May the polymorphisms of iron metabolism modulate metabolic and bone remodelling parameters associated with osteoporosis?

Introduction:- Osteoporosis is a multifactorial disease whose interaction between genetic and environmental factors lead to a reduction of bone mineral density accompanied by changes in bone microarchitecture level, leading to a significant decrease in bone strength and an increased fracture risk. - Iron is known to play a relevant role in the development of osteoporosis as it suppresses osteoblast formation and may also stimulate osteoclast resorption of bone. As so, polymorphisms in genes affecting iron homeostasis can increase the susceptibility for the development of osteoporosis. - HFE is a major histocompatibility complex class I-like protein which gene is commonly mutated in Hereditary Hemochromatosis, a disorder characterized by excessive intestinal iron absorption and its deposition in several organs. It has been postulated that HFE may contribute to iron metabolism regulation by activating hepcidin synthesis in hepatocytes and regulating the expression of iron metabolism-related genes (ferroportin) in duodenum and other cells. - The locus encoding HFE is located on the long arm of chromosome 6 (6q22.2) and contains 2 major polymorphisms. A 845G-A transition resulting in a cys282-to-tyr (C282Y) substitution and a C-to-G transversion in exon 2 resulting in a his63-to-asp substitution (H63D). - Haptoglobin (Hp) is an acute phase protein that binds free hemoglobin (Hb) released from erythrocytes with high affinity and thereby inhibits its oxidative activity. - The locus encoding haptoglobin is located on the long arm of chromosome 16 (16q22.2) and presents a copy number variation polymorphism (CNV) that results from an internal duplication of a gene segment (exons 3 and 4). This gives rise to three different genotypes (Hp1.1, Hp 2.1 and Hp2.2) that modulate the half-life of Hp-Hb complex, its plasma concentration as well as other functions (angiogenesis, immune, etc

Susceptibilité accrue des athlètes au stress oxydant : réalité ou mythe? Étude chez des nageurs

© 2020 Elsevier Masson SAS. All rights reservedAims. — Exercise is associated with accelerated reactive oxygen species (ROS) generation and stimulation of the antioxidant defences (AD). In high intensity exercise ROS production may overwhelm the AD and induce adverse effects on health and performance. We aim to investigate the redox balance of adult-competitive swimmers against recreational exercise practitioners. Methods. — Fifteen high-competition male swimmers (S) and 16 active men (AM), all aged between 18—25 years, participated in the study. Venous blood was collected at rest in the morning to assess oxidative and muscle damage markers, antioxidant enzymatic activities in erythrocytes, and non-enzymatic antioxidants in plasma. All parameters were assessed by photometry with the exception of thiobarbituric acid reactive substances (TBARS), assessed by fluorimetry. Bivariate correlations were performed to investigate the association between all redox balance markers. Partial correlation analysis was conducted to control for the exercise level. Results. — Differences between groups were observed in red blood cells peroxidation (RBCPx—S: 39.2 ± 4.8; AM: 46.3 ± 9.5%) and in meta-hemoglobin reductase (RmHb — S: 7.5 ± 2.1; AM: 9.1 ± 2.3mol/min.gHb), with S presenting lower mean values (P < 0.05). Controlling for the exercise level, adrenaline oxidase (AdOx) was inversely correlated with carotenoids (R = −0.596; P = 0.001) and directly with creatine kinase (CK) (R = 0.413; P = 0.045) and with TBARS (R = 0.532; P = 0.005); RBCPx was inversely correlated with acid phosphatase (ACP1) (R = −0.392; P = 0.048) and directly with glutathione reductase (GR) (R = 0.524; P = 0.006); GR was inversely correlated with TBARS (R = −0.404; P = 0.041); VitE was directly correlated with Carotenoids (R = 0.723; P = 0.001) and inversely with TBARS (R = 0.543; P = 0.004). Therefore: AD are effective at controlling ROS; VitE and carotenoids are important protective lipid antioxidants; higher TBARS may be associated to the stimulation of GR activity; muscle leakages associated to the AdOx activity which may result from ion leakage, intravascular hemolysis or inflammation. Conclusion. — Our results suggest that competitive swimmers are not at higher risk of oxidative damage than recreational exercise practitioners.info:eu-repo/semantics/publishedVersio

Genetic toxicology of flavonoids : the role of metabolic conditions in the induction of reverse mutation, SOS functions and sister-chromatid exchanges

Glycosides of flavonols such as quercetin, are found in the edible portions of most food vegetables. Flavonols present in plants as glycosides can be freed during fermentation. We have compared the DNA-damaging activity of quercetin, rutin (3-o-rutinoside of quercetin) and a fermented flavonoid-containing beverage, red wine, for different genetic end-points under different metabolic conditions. The genotoxicity of quercetin, rutin and commercial red wine has been studied for the induction of: (i) reverse mutation in the Ames assay; (ii) SOS functions in the SOS Chromotest; (iii) sister-chro-matid exchanges (SCEs) in human lymphocytes. While in the Ames assay the mutagenicity of quercetin is enhanced by the presence of rat liver microsomal enzymes (S9) or the respective cytosolic fraction (S100), genotoxicity is reduced when the induction of SOS responses is assessed using the SOS Chromotest. Similarly, the induction of SCEs is lowered when testing in the presence of liver enzymes. Rutin has no activity whatsoever. Detection of activity of red wine in the three assays is not dependent upon hydrolysis by glycosidases and its content of quercetin accounts almost entirely for the levels of genotoxicity detected. The results suggest that the putative genotoxic metabolites of quercetin vary for different genetic end-points considered and that the metabolic fate of flavonoids might partly account for the conflicting data about their genotoxicity in vivo and carcinogenic activity.The advice of Professor M. Hofnung during this study is gratefully acknowledged. Our appreciation is extended to Dr P. Quiilardet for his invaluable suggestions. This work was supported in part by the National Institute of Scientific Investigation (INIC) through research contract no. 85/CSA/16.info:eu-repo/semantics/publishedVersio

Osteoporosis: gene interaction between haptoglobin and HFE polymorphisms

Osteoporosis is a common metabolic bone disease characterized by reduced bone mass and increased risk of fragility fractures. The pathogenesis of this disease is complex and influenced by multiple risk factors, where genetic factors play an important role. Osteoporosis and iron metabolism have an important relationship. Iron overload suppresses osteoblast formation and also stimulate osteoclast resorption of bone, suggesting that polymorphisms in genes affecting iron homeostasis can increase the susceptibility for the development of osteoporosis. In the present study, we aimed to analyse the epistatic relationship between two iron metabolism related genes - haptoglobin (Hp) and HFE – in osteoporosis. To achieve this, 313 patients with osteoporosis and 450 controls with normal bone mineral density were enrolled. Haptoglobin phenotype was determined by polyacrylamide gel electrophoresis (PAGE) and HFE polymorphisms (H63D and C282Y) were evaluated by PCR-RFLP. All statistical tests were performed with SPSS 24.0 software. Results showed that, no significant differences were found between the two populations (patients vs controls) concerning Hp phenotypes or HFE (H63D and C282Y) genotypes. However, individuals that have co-inherited the Hp 2.2 and the HFE_H63D HH have an increased risk for developing osteoporosis [p=0.049; OR (95% CI) = 2.509 (1.003-6.279)] (adjusted for age and body mass index). In summary, a significant epistatic interaction was detected between haptoglobin and HFE and osteoporosis, where Hp 2.2 in combination with HFE_H63D HH genotype appear to increase the risk for developing osteoporosis. Since these genes are related to iron metabolism, the results of this study reinforce an important action of this metabolism in the development of osteoporosis.info:eu-repo/semantics/publishedVersio

External climate data extraction using the forward feature selection method in the context of occupational safety

Global climate changes and the increase in average temperatures are some of the major contemporary problems that have not been considered in the context of external factors to increase accident risk. Studies that include climate information as a safety parameter in machine learning models designed to predict the occurrence of accidents are not usual. This study aims to create a dataset with the most relevant climatic elements, to get better predictions. The results will be applied in future studies to correlate with the accident history in a retail sector company to understand its impact on accident risk. The information was collected from the National Oceanic and Atmospheric Administration (NOAA) climate database and computed by a wrapper method to ensure the selection of the most features. The main goal is to retain all the features in the dataset without causing significant negative impacts on the prediction score.This work has been supported by FCT—Fundação para a Ciência e Tecnologia within the Project Scope UIDB/05757/2020 and NORTE-01-0247-FEDER 072598 iSafety: Intelligent system for occupational safety and well-being in the retail sector.info:eu-repo/semantics/publishedVersio

Integrated feature selection and classification algorithm in the prediction of work-related accidents in the retail sector: a comparative study

Assessing the different factors that contribute to accidents in the workplace is essential to ensure the safety and well-being of employees. Given the importance of risk identification in hazard prediction, this work proposes a comparative study between different feature selection techniques (χ2 test and Forward Feature Selection) combined with learning algorithms (Support Vector Machine, Random Forest, and Naive Bayes), both applied to a database of a leading company in the retail sector, in Portugal. The goal is to conclude which factors of each database have the most significant impact on the occurrence of accidents. Initial databases include accident records, ergonomic workplace analysis, hazard intervention and risk assessment, climate databases, and holiday records. Each method was evaluated based on its accuracy in the forecast of the occurrence of the accident. The results showed that the Forward Feature Selection-Random Forest pair performed better among the assessed combinations, considering the case study database. In addition, data from accident records and ergonomic workplace analysis have the largest number of features with the most significant predictive impact on accident prediction. Future studies will be carried out to evaluate factors from other databases that may have meaningful information for predicting accidents.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES (PIDDAC) to CeDRI (UIDB/05757/2020 and UIDP/05757/2020) and SusTEC (LA/P/0007/2021). This work has been supported by NORTE-01-0247-FEDER-072598 iSafety: Intelligent system for occupational safety and well-being in the retail sector. Inês Sena was supported by FCT PhD grant UI/BD/153348/2022

Comparison of immunohematological profile between endurance- and power-oriented elite athletes

There is general perception that elite athletes are highly susceptible to changes in immunohematological profile. The objective of this study was to compare immunohematological parameters of elite athletes of different aerobic and muscular strength sports and analyze changes over 2 months. Sixteen judoists and 14 swimmers were evaluated 2 months before (M1) and immediately prior to competition (M2). Hemogram and lymphocytes subpopulations were assessed with automatic counter and flow cytometry, respectively. Judoists had higher neutrophils and lower monocytes and eosinophils percentages than swimmers at M1 and M2. At M2 judoists had lower red blood cells (RBC), hemoglobin, and hematocrit than swimmers. At M2 judoists' hematocrit and CD16 decreased while swimmers' hemoglobin and hematocrit increased. In conclusion, neither sports characteristics nor intense training seem to displace the athletes' immunohematological profile out of the clinical range, despite the possibility of occurrence of microlesions that may stimulate production of leukocytes and reduction of RBC in judoists.Les athlètes d’élite seraient, selon l’impression générale, très prédisposés aux changements du profil immunohématologique. Cette étude a pour objectif de comparer les paramètres immunohématologiques d’athlètes d’élite de divers sports a` dominante aérobie et de force musculaire et d’analyser les changements en deux mois. On évalue 16 judokas et 14 nageurs 2 mois avant (M1) et immédiatement avant la compétition (M2). On évalue l’hémogramme et les sous-populations de lymphocytes par comptage automatique et cytométrie en flux, respectivement. À M1 et M2, les judokas présentent un plus haut pourcentage de neutrophiles et un plus faible pourcentage de monocytes et d’éosinophiles que les nageurs. À M2, les judokas ont moins de globules rouges, d’hémoglobine et un plus faible hématocrite que les nageurs. À M2, l’hématocrite et le nombre de CD16 des judokas diminuent alors que, chez les nageurs, l’hémoglobine et l’hématocrite augmentent. En conclusion, les caractéristiques du sport et l’entraînement intensif ne semblent pas déplacer le profil immunohématologique des athlètes a` l’écart des valeurs cliniques, et ce, malgré la possibilité de l’occurrence de microlésions pouvant stimuler la production de leucocytes et la diminution des globules rouges chez les judokas. [Traduit par la Rédaction]José P. Morgado and Catarina N. Matias were supported by the Portuguese Foundation for Science and Technology (SFRH/BD/48211/2008 and SFRH/BD/61520/2009, respectively).info:eu-repo/semantics/publishedVersio

CoReumaPt protocol: The Portuguese cohort of rheumatic diseases

Introduction: Rheumatic diseases (RD) are conditions with a variety of clinical manifestations and prognosis influenced by several factors. Cohorts and registries have been already established in some countries and have contributed to important knowledge about the disease course and the long-term outcomes of RD. This paper introduces the CoReumaPt project and sets the first step towards the creation of a prospective cohort study including the main RD occurring in the Portuguese population. CoReumaPt will allow outcomes research of chronic RD and the assessment of factors influencing the development and progression of RD. It will also allow to further evaluate the economic impact and the burden of RD in Portugal. CoReumaPt will be linked to Reuma.pt, the National Register of Rheumatic Diseases from the Portuguese Society of Rheumatology. Methods: An open cohort will be created, initially composed by the randomly selected population of the crosssectional National Epidemiological Rheumatic Diseases study (EpiReumaPt) and afterwards by other sources, namely through self- and physician's referral. Follow--up with annual self-administered questionnaires will be performed, in order to systematically collect and analyze outcomes of interest, mainly patient-reported outcomes. Data concerning less frequent assessments, such as radiographs and biomarkers, will also be assembled. Conclusions: CoReumaPt will be a valuable resource for scientific research and will deliver pivotal information to improve public health policies concerning the prevention and the management of RD in Portugal.publishersversionpublishe