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1.
Cell Death Dis ; 15(3): 223, 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38493149

RESUMO

Spalt-like proteins are Zinc finger transcription factors from Caenorhabditis elegans to vertebrates, with critical roles in development. In vertebrates, four paralogues have been identified (SALL1-4), and SALL2 is the family's most dissimilar member. SALL2 is required during brain and eye development. It is downregulated in cancer and acts as a tumor suppressor, promoting cell cycle arrest and cell death. Despite its critical functions, information about SALL2 regulation is scarce. Public data indicate that SALL2 is ubiquitinated and phosphorylated in several residues along the protein, but the mechanisms, biological consequences, and enzymes responsible for these modifications remain unknown. Bioinformatic analyses identified several putative phosphorylation sites for Casein Kinase II (CK2) located within a highly conserved C-terminal PEST degradation motif of SALL2. CK2 is a serine/threonine kinase that promotes cell proliferation and survival and is often hyperactivated in cancer. We demonstrated that CK2 phosphorylates SALL2 residues S763, T778, S802, and S806 and promotes SALL2 degradation by the proteasome. Accordingly, pharmacological inhibition of CK2 with Silmitasertib (CX-4945) restored endogenous SALL2 protein levels in SALL2-deficient breast MDA-MB-231, lung H1299, and colon SW480 cancer cells. Silmitasertib induced a methuosis-like phenotype and cell death in SW480 cells. However, the phenotype was significantly attenuated in CRISPr/Cas9-mediated SALL2 knockout SW480 cells. Similarly, Sall2-deficient tumor organoids were more resistant to Silmitasertib-induced cell death, confirming that SALL2 sensitizes cancer cells to CK2 inhibition. We identified a novel CK2-dependent mechanism for SALL2 regulation and provided new insights into the interplay between these two proteins and their role in cell survival and proliferation.


Assuntos
Caseína Quinase II , Neoplasias do Colo , Animais , Humanos , Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Neoplasias do Colo/genética , Linhagem Celular Tumoral
2.
Int. j. odontostomatol. (Print) ; 17(2): 130-135, jun. 2023. tab
Artigo em Espanhol | LILACS | ID: biblio-1440350

RESUMO

El cuerpo adiposo de la boca (CAB) es un componente adiposo multilobulado bien delimitado, localizado de manera bilateral en la región facial íntimamente relacionado a estructuras nerviosas y vasculares. La remoción de CAB es un procedimiento ampliamente estudiado en el campo de la cirugía maxilofacial, utilizado principalmente para cubrir defectos. Su influencia en la estética facial ha iniciado una popularización de la remoción de la extensión bucal de CAB para obtener un rostro más estilizado, intervención difundida como poco invasiva y sin complicaciones. El objetivo de este estudio fue recopilar y evaluar estudios que reporten y evalúen complicaciones asociadas a la remoción por razones estéticas de CAB. Se revisó la evidencia en las bases de datos Medline vía PubMed, Epistemonikos, Scopus y Google Scholar, utilizando términos predefinidos, seleccionando estudios primarios de reportes de casos. Se incluyeron 7 artículos con un total de 10 pacientes; de estos, ocho pacientes se realizaron este procedimiento en Brasil, uno en Estados Unidos y uno en Chile. La distribución de la población fue de 3:7 entre hombres y mujeres con edad promedio de 35 años y un rango entre los 23 a los 49 años. En relación a las complicaciones reportadas, 100 % de los pacientes presentaron asimetría facial, un 80 % presentó edema facial, 30 % manifestaron sialocele, Trismus 20 %, 40 % presentó hematoma, 20 % compromiso del estado general, 20 % presentaron disfagia, en los casos de hipoestesia, parestesia, absceso, seroma, parálisis facial, odinofagia, fiebre se expresaron en 10 % de la población estudiada. En todos los estudios se describió una reintervención quirúrgica posterior a la remoción estética del cuerpo adiposo de bichat. La escasa literatura y la baja calidad de esta, no permite estimar el porcentaje real de posibles complicaciones, tampoco es posible determinar sus resultados a largo plazo ya que no existe en la evidencia un seguimiento apropiado para estos pacientes.


The buccal adipose body (BAB) is a well- defined multilobulated adipose component, located bilaterally in the facial region, closely related to nervous and vascular structures. BAB removal is a widely studied procedure in the field of maxillofacial surgery, used mainly to cover defects. Its influence on facial aesthetics has started to popularize the removal of the BAB buccal extension to obtain a more stylized face, an intervention widely known as minimally invasive and without complications. The objective of this study was to collect and evaluate studies that report and evaluate complications associated with the removal of BAB for cosmetic reasons. The evidence was reviewed in the Medline databases via PubMed, Epistemonikos, Scopus, and Google Scholar, using predefined terms, selecting primary studies from case reports. 7 articles with a total of 10 patients were included; Of these, eight patients underwent this procedure in Brazil, one in the United States, and one in Chile. The distribution of the population was 3:7 between men and women with an average age of 35 years and a range between 23 to 49 years. In relation to the reported complications, 100 % of the patients presented facial asymmetry, 80 % presented facial edema, 30 % manifested sialocele, trismus 20 %, 40 % presented hematoma, 20 % compromised general state, 20 % presented dysphagia, in the cases of hypoesthesia, paresthesia, abscess, seroma, facial paralysis, odynophagia, fever were expressed in 10 % of the studied population. All the studies described a surgical reintervention after cosmetic removal of the bichat adipose body. The scarce literature and its low quality do not allow estimating the real percentage of possible complications, nor is it possible to determine their long-term results since there is no evidence of appropriate follow-up for these patients.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Tecido Adiposo/cirurgia , Procedimentos Cirúrgicos Bucais/efeitos adversos , Bochecha/cirurgia , Procedimentos de Cirurgia Plástica/efeitos adversos
3.
Vaccine ; 41(1): 251-262, 2023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36446653

RESUMO

BACKGROUND: In May 2020, the ACCESS (The vACCine covid-19 monitoring readinESS) project was launched to prepare real-world monitoring of COVID-19 vaccines. Within this project, this study aimed to generate background incidence rates of 41 adverse events of special interest (AESI) to contextualize potential safety signals detected following administration of COVID-19 vaccines. METHODS: A dynamic cohort study was conducted using a distributed data network of 10 healthcare databases from 7 European countries (Italy, Spain, Denmark, The Netherlands, Germany, France and United Kingdom) over the period 2017 to 2020. A common protocol (EUPAS37273), common data model, and common analytics programs were applied for syntactic, semantic and analytical harmonization. Incidence rates (IR) for each AESI and each database were calculated by age and sex by dividing the number of incident cases by the total person-time at risk. Age-standardized rates were pooled using random effect models according to the provenance of the events. FINDINGS: A total number of 63,456,074 individuals were included in the study, contributing to 211.7 million person-years. A clear age pattern was observed for most AESIs, rates also varied by provenance of disease diagnosis (primary care, specialist care). Thrombosis with thrombocytopenia rates were extremely low ranging from 0.06 to 4.53/100,000 person-years for cerebral venous sinus thrombosis (CVST) with thrombocytopenia (TP) and mixed venous and arterial thrombosis with TP, respectively. INTERPRETATION: Given the nature of the AESIs and the setting (general practitioners or hospital-based databases or both), background rates from databases that show the highest level of completeness (primary care and specialist care) should be preferred, others can be used for sensitivity. The study was designed to ensure representativeness to the European population and generalizability of the background incidence rates. FUNDING: The project has received support from the European Medicines Agency under the Framework service contract nr EMA/2018/28/PE.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Trombocitopenia , Humanos , Estudos de Coortes , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Atenção à Saúde , População Europeia
4.
Toxicon ; 184: 143-151, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32522618

RESUMO

Toxopneustes roseus is a species of sea urchin with a wide distribution along the eastern Pacific coast. It belongs to the Toxopneustidae family and, like its members, has well-developed globiferous pedicellariae that exert a variety of pharmacological actions. We identified six volatile non-peptide molecules from its globiferous pedicellariae by using GC-MS and RP-HPLC-MS/MS, including: benzoic acid; 2-aminoethanol (MEA); 2-(dimethylamine) ethanol (DMAE); 1- (4-bromophenyl)-1-phenylethanol (BPPE); 2-[1-(4-bromophenyl)-1- phenylethoxy]-N,N-dimethylethanamine (EMB); and 2-[1-(4-chlorphenyl)-1- phenylethoxy]-N,N-dimethylethanamine (CLX). The construction of a pharmacophore model and the in silico molecular docking of EMB and CLX into the human voltage-gated sodium channel hNaV1.7 allowed establishing that these molecules are structurally similar to local anesthetics and other NaV channel blockers and can bind to the same site receptor in NaV channels; suggesting that both molecules are active components in T. roseus venom. Furthermore, a viable endogenous biopathway is proposed in which T. roseus can synthesize EMB and CLX from benzoic acid, MEA, DMAE, and BPPE as their precursors, which would emphasize the importance of these molecules in the metabolism of this sea urchin.


Assuntos
Ouriços-do-Mar , Peçonhas , Sequência de Aminoácidos , Animais , Sítios de Ligação , Humanos , Simulação de Acoplamento Molecular , Espectrometria de Massas em Tandem
5.
Tree Physiol ; 40(4): 445-453, 2020 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-32031664

RESUMO

As radial root resistance (Rp) represents one of the key components of the soil-plant-atmosphere continuum resistance catena modulating water transport, understanding its control is essential for physiologists, modelers and breeders. Reports of Rp, however, are still scarce and scattered in the scientific literature. In this study, we assessed genetic variability in Rp and its dependence on temperature in five widely used olive cultivars. In a first experiment, cultivar differences in Rp at 25 °C were evaluated from flow-pressure measurements in excised roots and subsequent analysis of root traits. In a second experiment, similar determinations were performed continually over a 5-h period in which temperature was gradually increased from 12 to 32 °C, enabling the assessment of Rp response to changing temperature. Despite some variability, our results did not show statistical differences in Rp among cultivars in the first experiment. In the second, cultivar differences in Rp were not significant at 12 °C, but they became so as temperature increased. Furthermore, the changes in Rp between 12 and 32 °C were higher than those expected by the temperature-driven decrease in water viscosity, with the degree of that change differing among cultivars. Also, Rp at 25 °C reached momentarily in the second experiment was consistently higher than in the first at that same, but fixed, temperature. Overall, our results suggest that there is limited variability in Rp among the studied cultivars when plants have been exposed to a given temperature for sufficient time. Temperature-induced variation in Rp might thus be partly explained by changes in membrane permeability that occur slowly, which explains why our values at 25 °C differed between experiments. The observed cultivar differences in Rp with warming also indicate faster acclimation of Rp to temperature changes in some cultivars than others.


Assuntos
Olea/genética , Raízes de Plantas/genética , Solo , Temperatura , Água
6.
BMC Genomics ; 20(1): 131, 2019 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-30755158

RESUMO

BACKGROUND: Genetically engineered mice (GEM) are essential tools for understanding gene function and disease modeling. Historically, gene targeting was first done in embryonic stem cells (ESCs) derived from the 129 family of inbred strains, leading to a mixed background or congenic mice when crossed with C57BL/6 mice. Depending on the number of backcrosses and breeding strategies, genomic segments from 129-derived ESCs can be introgressed into the C57BL/6 genome, establishing a unique genetic makeup that needs characterization in order to obtain valid conclusions from experiments using GEM lines. Currently, SNP genotyping is used to detect the extent of 129-derived ESC genome introgression into C57BL/6 recipients; however, it fails to detect novel/rare variants. RESULTS: Here, we present a computational pipeline implemented in the Galaxy platform and in BASH/R script to determine genetic introgression of GEM using next generation sequencing data (NGS), such as whole genome sequencing (WGS), whole exome sequencing (WES) and RNA-Seq. The pipeline includes strategies to uncover variants linked to a targeted locus, genome-wide variant visualization, and the identification of potential modifier genes. Although these methods apply to congenic mice, they can also be used to describe variants fixed by genetic drift. As a proof of principle, we analyzed publicly available RNA-Seq data from five congenic knockout (KO) lines and our own RNA-Seq data from the Sall2 KO line. Additionally, we performed target validation using several genetics approaches. CONCLUSIONS: We revealed the impact of the 129-derived ESC genome introgression on gene expression, predicted potential modifier genes, and identified potential phenotypic interference in KO lines. Our results demonstrate that our new approach is an effective method to determine genetic introgression of GEM.


Assuntos
Animais Geneticamente Modificados/genética , Patrimônio Genético , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Animais , Biologia Computacional , Inibidor de Quinase Dependente de Ciclina p21/genética , Proteínas de Ligação a DNA , Células-Tronco Embrionárias/fisiologia , Regulação da Expressão Gênica , Genes Modificadores , Peptídeos e Proteínas de Sinalização Intracelular/genética , Camundongos , Camundongos da Linhagem 129 , Camundongos Congênicos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas/genética , Análise de Sequência de RNA , Fatores de Transcrição , Sequenciamento do Exoma
7.
Rev. chil. obstet. ginecol. (En línea) ; 82(2): 241-246, abr. 2017. ilus
Artigo em Espanhol | LILACS | ID: biblio-899899

RESUMO

Los tumores sincrónicos del tracto genital femenino son un entidad infrecuente que plantea un reto en el diagnóstico diferencial con la enfermedad metastásica. La mayoría de ellos son cánceres de endometrio y ovario, siendo los tumores sincrónicos de endometrio (CE) y trompa (CT) una asociación excepcional. Presentamos el caso de una paciente de 54 años con un diagnóstico preoperatorio de CE en la en la pieza quirúrgica se desveló la existencia de un tumor sincrónico de trompa izquierda. A propósito de este caso se realiza una revisión del tema haciendo hincapié en cómo llegar a un correcto diagnóstico de los tumores independientes descartando la extensión tumoral y la enfermedad metastásica.


Synchronous primary cancers of gynecological tract are uncommon and a challenge in the differential diagnosis with metastatic disease. Most of them are endometrial and ovarian cancers. Synchronous primary endometrial (EC) and tube fallopian cancers (TC) are a very rare association. We report the case of a patient of 54 years with EC preoperative diagnosis with synchronous left TC postoperative diagnosis. We review the topic emphasizing how to reach a correct diagnosis of tumors independent refusing the tumor invasion and metastatic disease.


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Neoplasias do Endométrio/patologia , Neoplasias das Tubas Uterinas/patologia , Neoplasias Primárias Múltiplas/cirurgia , Neoplasias do Endométrio/cirurgia , Diagnóstico Diferencial , Neoplasias das Tubas Uterinas/cirurgia , Neoplasias Primárias Múltiplas/patologia
8.
J Evol Biol ; 28(7): 1410-6, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26012357

RESUMO

Despite the long-standing interest in nonstationarity of both phenotypic evolution and diversification rates, only recently have methods been developed to study this property. Here, we propose a methodological expansion of the phylogenetic signal-representation (PSR) curve based on phylogenetic eigenvectors to test for nonstationarity. The PSR curve is built by plotting the coefficients of determination R(2) from phylogenetic eigenvector regression (PVR) models increasing the number of phylogenetic eigenvectors against the accumulated eigenvalues. The PSR curve is linear under a stationary model of trait evolution (i.e. the Brownian motion model). Here we describe the distribution of shifts in the models R(2) and used a randomization procedure to compare observed and simulated shifts along the PSR curve, which allowed detecting nonstationarity in trait evolution. As an applied example, we show that the main evolutionary pattern of variation in the theropod dinosaur skull was nonstationary, with a significant shift in evolutionary rates in derived oviraptorosaurs, an aberrant group of mostly toothless, crested, birdlike theropods. This result is also supported by a recently proposed Bayesian-based method (AUTEUR). A significant deviation between Ceratosaurus and Limusaurus terminal branches was also detected. We purport that our new approach is a valuable tool for evolutionary biologists, owing to its simplicity, flexibility and comprehensiveness.


Assuntos
Evolução Biológica , Filogenia , Crânio/anatomia & histologia , Animais , Teorema de Bayes , Dinossauros , Análise de Regressão
9.
Artigo em Inglês | MEDLINE | ID: mdl-25569929

RESUMO

The study of the mechanical and environmental factors that regulate a fundamental event such as fertilization have been subject of multiple studies. Nevertheless, the microscopical size of the spermatozoa and the high beating frequency of their flagella (up to 20 Hz) impose a series of technological challenges for the study of the mechanical factors implicated. Traditionally, due to the inherent characteristics of the rapid sperm movement, and to the technological limitations of microscopes (optical or confocal) to follow in three dimensions (3D) their movement, the analysis of their dynamics has been studied in two dimensions, when the head is confined to a surface. Flagella propel sperm and while their head can be confined to a surface, flagellar movement is not restricted to 2D, always displaying 3D components. In this work, we present a highly novel and useful tool to analyze sperm flagella dynamics in 3D. The basis of the method is a 100 Hz oscillating objective mounted on a bright field optical microscope covering a 16 microns depth space at a rate of ~ 5000 images per second. The best flagellum focused subregions were associated to their respective Z real 3D position. Unprecedented graphical results making evident the 3D movement of the flagella are shown in this work and supplemental material illustrating a 3D animation using the obtained experimental results is also included.


Assuntos
Imageamento Tridimensional/métodos , Motilidade dos Espermatozoides/fisiologia , Cauda do Espermatozoide/fisiologia , Humanos , Masculino , Movimento
10.
Bioresour Technol ; 135: 128-36, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23265815

RESUMO

The microalga Nannochloropsis sp. was used in this study, in a biorefinery context, as biomass feedstock for the production of fatty acids for biodiesel, biohydrogen and high added-value compounds. The microalgal biomass, which has a high lipid and pigment content (mainly carotenoids), was submitted to supercritical CO2 extraction. The temperature, pressure and solvent flow-rate were evaluated to check their effect on the extraction yield. The best operational conditions to extract 33 g lipids/100 g dry biomass were found to be at 40 °C, 300 bar and a CO2 flow-rate of 0.62 g/min. The effect of adding a co-solvent (ethanol) was also studied. When supercritical CO2 doped with 20% (w/w) ethanol was used, it was possible to extract 45 g lipids/100 g dry biomass of lipids and recover 70% of the pigments. Furthermore, the remaining biomass after extraction was effectively used as feedstock to produce biohydrogen through dark fermentation by Enterobacter aerogenes resulting in a hydrogen production yield of 60.6 mL/g dry biomass.


Assuntos
Biocombustíveis/microbiologia , Biomassa , Biotecnologia/métodos , Hidrogênio/metabolismo , Microalgas/metabolismo , Óleos/isolamento & purificação , Pigmentos Biológicos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Cromatografia com Fluido Supercrítico , Fermentação , Lipídeos/análise , Solventes/química
11.
Neurology ; 77(10): 996-9, 2011 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-21865579

RESUMO

OBJECTIVE: The clinical characteristics of patients with relapsing anti-NMDA receptor (NMDAR) encephalitis are not well-defined. In this study, we report the clinical profile and outcome of relapses in a series of anti-NMDAR encephalitis. METHODS: We did a retrospective review of relapses that occurred in 25 patients with anti-NMDAR encephalitis. Relapses were defined as any new psychiatric or neurologic syndrome, not explained by other causes, which improved after immunotherapy or, less frequently, spontaneously. RESULTS: A total of 13 relapses were identified in 6 patients. Four of them had several, 2 to 4, relapses. There was a median delay of 2 years (range 0.5 to 13 years) for the first relapse. Median relapse rate was 0.52 relapses/patient-year. Relapse risk was higher in patients who did not receive immunotherapy in the first episode (p = 0.009). Most cases (53%) presented partial syndromes of the typical anti-NMDAR encephalitis. Main symptoms of relapses were speech dysfunction (61%), psychiatric (54%), consciousness-attention disturbance (38%), and seizures (31%). Three relapses (23%) presented with isolated atypical symptoms suggestive of brainstem-cerebellar involvement. An ovarian teratoma was detected at relapse in only 1 patient (17%). Relapses did not add residual deficit to that caused by the first episode. CONCLUSIONS: Relapses in anti-NMDAR encephalitis are common (24%). They may occur many years after the initial episode. Relapses may present with partial aspects or with isolated symptoms of the full-blown syndrome. Immunotherapy at first episode reduces the risk of relapses.


Assuntos
Autoanticorpos/biossíntese , Encefalite/imunologia , Receptores de N-Metil-D-Aspartato/imunologia , Adolescente , Adulto , Autoanticorpos/sangue , Criança , Pré-Escolar , Encefalite/diagnóstico , Feminino , Seguimentos , Células HEK293 , Humanos , Imunoterapia/métodos , Lactente , Masculino , Pessoa de Meia-Idade , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Receptores de N-Metil-D-Aspartato/sangue , Recidiva , Estudos Retrospectivos , Adulto Jovem
12.
Mar Pollut Bull ; 60(4): 526-35, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20005532

RESUMO

Identifying petroleum-related products released into the environment is a complex and difficult task. To achieve this, polycyclic aromatic hydrocarbons (PAHs) are of outstanding importance nowadays. Despite traditional quantitative fingerprinting uses straightforward univariate statistical analyses to differentiate among oils and to assess their sources, a multivariate strategy based on Procrustes rotation (PR) was applied in this paper. The aim of PR is to select a reduced subset of PAHs still capable of performing a satisfactory identification of petroleum-related hydrocarbons. PR selected two subsets of three (C(2)-naphthalene, C(2)-dibenzothiophene and C(2)-phenanthrene) and five (C(1)-decahidronaphthalene, naphthalene, C(2)-phenanthrene, C(3)-phenanthrene and C(2)-fluoranthene) PAHs for each of the two datasets studied here. The classification abilities of each subset of PAHs were tested using principal components analysis, hierarchical cluster analysis and Kohonen neural networks and it was demonstrated that they unraveled the same patterns as the overall set of PAHs.


Assuntos
Petróleo/análise , Hidrocarbonetos Policíclicos Aromáticos/química , Análise por Conglomerados , Redes Neurais de Computação , Análise de Componente Principal
13.
Water Res ; 43(4): 1015-26, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19091372

RESUMO

This paper compares the weathering patterns of two similar fuel oils: a fuel oil spilled after a ship accident (Prestige-Nassau, off the Galician coast -NW Spain-) and a fuel designed to cope with the numerous quests for samples to carry out scientific studies (IFO). Comparative studies were made to evaluate the capability of common fingerprinting analytical techniques to differentiate the fuels, as well as their capabilities to monitor their weathering. The two products were spilled under controlled conditions during ca. four months to assess how they evolved on time. Mid-IR spectrometry and gas chromatography (flame ionization and mass spectrometry detectors) were used. IR indexes related to total aromaticity, type of substituents (branched or linear chains) and degree of aromatic substitution reflected well the differences between the fuels during weathering. Regarding the chromatographic measurements, the n-alkanes became highly reduced for both fuel oils and it was found that the PAHs of the synthetic fuel (IFO) were more resistant to weathering. Regarding biomarkers, the different profiles of the steranes, diasteranes and triaromatic steroids allowed for a simple differentiation amongst the two products. The %D2/P2 ratio differentiated both products whereas the %N3/P2 one ordered the samples according to the extent of their weathering.


Assuntos
Óleos Combustíveis/análise , Estabilidade de Medicamentos , Ionização de Chama , Cromatografia Gasosa-Espectrometria de Massas , Raios Infravermelhos , Espectrometria de Massas , Água do Mar , Espectroscopia de Infravermelho com Transformada de Fourier , Sulfóxidos/análise , Tempo (Meteorologia)
14.
Mar Pollut Bull ; 56(2): 335-47, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18054966

RESUMO

A set of 34 worldwide crude oils, 12 distilled products (kerosene, gas oils, and fuel oils) and 45 oil samples taken from several Galician beaches (NW Spain) after the wreckage of the Prestige tanker off the Galician coast was studied. Gas chromatography with flame ionization detection was combined with chemometric multivariate pattern recognition methods (principal components analysis, cluster analysis and Kohonen neural networks) to differentiate and characterize the Prestige fuel oil. All multivariate studies differentiated between several groups of crude oils, fuel oils, distilled products, and samples belonging to the Prestige's wreck and samples from other illegal discharges. In addition, a reduced set of 13 n-alkanes out of 36, were statistically selected by Procrustes Rotation to cope with the main patterns in the datasets. These variables retained the most important characteristics of the data set and lead to a fast and cheap analytical screening methodology.


Assuntos
Monitoramento Ambiental/métodos , Reconhecimento Automatizado de Padrão/métodos , Petróleo/análise , Poluentes Químicos da Água/análise , Praias , Cromatografia Gasosa/métodos , Ionização de Chama/métodos , Navios , Estatística como Assunto
15.
Talanta ; 74(2): 163-75, 2007 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-18371626

RESUMO

A fast analytical tool based on attenuated total reflectance mid-IR spectrometry is presented to evaluate the origin of spilled hydrocarbons and to monitor their fate on the environment. Ten spectral band ratios are employed in univariate and multivariate studies (principal components analysis, cluster analysis, density functions - potential curves - and Kohonen self organizing maps). Two indexes monitor typical photooxidation processes, five are related to aromatic characteristics and three study aliphatic and branched chains. The case study considered here comprises 45 samples taken on beaches (from 2002 to 2005) after the Prestige carrier accident off the Galician coast and 104 samples corresponding to weathering studies deployed for the Prestige's fuel, four typical crude oils and a fuel oil. The univariate studies yield insightful views on the gross chemical evolution whereas the multivariate studies allow for simple and straightforward elucidations on whether the unknown samples match the Prestige's fuel. Besides, a good differentiation on the weathering patterns of light and heavy products is obtained.


Assuntos
Monitoramento Ambiental/métodos , Petróleo/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental/instrumentação , Recuperação e Remediação Ambiental , Espanha , Tempo (Meteorologia)
16.
Rev. chil. obstet. ginecol ; 72(4): 210-216, 2007. tab
Artigo em Espanhol | LILACS | ID: lil-477386

RESUMO

Antecedentes: La vitamina A, principalmente en su forma de ácido todo trans-retinoico, desempeña una función de vital importancia durante el desarrollo gestacional en todos los tejidos y órganos del cuerpo. Objetivo: Determinar los niveles de ácido retinoico en el suero de sangre de cordón umbilical y relacionarlos con el peso/edad gestacional del recién nacido y el consumo materno de vitamina A, conjuntamente con variables socio-económicas y nutricionales. Método: Estudio descriptivo de corte transversal, analizando un total de 62 neonatos y sus madres, provenientes de las maternidades de los Hospitales San José y Barros Luco-Trudeau, Santiago de Chile. Resultados: En la población en estudio se observó una relación directa entre el peso/edad gestacional del neonato y el consumo materno de vitamina A, pero no con los niveles de esa vitamina en el suero de sangre de cordón umbilical. Se encontró que el consumo medio de vitamina A en las embarazadas fue sólo de 2298 +/- 1416,8 Ul, siendo la dosis recomendada por OMS de 8000 Ul. Conclusión: Existe asociación entre la ingesta de vitamina A y el estado nutricional materno en relación con el peso/edad gestacional del neonato. Debido a que los requerimientos nutricionales del feto están privilegiados por sobre los maternos, no se observaron diferencias en las características antropométricas del neonato asociadas a la ingesta materna de vitamina A.


Background: Vitamin A, mainly in their form of retinoic acid, it carries out a function of vital importance during the gestational development, in all the tissues and organs of the body. Objective: To evaluate the levels of retinoic acid in the serum of blood from umbilical cord and to relate them with the weight/gestational age ratio of the newborns and the maternal intake of vitamin A, jointly with socioeconomic and nutritional variables. Method: A descriptive study of traverse court, in the maternities of the Hospitals San José and Barros Luco-Trudeau of Santiago, Chile, studying a total of 62 cases. Results: In the population in study a direct relationship was observed between the newborn ratio weight/gestational age and the maternal consumption of vitamin A, but no relationship was found among the same weight/gestational age ratio and the levels of this vitamin in the serum of blood of umbilical cord. On the other hand, it was found that the average consumption of vitamin A in the maternities it was of 2298 +/- 1416.8 IU, being the dose recommended by WHO for pregnant of 8000 IU, therefore, the whole population in study had a faulty consumption of vitamin A. Conclusion: Exists association among the intake of vitamin A and the maternal nutritional state with the weight/gestational age ratio of the newborn and the concentration of trans-retinoic acid in the umbilical cord. Because the nutritional requirements of the fetus are privileged over the maternal ones, differences were not observed in the newborn anthropometries features associated to the maternal vitamin A intake.


Assuntos
Humanos , Feminino , Recém-Nascido , Adulto , Desenvolvimento Fetal/fisiologia , Sangue Fetal , Fenômenos Fisiológicos da Nutrição Materna/fisiologia , Fenômenos Fisiológicos da Nutrição Pré-Natal/fisiologia , Tretinoína/sangue , Análise de Variância , Antropometria , Peso ao Nascer , Estudos Transversais , Epidemiologia Descritiva , Idade Gestacional , Estado Nutricional , Fatores Socioeconômicos , Vitamina A/fisiologia
17.
Cienc. Trab ; 6(14): 197-201, oct.-dic. 2004.
Artigo em Espanhol | LILACS | ID: lil-420807

RESUMO

Los factores psicosociales han cobrado especial importancia por cuanto los estudios acerca del estrés y sus secuelas han mostrado el crecimiento de afecciones de salud en la población y con mayor énfasis en la trabajadora, en la que la exposición a condiciones de laborales deteriorantes alcanza cifras que pueden catalogarse como un problema emergente de la salud pública. La atención y la prevención de los efectos adversos del estrés ocupacional suponen su comprensión y su abordaje bajo un modelo sistémico, que permita dar cuenta tanto de la red de factores causales como de los impactos tanto en el nivel subjetivo como colectivo. La Vigilancia Epidemiológica de los factores psicosociales se vislumbra como una alternativa que permite de forma sistemática tomar información de las características de la organización, de la tarea del grupo social y de las condiciones de salud de los trabajadores, a fin de realizar acciones de intervención, que con adecuado seguimiento permitan mostrar su impacto y den soporte a los procesos de atención y al mismo tiempo de investigación en las cohortes ocupacionales.


Assuntos
Adulto , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Saúde Mental , Doenças Profissionais , Qualidade de Vida , Estresse Fisiológico , Trabalho/psicologia , América Latina
18.
Am J Orthod Dentofacial Orthop ; 118(4): 366-70, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11029729

RESUMO

The purpose of this investigation was to determine and quantify vertical changes in the position of the mandibular molars while maintaining arch perimeter with a fixed lingual arch. Twenty-three patients with a mean age of 10.4 +/- 0.6 years were selected to receive fixed lingual arch treatment as the only appliance in the mandibular arch. Average treatment time was 18.3 +/-+/- 0.6 months. Longitudinal records for 12 and 24 months of 24 individuals matched by ethnic origin, age, gender, and mandibular plane inclination were used as controls. Pretreatment and posttreatment cephalograms were used to determine positional changes. Statistically significant differences between the fixed lingual arch and control groups were found. The results of this investigation indicated that the mandibular fixed lingual arch is a useful tool to control the vertical development of the mandibular molars.


Assuntos
Mandíbula/anatomia & histologia , Aparelhos Ortodônticos Funcionais , Técnicas de Movimentação Dentária/instrumentação , Cefalometria , Criança , Arco Dental/anatomia & histologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Dente Molar/crescimento & desenvolvimento , Dente Molar/fisiologia , Resultado do Tratamento
19.
Rev Biol Trop ; 48(2-3): 587-9, 2000.
Artigo em Espanhol | MEDLINE | ID: mdl-11354965

RESUMO

We examined if seed abortion in Guanacaste free fruits (Enterolobium cyclocarpum) is related to position within fruits, by establishing the abortion ratio in 150 fruits from 10 trees, collected in Santa Rosa National Park (Guanacaste, Costa Rica). Fruits were divided in basal, central and distal sections. We found marginal differences in abortion ratio between these sections (Anova, p = 0.058), and also among trees (p = 0.01). In general, the distal section had the greatest abortion ratio in relation to other sections. This abortion pattern could be caused by resource competition within siblings and not by genetic differences among them.


Assuntos
Frutas/fisiologia , Sementes/fisiologia , Árvores/fisiologia , Frutas/anatomia & histologia , Reprodução
20.
Tree Physiol ; 20(1): 65-72, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12651528

RESUMO

Radiation-use efficiency (RUE) relates biomass production to the photosynthetically active radiation (PAR) intercepted by a plant or crop. We determined RUE and biomass partitioning coefficients of young olive (Olea europaea) trees for use in a general growth model. In 1995, 1-year-old olive trees var. 'Picual' were planted at a density of either 0.5 or 2.0 trees m(-2) near Córdoba, Spain, at a site providing favorable growth conditions. During the experiment (1995-1997), both PAR interception by the canopy and plant area index (PAI) were measured with radiation sensors. Regular harvests were performed to determine leaf area and biomass accumulation in roots, wood (stem, branches and trunk) and leaves. Leaf, wood and root biomass partitioning coefficients were calculated. The leaf area partitioning coefficients were also estimated. Dry matter production was linearly related to cumulative intercepted PAR. Seasonal RUE, calculated as the slope of the regression of aboveground biomass and cumulative intercepted PAR, was 1.35 g (MJ PAR)(-1). Radiation-use efficiency appeared to respond to environmental conditions, but was independent of planting density and PAI. The young olive trees allocated 0.26 of their total biomass to roots. Partitioning of aboveground dry matter was 0.60 to wood and 0.37 to leaves. As competition increased, dry matter partitioning to wood increased to 0.70.

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