167 research outputs found

    A study of endothelial function and circulating asymmetric dimethylarginine levels in people with Type 1 diabetes without macrovascular disease or microalbuminuria

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    <p>Abstract</p> <p>Background</p> <p>Asymmetric dimethylarginine (ADMA) is a competitive inhibitor of endothelial nitric oxide synthase (eNOS) that is associated with endothelial dysfunction, and is a risk marker for cardiovascular disease, a significant problem in Type 1 diabetes. The aim of the present study was to measure circulating ADMA, and define its association with endothelial dysfunction and endothelial markers in people with Type 1 diabetes with low likelihood of macrovascular disease.</p> <p>Methods</p> <p>Sixty-one young people with Type 1 diabetes without macrovascular disease or nephropathy and 62 healthy volunteers underwent brachial artery flow-mediated dilatation (FMD) and assay of plasma ADMA and adhesion molecules.</p> <p>Results</p> <p>Age, gender, BMI, lipid profile and renal function were similar in the two groups. People with Type 1 diabetes had impaired FMD compared to healthy controls (5.0 ± 0.4 vs 8.9 ± 0.4%; p < 0.001). Plasma ADMA levels were significantly lower in the people with diabetes compared to healthy controls (0.52 ± 0.12 vs 0.66 ± 0.20 μmol/l, p < 0.001). Plasma ICAM-1, E-selectin and PAI-1 levels were significantly higher in people with diabetes compared to healthy controls (median 201 (IQR 172–226) vs 180 (156–216) μg/l, p = 0.027; 44.2 (32.6–60.9) vs. 33.1 (22.4–51.0) μg/l; p = 0.003 and 70.8 (33.3–85.5) vs 46.3 (23.9–76.8) μg/l, p = 0.035). Plasma ADMA and VCAM-1 levels were positively correlated (r = 0.37, p = 0.003) in people with diabetes. There was no correlation between the plasma ADMA and FMD.</p> <p>Conclusion</p> <p>ADMA levels are not associated with endothelial dysfunction in young adults with Type 1 diabetes without microalbuminuria or known macrovascular disease. This suggests that the impaired endothelial function in these individuals is not a result of eNOS inhibition by ADMA.</p

    Eating patterns during pregnancy and postpartum and their association with diet quality and energy intake

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    This study investigates the relationship between meal-specific eating patterns during pregnancy and postpartum with maternal diet quality and energy intake. Participants in a prospective cohort study completed 24-h dietary recalls three times throughout both pregnancy and 1 year postpartum (n = 420). Linear regressions estimated the associations of eating frequency (number of daily main meals and eating occasions), meal and energy regularity (meal skipping and variation of daily energy intake), and intake timing patterns (distribution of energy intake throughout the day, derived using principal component analysis) with daily energy intake and diet quality (Healthy Eating Index-2015, calculated daily and overall, across both pregnancy and postpartum). Eating frequency was positively associated with energy intake and daily diet quality. Irregular meals were associated with lower energy intake in pregnancy but not postpartum and with lower pregnancy and postpartum diet quality. Energy irregularity was not associated with energy intake or diet quality. Higher postpartum diet quality was associated with a morning energy intake pattern (versus late morning/early afternoon or evening). Differences in these associations between pregnancy and postpartum suggest that efforts to support optimal energy intake and diet quality by modifying eating patterns may require specific strategies for pregnancy and postpartum

    First-principles calculations of the structural, electronic, vibrational and magnetic properties of C_{60} and C_{48}N_{12}: a comparative study

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    In this work, we perform first-principles calculations of the structural, electronic, vibrational and magnetic properties of a novel C48N12{\rm C}_{48}{\rm N}_{12} azafullerene. Full geometrical optimization shows that C48N12{\rm C}_{48}{\rm N}_{12} is characterized by several distinguishing features: only one nitrogen atom per pentagon, two nitrogen atoms preferentially sitting in one hexagon, S6{\rm S}_{6} symmetry, 6 unique nitrogen-carbon and 9 unique carbon-carbon bond lengths. The highest occupied molecular orbital of C48N12{\rm C}_{48}{\rm N}_{12} is a doubly degenerate level of aga_{g} symmetry and its lowest unoccupied molecular orbital is a nondegenerate level of aua_{u} symmetry. Vibrational frequency analysis predicts that C48N12{\rm C}_{48}{\rm N}_{12} has in total 116 vibrational modes: 58 infrared-active and 58 Raman-active modes. C48N12{\rm C}_{48}{\rm N}_{12} is also characterized by 8 13C^{13}{\rm C} and 2 15N^{15}{\rm N} NMR spectral signals. Compared to C60{\rm C}_{60}, C48N12{\rm C}_{48}{\rm N}_{12} shows an enhanced third-order optical nonlinearities which implies potential applications in optical limiting and photonics.Comment: a long version of our manuscript submitted to J.Chem.Phy

    Impact of the external school food environment on the associations of internal school food environment with high schoolers’ diet and BMI

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    OBJECTIVE: To examine associations of school food availability with student intake frequency and BMI, and whether the number of neighbourhood food outlets modifies these associations. DESIGN: Baseline assessment of a nationally representative cohort study of US 10th graders. Students reported intake frequency of fruits and vegetables (FV), snacks and soda. BMI was calculated from measured height and weight. Administrators of seventy-two high schools reported the frequency of school availability of FV, snacks and soda. The number of food outlets within 1 km and 5 km were linked with geocoded school addresses. Data were analysed using adjusted linear and logistic mixed models with multiple imputation for missing data. SETTING: US 2009-2010. PARTICIPANTS: Totally, 2263 US 10th graders from the Next Generation Health Study (NEXT). RESULTS: Greater school FV availability was positively associated with student FV intake. Food outlets within 5 km of schools (but not 1 km) attenuated the association of school FV availability with student intake; this was no longer significant at schools with > 58 food outlets within 5 km. School food availability was not associated with student BMI or student snack or soda intake. CONCLUSIONS: School food availability was associated with student intake of FV, but not with snacks, soda or BMI. Attenuation of the observed associations by the school neighbourhood food environment indicates a need to find ways to support healthy student eating behaviours in neighbourhoods with higher food outlet density

    Associations of ultra-processed food intake with maternal weight change and cardiometabolic health and infant growth

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    BACKGROUND: Excessive intake of ultra-processed foods, formulated from substances extracted from foods or derived from food constituents, may be a modifiable behavioral risk factor for adverse maternal and infant health outcomes. Prior work has predominately examined health correlates of maternal ultra-processed food intake in populations with substantially lower ultra-processed food intake compared to the US population. This longitudinal study investigated relations of ultra-processed food intake with maternal weight change and cardiometabolic health and infant growth in a US cohort. METHODS: Mothers in the Pregnancy Eating Attributes Study were enrolled at ≤12 weeks gestation and completed multiple 24-Hour Dietary Recalls within six visit windows through one-year postpartum (458 mothers enrolled, 321 retained at one-year postpartum). The NOVA (not an acronym) system categorized food and underlying ingredient codes based on processing level. Maternal anthropometrics were measured throughout pregnancy and postpartum, and infant anthropometrics were measured at birth and ages 2 months, 6 months, and 1 year. Maternal cardiometabolic markers were analyzed from blood samples obtained during the second and third trimesters. RESULTS: Holding covariates and total energy intake constant, a 1-SD greater percent energy intake from ultra-processed foods during pregnancy was associated with 31% higher odds of excessive gestational weight gain (p = .045, 95% CI [1.01, 1.70]), 0.68±0.29 mg/L higher c-reactive protein during pregnancy (p = .021, 95% CI [0.10, 1.26]), 6.7±3.4% greater gestational weight gain retained (p = .049, 95% CI [0.03, 13.30]), and 1.09±0.36 kg greater postpartum weight retention (p = .003, 95% CI [0.38, 1.80]). No other significant associations emerged. CONCLUSIONS: Ultra-processed food intake during pregnancy may be a modifiable behavioral risk factor for adverse maternal weight outcomes and inflammation. Randomized controlled trials are needed to test whether targeting ultra-processed food intake during pregnancy may support optimal maternal health. TRIAL REGISTRATION: Clinicaltrials.gov. Registration ID - NCT02217462. Date of registration - August 13, 2014

    Comparative effects of different dietary approaches on blood pressure in hypertensive and pre-hypertensive patients: A systematic review and network meta-analysis

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    Pairwise meta-analyses have shown beneficial effects of individual dietary approaches on blood pressure but their comparative effects have not been established. Objective: Therefore we performed a systematic review of different dietary intervention trials and estimated the aggregate blood pressure effects through network meta-analysis including hypertensive and pre-hypertensive patients. Design: PubMed, Cochrane CENTRAL, and Google Scholar were searched until June 2017. The inclusion criteria were defined as follows: i) Randomized trial with a dietary approach; ii) hypertensive and pre-hypertensive adult patients; and iii) minimum intervention period of 12 weeks. In order to determine the pooled effect of each intervention relative to each of the other intervention for both diastolic and systolic blood pressure (SBP and DBP), random effects network meta-analysis was performed. Results: A total of 67 trials comparing 13 dietary approaches (DASH, lowfat, moderate-carbohydrate, high-protein, low-carbohydrate, Mediterranean, Palaeolithic, vegetarian, low-GI/GL, low-sodium, Nordic, Tibetan, and control) enrolling 17,230 participants were included. In the network metaanalysis, the DASH, Mediterranean, low-carbohydrate, Palaeolithic, high-protein, low-glycaemic index, lowsodium, and low-fat dietary approaches were significantly more effective in reducing SBP (¡8.73 to ¡2.32 mmHg) and DBP (¡4.85 to ¡1.27 mmHg) compared to a control diet. According to the SUCRAs, the DASH diet was ranked the most effective dietary approach in reducing SBP (90%) and DBP (91%), followed by the Palaeolithic, and the low-carbohydrate diet (ranked 3rd for SBP) or the Mediterranean diet (ranked 3rd for DBP). For most comparisons, the credibility of evidence was rated very low to moderate, with the exception for the DASH vs. the low-fat dietary approach for which the quality of evidence was rated high. Conclusion: The present network meta-analysis suggests that the DASH dietary approach might be the most effective dietary measure toreduce blood pressure among hypertensive and pre-hypertensive patients based on high quality evidence

    Expression of cardiovascular-related microRNAs is altered in L-arginine:glycine amidinotransferase deficient mice

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    In humans and mice, L-arginine:glycine amidinotransferase (AGAT) and its metabolites homoarginine (hArg) and creatine have been linked to cardiovascular disease (CVD), specifically myocardial infarction (MI) and heart failure (HF). The underlying molecular and regulatory mechanisms, however, remain unclear. To identify potential pathways of cardiac AGAT metabolism, we sequenced microRNA (miRNA) in left ventricles of wild-type (wt) compared to AGAT-deficient (AGAT(-/-)) mice. Using literature search and validation by qPCR, we identified eight significantly regulated miRNAs in AGAT(-/-) mice linked to atherosclerosis, MI and HF: miR-30b, miR-31, miR-130a, miR-135a, miR-148a, miR-204, miR-298, and let-7i. Analysis of Gene Expression Omnibus (GEO) data confirmed deregulation of these miRNAs in mouse models of MI and HF. Quantification of miRNA expression by qPCR in AGAT(-/-) mice supplemented with creatine or hArg revealed that miR-30b, miR-31, miR-130a, miR-148a, and miR-204 were regulated by creatine, while miR-135a and miR-298 showed a trend of regulation by hArg. Finally, bioinformatics-based target prediction showed that numerous AGAT-dependent genes previously linked to CVD are likely to be regulated by the identified miRNAs. Taken together, AGAT deficiency and hArg/creatine supplementation are associated with cardiac miRNA expression which may influence cardiac (dys)function and CVD

    Literature-based discovery of diabetes- and ROS-related targets

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    Abstract Background Reactive oxygen species (ROS) are known mediators of cellular damage in multiple diseases including diabetic complications. Despite its importance, no comprehensive database is currently available for the genes associated with ROS. Methods We present ROS- and diabetes-related targets (genes/proteins) collected from the biomedical literature through a text mining technology. A web-based literature mining tool, SciMiner, was applied to 1,154 biomedical papers indexed with diabetes and ROS by PubMed to identify relevant targets. Over-represented targets in the ROS-diabetes literature were obtained through comparisons against randomly selected literature. The expression levels of nine genes, selected from the top ranked ROS-diabetes set, were measured in the dorsal root ganglia (DRG) of diabetic and non-diabetic DBA/2J mice in order to evaluate the biological relevance of literature-derived targets in the pathogenesis of diabetic neuropathy. Results SciMiner identified 1,026 ROS- and diabetes-related targets from the 1,154 biomedical papers (http://jdrf.neurology.med.umich.edu/ROSDiabetes/). Fifty-three targets were significantly over-represented in the ROS-diabetes literature compared to randomly selected literature. These over-represented targets included well-known members of the oxidative stress response including catalase, the NADPH oxidase family, and the superoxide dismutase family of proteins. Eight of the nine selected genes exhibited significant differential expression between diabetic and non-diabetic mice. For six genes, the direction of expression change in diabetes paralleled enhanced oxidative stress in the DRG. Conclusions Literature mining compiled ROS-diabetes related targets from the biomedical literature and led us to evaluate the biological relevance of selected targets in the pathogenesis of diabetic neuropathy.http://deepblue.lib.umich.edu/bitstream/2027.42/78315/1/1755-8794-3-49.xmlhttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/2/1755-8794-3-49-S7.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/3/1755-8794-3-49-S10.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/4/1755-8794-3-49-S8.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/5/1755-8794-3-49-S3.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/6/1755-8794-3-49-S1.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/7/1755-8794-3-49-S4.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/8/1755-8794-3-49-S2.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/9/1755-8794-3-49-S12.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/10/1755-8794-3-49-S11.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/11/1755-8794-3-49-S9.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/12/1755-8794-3-49-S5.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/13/1755-8794-3-49-S6.XLShttp://deepblue.lib.umich.edu/bitstream/2027.42/78315/14/1755-8794-3-49.pdfPeer Reviewe

    Developing a digital intervention for cancer survivors: an evidence-, theory- and person-based approach

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    This paper illustrates a rigorous approach to developing digital interventions using an evidence-, theory- and person-based approach. Intervention planning included a rapid scoping review which identified cancer survivors’ needs, including barriers and facilitators to intervention success. Review evidence (N=49 papers) informed the intervention’s Guiding Principles, theory-based behavioural analysis and logic model. The intervention was optimised based on feedback on a prototype intervention through interviews (N=96) with cancer survivors and focus groups with NHS staff and cancer charity workers (N=31). Interviews with cancer survivors highlighted barriers to engagement, such as concerns about physical activity worsening fatigue. Focus groups highlighted concerns about support appointment length and how to support distressed participants. Feedback informed intervention modifications, to maximise acceptability, feasibility and likelihood of behaviour change. Our systematic method for understanding user views enabled us to anticipate and address important barriers to engagement. This methodology may be useful to others developing digital interventions

    Nitric oxide metabolites: associations with cardiovascular biomarkers and clinical parameters in patients with HFpEF

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    AIMS: Heart failure with preserved ejection fraction (HFpEF) is one of the most rapidly growing cardiovascular health burden worldwide, but there is still a lack of understanding about the HFpEF pathophysiology. The nitric oxide (NO) signalling pathway has been identified as a potential key element. The aim of our study was to investigate markers of NO metabolism [ l-arginine ( l-Arg), homoarginine (hArg), and asymmetric and symmetric dimethylarginine (ADMA and SDMA)], additional biomarkers [N-terminal pro-B-type natriuretic peptide (NT-proBNP), endothelin-1 (ET-1), mid-regional pro-adrenomedullin (MR-proADM), copeptin, and high-sensitivity C-reactive protein (hsCRP)], and the endothelial function in an integrated approach focusing on associations with clinical characteristics in patients with HFpEF. METHODS AND RESULTS: Seventy-three patients, prospectively enrolled in the 'German HFpEF Registry', were analysed. Inclusion criteria were left ventricular ejection fraction (LVEF) ≥ 50%; New York Heart Association functional class ≥ II; elevated levels of NT-proBNP > 125 pg/mL; and at least one additional criterion for structural heart disease or diastolic dysfunction. All patients underwent transthoracic echocardiography, cardiopulmonary exercise testing, and pulse amplitude tonometry (EndoPAT™). Patients were categorized in two groups based on their retrospectively calculated HFA-PEFF score. Serum concentrations of l-Arg, hArg, ADMA, SDMA, NT-proBNP, ET-1, MR-proADM, copeptin, and hsCRP were determined. Patients had a median age of 74 years, 47% were female, and median LVEF was 57%. Fifty-two patients (71%) had an HFA-PEFF score ≥ 5 (definitive HFpEF), and 21 patients (29%) a score of 3 to 4 (risk for HFpEF). Overall biomarker concentrations were 126 ± 32 μmol/L for l-Arg, 1.67 ± 0.55 μmol/L for hArg, 0.74 (0.60;0.85) μmol/L for SDMA, and 0.61 ± 0.10 μmol/L for ADMA. The median reactive hyperaemia index (RHI) was 1.55 (1.38;1.87). SDMA correlated with NT-proBNP (r = 0.291; P = 0.013), ET-1 (r = 0.233; P = 0.047), and copeptin (r = 0.381; P = 0.001). ADMA correlated with ET-1 (r = 0.250; P = 0.033) and hsCRP (r = 0.303; P = 0.009). SDMA was associated with the left atrial volume index (β = 0.332; P = 0.004), also after adjustment for age, sex, and comorbidities. Biomarkers were non-associated with the RHI. A principal component analysis revealed two contrary clusters of biomarkers. CONCLUSIONS: Our findings suggest an impaired NO metabolism as one possible key pathogenic determinant in at least a subgroup of patients with HFpEF. We argue for further evaluation of NO-based therapies. Upcoming studies should clarify whether subgroups of HFpEF patients can take more benefit from therapies that are targeting NO metabolism and pathway
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