227 research outputs found
Portuguese Adaptation of Students Engagement in Schools International Scale (SESIS)
The importance of student’s engagement has been recently pointed out in research. However, there has been a lack of engagement assessment instrument, pertaining psychometric qualities. Objective: This paper presents the Portuguese adaptation of the “Student’s Engagement in School International Scale” (SESIS), drawn up from a12 countries international study (Lam et al., 2012; Lam et al., in press). Method: Psychometric properties of this scale were examined with data from 685 students from different grades (6th, 7th, 9th and 10th), from both sexes, and different regions of the country. Results: Factorial analysis of the results, with varimax rotation, lead to three different factors which explain 50.88% of the variance. The scale integrates the original 33 items, and cognitive, affective and behavioural dimensions. For the external validity study, the relationship between student’s engagement in school results and other school variables — academic performance, self-concept — was considered, and significant relations were observed, as expected. Conclusion: The data presented highlights the qualities of SESIS, as well as its usefulness for research purposes. Suggestion: It is suggested the investigation of the extension of SESIS’s three-dimensionality, in future studiesKeywords: Innovation, technology, research projects, etc. [Arial 10-point, justified alignment]
XRD Identification of Ore Minerals during Cruises: Refinement of Extraction Procedure with Sodium Acetate Buffer
The on-board identification of ore minerals during a cruise is often postponed until long after the cruise is over. During the M127 cruise, 21 cores with deep-seafloor sediments were recovered in the Trans-Atlantic Geotraverse (TAG) field along the Mid Atlantic Ridge (MAR). Sediments were analyzed on-board for physicochemical properties such as lightness (L*), pH and Eh. Selected samples were studied for mineral composition by X-ray powder diffraction (XRD). Based on XRD data, sediment samples were separated into high-, low- and non-carbonated. Removal of carbonates is a common technique in mineralogical studies in which HCl is used as the extraction agent. In the present study, sequential extraction was performed with sodium acetate buffer (pH 5.0) to remove carbonates. The ratio between the highest calcite XRD reflection in the original samples (Iorig) vs its XRD-reflection in samples after their treatment with the buffer (Itreat) was used as a quantitative parameter of calcite removal, as well as to identify minor minerals in carbonated samples (when Iorig/Itreat > 24). It was found that the lightness parameter (L*) showed a positive correlation with calcite XRD reflection in selected TAG samples, and this could be applied to the preliminary on-board determination of extraction steps with acetate buffer (pH 5.0) in carbonated sediment samples. The most abundant minerals detected in carbonated samples were quartz and Al- and Fe-rich clays. Other silicates were also detected (e.g., calcic plagioclase, montmorillonite, nontronite). In non-carbonated samples, Fe oxides and hydroxides (goethite and hematite, respectively) were detected. Pyrite was the dominant hydrothermal mineral and Cu sulfides (chalcopyrite, covellite) and hydrothermal Mn oxides (birnessite and todorokite) were mineral phases identified in few samples, whereas paratacamite was detected in the top 20 cm of the core. The present study demonstrates that portable XRD analysis makes it possible to characterize mineralogy at cored sites, in particular in both low- and high-carbonated samples, before the end of most cruises, thus enabling the quick modification of exploration strategies in light of new information as it becomes available in near-real time
Type 1 Tyrosinaemia: Past and Present in a Metabolic Disease Unit
Introdução: A ti rosinemia ti po I é uma doença hereditária do metabolismo por défi ce de fumarilacetoacetase, com uma pre-
valência ao nascimento de 1:100000 e potencialmente fatal. O plano alimentar individualizado, o transplante hepato-renal e a
niti sinona são algumas das estratégias terapêuti cas.
Métodos: Estudo retrospeti vo, observacional e descriti vo de oito doentes acompanhados numa unidade de doenças meta-
bólicas, entre janeiro de 1981 e dezembro de 2012. Analisaram-se dados demográfi cos, manifestações clínicas, terapêuti ca,
evolução clínica e laboratorial.
Resultados: Na década de 80 do século passado foram diagnosti cados quatro doentes, dos quais dois faleceram em contexto
de insufi ciência hepáti ca e carcinoma hepatocelular, uma doente foi submeti da a transplante hepáti co e outra a transplante
hepato-renal. Ambas estão clinicamente bem, mantendo terapêuti ca imunossupressora. Na década seguinte foram diagnos-
ti cados dois doentes, dos quais um faleceu aos 3 meses por insufi ciência hepáti ca aguda e carcinoma hepatocelular. A outra
doente iniciou terapêuti ca com niti sinona e plano alimentar personalizado, com boa evolução clínica e laboratorial até à ado-
lescência, altura em que surgiram difi culdades escolares e de controlo metabólico, possivelmente relacionadas com períodos
de incumprimento dietéti co. O rastreio metabólico neonatal alargado permiti u diagnosti car dois doentes às 3 semanas de vida
em fase pré-sintomáti ca. Estes iniciaram plano alimentar personalizado e niti sinona e mantêm bom controlo metabólico e
desenvolvimento psicomotor adequado.
Discussão: A possibilidade de diagnósti co precoce e uti lização da niti sinona revolucionaram o prognósti co dos doentes com
ti rosinemia ti po 1. O risco de carcinoma hepatocelular e outras complicações implicam vigilância clínica, laboratorial e imagio-
lógica regular.info:eu-repo/semantics/publishedVersio
Pyruvate Dehydrogenase Complex Deficiency: Updating the Clinical, Metabolic and Mutational Landscapes in a Cohort of Portuguese Patients
Background: The pyruvate dehydrogenase complex (PDC) catalyzes the irreversible decarboxylation of pyruvate into acetyl-CoA. PDC deficiency can be caused by alterations in any of the genes encoding its several subunits. The resulting phenotype, though very heterogeneous, mainly affects the central nervous system. The aim of this study is to describe and discuss the clinical, biochemical and genotypic information from thirteen PDC deficient patients, thus seeking to establish possible genotype-phenotype correlations.
Results: The mutational spectrum showed that seven patients carry mutations in the PDHA1 gene encoding the E1α subunit, five patients carry mutations in the PDHX gene encoding the E3 binding protein, and the remaining patient carries mutations in the DLD gene encoding the E3 subunit. These data corroborate earlier reports describing PDHA1 mutations as the predominant cause of PDC deficiency but also reveal a notable prevalence of PDHX mutations among Portuguese patients, most of them carrying what seems to be a private mutation (p.R284X). The biochemical analyses revealed high lactate and pyruvate plasma levels whereas the lactate/pyruvate ratio was below 16; enzymatic activities, when compared to control values, indicated to be independent from the genotype and ranged from 8.5% to 30%, the latter being considered a cut-off value for primary PDC deficiency. Concerning the clinical features, all patients displayed psychomotor retardation/developmental delay, the severity of which seems to correlate with the type and localization of the mutation carried by the patient. The therapeutic options essentially include the administration of a ketogenic diet and supplementation with thiamine, although arginine aspartate intake revealed to be beneficial in some patients. Moreover, in silico analysis of the missense mutations present in this PDC deficient population allowed to envisage the molecular mechanism underlying these pathogenic variants.
Conclusion: The identification of the disease-causing mutations, together with the functional and structural characterization of the mutant protein variants, allow to obtain an insight on the severity of the clinical phenotype and the selection of the most appropriate therapy.info:eu-repo/semantics/publishedVersio
Phenotype and Genotype of Portuguese Patients with Smith-Lemli-Opitz Syndrome
A síndrome de Smith-Lemli-Opitz (SLOS) é uma síndrome polimalformativa de transmissão autossómica recessiva causada
por um défice metabólico da biossíntese do colesterol, que se caracteriza por dismorfias craniofaciais, anomalias congénitas de vários órgãos (salientando-se as do esqueleto e do aparelho
urogenital), restrição de crescimento intra-uterino (RCIU), alterações
comportamentais e atraso mental. É causada por mutações no gene DHCR7, que codifica para a enzima 7-dehidrocolesterol
reductase, responsável pelo último passo da via metabólica da síntese do colesterol. A SLOS caracteriza-se por níveis diminuídos de colesterol e concentrações altas do seu precursor, 7-dehidrocolesterol, no sangue e tecidos.
Procedeu-se a uma análise comparativa dos fenótipo e genótipo de quinze casos de SLOS de origem portuguesa, e são tecidas considerações quanto às dificuldades e limitações inerentes ao diagnóstico,
e ao facto de esta doença hereditária do metabolismo dever ser considerada no diagnóstico diferencial das situações de (i) hipocolesterolémia, (ii) RCIU e (iii) síndromes polimalformativas,(especialmente
quando crianças com atraso de crescimento apresentam simultaneamente sindactilia do segundo e terceiro dedos do pé e
microcefalia e/ou narinas antevertidas entre outras anomalias)
Assessment of Cytotoxic Activity of Rosemary ( Rosmarinus officinalis
The objective of this study was to evaluate the cytotoxic activity of rosemary (REO, Rosmarinus officinalis L.), turmeric (CEO, Curcuma longa L.), and ginger (GEO, Zingiber officinale R.) essential oils in HeLa cells. Cytotoxicity tests were performed in vitro, using tetrazolium (MTT) and neutral red assays for evaluation of antiproliferative activity by different mechanisms, trypan blue assay to assess cell viability and evaluation of cell morphology for Giemsa to observe the cell damage, and Annexin V to evaluate cell death by apoptosis. CEO and GEO exhibited potent cytotoxic activity against HeLa cells. IC50 obtained was 36.6 μg/mL for CEO and 129.9 μg/mL for GEO. The morphology of HeLa cells showed condensation of chromatin, loss of cell membrane integrity with protrusions (blebs), and cell content leakage for cells treated with CEO and GEO, from the lowest concentrations studied, 32.81 μg/mL of CEO and 32.12 μg/mL of GEO. The Annexin V assay revealed a profile of cell death by apoptosis for both CEO and GEO. The results indicate cytotoxic activity in vitro for CEO and GEO, suggesting potential use as anticancer agents for cervical cancer cells
Congenital Disorders of Glycosylation in Portugal—Two Decades of Experience
Objective: To describe the clinical, biochemical, and genetic features of both new and previously reported patients with congenital disorders of glycosylation (CDGs) diagnosed in Portugal over the last 20 years.
Study design: The cohort includes patients with an unexplained multisystem or single organ involvement, with or without psychomotor disability. Serum sialotransferrin isoforms and, whenever necessary, apolipoprotein CIII isoforms and glycan structures were analyzed. Additional studies included measurement of phosphomannomutase (PMM) activity and analysis of lipid-linked oligosaccharides in fibroblasts. Sanger sequencing and massive parallel sequencing were used to identify causal variants or the affected gene, respectively.
Results: Sixty-three individuals were diagnosed covering 14 distinct CDGs; 43 patients diagnosed postnatally revealed a type 1, 14 a type 2, and 2 a normal pattern on serum transferrin isoelectrofocusing. The latter patients were identified by whole exome sequencing. Nine of them presented also a hypoglycosylation pattern on apolipoprotein CIII isoelectrofocusing, pointing to an associated O-glycosylation defect. Most of the patients (62%) are PMM2-CDG and the remaining carry pathogenic variants in ALG1, ATP6AP1, ATP6AP2, ATP6V0A2, CCDC115, COG1, COG4, DPAGT1, MAN1B1, SLC35A2, SRD5A3, RFT1, or PGM1.
Conclusions: Portuguese patients with CDGs are presented in this report, some of them showing unique clinical phenotypes. Among the 14 genes mutated in Portuguese individuals, 8 are shared with a previously reported Spanish cohort. However, regarding the mutational spectrum of PMM2-CDG, the most frequent CDG, a striking similarity between the 2 populations was found, as only 1 mutated allele found in the Portuguese group has not been reported in Spain.info:eu-repo/semantics/publishedVersio
Isotopic investigation in the region of Pax Julia during paleochristian occupation: paleodiets and mobility
In this study, diet and mobility of the Palaeochristian populations from the Roman
villae of São Cucufate and Cegonha, and from
the necropolis of Alpendre dos Lagares, located
in the Beja region in southern Portugal, was
investigated by isotopic analysis.
Osteological tissues provide information on diet and mobility of the individuals.
Isotopic analysis of delta 13C and delta 15N of bones can be used to determine the food intake of ancient populations whose dietary habits are not well known due to the lack of archaeological evidence. Isotopic ratios of the bone organic (delta 13C and delta 15N) and inorganic fractions (delta 13C) can provide information on the types of plants
ingested , the amount of animal resources,
terrestrial versus marine resources, as well as breastfeeding and weaning practices.
Individual mobility can be assessed by the
measurement of 87Sr/86Sr in the inorganic fraction of teeth and bones. The local 87Sr/86Sr geological ignature where the individual spent its childhood is recorded in the teeth, while 87Sr/86Sr recorded in bones relates to the place where the individual spent the last 10 years before death. Comparison of the Sr isotopic signature of teeth and bones can be used to infer about the individual’s mobility pattern.
Bone isotopic analysis can be compromised by
the diagenetic processes which occur during
burial. In this study, FTIR (Fourier Transformed Infrared Spectroscopy) and XRD (X-Ray Diffraction) analyses were used to assess the diagenetic processes impacting the skeletons. Dietary isotopic analysis of studied populations indicates a mixed terrestrial diet, with some small inter- and intra-populational variations. Dietary isotopic values obtained for the Paleochristian population of Pax Julia are roughly similar to Roman populations in the Mediterranean area. In terms of mobility, analysis of the Cegonha individuals proved they were mainly local with some evidence of limited movements
Energy dependence of Cronin momentum in saturation model for and collisions
We calculate dependence of Cronin momentum for and
collisions in saturation model. We show that this dependence is consistent with
expectation from formula which was obtained using simple dimentional
consideration. This can be used to test validity of saturation model (and
distinguish among its variants) and measure dependence of saturation
momentum from experimental data.Comment: LaTeX2e, 12 pages, 8 figure
The natural history of classic galactosemia: lessons from the GalNet registry.
BACKGROUND
Classic galactosemia is a rare inborn error of carbohydrate metabolism, caused by a severe deficiency of the enzyme galactose-1-phosphate uridylyltransferase (GALT). A galactose-restricted diet has proven to be very effective to treat the neonatal life-threatening manifestations and has been the cornerstone of treatment for this severe disease. However, burdensome complications occur despite a lifelong diet. For rare diseases, a patient disease specific registry is fundamental to monitor the lifespan pathology and to evaluate the safety and efficacy of potential therapies. In 2014, the international Galactosemias Network (GalNet) developed a web-based patient registry for this disease, the GalNet Registry. The aim was to delineate the natural history of classic galactosemia based on a large dataset of patients.
METHODS
Observational data derived from 15 countries and 32 centers including 509 patients were acquired between December 2014 and July 2018.
RESULTS
Most affected patients experienced neonatal manifestations (79.8%) and despite following a diet developed brain impairments (85.0%), primary ovarian insufficiency (79.7%) and a diminished bone mineral density (26.5%). Newborn screening, age at onset of dietary treatment, strictness of the galactose-restricted diet, p.Gln188Arg mutation and GALT enzyme activity influenced the clinical picture. Detection by newborn screening and commencement of diet in the first week of life were associated with a more favorable outcome. A homozygous p.Gln188Arg mutation, GALT enzyme activity of ≤ 1% and strict galactose restriction were associated with a less favorable outcome.
CONCLUSION
This study describes the natural history of classic galactosemia based on the hitherto largest data set
- …