783 research outputs found

    Enhanced Blood Pressure Acquisition

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    Blood pressure is considered a primary vital sign that is regularly monitored in a healthcare setting. Current blood pressure measurement equipment lacks reproducible measurements which leads to questionable accuracy. Therefore, there is a need for an accurate and reproducible blood pressure measurement device that can take remote measurements. This project will be designed in The University of Akron\u27s biomedical engineering capstone course. The goal of this senior design project is to design and fabricate a blood pressure measuring device that meets the customer requirements and engineering requirements identified by the team

    Spatially resolved optical absorption spectrometry and single crystal diffraction on metamict materials

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    A major goal in developing storage medium for radioactive waste is the identification of chemically suitable and durable material for storage in repositories (Lumpkin 2006). Radiation damage induces enhanced chemical diffusion and structural breakdown of the host materials, which can lead to contamination of the surrounding environment. During this project four different naturally occurring materials which are common carriers of thorium and uranium were examined : gadolinite, perrierite, allanite, and pyrochlore of which the first three are silicates and pyrochlore being an oxide. Their spectra and absorptions bands were examined to identify prominent features due to radiation damage. The goal of this study is to identify and characterize polyamorphisms metamict glasses. Further, we examine the hypothesis that pyrochlores do not amorphise but undergo a structural transition upon metamictization this part of the project will be conducted at the APS

    Role of highly branched, high molecular weight polymer structures in directing uniform polymer particle formation during nanoprecipitation

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    The new macromolecular architecture, hyperbranched polydendrons, are composed of a broad distribution of molecular weights and architectural variation; however, nanoprecipitation of these materials yields highly uniform, dendron-functional nanoparticles. By isolating different fractions of the diverse samples, the key role of the most highly branched structures in directing nucleation and growth has been explored and determined.</div

    Simple and effective exercise design for assessing in vivo mitochondrial function in clinical applications using (31)P magnetic resonance spectroscopy.

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    The growing recognition of diseases associated with dysfunction of mitochondria poses an urgent need for simple measures of mitochondrial function. Assessment of the kinetics of replenishment of the phosphocreatine pool after exercise using (31)P magnetic resonance spectroscopy can provide an in vivo measure of mitochondrial function; however, the wider application of this technique appears limited by complex or expensive MR-compatible exercise equipment and protocols not easily tolerated by frail participants or those with reduced mental capacity. Here we describe a novel in-scanner exercise method which is patient-focused, inexpensive, remarkably simple and highly portable. The device exploits an MR-compatible high-density material (BaSO4) to form a weight which is attached directly to the ankle, and a one-minute dynamic knee extension protocol produced highly reproducible measurements of post-exercise PCr recovery kinetics in both healthy subjects and patients. As sophisticated exercise equipment is unnecessary for this measurement, our extremely simple design provides an effective and easy-to-implement apparatus that is readily translatable across sites. Its design, being tailored to the needs of the patient, makes it particularly well suited to clinical applications, and we argue the potential of this method for investigating in vivo mitochondrial function in new cohorts of growing clinical interest.We are grateful to all the participants. This work was funded by the Clinical Research Infrastructure Grant. We thank the National Institute for Health Research (NIHR) Cambridge BioResource and S. Nutland, for facilitating the recruitment of the 24 BioResource volunteers. We thank the NIHR Cambridge Biomedical Research Centre for funding the BioResource and we also acknowledge research grants from Addenbrooke's Charitable Trust and the British Society for Pediatric Endocrinology and Diabetes. D.B.S. is supported by the Wellcome Trust [091551] and the U.K. National Institute for Health Research (NIHR) Cambridge Biomedical Research Centre. A.S. and the Siemens MAGNETOM 3T Verio scanner are funded by the NIHR via an award to the Cambridge NIHR/Wellcome Trust Clinical Research Facility. A.T. and D.B.D. are supported by the U.K. NIHR Cambridge Biomedical Research Centre. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.This is the final version of the article. It first appeared from Nature Publishing Group via http://dx.doi.org/10.1038/srep19057

    P-31 magnetization transfer measurements of P-i -> ATP flux in exercising human muscle

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    Fundamental criticisms have been made over the use of (31)P magnetic resonance spectroscopy (MRS) magnetization transfer estimates of inorganic phosphate (P(i))→ATP flux (V(Pi-ATP)) in human resting skeletal muscle for assessing mitochondrial function. Although the discrepancy in the magnitude of V(Pi-ATP) is now acknowledged, little is known about its metabolic determinants. Here we use a novel protocol to measure V(Pi-ATP) in human exercising muscle for the first time. Steady-state V(Pi-ATP) was measured at rest and over a range of exercise intensities and compared with suprabasal oxidative ATP synthesis rates estimated from the initial rates of postexercise phosphocreatine resynthesis (V(ATP)). We define a surplus P(i)→ATP flux as the difference between V(Pi-ATP) and V(ATP). The coupled reactions catalyzed by the glycolytic enzymes GAPDH and phosphoglycerate kinase (PGK) have been shown to catalyze measurable exchange between ATP and P(i) in some systems and have been suggested to be responsible for this surplus flux. Surplus V(Pi-ATP) did not change between rest and exercise, even though the concentrations of P(i) and ADP, which are substrates for GAPDH and PGK, respectively, increased as expected. However, involvement of these enzymes is suggested by correlations between absolute and surplus P(i)→ATP flux, both at rest and during exercise, and the intensity of the phosphomonoester peak in the (31)P NMR spectrum. This peak includes contributions from sugar phosphates in the glycolytic pathway, and changes in its intensity may indicate changes in downstream glycolytic intermediates, including 3-phosphoglycerate, which has been shown to influence the exchange between ATP and P(i) catalyzed by GAPDH and PGK

    Tracking of physical activity, fitness, body composition and diet from adolescence to young adulthood: The Young Hearts Project, Northern Ireland

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    BACKGROUND: The assumption that lifestyles formed early in life track into adulthood has been used to justify the targeting of health promotion programmes towards children and adolescents. The aim of the current study was to use data from the Northern Ireland Young Hearts Project to ascertain the extent of tracking, between adolescence and young adulthood, of physical activity, aerobic fitness, selected anthropometric variables, and diet. METHODS: Males (n 245) and females (n 231) were assessed at age 15 y, and again in young adulthood [mean (SD) age 22 (1.6) y]. At both timepoints, height, weight and skinfold thicknesses were measured, and physical activity and diet were assessed by questionnaire and diet history method respectively. At 15y, fitness was assessed using the 20 metre shuttle run, while at young adulthood, the PWC170 cycle ergometer test was used. For each measurement made at 15y, subjects were ranked into 'low' (L1; lowest 25%), 'medium' (M1; middle 50%) or 'high' (H1; highest 25%) categories. At young adulthood, similar categories (L2, M2, H2) were created. The extent of tracking of each variable over time was calculated using 3 × 3 matrices constructed using these two sets of categories, and summarised using kappa (κ) statistics. RESULTS: Tracking of diet and fitness was poor (κ ≤ 0.20) in both sexes, indicating substantial drift of subjects between the low, medium and high categories over time. The tracking of physical activity in males was fair (κ 0.202), but was poor in females (κ 0.021). In contrast, anthropometric variables such as weight, body mass index and sum of skinfolds tracked more strongly in females (κ 0.540, κ 0.307, κ 0.357 respectively) than in males (κ 0.337, κ 0.199, κ 0.216 respectively). CONCLUSIONS: The poor tracking of fitness and diet in both sexes, and physical activity in females, suggests that these aspects of adolescent lifestyle are unlikely to be predictive of behaviours in young adulthood. In contrast, the fair to moderate tracking of anthropometric variables, particularly in females, suggests that attempts to reduce the ever increasing incidence of overweight and obesity in adults, should probably begin in earlier life

    More Rapid Increase in BMI from Age 5–15 is Associated with Elevated Weight Status at Age 24 among Non-Hispanic White Females

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    Background: A rapidly increasing BMI trajectory throughout childhood is associated with negative health outcomes in adulthood such as obesity, cardiovascular disease, and diabetes. The purpose of the current study was to assess whether BMI trajectories from age 5–15 predicted changes in weight and BMI from adolescence to adulthood, and dieting-related behaviors in young adulthood. Methods: Non-Hispanic White female participants from Early Dieting in Girls (n=182), a longitudinal cohort study, were followed from age 5 to 15 and completed a follow-up survey at age 24. Participants were classified by age 5–15 BMI trajectory groups: UPC, accelerated weight gain from age 5–9; DDPC, accelerated weight gain from 5 to 9 followed by a decrease; 60PT, weight tracked along 60th percentile; 50PT, weight tracked along 50th percentile. Data at age 24 included self-reported weight, height, dietary restraint, disinhibition, and dieting. Results: Majority of participants (80.8%) completed the follow-up survey; of these participants, 60% in UPC group had obesity at age 24, compared to\u3c10% in the other 3 groups. Participants in the UPC group had greater increases in BMI since age 15, compared to the 50PT group, and trend-level greater weight increases than those in the DDPC and 60PT groups. Dietary restraint, but not disinhibition, differed across the groups. Conclusions: Children with accelerated weight gain continued to have the greatest weight gain from adolescence to adulthood and the highest prevalence of obesity in adulthood

    Accumulation of saturated intramyocellular lipid is associated with insulin resistance.

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    Intramyocellular lipid (IMCL) accumulation has been linked to both insulin-resistant and insulin-sensitive (athletes) states. Biochemical analysis of intramuscular triglyceride composition is confounded by extramyocellular triglycerides in biopsy samples, and hence the specific composition of IMCLs is unknown in these states. 1H magnetic resonance spectroscopy (MRS) can be used to overcome this problem. Thus, we used a recently validated 1H MRS method to compare the compositional saturation index (CH2:CH3) and concentration independent of the composition (CH3) of IMCLs in the soleus and tibialis anterior muscles of 16 female insulin-resistant lipodystrophic subjects with that of age- and gender-matched athletes (n = 14) and healthy controls (n = 41). The IMCL CH2:CH3 ratio was significantly higher in both muscles of the lipodystrophic subjects compared with controls but was similar in athletes and controls. IMCL CH2:CH3 was dependent on the IMCL concentration in the controls and, after adjusting the compositional index for quantity (CH2:CH3adj), could distinguish lipodystrophics from athletes. This CH2:CH3adj marker had a stronger relationship with insulin resistance than IMCL concentration alone and was inversely related to VO2max The association of insulin resistance with the accumulation of saturated IMCLs is consistent with a potential pathogenic role for saturated fat and the reported benefits of exercise and diet in insulin-resistant states
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