14 research outputs found
Ătude de variations gĂ©nĂ©tiques et Ă©pigĂ©nĂ©tiques de gĂšnes candidats des complications mĂ©taboliques de l'obĂ©sitĂ©
LâobĂ©sitĂ© est de nos jours un problĂšme croissant Ă travers le monde. La morbiditĂ© qui y est associĂ©e est surtout reliĂ©e au dĂ©veloppement des diffĂ©rentes composantes du syndrome mĂ©tabolique (SMet), une constellation de facteurs de risque regroupant lâhypertension, la dyslipidĂ©mie (concentration faible de cholestĂ©rol des lipoprotĂ©ines Ă haute densitĂ© (C-HDL) et Ă©levĂ©e de triglycĂ©rides (TG)), lâhyperglycĂ©mie et lâobĂ©sitĂ©. Cependant, certains sujets obĂšses demeurent mĂ©taboliquement sains. Les facteurs gĂ©nĂ©tiques joueraient donc un rĂŽle important dans le dĂ©veloppement de lâobĂ©sitĂ© et de ses complications. Les facteurs Ă©pigĂ©nĂ©tiques semblent Ă©galement y avoir des effets. Lâanalyse de tissu adipeux viscĂ©ral (TAV) a donc Ă©tĂ© rĂ©alisĂ©e pour mener Ă la dĂ©couverte de plusieurs gĂšnes diffĂ©rentiellement exprimĂ©s et mĂ©thylĂ©s entre les obĂšses atteints et non atteints par le SMet. Les deux gĂšnes candidats NMT1 et DGKZ font partie de ce groupe et leurs associations avec les composantes du SMet ont Ă©tĂ© testĂ©es. Leurs niveaux de mĂ©thylation et dâexpression gĂ©nique ont aussi Ă©tĂ© analysĂ©s.Obesity is now a major problem worldwide. Its associated morbidity is mostly related to the components of metabolic syndrome (MetS), a constellation of risk factors including hypertension, dyslipidemia (low HDL-C concentration and high concentration of TG), hyperglycemia and obesity. However, some obese subjects remain metabolically healthy. Genetic has thus been established as playing a major role in the development of obesity and its complications. Epigenetic factors may also be involved. The analysis of visceral adipose tissue (VAT) was thus done and led to the discovery of several differentially expressed and methylated genes between groups of obese affected and unaffected with MetS. The two candidate genes NMT1 and DGKZ were part of these and their associations with components of MetS were tested, as well as their methylation and expression levels
Effect of linking arm hydrophilic/hydrophobic nature, length and end-group on the conformation and the RGD accessibility of surface-immobilized fibronectin
In order to stimulate the cellular response to implant materials, extracellular matrix (ECM)
proteins, such as collagen and fibronectin (FN), are immobilized on the implant surface.
Amongst all ECM proteins used for biomimetic materials for medical applications, FN is one of
the most investigated proteins thanks to its ability to promote cell adhesion and its contribution
to important physiological processes. However, its conformation and hence its bioactivity
strongly depend on the hydrophilic/hydrophobic nature of the surface as well as on immobilization strategies. This work investigates the effect of these two parameters, as well as
the effect of the crosslinker length. FN was grafted onto silicon wafers using eights different
linking arms presenting different lengths, hydrophilic/hydrophobic characters and binding sites.
The protein was linked through either its amino groups (lysine amino acids) or sulfhydryl
functionalities (cysteine amino acids). The grafting of each crosslinker and subsequent FN
conjugation onto the surfaces was evidenced by X-ray photoelectron spectroscopy, while the
surface hydrophilicity was determined by contact angle measurements. Moreover, atomic force
microscopy images revealed that the conformation of surface conjugated FN only depends on
the hydrophilicity of the linking arm. The FN conformation was also probed by enzyme-linked
immunosorbent assays (ELISA). ELISA data demonstrated that all of the three investigated
parameters linking arm parameter (length, hydrophobic/hydrophilic character, and terminal
end-group) somewhat influence the RGD accessibility
The rare allele of DGKZ SNP rs10838599 is associated with variability in HDL-cholesterol levels among severely obese patients
Introduction: Diacylglycerol kinase-zeta, one of the ten isoforms of DGKs expressed in mammals is an important enzyme of lipid metabolism. It catalyzes the
interconversion of diacylglycerol and phosphatidic acid, two major second messengers. Its gene DGKZ has been previously identified as being overexpressed and
undermethylated in visceral adipose tissue of patients with (MetS+) versus without (MetS-) the metabolic syndrome (MetS).
Objective: The aim of this study was to investigate the associations between DGKZ gene polymorphisms (SNPs) and phenotypes related to MetS (BMI, waist girth,
CRP, fasting glucose, lipid profile (triglycerides, total-cholesterol, LDL-cholesterol and HDL-cholesterol (HDL-C)), resting systolic and diastolic blood pressures).
Methods: The study sample included 1752 severely obese participants who underwent bariatric surgery. Associations between the five selected tSNPs of DGKZ
and features of the MetS were tested. The effects of these SNPs on DGKZ methylation and expression levels were tested in subgroups of 32 and 14 obese subjects,
respectively. Correlations between methylation and expression levels were also computed.
Results: Homozygotes for the rare allele of rs10838599 displayed higher plasma HDL-C concentrations compared to the other genotype groups (p=0.03). For
gene methylation, only a trend with the cg05412031 CpG site (p=0.09) was found for the single significantly phenotype-associated SNP. There was no significant
correlation between DGKZ methylation at cg05412031 and expression levels.
Conclusion: These results suggest that DGKZ SNP rs10838599 modulates plasma HDL-C levels thereby its gene contributes to the inter-individual variability
observed in the cardiometabolic risk profile of patients with severe obesity
Impact of NMT1 gene polymorphisms on features of the metabolic syndrome among severely obese patients
Introduction: N-myristoyltransferase (NMT) is implicated in myristoylation, required for biological activities of several proteins. Its gene N-myristoyltransferase 1 (NMT1) has been found
to be overexpressed and hypermethylated in Visceral Adipose Tissue (VAT) of severely obese
individuals with Metabolic Syndrome (MetS+) versus without (MetS-).
Objective: The aim of this study was to verify the associations between NMT1 gene polymorphisms Single Nucleotide Polymorphisms (SNPs) and metabolic complications among obese
subjects.
Methods: Associations between SNPs and determinants of MetS were tested with 1752 obese
participants undergoing a bariatric surgery. The effect of selected SNPs on methylation, and
correlation with expression levels of NMT1 were verified in subgroups.
Results: Rs2239921 was significantly associated with systolic (p=0.03) and diastolic (p<0.0001)
blood pressures. Rs2239923 was associated with plasma High Density Lipoprotein-Cholesterol
or HDL-Cholesterol (HDL-C) levels (p=0.05), while rs2269746 was associated with Low Density Lipoprotein-Cholesterol or LDL-Cholesterol (LDL-C) (p=0.006) and Total-Cholesterol
(Total-C) levels (p=0.004). Rs1005136 (p=0.03), rs8066395 (p=0.03) or rs2157840 (p=0.04)
were associated with plasma concentrations of C-Reactive Protein (CRP). Phenotype-associated SNPs were associated with NMT1 methylation levels of six CpG sites. NMT1 methylation
levels of one CpG site, cg10755730, correlated with gene expression levels (r=0.57; p=0.04).
Conclusion: These results suggest that the presence of NMT1 SNPs is associated with altered
plasma lipid levels as well as with increased inflammation markers and blood pressure among
severely obese patients
Genetic evidence supports the development of SLC26A9 targeting therapies for the treatment of lung disease
Over 400 variants in the cystic fibrosis (CF) transmembrane conductance regulator (CFTR) are CF-causing. CFTR modulators target variants to improve lung function, but marked variability in response exists and current therapies do not address all CF-causing variants highlighting unmet needs. Alternative epithelial ion channel/transporters such as SLC26A9 could compensate for CFTR dysfunction, providing therapeutic targets that may benefit all individuals with CF. We investigate the relationship between rs7512462, a marker of SLC26A9 activity, and lung function pre- and post-treatment with CFTR modulators in Canadian and US CF cohorts, in the general population, and in those with chronic obstructive pulmonary disease (COPD). Rs7512462 CC genotype is associated with greater lung function in CF individuals with minimal function variants (for which there are currently no approved therapies; p = 0.008); and for gating (p = 0.033) and p.Phe508del/ p.Phe508del (p = 0.006) genotypes upon treatment with CFTR modulators. In parallel, human nasal epithelia with CC and p.Phe508del/p.Phe508del after Ussing chamber analysis of a combination of approved and experimental modulator treatments show greater CFTR function (p = 0.0022). Beyond CF, rs7512462 is associated with peak expiratory flow in a meta-analysis of the UK Biobank and Spirometa Consortium (p = 2.74 Ă 10â44) and provides p = 0.0891 in an analysis of COPD case-control status in the UK Biobank defined by spirometry. These findings support SLC26A9 as a therapeutic target to improve lung function for all people with CF and in individuals with other obstructive lung diseases
Factors Associated with Eating in the Absence of Hunger among Children and Adolescents: A Systematic Review
Eating in the absence of hunger (EAH) has been extensively studied over the past two decades and has been associated with excess body weight and the development of obesity. However, determinants of EAH remain uncertain. This systematic review aims to identify individual, familial, and environmental factors associated with EAH among children and adolescents. We included studies with a measure of EAH in participants aged 3–17 years old and including ≥1 factor associated with EAH. Our search identified 1494 articles. Of these, we included 81 studies: 53 cross-sectional, 19 longitudinal and nine intervention studies. In childhood (≤12 years old), EAH increases with age, it is greater in boys compared to girls, and it is positively associated with adiposity. Moreover, EAH development seems to be influenced by genetics. In adolescence, the number of studies is limited; yet, studies show that EAH slightly increases or remains stable with age, is not clearly different between sexes, and findings for overweight or obesity are less consistent across studies in adolescence. For familial factors, parental restrictive feeding practices are positively associated with EAH during childhood, mostly for girls. Studies assessing environmental factors are lacking and robust longitudinal studies spanning from early childhood to adolescence are needed
Des outils multimédias en ligne pour apprendre des concepts enmathématiques
SAMI-PersĂ©vĂ©rance est un dispositif dâaide en ligne qui offre, entre autres, des outils dâaide en mathĂ©matiques au niveau postsecondaire. Les Ă©tudiants peuvent accĂ©der aux outils dâaide par les moyens suivants : par mots-clĂ©s, par carte conceptuelle ou par lâoutil de dĂ©pistage des difficultĂ©s en mathĂ©matiques. Les donnĂ©es recueillies dans le dispositif rĂ©vĂšlent que 4 773 choix dâoutils dâaide ont Ă©tĂ© faits (par lâoutil de dĂ©pistage dans 72 % des cas), 2 873 énoncĂ©s de difficultĂ©s ont Ă©tĂ© cochĂ©s, et deux questionnaires sur la dyscalculie ont prĂ©sentĂ© un rĂ©sultat positif. Ces donnĂ©es laissent supposer que les Ă©tudiants ont apprĂ©ciĂ© ces outils qui leur ont permis de connaĂźtre leurs faiblesses et de mieux comprendre les notions de base en mathĂ©matiques.SAMI-PersĂ©vĂ©rance is an online device that offers help in postsecondary mathematics. Students can access help through the following tools: a keyword search, a concept map, or the math difficulties screening tool. Data collected from the device revealed that 4,773 tool selections were made (72% of the cases were proposed by the screening tool), 2,873 statements of difficulties were checked, and 2 dyscalculia questionnaires showed a positive result. These data suggest that students enjoyed these tools, which allowed them to identify their weaknesses and to understand basic concepts in mathematics
Lâalimentation en pleine conscience pour le traitement du trouble dâaccĂšs hyperphagique
Cet article discute du recours Ă lâalimentation en pleine conscience comme approche thĂ©rapeutique du trouble dâaccĂšs hyperphagique. CaractĂ©risĂ© par la consommation de grandes quantitĂ©s de nourriture dans un court laps de temps, ce trouble des conduites alimentaires, le plus prĂ©valent dâailleurs, sâaccompagne dâun sentiment de perte de contrĂŽle sur la prise alimentaire et dâune dĂ©tresse importante. Cette approche donne des rĂ©sultats positifs en diminuant la frĂ©quence des accĂšs hyperphagiques (AH) et la quantitĂ© dâaliments consommĂ©s lors dâun AH. Elle intervient sur les trois principaux dĂ©clencheurs dâAH : la restriction alimentaire, la restriction cognitive et les envies de manger Ă©motionnelles. La pratique quotidienne et soutenue de la mĂ©ditation en pleine conscience est le plus important prĂ©dicteur des bienfaits. Elle favorise chez la personne qui la pratique la reconnaissance des signaux de la faim et de la satiĂ©tĂ© permettant ainsi de mieux rĂ©guler les apports Ă©nergĂ©tiques; elle lĂšve les restrictions alimentaires favorisant la reconnaissance des prĂ©fĂ©rences alimentaires et la satisfaction sensorielle; finalement, elle dĂ©veloppe la conscience corporelle et lâaptitude Ă reconnaĂźtre les envies de manger Ă©motionnelles qui permettra de diminuer progressivement lâalimentation Ă©motionnelle. Puisque le champ dâexercices des diĂ©tĂ©tistes-nutritionnistes nâenglobe pas la modification du fonctionnement Ă©motionnel du client ou de la cliente, une collaboration interprofessionnelle est grandement souhaitable
Quelles sont les stratégies d'apprentissage que les étudiants universitaires ayant un ou des troubles d'apprentissage ou un déficit d'attention doivent apprendre à utiliser?
Au QuĂ©bec, la prĂ©sence dâĂ©tudiants ayant un ou des troubles dâapprentissage
(TA) ou un trouble du dĂ©ficit dâattention avec ou sans hyperactivitĂ© (TDA/H) est de
plus en plus marquĂ©e dans nos universitĂ©s. Afin dâaider ces Ă©tudiants Ă persĂ©vĂ©rer
dans leur cheminement universitaire, nous avons voulu connaßtre les difficultés particuliÚres
quâils Ă©prouvent sur le plan des stratĂ©gies dâapprentissage afin de pouvoir
les soutenir dâune façon plus ciblĂ©e. Pendant trois sessions dâĂ©tudes, 205 Ă©tudiants
ont expĂ©rimentĂ© un dispositif dâaide Ă la persĂ©vĂ©rance aux Ă©tudes, SAMIPersĂ©vĂ©rance,
afin de cerner les difficultĂ©s quâils rencontraient. Les traces laissĂ©es
dans le dispositif ont permis de dĂ©terminer les stratĂ©gies dâapprentissage les moins
utilisées autant par les étudiants ayant un TA et ceux ayant un TDA/H que les étudiants
ayant les deux types de troubles. Parmi les stratĂ©gies dâapprentissage, ce sont
les stratégies de lecture, de production écrite, de gestion de la mémorisation, de gestion
du temps et de gestion du stress qui semblent les moins utilisées par ces étudiants.
Enfin, les étudiants semblent avoir recours à des stratégies de production
orale et de gestion de leurs Ă©motions