908 resultados para aristolan-8-en-1-one
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Quantitative data on lower marine Phycomycetes (fungi) found in the upwelling waters off the West African coast during cruises No. 13 (1968), 19 (1970), 36 (1975) and 44 (1977) of R.V. "Meteor" are reported. The distribution of the total fungi numbers is presented and, as far as possible, the evaluation of the material up to species level is given. Several provisionally named forms and groups of morphologically related, undescribed fungi are included. A correlation between the number of fungi in sediments and the water depth and distance from the coast line is postulated. There are typical distributions of the lower marine fungi in water bodies and sediments. Different values within replicates of the stations in different years show that there is a sequence in development of fungal populations induced by changes in the water bodies. Surface water far from the coast has low numbers of fungi; numbers increase to a maximum nearer to the coast. In the vicinity of the coast the values decrease. The numbers of fungi in the deep sediments are low below 1,200 m. However, there are isolated areas of higher fungal activities, indicated by some deeper grab samples. During two cruises, the "overlying water" in the grab samples was investigated. It was evident that the numbers of fungi lost by stirring of the sediment when the grab was brought up to the surface were small, relatively and absolutely. The seamount "Josephine Bank" has been investigated for the first time with respect to lower marine fungi; the populations are low in the sediments, but one sample of the surface water had a higher number than the water in the surroundings. In some hydrographic series there was a peculiar depth distribution. An increase occurred at a depth greater than 1,000 m. The results are discussed and some correlations to the aging of the fungal populations in the water masses are constructed.
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Over 300 surface sediment samples from the Central and South Atlantic Ocean and the Caribbean Sea were investigated for the preservation state of the aragonitic test of Limacina inflata. Results are displayed in spatial distribution maps and are plotted against cross-sections of vertical water mass configurations, illustrating the relationship between preservation state, saturation state of the overlying waters, and overall water mass distribution. The microscopic investigation of L. inflata (adults) yielded the Limacina dissolution index (LDX), and revealed three regional dissolution patterns. In the western Atlantic Ocean, sedimentary preservation states correspond to saturation states in the overlying waters. Poor preservation is found within intermediate water masses of southern origin (i.e. Antarctic intermediate water (AAIW), upper circumpolar water (UCDW)), which are distinctly aragonite-corrosive, whereas good preservation is observed within the surface waters above and within the upper North Atlantic deep water (UNADW) beneath the AAIW. In the eastern Atlantic Ocean, in particular along the African continental margin, the LDX fails in most cases (i.e. less than 10 tests of L. inflata per sample were found). This is most probably due to extensive "metabolic" aragonite dissolution at the sediment-water interface combined with a reduced abundance of L. inflata in the surface waters. In the Caribbean Sea, a more complex preservation pattern is observed because of the interaction between different water masses, which invade the Caribbean basins through several channels, and varying input of bank-derived fine aragonite and magnesian calcite material. The solubility of aragonite increases with increasing pressure, but aragonite dissolution in the sediments does not simply increase with water depth. Worse preservation is found in intermediate water depths following an S-shaped curve. As a result, two aragonite lysoclines are observed, one above the other. In four depth transects, we show that the western Atlantic and Caribbean LDX records resemble surficial calcium carbonate data and delta13C and carbonate ion concentration profiles in the water column. Moreover, preservation of L. inflata within AAIW and UCDW improves significantly to the north, whereas carbonate corrosiveness diminishes due to increased mixing of AAIW and UNADW. The close relationship between LDX values and aragonite contents in the sediments shows much promise for the quantification of the aragonite loss under the influence of different water masses. LDX failure and uncertainties may be attributed to (1) aragonite dissolution due to bottom water corrosiveness, (2) aragonite dissolution due to additional CO2 release into the bottom water by the degradation of organic matter based on an enhanced supply of organic matter into the sediment, (3) variations in the distribution of L. inflata and hence a lack of supply into the sediment, (4) dilution of the sediments and hence a lack of tests of L. inflata, or (5) redeposition of sediment particles.
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MTSD 0423.
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"Apéndices" de p. 293 a 427, texto en latín. Parte del texto a dos col. Anteportada.
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Texto a dos columnas. Anteportada.
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Mode of access: Internet.
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The endothelium is the primary barrier to leukocyte recruitment at sites of inflammation. Neutrophil recruitment is directed by transendothelial gradients of IL-8 that, in vivo, are bound to the endothelial cell surface. We have investigated the identity and function of the binding site(s) in an in vitro model of neutrophil transendothelial migration. In endothelial culture supernatants, IL-8 was detected in a trimolecular complex with heparan sulfate and syndecan-1. Constitutive shedding of IL-8 in this form was increased in the presence of a neutralizing Ab to plasminogen activator inhibitor-1 (PAI-1), indicating a role for endothelial plasminogen activator in the shedding of IL-8. Increased shedding of IL-8/heparan sulfate/syndecan-1 complexes was accompanied by inhibition of neutrophil transendothelial migration, and aprotinin, a potent plasmin inhibitor, reversed this inhibition. Platelets, added as an exogenous source of PAI-1, had no effect on shedding of the complexes or neutrophil migration. Our results indicate that IL-8 is immobilized on the endothelial cell surface through binding to syndecan-1 ectodomains, and that plasmin, generated by endothelial plasminogen activator, induces the shedding of this form of IL-8. PAI-1 appears to stabilize the chemoattractant form of IL-8 at the cell surface and may represent a therapeutic target for novel anti-inflammatory strategies.
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ACM Computing Classification System (1998): D.2.11, D.1.3, D.3.1, J.3, C.2.4.
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Chemical analyses of manganese nodules from the Central Pacific Basin show that their chemical composition varies regionally, although that of the associated sediments is markedly uniform throughout the basin. Mn content varies from 16 to 32% in average. Its higher value is generally found in nodules from siliceous clay and a few from deep-sea clay. Fe content tends to enrich in nodules from deep-sea clay area. Most manganese nodules, except those from deep-sea clay, are remarkably depleted in Fe compared with ones from the other Pacific regions. Mostly, Cu and Ni contents exceed 1% in nodules from siliceous clay, and decrease towards the northwest of the basin where deep-sea clay is distributed. The inter-element relationship between manganese nodules and associated sediments suggests that the mechanism of incorporation of major and minor elements in nodules is apparently different from that of the associated sediments. This finding seems to provide a new interpretation on the problem why manganese nodules having low accumulation rate are not buried by the associated sediments with greater sedimentation rate and then occur on sediment-seawater interface.
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The development and progression of odontogenic tumors have been associated with an imbalance in the activity of growth factors, adhesion molecules, extracellular matrix proteins and their degradation enzymes, angiogenic factors and osteolytic. Some studies have shown that interaction relationships inductive epithelial / mesenchymal determinants of Odontogenesis are mimicked by these tumors. The objective of this research was to investigate the immunolocalization of growth factors (BMP-4 and FGF-8) and Sindecan-1 structural protein in a series of odontogenic tumors presenting different biological behaviors, to contribute to a better understanding of the role of these proteins in tumor development. The sample consisted of 21 of the solid ameloblastoma, odontogenic keratocysts 19 and 14 odontogenic adenomatoid tumors. Increased Sindecan-1 immunostaining was seen in the epithelium of the lesions when compared with mesenchyme. In ameloblastoma and odontogenic keratocysts, this expression was higher than in AOT. Epithelial expression of BMP4 showed quantitatively similar in the three studied lesions; however, when anlisada mesenchymal immunoreactivity, was detected significant higher expression when compared to the ameloblastoma keratocysts. In ameloblastoma, mesenchymal expression was predominantly (p = 0.008), while in keratocyst higher expression in the epithelium was observed (p = 0.046). In all injuries, strong or moderate correlation was observed in the BMP-4 immunoreactivity in the epithelium and mesenchyme. FGF-8, no injury was observed difference between the immunoreactivity in the epithelium or mesenchyme, however in ameloblastoma positive correlation was found (Spearman correlation, rho = 0.857, p <0.001). The results of this study suggest that the three evaluated biomarkers actively involved in the pathogenesis of lesions, especially the expression of ameloblastomas indicating a strong interaction between parenchymal and stromal cells which may contribute to its marked aggressiveness.
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Planktic foraminifers Neogloboquadrina pachyderma (sin.) from 87 eastern and central Arctic Ocean surface sediment samples were analyzed for stable oxygen and carbon isotope composition. Additional results from 52 stations were taken from the literature. The lateral distribution of delta18O (18O/16O) values in the Arctic Ocean reveals a pattern of roughly parallel, W-E stretching zones in the Eurasian Basin, each ~0.5 per mil wide on the delta18O scale. The low horizontal and vertical temperature variability in the Arctic halocline waters (0-100 m) suggests only little influence of temperature on the oxygen isotope distribution of N. pachyderma (sin.). The zone of maximum delta18O values of up to 3.8 per mil is situated in the southern Nansen Basin and relates to the tongue of saline (> 33%.) Atlantic waters entering the Arctic Ocean through the Fram Strait. delta18O values decrease both to the Barents Shelf and to the North Pole, in accordance with the decreasing salinities of the halocline waters. In the Nansen Basin, a strong N-S delta18O gradient is in contrast with a relatively low salinity change and suggests contributions from different freshwater sources, i.e. salinity reduction from sea ice meltwater in the south and from light isotope waters (meteoric precipitation and river-runoff) in the northern part of the basin. North of the Gakkel Ridge, delta18O and salinity gradients are in good accordance and suggest less influence of sea ice melting processes. The delta13C (13C/12C) values of N. pachyderma (sin.) from Arctic Ocean surface sediment samples are generally high (0.75-0.95 per mil). Lower values in the southern Eurasian Basin appear to be related to the intrusion of Atlantic waters. The high delta13C values are evidence for well ventilated surface waters. Because the perennial Arctic sea ice cover largely prevents atmosphere-ocean gas exchange, ventilation on the seasonally open shelves must be of major importance. Lack of delta13C gradients along the main routes of the ice drift from the Siberian shelves to the Fram Strait suggests that primary production (i.e. CO2 consumption) does probably not change the CO2 budget of the Arctic Ocean significantly.
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Based on the quantitative analysis of diatom assemblages preserved in 274 surface sediment samples recovered in the Pacific, Atlantic and western Indian sectors of the Southern Ocean we have defined a new reference database for quantitative estimation of late-middle Pleistocene Antarctic sea ice fields using the transfer function technique. The Detrended Canonical Analysis (DCA) of the diatom data set points to a unimodal distribution of the diatom assemblages. Canonical Correspondence Analysis (CCA) indicates that winter sea ice (WSI) but also summer sea surface temperature (SSST) represent the most prominent environmental variables that control the spatial species distribution. To test the applicability of transfer functions for sea ice reconstruction in terms of concentration and occurrence probability we applied four different methods, the Imbrie and Kipp Method (IKM), the Modern Analog Technique (MAT), Weighted Averaging (WA), and Weighted Averaging Partial Least Squares (WAPLS), using logarithm-transformed diatom data and satellite-derived (1981-2010) sea ice data as a reference. The best performance for IKM results was obtained using a subset of 172 samples with 28 diatom taxa/taxa groups, quadratic regression and a three-factor model (IKM-D172/28/3q) resulting in root mean square errors of prediction (RMSEP) of 7.27% and 11.4% for WSI and summer sea ice (SSI) concentration, respectively. MAT estimates were calculated with different numbers of analogs (4, 6) using a 274-sample/28-taxa reference data set (MAT-D274/28/4an, -6an) resulting in RMSEP's ranging from 5.52% (4an) to 5.91% (6an) for WSI as well as 8.93% (4an) to 9.05% (6an) for SSI. WA and WAPLS performed less well with the D274 data set, compared to MAT, achieving WSI concentration RMSEP's of 9.91% with WA and 11.29% with WAPLS, recommending the use of IKM and MAT. The application of IKM and MAT to surface sediment data revealed strong relations to the satellite-derived winter and summer sea ice field. Sea ice reconstructions performed on an Atlantic- and a Pacific Southern Ocean sediment core, both documenting sea ice variability over the past 150,000 years (MIS 1 - MIS 6), resulted in similar glacial/interglacial trends of IKM and MAT-based sea-ice estimates. On the average, however, IKM estimates display smaller WSI and slightly higher SSI concentration and probability at lower variability in comparison with MAT. This pattern is a result of different estimation techniques with integration of WSI and SSI signals in one single factor assemblage by applying IKM and selecting specific single samples, thus keeping close to the original diatom database and included variability, by MAT. In contrast to the estimation of WSI, reconstructions of past SSI variability remains weaker. Combined with diatom-based estimates, the abundance and flux pattern of biogenic opal represents an additional indication for the WSI and SSI extent.
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Objetivos: Este estudio tuvo como objetivo elaborar un recuento y caracterizar a la población sin hogar de la ciudad de Coimbra. Se quería conocer quiénes son las personas sin hogar en Coimbra, sus características sociodemográficas, características psicosociales, síntomas depresivos, sentido de la vida y percepción de apoyo social, para disponer de un mayor conocimiento de su situación y necesidades y así mejorar la intervención social orientada al sinhogarismo. Método: El trabajo empírico realizado incluyó dos procedimientos simultáneos: (a) Un recuento de personas sin hogar, durante 3 días, en las instituciones especializadas de apoyo social y en las calles. (b) Una caracterización psicosocial a través de una entrevista estructurada a partir de los cuatro instrumentos siguientes: Cuestionario de Realojamiento y Evaluación (RTAS), Escala de Depresión del Centro para Estudios Epidemiológicos (CES-D), Cuestionario del sentido de la vida (PIL-R) y Cuestionario de Apoyo Social Percibido (CASP). Los datos fueron analizados mediante los programas SPSS, versión 18.0 y AMOS, versión 18.0. El recuento de personas sin hogar se realizó siguiendo la tipología Europea creada por FEANTSA, llamada ETHOS (European Typology on Homelessness and Housing Exclusion). Partiendo de esta tipología, en el recuento fueron identificadas 257 personas sin hogar, 175 de las cuales accedieron a ser entrevistadas, resultando válidas 174 entrevistas. Resultados: Verificamos que la mayoría de las personas sin hogar de nuestro estudio son hombres de menos de 50 años (edad media 46 años), portugueses, nacidos o con residencia en Coimbra hace más de un año, con escasos estudios, y que están solteros o divorciados. La mayoría duerme en instituciones (28,1%), vive en cuartos alquilados (23,6%) o en la calle (12,6%); han consumido drogas o alcohol (50%) y presentan problemas de salud mental (21,8%). En cuanto a ingresos, la mayoría percibe una renta mínima de inserción (37,9%) o se dedica a la mendicidad (17,2%). En cuanto a las causas percibidas de su situación de personas sin hogar, la mayoría apunta al desempleo (35%) y la pobreza (25,3%)...
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Un porcentaje no desdeñable de mujeres jóvenes con cáncer de mama esporádico son portadoras de mutaciones germinales en BRCA1/2. Esta prevalencia está estrechamente condicionada por otras variables como el tipo de población, fenotipo tumoral y edad de diagnóstico de cáncer de mama. La presencia de una estructura familiar no informativa es una variable predictiva de la presencia de mutaciones en BRCA1/2 en estas pacientes, pero este hallazgo no ha sido debidamente validado en cohortes independientes. Existe una fuerte asociación entre las mutaciones en BRCA1 y los tumores mamarios de tipo triple negativo (TN). En el presente trabajo analizamos la utilidad de las variables estructura familiar no informativa y fenotipo TN como variables predictivas de mutaciones germinales en BRCA1/2 en una cohorte de mujeres jóvenes ( 35 años) con cáncer de mama esporádico previamente remitidas (1998-2012) a unidades de asesoramiento genético españolas (n = 341). Retrospectivamente, la estructura familiar fue clasificada en informativa, no informativa o no clasificable mediante la revisión centralizada de los pedigrees disponibles en el momento de realizarse los respectivos estudios genéticos. Asimismo, los tumores de mama fueron clasificados en TN, no-TN y no clasificables mediante la revisión de las historias clínicas. Veinticuatro pacientes (7.12 %) fueron portadoras de mutaciones patogénicas, 14 en BRCA1 y 10 en BRCA2. Tanto la estructura familiar no informativa (OR = 3.61, p = 0.027) como el subtipo TN (OR = 3.14, p = 0.013) fueron variables independientes de la presencia de mutaciones germinales en BRCA1/2. La prevalencia de mutaciones en el subgrupo de mujeres con al menos un factor predictivo (estructura familiar no informativa, subtipo TN o ambos) fue del 13.5 %, frente al 2.8 % en aquellas mujeres con estrucutra familiar informativa y tumores no-TN (OR = 5.31, p = 0.006). Demostramos, con la información disponible en un contexto de práctica clínica rutinaria, la utilidad de la estructura familiar y el fenotipo TN como modelo predictivo de mutaciones germinales en BRCA1/2 en mujeres jóvenes con cáncer de mama esporádico. Nuestro estudio sugiere que restringir el análisis tan solo a aquellas mujeres con al menos un factor predicitivo podría ser una estrategia válida para optimizar la realización de estudios genéticos en este subgrupo de mujeres.
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Objective. This study aims to provide a better understanding of the amounts spent on different malaria prevention products and the determinants of these expenditures. Methods. 1,601 households were interviewed about their expenditure on malaria mosquito nets in the past five years, net re-treatments in the past six months and other expenditures prevention in the past two weeks. Simple random sampling was used to select villages and streets while convenience sampling was used to select households. Expenditure was compared across bed nets, aerosols, coils, indoor spraying, using smoke, drinking herbs and cleaning outside environment. Findings. 68% of households owned at least one bed net and 27% had treated their nets in the past six months. 29% were unable to afford a net. Every fortnight, households spent an average of US $0.18 on nets and their treatment, constituting about 47% of total prevention expenditure. Sprays, repellents and coils made up 50% of total fortnightly expenditure (US$0.21). Factors positively related to expenditure were household wealth, years of education of household head, household head being married and rainy season. Poor quality roads and living in a rural area had a negative impact on expenditure. Conclusion. Expenditure on bed nets and on alternative malaria prevention products was comparable. Poor households living in rural areas spend significantly less on all forms of malaria prevention compared to their richer counterparts. Breaking the cycle between malaria and poverty is one of the biggest challenges facing malaria control programmes in Africa.