil, producing a certain downwards displacement of N and K. The organic amendments allowed the growth of L. perenne in the soil, thus indicating improvement of soil conditions, but elevated TEs availability in the soil led to toxicity symptoms and abnormally high TEs concentrations in the plants. An evaluation of the functioning and ecotoxicological risks of the remediated soils is reported in part II: this allows verification of the viability of the amendments for remediation strategies.


Assuntos
Compostos de Cálcio/farmacologia , Fertilizantes , Esterco , Mineração , Óxidos/farmacologia , Solo/química , Animais , Biodegradação Ambiental/efeitos dos fármacos , Transporte Biológico/efeitos dos fármacos , Compostos de Cálcio/química , Concentração de Íons de Hidrogênio , Lolium/efeitos dos fármacos , Lolium/metabolismo , Óxidos/química , Porosidade , Risco , Poluentes do Solo/química , Poluentes do Solo/isolamento & purificação , Poluentes do Solo/metabolismo , Solubilidade , Suínos , Água/química
7.
J Hazard Mater ; 268: 68-76, 2014 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-24468528

RESUMO

The efficiency of a remediation strategy was evaluated in a mine soil highly contaminated with trace elements (TEs) by microbiological, ecotoxicological and physicochemical parameters of the soil and soil solution (extracted in situ), as a novel and integrative methodology for assessing recovery of soil health. A 2.5-year field phytostabilisation experiment was carried out using olive mill-waste compost, pig slurry and hydrated lime as amendments, and a native halophytic shrub (Atriplex halimus L.). Comparing with non-treated soil, the addition of the amendments increased soil pH and reduced TEs availability, favoured the development of a sustainable vegetation cover (especially the organic materials), stimulated soil microorganisms (increasing microbial biomass, activity and functional diversity, and reducing stress) and reduced direct and indirect soil toxicity (i.e., its potential associated risks). Therefore, under semi-arid conditions, the use of compost and pig slurry with A. halimus is an effective phytostabilisation strategy to improve soil health of nutrient-poor soils with high TEs concentrations, by improving the habitat function of the soil ecosystem, the reactivation of the biogeochemical cycles of essential nutrients, and the reduction of TEs dissemination and their environmental impact.


Assuntos
Atriplex/crescimento & desenvolvimento , Biodegradação Ambiental , Poluentes do Solo/isolamento & purificação , Solo/química , Oligoelementos/isolamento & purificação , Biomassa , Fertilizantes , Microbiologia do Solo
8.
Rev. chil. pediatr ; 84(2): 145-151, abr. 2013. tab
Artigo em Espanhol | LILACS | ID: lil-687170

RESUMO

Objetivo: Comparar la prevalencia de ronquido habitual como síntoma cardinal de los trastornos respiratorios del sueño (TRS) en población escolar de dos comunas de Santiago, de diferente nivel socioeconómico y exposición a contaminación ambiental. Métodos: Estudio transversal, de tipo ecológico. Se aplicó un cuestionario de sueño a los padres de escolares de 1° básico a 3°medio matriculados en dos colegios ubicados en las comunas de Puente Alto (zona sur oriente, colegio subvencionado) y Providencia (zona oriente, colegio particular). Los datos de contaminación ambiental se obtuvieron a partir del registro de estaciones de monitoreo. La caracterización socioeconómica comunal se realizó en base a fuentes ministeriales. Resultados: Los niveles de contaminación ambiental fueron mayores en el sector sur-oriente, comparado con el sector oriente de Santiago. Los indicadores comunales de nivel socioeconómico fueron superiores en la comuna de Providencia. La prevalencia de ronquido en escolares fue superior en el colegio ubicado en Puente Alto (18,2 por ciento; IC95 por ciento 14,0-21,6) en comparación al colegio ubicado en Providencia (0,7 por ciento; IC95 por ciento 0,1-2,4). Conclusión: La prevalencia de TRS fue diferente en las comunas estudiadas y podría estar atribuida a factores medioambientales y socioeconómicos. El presente estudio constituye un punto de partida para la realización de estudios de base individual.


Objective: To compare the prevalence of habitual snoring as cardinal symptom of sleep-disordered breathing (SDB) in schoolchildren from two communes of Santiago, presenting different levels of socioeconomic status and exposure to environmental pollution. Methods: Cross-sectional ecological study. A sleep questionnaire was administered to parents of primary school kids from 1st through 3rd grade, from two schools, one located in the district of Puente Alto (south-east, subsidized school) and the other in Providencia (east area, private school). Pollution data were obtained from monitoring stations. Socioeconomic characterization was performed based on government sources. Results: The levels of air pollution were higher in the south-east area, compared to the eastern sector of Santiago. Indicators of socioeconomic level were higher in the Providencia commune. The prevalence of snoring in students was higher in the school located in Puente Ailto (18.2 percent, 95 percent CI 14.0 to 21.6) compared to the school located in Providencia (0.7 percent, 95 percent CI 0.1 - 2.4). Conclusion: The prevalence of SDB was different in the communities studied and could be attributed to environmental and socioeconomic factors. This study is a starting point for further studies on individual basis.


Assuntos
Humanos , Adolescente , Criança , Poluição Ambiental/efeitos adversos , Síndromes da Apneia do Sono/epidemiologia , Chile , Estudos Transversais , Prevalência , Sons Respiratórios , Smog , Fatores Socioeconômicos , Inquéritos e Questionários
9.
Av. enferm ; 29(2): 294-306, jul.-dic. 2011. graf, tab
Artigo em Espanhol | LILACS, BDENF - Enfermagem, COLNAL | ID: lil-635415

RESUMO

Se describe lo que significa la sexualidad para la mujer gestante. Para tal fin se desarrolló un estudio con abordaje cualitativo, diseño etnográfico, soportado conceptualmente en la Teoría de la cultura de los cuidados: teoría de la diversidad y la universalidad, de Madeleine Leininger. Los datos se obtuvieron a través de entrevista semiestructurada, observación y notas de campo. La información aportada por las entrevistas se analizó utilizando el método etnográfico de James Spradley que permitió develar el tema general "Demostrar el amor: una necesidad que se vive, se siente, se expresa durante la gestación", constituido por tres subtemas con sus respectivos dominios: la protección (cuidarse y la normalidad), el miedo (tener relaciones sexuales, los cambios y tener sexo) y la satisfacción (ejercer la sexualidad, relacionarse con el esposo y estar bien). El aporte de esta investigación está dado por la interpretación del significado de la sexualidad para la gestante, desde lo cultural, la cual está sujeta a mitos y creencias que históricamente han acompañado tanto la gestación como la sexualidad en sí misma; se interpreta esta no solo como una necesidad para la continuidad de la vida, sino también como un aspecto esencial de convivencia y comunicación con otros seres humanos.


The research objective was to describe what sexuality means for pregnant women. To achieve the same was necessary to develop a qualitative study ethnographic design, conceptually supported the theory of Culture Care: A Theory of Diversity and Universality of Madeleine Leininger. Data were collected through semi-structured interviews, observation and field notes. The information provided by these interviews was analyzed using James Spradley ethnographic method enabled to reveal the general theme "Show love, a need that exists, he feels, is expressed during pregnancy", consisting of three sub-domains with their respective ; protection (care and normal), fear (sexual intercourse, and sex changes) and satisfaction (exercise sexuality, relationships with their husbands and be good). The contribution of this research is given by the interpretation of the meaning of sexuality for the pregnant woman from culture, which is subject to myths and beliefs that have historically accompanied both pregnancy and sexuality in itself, this is interpreted not only as a need for continuity of life, but also as an essential aspect of coexistence and communication with other human beings.


Osignificado da sexualidade para a mulher gestante é descrito. Para atingir esse objetivo, foi desenvolvido um estudo qualitativo, desenho etnográfico, baseado conceitualmente na Teoria da cultura de cuidado: teoria da diversidade e a universalidade, de Madeleine Leininger. Os dados foram obtidos através de entrevistas semi-estruturadas, da observação e de notas de campo. A informação obtida das entrevistas foi analisada pelo método etnográfico de James Spradley, permitindo expor o tema general: "Demonstrar o amor: uma necessidade que é vivida, é sentida, é exprimida durante a gestação", constituído por três sub-temas, com seus respectivos domínios: a proteção (cuidado e normalidade), o medo (ter relações sexuais, as mudanças e fazer sexo) e a satisfação (exercer a sexualidade, a relação com o marido e o bem-estar). A contribuição desta pesquisa vem dada pela interpretação do significado da sexualidade para a mulher gestante, desde o ponto de vista cultural, sujeita a mitos e crenças que acompanham historicamente tanto ao processo de gestação quanto à própria sexualidade. Este último elemento é interpretado não só como uma necessidade para a continuação da vida, mas também como um aspecto essencial da convivência e da comunicação entre os seres humanos.


Assuntos
Gravidez , Cônjuges , Sexualidade , Amor
11.
13.
Gastroenterol. latinoam ; 13(4): 281-285, sept. 2002. ilus
Artigo em Espanhol | LILACS | ID: lil-340183

RESUMO

El carcinoma adenoescamoso del colon es una rara neoplasia, cuya evolución es agresiva y el manejo difícil, debido a la escasa respuesta al tratamiento. Se presenta un caso que se inicia con sintomatología urinaria y después de hacer el estudio diagnóstico y el tratamiento adecuado, se encuentra con una pobre respuesta y rápido deterioro del paciente


Assuntos
Humanos , Masculino , Adulto , Carcinoma Adenoescamoso , Neoplasias do Colo , Metástase Neoplásica
14.
Chemistry ; 7(13): 2848-61, 2001 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-11486962

RESUMO

The reaction of 1,1'-ferrocene-bis(methylenepyridinium) salt with 1,4,8,11-tetraazacyclotetradecane-5,12-dione, followed by LiAlH4 reduction results in the formation of FcCyclam. Metal complexes of FcCyclam with M2+ = Co2+, Ni2+, Cu2+, and Zn2+ were synthesized from FcCyclam and the respective metal triflates. The complexation of Cu2+ and FcCyclam in CH3CN is preceeded by a rapid electron transfer, followed by a slower complex formation reaction and a reverse electron transfer. The protonation constants of FcCyclam and the stability constants for the Cu2+ complex of FcCyclam (logK = 9.26(4) for the formation of the [Cu(FcCyclam)]2+ complex) were determined in 1,4-dioxane/water 70:30 v/v, 0.1 moldm(-3), KNO3, 25 degrees C. By using FcCyclam one can selectively sense the presence of Cu2+ ions in the presence of Ni2+, Zn2+, Cd2+, Hg2+, and Pb2+ with a very large deltaE approximately 200 mV, depending on pH. The X-ray crystal structures of FcCyclam and of complexes with Co2+, Ni2+, Cu2+, and Zn2+ were determined and Fe-M2+ distances obtained: Fe-Co2+ 395.9, Fe-Ni2+ 385.4, Fe-Cu2+ 377.7, and Fe-Zn2+ 369.0 pm. The redox potential of FcCyclam is influenced in a characteristic manner by the complexation of M2+. A linear correlation of 1/r approximately/= deltaE [r = distance Fe-M2+ from crystal data, deltaE=-E1/2([M(FcCyclam)]2+) - E1/2(FcCyclam)] was found; this is indicative of a mainly Coulomb type interaction between the two metal centers. The nature of the Fe...M2+ interaction was also investigated by determining deltaE in several solvents (mixtures) of different dielectric constants epsilon. The expected relation of deltaE approximately/= 1/epsilon was only found at very high values of epsilon. At epsilon < 40 increased ion-pairing appears to reduce the effective positive charge at M2+ leading to progessively smaller values of deltaE with lowered epsilon. The dependence of deltaE and epsilon can be calculated semiquantitatively by combining the Fuoss ion-pairing theory with the Coulomb model.

15.
Rev. méd. Chile ; 129(3): 237-46, mar. 2001. tab, graf
Artigo em Espanhol | LILACS | ID: lil-286857

RESUMO

Background: Staging of colorectal carcinoma has prognostic value and allows to take decisions about adjuvant therapy and follow up. Prognostic factors are not universally accepted and there are different staging classifications. Aim: To assess the prognostic value of clinical and pathological variables in 224 patients subjected to a curative resection of a colorectal carcinoma. Patients and methods: A retrospective analysis of 99 men and 125 women, aged 23 to 91 years old subjected to a curative resection of a colorectal carcinoma and followed up for a mean of 72 months. Results: Global survival at 60 months was 72 percent . Univariate analysis showed that tumor localization, vascular permeation, wall infiltration and number of involved lymph nodes had an influence on survival. A Cox regression model disclosed tumor localization (colon versus rectum), a carcinoembrionic antigen over 30 ng/ml, vascular permeation, presence of 1 to 4 involved lymph nodes, or 5 or more lymph nodes and the presence of an apical lymph node as variables with significant prognostic value. Conclusions: Our series confirms the prognostic importance of lymph node involvement. This parameter is incorporated in Jass, GITSG (both modifications of Dukes classification) and TNM staging scores


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Neoplasias Colorretais/epidemiologia , Prognóstico , Neoplasias Colorretais/cirurgia , Estadiamento de Neoplasias , Análise Multivariada
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