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1.
Epigenetics ; 15(3): 323-335, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31510847

RESUMO

Studies have linked maternal pre-pregnancy obesity and hyperglycaemia with metabolic and neurodevelopmental complications in childhood. DNA methylation (DNAm) might enable foetal adaptations to environmental adversities through important gene loci. NEGR1 is involved in both energy balance and behaviour regulation. The aim of this study was to investigate associations between placental DNAm at the NEGR1 gene locus and childhood anthropometric and neurodevelopmental profiles in preschoolers. We analysed 276 mother-child dyads from Gen3G, a prospective birth cohort from Sherbrooke. At 3yo (40.4 ± 3.0 months), we measured body mass index (BMI) and the mothers reported on offspring neurobehavior using the Strengths and Difficulties Questionnaire (SDQ). We quantified DNAm levels at 30 CpGs at the NEGR1 locus using the MethylationEPIC Array in placental biopsies. DNAm at four CpGs located before NEGR1 second exon predicted child's BMI z-score (cg26153364: ß=-0.16 ± 0.04; p=0.008, cg23166710: ß=0.14 ± 0.08; p=0.03) and SDQ total score (cg04932878: ß=0.22 ± 1.0; p= 3.0x10-4, cg16525738: ß=-0.14 ± 0.18; p=0.01, cg23166710: ß=-0.13 ± 0.36; p= 0.04), explaining 4.2% (p=0.003) and 7.3% (p= 1.3 x 10-4) of BMI-z and SDQ variances. cg23166710 was associated with both childhood phenotypes and correlated with NEGR1 placental expression (r=-0.22, p=0.04), suggesting its possible functional role. Together, maternal metabolic characteristics during pregnancy with NEGR1 DNAm levels explained 7.4% (p=4.2 x 10-4) of BMI-z and 14.2% (p=2.8 x 10-7) of SDQ variance at 3yo. This longitudinal study suggests that placental NEGR1 DNAm is associated with adiposity and neurodevelopment in preschool children and highlights its potential role in their comorbidity.


Assuntos
Índice de Massa Corporal , Moléculas de Adesão Celular Neuronais/genética , Desenvolvimento Infantil , Metilação de DNA , Placenta/metabolismo , Adulto , Pré-Escolar , Epigênese Genética , Feminino , Proteínas Ligadas por GPI/genética , Humanos , Recém-Nascido , Masculino , Testes Neuropsicológicos , Gravidez
2.
Nutr Metab Cardiovasc Dis ; 29(7): 684-691, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31078363

RESUMO

BACKGROUND AND AIMS: The "Life's Simple 7" (LS7) metrics were developed by the American Heart Association (AHA) to assess and promote cardiovascular health in the American population. The purpose of this study was to assess the overall cardiovascular health of French-speaking adults from the Province of Quebec using the LS7 score. METHODS AND RESULTS: A total of 777 age and sex-representative participants of five different administrative regions in the Province of Quebec (387 men and 390 women; mean age ± SEM: 41.9 ± 0.1 years) were included in these analyses. Metrics of the LS7 score (smoking, physical activity, diet, body mass index, blood pressure, fasting total cholesterol and blood glucose) were analysed to generate a final score ranging from 0 to 7. Only 0.5% of participants met all criteria for ideal cardiovascular health. The diet metric showed the lowest prevalence of "ideal" scores (4.8%) whereas not smoking was the metric with the highest prevalence (88.1%). Women had a higher LS7 score than men, while age and education level (negative and positive association, respectively; p < 0.0001) were also associated with the LS7 score. CONCLUSION: Consistent with studies conducted among other populations, very few French-speaking adults from the Province of Quebec achieve an ideal cardiovascular health. These data indicate that further public health efforts aimed at promoting the LS7 metrics, focusing primarily on diet, are urgently needed. Specific groups, including older adults and those with lower levels of education, should be targeted when developing cardiovascular health promotion interventions.


Assuntos
American Heart Association , Doenças Cardiovasculares/prevenção & controle , Indicadores Básicos de Saúde , Nível de Saúde , Estilo de Vida Saudável , Idioma , Prevenção Primária , Comportamento de Redução do Risco , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Glicemia/análise , Pressão Sanguínea , Índice de Massa Corporal , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Colesterol/sangue , Estudos Transversais , Exercício Físico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Proteção , Quebeque/epidemiologia , Medição de Risco , Fatores de Risco , Abandono do Hábito de Fumar , Estados Unidos , Adulto Jovem
3.
Int J Obes (Lond) ; 42(4): 775-784, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28990592

RESUMO

BACKGROUND: Clinical recommendations to limit gestational weight gain (GWG) imply high GWG is causally related to adverse outcomes in mother or offspring, but GWG is the sum of several inter-related complex phenotypes (maternal fat deposition and vascular expansion, placenta, amniotic fluid and fetal growth). Understanding the genetic contribution to GWG could help clarify the potential effect of its different components on maternal and offspring health. Here we explore the genetic contribution to total, early and late GWG. PARTICIPANTS AND METHODS: A genome-wide association study was used to identify maternal and fetal variants contributing to GWG in up to 10 543 mothers and 16 317 offspring of European origin, with replication in 10 660 mothers and 7561 offspring. Additional analyses determined the proportion of variability in GWG from maternal and fetal common genetic variants and the overlap of established genome-wide significant variants for phenotypes relevant to GWG (for example, maternal body mass index (BMI) and glucose, birth weight). RESULTS: Approximately 20% of the variability in GWG was tagged by common maternal genetic variants, and the fetal genome made a surprisingly minor contribution to explain variation in GWG. Variants near the pregnancy-specific beta-1 glycoprotein 5 (PSG5) gene reached genome-wide significance (P=1.71 × 10-8) for total GWG in the offspring genome, but did not replicate. Some established variants associated with increased BMI, fasting glucose and type 2 diabetes were associated with lower early, and higher later GWG. Maternal variants related to higher systolic blood pressure were related to lower late GWG. Established maternal and fetal birth weight variants were largely unrelated to GWG. CONCLUSIONS: We found a modest contribution of maternal common variants to GWG and some overlap of maternal BMI, glucose and type 2 diabetes variants with GWG. These findings suggest that associations between GWG and later offspring/maternal outcomes may be due to the relationship of maternal BMI and diabetes with GWG.


Assuntos
Feto/fisiologia , Ganho de Peso na Gestação/genética , Gravidez/genética , Feminino , Estudo de Associação Genômica Ampla , Ganho de Peso na Gestação/fisiologia , Humanos , Gravidez/fisiologia , Gravidez/estatística & dados numéricos
4.
J Gynecol Obstet Biol Reprod (Paris) ; 45(8): 796-808, 2016 Oct.
Artigo em Francês | MEDLINE | ID: mdl-27388468

RESUMO

The intimate and sexual dimension of future and new parenting couples' relationship is the most affected and the most vulnerable during the transition to parenthood; couples must adapt to support their relationship and their families. The purpose of this scoping review is to identify the literature that has been published on perinatal sexuality in the last 15 years. A total of 123 empirical articles were selected. This first article of a series of two is about sexuality during pregnancy. In addition to painting a picture from the chosen articles, 23 prenatal sexual variables were analyzed. The combined data present a diversified portrait of perinatal sexuality during pregnancy: the intimate and sexual experience varies during this period. Despite some exceptions, a certain tendency towards a gradual and progressive decline in most sexual behaviors and overall sexual expression during pregnancy was noted, with a marked decrease in early pregnancy and during the third trimester. Women are particularly affected by a greater number of sexual changes, but men are too. Many simultaneous physiological and psychological factors affect the sexual expression of the couples. Sexual fluctuations are a natural phenomenon during the transition to parenthood; couples must adjust to the new conditions and to the changes associated with sexuality during pregnancy, which are considered temporary. Sexoperinatal interventions should be a part of holistic perinatal health care in order to help couples maintain an intimate relationship and a healthy and positive sexual life.


Assuntos
Gravidez/fisiologia , Gravidez/psicologia , Comportamento Sexual/fisiologia , Comportamento Sexual/psicologia , Parceiros Sexuais/psicologia , Feminino , Humanos , Masculino
5.
J Gynecol Obstet Biol Reprod (Paris) ; 45(8): 809-820, 2016 Oct.
Artigo em Francês | MEDLINE | ID: mdl-26989006

RESUMO

The intimate and sexual dimension of future and new parenting couples' relationship is the most affected and the most vulnerable during the transition to parenthood. The purpose of this scoping review is to present the portrait of perinatal sexuality through 123 empirical articles published in the last 15 years. This second article in a series of two is about sexuality during labor and birth, during the postpartum, and in relation to breastfeeding. A total of 29 sexual variables were analyzed. Sexuality during the intrapartal and postnatal periods is very diversified. Some recurring items, however, can be identified: a period of non-sexuality in the first postnatal months, followed by a gradual return of sexuality from 3 to 6 months postpartum and continuing until 12 months or more. Sexuality during the intrapartum is considered taboo and couples' experiences can be at opposite ends: some couples' experiences are sensual and erotic during childbirth, while others experience birth trauma with a negative sexual impact postnatally. Sexuality during breastfeeding is also taboo with a negative impact on women's sexuality. In all of these circumstances, women's and men's sexuality are affected and a multitude of simultaneous physiological and psychological factors affect their experiences. Fluctuations in the intimate and sexual dimensions of the conjugal relationship are considered as a natural phenomenon but temporary. Sexoperinatal interventions should be part of holistic perinatal health care in order to help couples maintain a positive intimate and sexual relationship.


Assuntos
Aleitamento Materno/psicologia , Período Periparto/psicologia , Período Pós-Parto/psicologia , Comportamento Sexual/psicologia , Parceiros Sexuais/psicologia , Feminino , Humanos , Gravidez
6.
Chem Commun (Camb) ; 52(3): 605-8, 2016 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-26553609

RESUMO

para-Hydrogen induced polarization is a technique of magnetic resonance hyperpolarization utilizing hydrogen's para-spin state for generating signal intensities at magnitudes far greater than state-of-the-art magnets. Platinum nanoparticle-catalysts with cysteine-capping are presented. The measured polarization is the highest reported to date in water, paving pathways for generating medical imaging contrast agents.

7.
Epigenetics ; 10(4): 342-51, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25800063

RESUMO

Leptin is an adipokine that acts in the central nervous system and regulates energy balance. Animal models and human observational studies have suggested that leptin surge in the perinatal period has a critical role in programming long-term risk of obesity. In utero exposure to maternal hyperglycemia has been associated with increased risk of obesity later in life. Epigenetic mechanisms are suspected to be involved in fetal programming of long term metabolic diseases. We investigated whether DNA methylation levels near LEP locus mediate the relation between maternal glycemia and neonatal leptin levels using the 2-step epigenetic Mendelian randomization approach. We used data and samples from up to 485 mother-child dyads from Gen3G, a large prospective population-based cohort. First, we built a genetic risk score to capture maternal glycemia based on 10 known glycemic genetic variants (GRS10) and showed it was an adequate instrumental variable (ß = 0.046 mmol/L of maternal fasting glucose per additional risk allele; SE = 0.007; P = 7.8 × 10(-11); N = 467). A higher GRS10 was associated with lower methylation levels at cg12083122 located near LEP (ß = -0.072 unit per additional risk allele; SE = 0.04; P = 0.05; N = 166). Direction and effect size of association between the instrumental variable GRS10 and methylation at cg12083122 were consistent with the negative association we observed using measured maternal glycemia. Lower DNA methylation levels at cg12083122 were associated with higher cord blood leptin levels (ß = -0.17 log of cord blood leptin per unit; SE = 0.07; P = 0.01; N = 170). Our study supports that maternal glycemia is part of causal pathways influencing offspring leptin epigenetic regulation.


Assuntos
Epigênese Genética , Regulação da Expressão Gênica , Hiperglicemia/genética , Leptina/genética , Troca Materno-Fetal , Adulto , Estudos de Coortes , Metilação de DNA , Feminino , Glucose/metabolismo , Humanos , Recém-Nascido , Masculino , Análise da Randomização Mendeliana/métodos , Gravidez
8.
Chem Sci ; 6(7): 4261-4266, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29218193

RESUMO

We report on the successful synthesis and hyperpolarization of N-unprotected α-amino acid ethyl propionate esters and extensively, on an alanine derivative hyperpolarized by PHIP (4.4 ± 1.0% 13C-polarization), meeting required levels for in vivo detection. Using water as solvent increases biocompatibility and the absence of N-protection is expected to maintain biological activity.

9.
J Dev Orig Health Dis ; 5(2): 132-41, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24847699

RESUMO

Placental lipoprotein lipase (LPL) is crucial for placental lipid transfer. Impaired LPL gene expression and activity were reported in pregnancies complicated by gestational diabetes mellitus (GDM) and intra-uterine growth restriction. We hypothesized that placental LPL DNA methylation is altered by maternal metabolic status and could contribute to fetal programming. The objective of this study was thus to assess whether placental LPL DNA methylation is associated with GDM and both maternal and newborn lipid profiles. Placenta biopsies were sampled at delivery from 126 women including 27 women with GDM diagnosed following a post 75 g-oral glucose tolerance test (OGTT) between weeks 24 and 28 of gestation. Placental LPL DNA methylation and expression levels were determined using bisulfite pyrosequencing and quantitative real-time PCR, respectively. DNA methylation levels within LPL proximal promoter region (CpG1) and intron 1 CpG island (CpGs 2 and 3) were lower in placenta of women with GDM. DNA methylation levels at LPL-CpG1 and CpG3 were also negatively correlated with maternal glucose (2-h post OGTT; r=-0.22; P=0.02) and HDL-cholesterol levels (third trimester of pregnancy; r=-0.20; p=0.03), respectively. Moreover, we report correlation between LPL-CpG2 DNA methylation and cord blood lipid profile. DNA methylation levels within intron 1 CpG island explained up to 26% (r⩽-0.51; P<0.001) of placental LPL mRNA expression variance. Overall, we showed that maternal metabolic profile is associated with placental LPL DNA methylation dysregulation. Our results suggest that site-specific LPL epipolymorphisms in the placenta are possibly functional and could potentially be involved in determining the future metabolic health of the newborn.


Assuntos
Metilação de DNA , Diabetes Gestacional/genética , Sangue Fetal/metabolismo , Lipídeos/sangue , Lipase Lipoproteica/genética , Placenta/metabolismo , Feminino , Humanos , Metabolismo dos Lipídeos , Lipase Lipoproteica/metabolismo , Gravidez , RNA Mensageiro/metabolismo
10.
Int J Genomics ; 2013: 609748, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23986905

RESUMO

The DUSP1 gene encodes a member of the dual-specificity phosphatase family previously identified as being differentially expressed in visceral adipose tissue (VAT) of severely obese men with versus without the metabolic syndrome. Objective. To test the association between DUSP1 polymorphisms, obesity-related metabolic complications, gene methylation, and expression levels in VAT. Methods. The DUSP1 locus and promoter region were sequenced in 25 individuals. SNPs were tested for association with obesity-related complications in a cohort of more than 1900 severely obese individuals. The impact of SNPs on methylation levels of 36 CpG sites and correlations between DNA methylation and gene expression levels in VAT were computed in a subset of 14 samples. Results. Heterozygotes for rs881150 had lower HDL-cholesterol levels (HDL-C; P = 0.01), and homozygotes for the minor allele of rs13184134 and rs7702178 had increased fasting glucose levels (P = 0.04 and 0.01, resp.). rs881150 was associated with methylation levels of CpG sites located ~1250 bp upstream the transcription start site. Methylation levels of 4 CpG sites were inversely correlated with DUSP1 gene expression. Conclusion. These results suggest that DUSP1 polymorphisms modulate plasma glucose and HDL-C levels in obese patients possibly through alterations of DNA methylation and gene expression levels.

11.
Atherosclerosis ; 228(2): 413-20, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23623643

RESUMO

BACKGROUND: Recent findings suggest that DNA methylation, a well-known epigenetic mechanism, is involved in high-density lipoprotein cholesterol (HDL-C) metabolism and increased cardiovascular disease risk. The aim of this study was thus to assess whether DNA methylation within key genes of lipoprotein metabolism is associated with blood lipid profile variability. METHODS AND RESULTS: Ninety-eight untreated familial hypercholesterolaemia patients (61 men and 37 women) were recruited for leucocyte DNA methylation analyses at the LDLR, CETP, LCAT and LPL gene promoter loci using bisulfite pyrosequencing. LPL DNA methylation was correlated with HDL-C (r = 0.22; p = 0.031) and HDL particle size (r = 0.47, p = 0.013). In both sex, CETP DNA methylation was negatively associated with low-density lipoprotein cholesterol levels (r < -0.32; p < 0.05). In men, CETP DNA methylation was associated with HDL-C (r = -0.36; p = 0.006), HDL-triglyceride levels (r = 0.59; p < 0.001) and HDL particle size (r = -0.44, p = 0.019). In visceral adipose tissue from 30 men with severe obesity, the associations between LPL DNA methylation, HDL-C (r = -0.40; p = 0.03) and LPL mRNA levels (r = -0.61, p < 0.001) were confirmed. CONCLUSION: CETP and LPL DNA methylation levels are associated with blood lipid profile, suggesting that further studies of epipolymorphisms should most certainly contribute to a better understanding of the molecular bases of dyslipidemia.


Assuntos
Proteínas de Transferência de Ésteres de Colesterol/genética , Metilação de DNA , Hiperlipoproteinemia Tipo II/sangue , Hiperlipoproteinemia Tipo II/genética , Lipídeos/sangue , Lipase Lipoproteica/genética , Regiões Promotoras Genéticas , Adulto , Distribuição de Qui-Quadrado , Feminino , Marcadores Genéticos , Predisposição Genética para Doença , Humanos , Hiperlipoproteinemia Tipo II/enzimologia , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Obesidade/sangue , Obesidade/enzimologia , Obesidade/genética , Fenótipo , Fosfatidilcolina-Esterol O-Aciltransferase/genética , Reação em Cadeia da Polimerase , Receptores de LDL/genética , Reprodutibilidade dos Testes , Fatores de Risco , Análise de Sequência de DNA/métodos , Fatores Sexuais
12.
Biotechnol Bioeng ; 109(7): 1844-54, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22252902

RESUMO

Shear stress is an important physical factor that regulates proliferation, migration, and morphogenesis. In particular, the homeostasis of blood vessels is dependent on shear stress. To mimic this process ex vivo, efforts have been made to seed scaffolds with vascular and other cell types in the presence of growth factors and under pulsatile flow conditions. However, the resulting bioreactors lack information on shear stress and flow distributions within the scaffold. Consequently, it is difficult to interpret the effects of shear stress on cell function. Such knowledge would enable researchers to improve upon cell culture protocols. Recent work has focused on optimizing the microstructural parameters of the scaffold to fine tune the shear stress. In this study, we have adopted a different approach whereby flows are redirected throughout the bioreactor along channels patterned in the porous scaffold to yield shear stress distributions that are optimized for uniformity centered on a target value. A topology optimization algorithm coupled to computational fluid dynamics simulations was devised to this end. The channel topology in the porous scaffold was varied using a combination of genetic algorithm and fuzzy logic. The method is validated by experiments using magnetic resonance imaging readouts of the flow field.


Assuntos
Reatores Biológicos , Estresse Mecânico , Alicerces Teciduais/química , Algoritmos , Simulação por Computador , Lógica Fuzzy , Hidrodinâmica , Modelos Químicos , Porosidade , Resistência ao Cisalhamento
13.
Hum Genet ; 131(1): 57-66, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21701784

RESUMO

A previous expression profiling of visceral adipose tissue (VAT) revealed that the immune response gene interferon-gamma-inducible protein 30 (IFI30) gene was 1.72-fold more highly expressed in non-diabetic severely obese men with the metabolic syndrome as compared to those without. Given the importance of low-grade inflammation in obesity-related metabolic complications, we hypothesized that variants in the IFI30 gene are associated with cardiovascular disease (CVD) risk factors. A detailed genetic investigation was performed at the IFI30 locus by sequencing its promoter, exons and intron-exon junction boundaries using DNA of 25 severely obese men. Among the 21 sequence-derived single-nucleotide polymorphisms (SNPs), 5 tagged SNPs (covering 100% of the common SNPs identified) were genotyped in two independent samples of severely obese patients (total n = 1,283). Using a multistage experimental design, chi-square analyses and logistic regressions were performed to compare genotype frequencies and compute odds-ratios (OR) for low and high CVD risk groups (dyslipidemia, hyperglycemia/diabetes and hypertension). A significant association was observed with the non-synonymous SNP rs11554159 (p.R76Q), where GA individuals showed lower risk (OR = 0.67; P = 0.0009) for hyperglycemia/diabetes as compared to homozygotes for the major allele (GG). No association was observed between rs11554159 and VAT IFI30 mRNA levels (P = 0.81), and the expression levels were not correlated with fasting plasma glucose levels (P = 0.31) in 112 non-diabetic severely obese women. The localization of rs11554159 near the active site of IFI30 suggests a functional effect of this SNP. This study showed a novel association between rs11554159 (p.R76Q) polymorphism at the IFI30 locus and the risk of hyperglycemia/diabetes in severely obese individuals.


Assuntos
Hiperglicemia/etiologia , Obesidade/complicações , Obesidade/genética , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/genética , Polimorfismo de Nucleotídeo Único/genética , Adulto , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/patologia , Estudos de Casos e Controles , Diabetes Mellitus/etiologia , Diabetes Mellitus/patologia , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Hiperglicemia/patologia , Desequilíbrio de Ligação , Masculino , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Risco
14.
Phys Rev Lett ; 104(7): 070801, 2010 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-20366868

RESUMO

The temperature dependence of the magnetic-resonance spectra of nitrogen-vacancy (NV-) ensembles in the range of 280-330 K was studied. Four samples prepared under different conditions were analyzed with NV- concentrations ranging from 10 ppb to 15 ppm. For all samples, the axial zero-field splitting (ZFS) parameter D was found to vary significantly with temperature, T, as dD/dT=-74.2(7) kHz/K. The transverse ZFS parameter E was nonzero (between 4 and 11 MHz) in all samples, and exhibited a temperature dependence of dE/(EdT)=-1.4(3)x10{-4} K-1. The results might be accounted for by considering local thermal expansion. The temperature dependence of the ZFS parameters presents a significant challenge for diamond magnetometers and may ultimately limit their bandwidth and sensitivity.

15.
Proc Natl Acad Sci U S A ; 105(7): 2271-3, 2008 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-18268323

RESUMO

We report the detection of nuclear magnetic resonance (NMR) using an anisotropic magnetoresistive (AMR) sensor. A "remote-detection" arrangement was used in which protons in flowing water were prepolarized in the field of a superconducting NMR magnet, adiabatically inverted, and subsequently detected with an AMR sensor situated downstream from the magnet and the adiabatic inverter. AMR sensing is well suited for NMR detection in microfluidic "lab-on-a-chip" applications because the sensors are small, typically on the order of 10 mum. An estimate of the sensitivity for an optimized system indicates that approximately 6 x 10(13) protons in a volume of 1,000 mum(3), prepolarized in a 10-kG magnetic field, can be detected with a signal-to-noise ratio of 3 in a 1-Hz bandwidth. This level of sensitivity is competitive with that demonstrated by microcoils in superconducting magnets and with the projected sensitivity of microfabricated atomic magnetometers.


Assuntos
Espectroscopia de Ressonância Magnética/instrumentação , Espectroscopia de Ressonância Magnética/métodos , Magnetismo , Anisotropia , Procedimentos Analíticos em Microchip , Sensibilidade e Especificidade , Termodinâmica
16.
Clin Genet ; 72(3): 224-9, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17718860

RESUMO

We have recently characterized the transcriptome of the omental adipose tissue of non-diabetic, obese men with and without the metabolic syndrome (MS). The cysteine-rich protein 61 (CYR61) is one of the most differentially expressed genes between the groups and has been selected for a detailed molecular investigation. Direct sequencing of complete CYR61 gene revealed five polymorphisms with minor allele frequency >5% in the promoter region (rs 3753794, rs 3753793 and rs 2297140), intron 1 (rs 2297141) and intron 2 (IVS 2+50). Chi-square test and logistic regression were applied to test for association between CYR61 polymorphisms and the individual MS components in a cohort of 697 obese individuals. In men and women, rs 3753794 and rs 3753793 (r2 = 0.77) were associated plasma HDL-cholesterol levels (p = 0.016 and p = 0.008). Carriers of the A allele for rs 3753794 were more likely to have high plasma HDL-cholesterol levels (1.50-fold; p = 0.016), as compared with G/G homozygotes and the A/A homozygotes for rs 3753793 were more likely to exhibit low plasma HDL-cholesterol levels (1.56-fold; p = 0.008), as compared with C/C homozygotes. Furthermore, an association between IVS 2+50 polymorphism and HDL-cholesterol was found in women and in men analyzed separately (p = 0.002 and p = 0.038, respectively). These results suggest that CYR61 is a promising candidate gene for lipoprotein/lipid perturbations.


Assuntos
HDL-Colesterol/sangue , Proteínas Imediatamente Precoces/genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Síndrome Metabólica/sangue , Síndrome Metabólica/genética , Polimorfismo de Nucleotídeo Único , Adulto , Proteína Rica em Cisteína 61 , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/sangue , Obesidade/genética
17.
Rev Sci Instrum ; 78(3): 035115, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17411225

RESUMO

Shimming systems are required to provide sufficient field homogeneity for high resolution nuclear magnetic resonance (NMR). In certain specialized applications, such as rotating-field NMR and mobile ex situ NMR, permanent magnet-based shimming systems can provide considerable advantages. We present a simple two-dimensional shimming method based on harmonic corrector rings which can provide arbitrary multipole order shimming corrections. Results demonstrate, for example, that quadrupolar order shimming improves the linewidth by up to an order of magnitude. An additional order of magnitude reduction is in principle achievable by utilizing this shimming method for z-gradient correction and higher order xy gradients.

18.
Clin Genet ; 71(3): 245-53, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17309647

RESUMO

Cardiovascular (CVD) risk factors are under the influence of environmental and genetic factors. Human upstream transcription factor 1 gene (USF1) encodes for a transcription factor, which modulates the expression of genes involved in lipid and carbohydrate metabolic pathways. The aim of this study was to test the hypothesis that USF1 gene variants are associated with CVD risk factors in the Quebec Family Study (QFS). USF1 has been sequenced in 20 QFS subjects with high plasma apolipoprotein B100 (APOB) levels (>1.14 g/l) and small, dense low-density lipoprotein (LDL) particles (> or =250.7 Angstroms and < or =255.9 Angstroms), as well as in five subjects with larger LDL particles. Ten variants were identified in non-coding regions of USF1. Two of these polymorphisms (intron 7 c.561-100 G>A, and exon 11 c.*187 C>T) as well as the c.-56 A>G polymorphism, were genotyped and analyzed in 760 subjects from QFS. Association studies showed that women with c.561-100 A/A and c.*187 T/T genotypes had more favorable adiposity indices (<0.04). In summary, significant associations between relatively common USF1 genetic variants and CVD risk factors were observed in French Canadians.


Assuntos
Doenças Cardiovasculares/genética , Predisposição Genética para Doença , Variação Genética , Fatores Estimuladores Upstream/genética , Adulto , Apolipoproteínas B/sangue , Índice de Massa Corporal , Doenças Cardiovasculares/epidemiologia , Estudos de Coortes , Feminino , Frequência do Gene , Genótipo , Humanos , Lipoproteínas LDL/sangue , Masculino , Pessoa de Meia-Idade , Fenótipo , Polimorfismo Genético , Quebeque , Fatores de Risco
19.
Int J Obes (Lond) ; 31(6): 891-9, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17299381

RESUMO

BACKGROUND: Several candidate genes have been associated with obesity, but very few studies have tested more than one gene simultaneously. METHODS: In this study, 15 polymorphisms in 10 candidate genes of obesity were tested for association with changes in adiposity measured over a period of 6-10 years in a maximum of 332 adult subjects with a wide range of adiposity (17.5or=40 years). RESULTS: In the whole sample, the variance in age-related adiposity changes explained by the candidate gene polymorphisms ranged from 3.1% (BMI, P<0.05) to 8.5% (fat mass (FM), P

Assuntos
Tecido Adiposo/fisiologia , Obesidade/genética , Polimorfismo Genético/genética , Adiposidade , Adulto , Índice de Massa Corporal , Feminino , Genótipo , Humanos , Masculino , Obesidade/epidemiologia , Estudos Prospectivos , Quebeque/epidemiologia , Dobras Cutâneas , Relação Cintura-Quadril
20.
Cardiovasc Intervent Radiol ; 29(2): 216-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16284702

RESUMO

PURPOSE: To evaluate the safety and efficacy of transjugular intrahepatic portosystemic shunt (TIPS) in the control of bleeding from ectopic varices. METHODS: From 1995 to 2004, 24 cirrhotic patients, bleeding from ectopic varices, mean age 54.5 years (range 15-76 years), were treated by TIPS. The etiology of cirrhosis was alcoholic in 13 patients and nonalcoholic in 11 patients. The location of the varices was duodenal (n = 5), stomal (n = 8), ileocolic (n = 6), anorectal (n = 3), umbilical (n = 1), and peritoneal (n = 1). RESULTS: TIPS controlled the bleeding in all patients and induced a decrease in the portacaval gradient from 19.7 +/- 5.4 to 6.4 +/- 3.1 mmHg. Postoperative complications included self-limited intra-abdominal bleeding (n = 2), self-limited hemobilia (n = 1), acute thrombosis of the shunt (n = 1), and bile leak treated by a covered stent (n = 1). Median follow-up was 592 days (range 28-2482 days). Rebleeding occurred in 6 patients. In 2 cases rebleeding was observed despite a post-TIPS portacaval gradient lower than 12 mmHg and was controlled by variceal embolization; 1 patient underwent surgical portacaval shunt and never rebled; in 3 patients rebleeding was related to TIPS stenosis and treated with shunt dilatation with addition of a new stent. The cumulative rate of rebleeding was 23% and 31% at 1 and 2 years, respectively. One- and 2-year survival rates were 80% and 76%, respectively. CONCLUSION: The present series demonstrates that bleeding from ectopic varices, a challenging clinical problem, can be managed safely by TIPS placement with low rebleeding and good survival rates.


Assuntos
Varizes Esofágicas e Gástricas/cirurgia , Hemorragia Gastrointestinal/cirurgia , Cirrose Hepática/complicações , Derivação Portossistêmica Transjugular Intra-Hepática , Adolescente , Adulto , Idoso , Varizes Esofágicas e Gástricas/etiologia , Feminino , Humanos , Cirrose Hepática/etiologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Recidiva , Stents , Taxa de Sobrevida , Resultado do Tratamento
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