96 research outputs found
Épocas de floração de cultivares de oliveira em Castelo Branco, Elvas e Santarém
Comunicação apresentada no III Simpósio Nacional de Olivicultura que decorreu em Castelo Branco, de 29 a 31 de Outubro, na Escola Superior Agrária do Instituto Politécnico de Castelo Branco.A época de floração da oliveira está determinada pelas características genéticas
inerentes a cada cultivar e é influenciada por factores climatéricos, variáveis de ano para
ano. Esta influência do clima pode provocar importantes modificações anuais nas
épocas de floração, aspecto fundamental para a calendarização das técnicas culturais do
olival. Para além desta influência, a caracterização das épocas de floração é, também,
importante para o estudo e conhecimento da adaptação de diferentes cultivares a uma
região e para os programas de melhoramento genético, entre outros. Neste trabalho
caracteriza-se a época de floração de cinco cultivares de oliveira, nas regiões de Castelo
Branco, Elvas e Santarém, durante os anos de 2000, 2001 e 2002. Os resultados obtidos
revelaram a existência de diferenças nas datas de floração e na duração de floração,
entre cultivares e regiões, mantendo-se constante a ordem de entrada das cultivares em
floração. As condições climatéricas prevalecentes no período de Janeiro a Maio,
nomeadamente as temperaturas, condicionaram o calendário da floração, exercendo
uma marcada influência no momento de início da floração e na duração do período de
floração
Classic Bioelectrical Impedance Vector Reference Values for Assessing Body Composition in Male and Female Athletes
Bioimpedance standards are well established for the normal healthy population and in clinical settings, but they are not available for many sports categories. The aim of this study was to develop reference values for male and female athletes using classic bioimpedance vector analysis (BIVA). In this study, 1556 athletes engaged in different sports were evaluated during their off-season period. A tetrapolar bioelectrical impedance analyzer was used to determine measurements of resistance (R) and reactance (Xc). The classic BIVA procedure, which corrects bioelectrical values for body height, was applied, and fat-free mass, fat mass, and total body water were estimated. In order to verify the need for specific references, classic bioelectrical values were compared to the reference values for the general male and female populations. Additionally, athletes were divided into three groups: endurance, velocity/power, and team sports. In comparison with the general healthy male and female populations, the mean vectors of the athletes showed a shift to the left on the R-Xc graph. Considering the same set of modalities, BIVA confidence graphs showed that male and female endurance athletes presented lower body fluids, fat mass, and fat-free mass than other sets of modalities. This study provides BIVA reference values for an athletic population that can be used as a standard for assessing body composition in male and female athletes
The predictive role of raw bioelectrical impedance parameters in water compartments and fluid distribution assessed by dilution techniques in athletes
The aims of this study were to analyze the usefulness of raw bioelectrical impedance (BI) parameters in assessing water compartments and fluid distribution in athletes. A total of 202 men and 71 female athletes were analyzed. Total body water (TBW) and extracellular water (ECW) were determined by dilution techniques, while intracellular water (ICW) was calculated. Fluid distribution was calculated as the ECW/ICW ratio (E:I). Phase angle (PhA), resistance (R) and reactance (Xc) were obtained through BI spectroscopy using frequency 50kHz. Fat (FM) and fat\u2010free mass (FFM) were assessed by dual\u2010energy X\u2010ray absorptiometry. After adjusting for height, FM, FFM, age and sports category we observed that: PhA predicted ICW (females: \u3b2 = 1.62, p < 0.01; males: \u3b2 = 2.70, p < 0.01) and E:I (males and females: \u3b2 = 120.08; p < 0.01); R explained TBW (females: \u3b2 = 120.03; p < 0.01; males: \u3b2 = 120.06; p < 0.01) and ECW (females: \u3b2 = \u20130.02, p < 0.01; males: \u3b2 = 120.03, p < 0.01) and ICW (females: \u3b2 = \u20130.01, p < 0.053; males: \u3b2 = \u20130.03 p < 0.01); and Xc predicted ECW (females: \u3b2 = 120.06, p < 0.01; males: \u3b2 = 120.12, p < 0.01). A higher PhA is a good predictor of a larger ICW pool and a lower E:I, regardless of body composition, age, height, and sports category. Lower R is associated with higher water pools whereas ECW expansion is explained by lower Xc. Raw BI parameters are useful predictors of total and extracellular pools, cellular hydration and fluid distribution in athletes
Preliminary results on the growth and survival of the polychaete Nereis diversicolor (O. F. Müller, 1776), when fed with faeces from the carpet shell clam Ruditapes decussatus (L., 1758)
The growth and survival of the polychaete Nereis diversicolor (O. F. Müller, 1776) fed on faeces of the carpet shell clam Ruditapes decussatus (L., 1758) were studied under controlled temperature and salinity conditions. Juvenile worms were fed with clam R. decussatus faeces in the presence or absence of sediment during 65 days. Starvation treatments were tested as a control. The results of the present study show that the worms were able to grow using the clam faeces in the presence or absence of sediment. However, the worms from the trials with sediment showed a higher survival rate and biomass production than those from the trials in which no sediment was used. These findings suggest that a suspension of bivalve faeces can be used in the rearing of juvenile N. diversicolor in an integrated polyculture system.El crecimiento y la supervivencia del poliqueto Nereis diversicolor (O. F. Müller, 1776) alimentado con heces de almeja Ruditapes decussatus (L., 1758) fueron estimados bajo condiciones controladas de temperatura y salinidad. Los poliquetos juveniles fueron alimentados con heces en presencia y ausencia de sedimento durante 65 días. Como control se aplicaron tratamientos de ayuno. Los resultados sugieren que los poliquetos crecieron usando las heces como única dieta en presencia y en ausencia de sedimento. Es más: los poliquetos de los ensayos con sedimiento mostraron supervivencia y producción de biomasa mayores que aquéllos en que no se utilizó sedimiento. Los resultados sugieren que se puede usar una suspensión de heces procedentes de bivalvos en el cultivo de juveniles de N. diversicolor en un sistema de policultivo integrado.Instituto Español de Oceanografí
Validação da bioimpedância elétrica por multifrequência em atletas
É reconhecida a importância de avaliar a composição corporal na população atlética. Para o
efeito é preciso utilizar técnicas válidas na determinação dos principais componentes moleculares. A
Densitometria Radiológica de Dupla Energia (DXA) é um método preciso e válido para avaliação de
composição corporal. No entanto, a DXA é uma técnica ainda pouco acessível em contextos não
laboratoriais. Desta forma, é importante utilizar técnicas mais simples e práticas como a bioimpedância
eléctrica (BIA). No entanto poucos estudos validaram a BIA especialmente de multifrequência na
avaliação da composição corporal em atletas. Assim, o objetivo desta investigação é testar a validade da
BIA de multifrequência (Tanita, modelo MC-180) na determinação do conteúdo mineral ósseo (CMO),
massa gorda (MG) e massa isenta de gordura e osso (MIGO) em atletas. Um total de 79 atletas (35
homens) foram avaliados pela BIA e pela DXA. Comparação de médias, coeficiente de correlação de
concordância, regressão múltipla, e o método Bland-Altman foram realizados. A Tanita apresentou um
poder explicativo de 76 %, 72%, 95% e 73% da variabilidade total observada a partir do método de
referência para a MG (kg), MG (%), MIGO e CMO, respectivamente. O coeficiente de correlação de
concordância para a MIGO apresentou uma força de concordância substancial de 0.927. Observaram-se
limites de concordância relativamente elevados na estimativa dos vários componentes corporais. Em
conclusão, a Tanita MC-180 é uma alternativa válida especialmente na estimação da massa isenta de
gordura e de osso, num grupo de atletas. Contudo, devido aos limites de concordância obtidos na
determinação das vários componentes este equipamento apresenta uma validade limitada na estimação
individual da composição corporal.
Palavras-chave: Atleta; Avaliação Física; Composição Corporal.It is recognized the importance of assessing body composition in athletic populations.
Therefore, it is necessary to use valid techniques for the determination of the main molecular components.
Dual-energy X-ray absorptiometry (DXA) is a precise and valid method for assessing body composition.
However, DXA is still not available at the clinical and field settings. Thus, it is important to use simple
techniques such as electrical bioimpedance analysis (BIA) but few studies validated this technique
specifically multifrequency BIA in body composition assessment in athletes. Therefore, the aim of this
research is to test the validity of multifrequency BIA (Tanita, Model MC-180) in the determination of
bone mineral content (BMC), lean soft tissue (LST) and fat mass (FM) in athletes. A total of 79 elite
athletes (35 males) were assessed by DXA and BIA. Comparison of means, concordance coefficient
correlation, multiple regression and Bland-Altman analysis were performed. Tanita explained 76%, 72%,
95% and 73% of the total variability observed from the reference method for FM (kg), FM (%), LST and
BMC, respectively. The concordance coefficient correlation for MIGO presented a substantial strength of
agreement of 0,927. However, relatively larger limits of agreement were found between BIA and DXA for
the several body components. These findings reveal that the Tanita MC-180 is a valid alternative,
particularly in the estimation of LST, in a group of athletes. However, due to the limits of agreement
obtained in the determination of the body components this equipment presents a more limited validity in
the estimation of individual body composition.
Key Words: Athletes; Physical Assessment; Body Composition
Prevalence of diabetes-associated gene variants and its association with blood glucose levels in the Algarve population, Portugal
The global rise in incidence of type 2 (T2D) has been called a pandemic, constituting a major public health concern.
Although environmental factors play a substantial role in the etiology of T2D, genetic susceptibility has been
established as a key component in T2D risk. Given the absence of studies regarding the prevalence of T2D associated
variants in the Portuguese population, our aim was to determine the prevalence of disease-associated variants and
determine its relative contribution to this phenotype. For this purpose, we have recruited 221 individuals (93 males
and 128 females), between 26-91 years old (mean age 57.1), who were enrolled in the Health Centre of S. Brás de
Alportel (Algarve). For each participant, we have measured total glucose levels and collected DNA. In addition, each
participant has answered an exhaustive questionnaire including socio-demographic information, health history and
lifestyle. We have selected and analysed three of the most significant loci previously reported to be associated with
T2D in Caucasian populations (TCF7L2 rs7903146, PARPG rs1801282 and FTO rs9939609) and performed an
association analysis between glucose levels in this population and the selected gene variants. The mean total
population glucose level was 103.85±35.3 g/dl. We found a significant difference in the mean glucose levels between
males (mean = 111.5±51.3 g/dl) and females (mean = 98.4±17.6 g/dl) (Mann-Whitney test P < 0.001). The relative
allele frequencies of the genotyped variants have been established. Genotype distribution for all investigated SNPs
was in Hardy-Weinberg equilibrium. We found a marginal association between glucose levels and genotypes at the
TCF7L2 locus (Mann-Whitney test P = 0.045) in females but not in males, with carriers of the T allele displaying
higher levels of blood glucose than homozygous for the A allele. This difference is also observed in males, although
not reaching significance. No association was found between glucose levels and the other genotyped variants. These
results suggest that the pathophysiology of the disease may be different between males and females, or that
environmental factors are influencing this trait in males. We are currently investigating the later hypothesis by
increasing our sample size and by analysing lifestyle information provided by the participants in order to evaluate
gene-environment interactions influencing glucose levels in the Portuguese population.The pilot study of the Portuguese Component of the European Health
Examination Survey (EHES) project has received funding from the European
Commission/DG Sanco (Agreement number: 20092301 – EHES JA – EAHC). This
study has also received funding from the Portuguese Foundation for Science
and Technology (FCT) (Project Reference: PTDC/SAU-ESA/101743/2008)
Prevalence of alpha-1 antitrypsin deficiency and hereditary hemochromatosis gene mutations in Algarve, Portugal
Alpha-1 antitrypsin (AAT) deficiency and hereditary hemochromatosis (HH) are two of the most fatal genetic disorders in adult life, affecting million individuals worldwide. They are often under-diagnosed conditions and diagnosis is only made when the patient is already in the advanced stages of damage. AAT deficiency results from mutations in one highly pleiomorphic gene located on chromosome 14, SERPINA 1, being Z and S mutations the most relevant clinically. These mutations will lead to an AAT deficit that compromises the lungs protection, originating emphysema, chronic bronchitis, asthma or even chronic obstructive pulmonary disease (COPD) and it is also strongly associated with various liver diseases. On the other hand, C282Y and H63D mutations in the HFE gene, located on chromosome 6, are reported to be mostly responsible for the iron accumulation in HH disorder, leading to severe damage in different organs. Disease manifestations include cirrhosis, hepatic fibrosis, diabetes mellitus, arthropathy and hepatocarcinoma.
Given the insufficient population-based information about the prevalence of these gene variants in the Portuguese population, the aim of this study was to assess their frequency in a representative sample from São Brás de Alportel, in the South of Portugal. To achieve our goal, we have genotyped a total of 208 adult subjects, including 118 females and 90 males (mean age: 58 years, range: 26-91). Regarding AAT deficiency, we found 4,3% MZ, 0,5% SS and 15,4% MS genotypes. The calculated frequency for the Z allele was 2,2% (95% CI: 0-11,7%) and for the S allele was 8,2% (95% CI: 0-17,4%). About HH, we found 1,4% C282Y/H63D, 2,4% H63D/H63D, 5,8% C282Y/N and 23,6% H63D/N genotypes. Frequencies of C282Y and H63D alleles were 3,6% (95% CI: 0-13%) and 14,9% (95% CI: 6-23,8%), respectively. The observed allele frequencies were in Hardy-Weinberg Equilibrium and no association was found with related diseases likely due to the smaller sample available.
Our findings show the highest prevalence of Z allele from SERPINA1 gene found, when compared to other populations. The remaining findings are in agreement with previously published studies. Future studies involving a larger sample size will be necessary to evaluate the penetrance of the studied gene mutations and to assess gene-environment interactions that influence disease risk, contributing to reduce the burden of these diseases which can have a great public health impact.The pilot study of the Portuguese Component of the European Health
Examination Survey (EHES) project has received funding from the European
Commission/DG Sanco (Agreement number: 20092301 – EHES JA – EAHC). This
study has also received funding from the Portuguese Foundation for Science
and Technology (FCT) (Project Reference: PTDC/SAU-ESA/101743/2008)
Genetic variation at the CY2C19 gene associated with Metabolic Syndrome susceptibility in a South Portuguese population
Metabolic syndrome (MetS) is a cluster of conditions — increased blood pressure, high blood glucose level, excess body fat around the waist and abnormal cholesterol levels — that occur together, increasing the risk of heart disease, stroke and diabetes. In Portugal, the MetS prevalence is estimated to be 27,5% with regional variations, being highest in the Alentejo (30,99%) and lowest in the Algarve (24,42%), constituting a public health problem.
Although for clinical settings, a binary definition of MetS enabling a yes or no diagnosis is useful, it is clear that dichotomizing a continuous outcome variable reduces the statistical power of the MetS association studies. Therefore, the aim of the present study is to identify genetic risk factors involved in MetS etiology, using a continuous MetS score. To achieve our goal, a principal component analysis was performed to compute a score using the six normalized risk factors for MetS (waist circumference, diastolic and systolic blood pressure, glucose, triglycerides and HDL blood levels), with a higher MetS score indicating a less favorable MetS profile. After calculating this score, an association study was performed using 37 SNPs in candidate genes involved in MetS related diseases. A total of 206 subjects, including 119 women and 87 men (mean age: 56,31± 16,37 years, range: 26-91 years) were included in this analysis. We found 4 SNPs significantly associated with higher MetS scores (rs4244285 (CYP2C19), rs279871 (GABRA2), rs1647 (NPY) and rs1142345(TPMT)). P-values are 4,36x10-4, 1,3x10-2, 1,7x10-2 and 9,76x10-3 respectively. After correcting for multiple testing only rs4244285 (CYP2C19) remains significant (p=0,016). In addition, we have performed a multiple regression analysis considering the CYP2C19 genotype as the independent variable, adjusted for age. The resulting model explains 17% of the MetS score variance. After adding the remaining SNP genotypes that do not survive the multiple testing correction, the same model is able to explain 23,1% of the score. Our findings support the evidence of an association between CYP2C19 rs4244285 gene polymorphism and the MetS score, emphasizing the importance of lipid metabolism, thought cytochrome P450 enzymes, in the MetS etiology. However, further studies will be necessary to replicate these findings in different populations as well as functional studies to clarify the role of this variant in the etiology of MetS.The pilot study of the Portuguese Component of the European Health
Examination Survey (EHES) project has received funding from the European
Commission/DG Sanco (Agreement number: 20092301 – EHES JA – EAHC). This
study has also received funding from the Portuguese Foundation for Science
and Technology (FCT) (Project Reference: PTDC/SAU-ESA/101743/2008)
Facts related to the collection of biological samples in the National Health Examination Survey - Portuguese Component of the European Health Examination Survey
Abstrat disponível em: http://www.ichg2011.org/cgi-bin/showdetail.pl?absno=11013The objective of the National Health Examination Survey (NHES), which corresponds to the Portuguese
component of the European Health Examination Survey (EHES), is to collect health data, related risk factors
and biological samples of the Portuguese population, using the EHES recommended methodology. These
surveys involve an interview, clinical and physical measurements and blood collection. In this context, we
herein describe the pilot study performed in S. Brás de Alportel in the Algarve region. For this pilot study, we
have recruited 221 individuals (95 males and 126 females), between 25 and 91 years old, who were enrolled in
the Health Centre of S. Brás de Alportel (Algarve). For each participant, we have collected 16.5 ml of total
blood, in five different Vacutainer® tubes, which was later processed into serum, plasma and DNA. We have
performed several biochemical analyses(total cholesterol, LDL,HDL, glucose, tryglicerides, creatinine, ALT,
AST, -GT, CRP and iron) and a complete blood count. From the 221 participants in this pilot study, we were
able to collect blood to 219 (99.5%). To 185 of these (84.5%) we were able to collect the total amount of blood.
The biochemical analyses were performed in all the samples. The total blood count was performed in 103
samples (47%) due to transport constraints. We have also collected DNA from 210 participants (95.9%). We
have created a biobank comprising 1847 serum aliquots and 959 plasma aliquots, which have been stored at -
80°C and 210 DNA aliquots which have been stored at 4°C. In conclusion, during this study, we have
optimized the logistics and procedures to perform the large scale study for the NHES and EHES. In addition,
we have created a biobank comprising detailed questionnaire data, physical and clinical data and biological
samples from a representative sample of S. Brás de Alportel in Algarve, Portugal. This biobank will allow us to
perform future studies, including the determination of the prevalence of gene variants of public health interest,
the characterization of gene-environment interactions in the development of chronic diseases and the genetic
structure of the Portuguese population. The success rate, the quality of the data and of the biological samples
was high and comparable to similar studies.Fundação para a Ciência e Tecnologia e European Commission/DG Sanc
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