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Gadolinium (Gd) metal is of great interest in applications such as contrast-enhanced MRI and magnetic cooling. However, it is generally difficult to produce oxide-free and highly magnetic Gd nanoparticles due to the aggressively reactive nature of Gd with oxygen. Herein, we utilized a nanofabrication route and optimization of experimental conditions to produce highly magnetic airstable oxide-free Gd nanoparticles. The nanobowls displayed the highest saturation magnetization to date for Gd, reaching 226.4 emu/g at 2K. The crystalline composition of Gd is found to affect the observed magnetization values: the higher magnetization is observed for nanoparticles that have a lower content of the paramagnetic face-centered cubic (fcc) phase and a greater content of the ferromagnetic hexagonal close-packed (hcp) phase. The relative fcc content was found to depend on the deposition rate of the Gd metal during the nanofabrication process, thereby correlating with altered magnetization. [ABSTRACT FROM AUTHOR]

TheDUSP1 gene encodes a member of the dual-specificity phosphatase family previously identified as being differentially expressed in visceral adipose tissue (VAT) of severely obesemen with versus without the metabolic syndrome. Objective. To test the association betweenDUSP1 polymorphisms, obesity-relatedmetabolic complications, gene methylation, and expression levels inVAT. 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 lowerHDL-cholesterol levels (HDL-C; P= 0.01), and homozygotes for theminor 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 polymorphismsmodulate plasma glucose andHDL-C levels in obese patients possibly through alterations of DNA methylation and gene expression levels. [ABSTRACT FROM AUTHOR]

Growing evidence suggests that epigenetic profile changes occurring during fetal development in response to in utero environment variations could be one of the mechanisms involved in the early determinants of adult chronic diseases. In this study, we tested whether maternal glycemic status is associated with the adiponectin gene (ADIPOQ) DNA methylation profile in placenta tissue, in maternal circulating blood cells, and in cord blood cells. We found that lower DNA methylation levels in the promoter of ADIPOQ on the fetal side of the placenta were correlated with higher maternal glucose levels during the second trimester of pregnancy (2-h glucose after the oral glucose tolerance test; r(s) ≤ -0.21, P < 0.05). Lower DNA methylation levels on the maternal side of the placenta were associated with higher insulin resistance index (homeostasis model assessment of insulin resistance) during the second and third trimesters of pregnancy (r(s) ≤ -0.27, P < 0.05). Finally, lower DNA methylation levels were associated with higher maternal circulating adiponectin levels throughout pregnancy (r(s) ≤ -0.26, P < 0.05). In conclusion, the ADIPOQ DNA methylation profile was associated with maternal glucose status and with maternal circulating adiponectin concentration. Because adiponectin is suspected to have insulin-sensitizing proprieties, these epigenetic adaptations have the potential to induce sustained glucose metabolism changes in the mother and offspring later in life. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Existing literature indicates peer support is beneficial for people with mental illnesses and plays an important role in recovery. While many studies in the mental health field have focused on formalized peer support within the community, none have explored the experience of peer support among hospitalized patients. The purpose of the current study was to explore the perceptions and experiences of naturally occurring peer support among adult mental health inpatients. In-depth interviews were conducted with ten inpatients across four mental health units, two acute and two long-term. Interviews were transcribed verbatim and analyzed using a qualitative descriptive design. The data show that peer support among inpatients is extensive and beneficial, and occurs independently of staff involvement. The findings illustrate that peer support is a thoughtful process that involves observing, reflecting, taking action, and evaluating outcomes. Supportive actions include helping with activities of daily living, sharing material goods, providing information and advice, sharing a social life, and offering emotional support. This leads to various positive outcomes for providers and recipients of peer support, such as improved mental health outcomes and quality of life. Attempts to provide supportive interactions occur within a particular context, which can hinder or facilitate peer support. The new insights from this study could provide health professionals with an increased recognition of peer support and an appreciation for the unique role patients play in their own and in their peers’ recovery. These findings have important implications for establishing collaborative working partnerships with mental health inpatients. [ABSTRACT FROM AUTHOR]

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 (rs3753794, rs3753793 and rs2297140), intron 1 (rs2297141) and intron 2 (IVS2+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, rs3753794 and rs3753793 (r2 = 0.77) were associated plasma HDL-cholesterol levels (p = 0.016 and p = 0.008). Carriers of the A allele for rs3753794 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 rs3753793 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 IVS2+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. [ABSTRACT FROM AUTHOR]

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 (17.5

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 (≥250.7 Å and ≤255.9 Å), 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. [ABSTRACT FROM AUTHOR]

BACKGROUND:The phospholipid transfer protein (PLTP) may play a role in body fat regulation.OBJECTIVE:To investigate the association between PLTP genetic variants and obesity-related phenotypes.METHODS:Two intronic variants, one in intron 1 (c.−87G>A) and the other in intron 12 (c.1175+68T>G), were genotyped in 811 participants of the Québec Family Study. Nine obesity-related phenotypes were investigated, including body mass index (BMI), obesity (BMI≥30 kg/m2), and waist circumference, percentage of fat, fat mass and fat-free mass measured by hydrostatic weighing as well as total, visceral and subcutaneous abdominal adipose tissue areas assessed by computed tomography. Single markers and haplotypes were tested for associations in family-based designs using the FBAT program.RESULTS:The SNP located in intron 1 showed significant associations with obesity, BMI, waist circumference and fat-free mass (P<0.05). The low-frequency allele (A allele) was associated with higher trait values, suggesting that the transmission of this allele is associated with an increased risk of being obese. Significant associations were observed between haplotypes and obesity, waist circumference, percentage of fat and fat-free mass (P<0.05). The transmission of the AT haplotype (frequency=0.180) was positively associated with obesity-related phenotypes. After sequencing the promoter and the coding regions of the PLTP gene, we were unable to identify a mutation that could replicate these results.CONCLUSION:Intronic variants of the PLTP gene are significantly associated with obesity-related phenotypes. Considering the number and the relevance of candidate genes surrounding the PLTP locus and the absence of missense polymorphisms in the coding region, the associations could be mediated by a second gene allele in linkage disequilibrium with the marker locus.International Journal of Obesity (2005) 29, 1338–1345. doi:10.1038/sj.ijo.0803010; published online 7 June 2005 [ABSTRACT FROM AUTHOR]

The discovery linking the genes BRCA1&2 to familial breast cancer played an important role in the clinical practice of geneticists and physicians. The availability of genetic tests for BRCA gene mutations prompted cancer geneticists to give information about genetic risk and to assess many women with a personal or family history of breast or ovarian cancer to inform them of preventive measures. These consist mainly of breast self-examination, mammography screening, chemoprevention and prophylactic surgery (mastectomy, oophorectomy). This paper examines clinical practices related to hereditary breast cancer testing and introduces a number of results from a survey carried out, between 1996 and 1998, in three clinics located in Montreal (Quebec, Canada), Marseilles (France) and Manchester (Great Britain). Results show substantial differences in the way cancer geneticists deal with environmental risk factors, breast and ovarian cancer testing, and chemoprevention and prophylactic surgery. Differences across cities persist in the multivariate analysis, suggesting that attitudes towards preventive measures may be partially explained by cultural factors. Different dimensions of culture are discussed including the social representation of health and risk, the interpretation of scientific evidence and the role of innovation leadership. [ABSTRACT FROM AUTHOR]

Despite widespread use over the past 20 years, prenatal diagnosis (PND) remains a controversial technique because of the moral and organizational dilemmas that it raises in many countries. In order to assess attitudes to PND within the Canadian medical profession, a survey was carried out involving over 3000 physicians offering PND (general practitioners, obstetricians, pediatricians, and radiologists). Several scales were developed to measure (1) physicians' willingness to broaden access to PND, (2) acceptability of abortion when a fetal anomaly is diagnosed, and (3) physicians' directiveness in regard to abortion. This article discusses results concerning the attitudes and opinions of male and female physicians toward prenatal diagnosis, which differed on the three scales. Female physicians are more liberal than their male colleagues with regard to access to amniocentesis and selective abortion and have a less directive relationship with their patients. These tendencies are similar to those observed in prior studies. They are particularly marked for general practitioners and radiologists. Various explanatory hypotheses are examined. [ABSTRACT FROM AUTHOR]

We describe several numerical methods developed to analyze the behavior of spin polarized liquids in the presence of long-range magnetic dipolar interactions and external field gradients. Two of the methods use a discrete lattice of spins. In the first we calculate the magnetic field from the lattice of spins directly, either in the rotating frame, or in the lab frame. In the second method we include the dipolar fields from linear magnetization gradients analytically and calculate the dipolar fields from higher order gradients in Fourier space, where they are a local function of the magnetization. In the third method the magnetization is expanded in a Taylor series and the dipolar fields are calculated analytically for each term. The results of these calculations are compared to experimental data, in which we use two superconducting quantum interference device magnetometers adjacent to a spherical sample of hyperpolarized liquid 129Xe to detect the evolution of magnetization gradients. In particular, we observe an increase by a factor of 100 of the spin dephasing time in a longitudinal magnetic field gradient due to dipolar interactions of the spins. While each of the numerical techniques has certain limitations, they are generally in agreement with each other and with experimental data. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A correction to the article "Thymic stromal lymphopoietin: An immune cytokine gene associated with the metabolic syndrome and blood pressure in severe obesity" that was published in the 2012 issue is presented.

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. [ABSTRACT FROM AUTHOR]

Using intermolecular multiple-quantum coherence (iMQC) we report the first observation of Bragg-like diffraction via multiple distantly coupled nuclear spins. A compact quantum-mechanical formalism has been developed for analytically calculating iMQCs. The diffraction of iMQCs of various orders has been studied in a two-dimensional array structure. It indicates that phase cycling and flip angle selection are crucial for accurately measuring iMQC and the specific iMQCs measured in previous studies were likely contaminated by undesired coherences. We have also examined the capability and the current limitation of applying iMQCs for structural studies. The observation of iMQC diffraction introduces a new method for studying collective dynamics. [Copyright &y& Elsevier]

• 11B solid-state NMR studies on Sc 2 Ir 6-x Ni x B vs temperature and Ni substitution. • We present an atomic-level view of the lattice via quadrupolar interactions and paramagnetic effects upon Ir replacement. • NMR highlights short-range ordering and structural displacement that is not visible by XRD. • Nanoscale phase separation of ordered and disordered phases was studied by solid-state NMR. Intermetallic borides, such as the Sc 2 Ir 6- x Ni x B (x = 0–6) series, exhibit technologically relevant physicochemical properties, that are all associated to boron ordering. X-ray diffraction has not yet fully investigated the effect of Ir substitution by Ni on the boron arrangement of these borides, primarily due to its weak scattering factor. Herein we employ 11B-NMR to probe the boron ordering of Sc 2 Ir 6- x Ni x B series at atomic scale, overcoming limitations on low- Z materials. Across the Ni-substitution range, the spectral parameters and spin-lattice relaxation rates (T 1 − 1) were responsive to changes in crystal symmetry and valence charges. The spectral analysis and T 1 − 1 vs. x reveal that Ni substitution causes phase separation at the nanoscale between ordered and disordered borides. For x = 3, T 1 − 1 is T -independent, indicating a relaxation mechanism caused by paramagnetic centers whereas x = 5 follows a T2 -dependence that is consistent with band structure predictions of a reduction in the density of states, correlated with sharp features near the Fermi level. [Display omitted] [ABSTRACT FROM AUTHOR]

The presence of one-dimensional trigonal arrangements of chromium atoms (Cr 3 ) in the structure of TiCrIr 2 B 2 leads to a magnetic transition near ambient temperature. Herein we report an investigation of the nature of electronic and magnetic properties of TiCrIr 2 B 2 via ab initio calculations together with 11 B NMR Knight shift ( K ) and spin-lattice relaxation rate (1/ T 1 ) analysis. The presence of a characteristic rectangular powder pattern below 280 K, absence of a Korringa relation, strong enhancement of 1/ T 1 .T at low temperatures and weak temperature dependence of K indicate competition between antiferromagnetic and ferromagnetic spin fluctuations in the itinerant d -band electrons, in agreement with ab initio calculations. One-dimensional trigonal arrangements of magnetically active elements in intermetallic compounds, as is found in TiCrIr 2 B 2 , are quite rare and could lead to exotic phenomena such as spin-chirality and quantum criticality in low-dimensional frustrated lattices. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

While each atom species in PbSe corresponds to a single crystallographic site and transport measurements reveal a single carrier density, 207Pb NMR reveals a more complicated picture than previously thought comprising three discrete homogeneous carrier components, each associated with n- or p-type carrier fractions. The origins of these fractions are discussed in terms of electronic heterogeneity of the native semiconductor. The interaction mechanism between nuclear spins and lattice vibrations via fluctuating spin-rotation interaction, applicable to heavy spin-1/2 nuclei [Phys. Rev. B 74, 214420 (2006)], does not hold. Instead, a higher-order temperature dependence dominates the relaxation pathway. Shallow acceptor states and deep level defects in the midgap explain the complex temperature dependence of the direct band gap. [ABSTRACT FROM AUTHOR]

In recent years, diamond magnetometers based on the nitrogen-vacancy (NV) center have been of considerable interest for applications at the nanoscale. An interesting application which is well suited for NV centers is the study of nanoscale magnetic phenomena in superconducting materials. We employ NV centers to interrogate magnetic properties of a thin-layer yttrium barium copper oxide (YBCO) superconductor. Using fluorescence-microscopy methods and samples integrated with an NV sensor on a microchip, we measure the temperature of phase transition in the layer to be 70.0(2) K and the penetration field of vortices to be 46(4) G. We observe pinning of the vortices in the layer at 65 K and estimate their density after cooling the sample in a ∼10-G field to be 0.45(1) μm−2. These measurements are done with a 10-nm-thick NV layer, so that high spatial resolution may be enabled in the future. Based on these results, we anticipate that this magnetometer could be useful for imaging the structure and dynamics of vortices. As an outlook, we present a fabrication method for a superconductor chip designed for this purpose. [ABSTRACT FROM AUTHOR]

Abstract: 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. [Copyright &y& Elsevier]

We have previously shown that a missense mutation (p.P73T) located in the neuromedin-β gene, a satiety peptide, was associated with higher levels of disinhibition, susceptibility to hunger, and body weight gain over time. In this study we compare caloric compensation, eating behaviour traits, food intake and adiposity between premenopausal women with (T73T) and without (P73P) mutation. Subjects (N=153) were screened to find homozygous women (T73T) that were matched for age, BMI and use of oral contraceptives with 7 women (P73P) not carrying the mutation. Eating behaviour traits were assessed with the Three-Factors Eating Questionnaire and habitual dietary intakes with a 3-day dietary record. A randomized single-blind cross-over design was used to test the effect of p.P73T on caloric compensation. We measured appetite sensations and ad libitum dietary intake following two different energy preloads. We found no difference in eating behaviour traits, adiposity, appetite sensations, ad libitum dietary intake and caloric compensation. However, T73T women had lower habitual energy and carbohydrate intakes than P73P. Differences in carbohydrate intakes disappeared when expressed in percentage of energy. These results suggest that the neuromedin-β p.P73T mutation modulates energy intake without effects on macronutrient. A lack of power resulting from our difficulty to recruit enough T73T women precludes any definitive conclusion regarding the impact of this mutation on caloric compensation. [ABSTRACT FROM AUTHOR]

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 ~m. An estimate of the sensitivity for an optimized system indicates that ≈6 × 1013 protons in a volume of 1,000 µm³, 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. [ABSTRACT FROM AUTHOR]

Background: Abdominal visceral adiposity in early pregnancy has been associated with impaired glucose tolerance in later pregnancy. The "hypertriglyceridemic waist" phenotype (i.e., abdominal obesity in combination with hyper-triglyceridemia) is a clinical marker of visceral obesity. Our study aimed to assess the association between the hyper-triglyceridemic-waist phenotype in early pregnancy and glucose intolerance in later pregnancy.Methods: Plasma triglycerides and waist girth were measured at 11-14 weeks of gestation among 144 white pregnant women. Glycemia was measured following a 75-g oral glucose tolerance test performed at 24-28 weeks of gestation.Results: A waist girth greater than 85 cm in combination with a triglyceride level ≥ 1.7 mmol/L in the first trimester was associated with an increased risk of two-hour glucose ≥ 7.8 mmol/L following the 75-g oral glucose tolerance test (odds ratio [OR] 6.1, p = 0.002). This risk remained significant even after we controlled for maternal age, fasting glucose at first trimester and previous history of gestational diabetes (OR 4.7, p = 0.02).Interpretation: Measurement of waist girth in combination with measurement of triglyceride concentrations in the first trimester of pregnancy could improve early screening for gestational glucose intolerance. [ABSTRACT FROM AUTHOR]