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Sample records for elevated glucose concentrations

  1. Elevated D-glucose concentrations modulate TGF-beta 1 synthesis by human cultured renal proximal tubular cells. The permissive role of platelet-derived growth factor.

    PubMed Central

    Phillips, A. O.; Steadman, R.; Topley, N.; Williams, J. D.

    1995-01-01

    Interstitial fibrosis is a marker of progression of renal impairment in diabetic nephropathy. Transforming growth factor (TGF)-beta 1 is one of a group of pro-fibrotic cytokines and growth factors that have been associated with the development of interstitial fibrosis. We have examined the modulating influence of glucose on the production of TGF-beta 1 by cultured human proximal tubular cells. Incubation of growth-arrested human proximal tubular cells (HPTC) (72 hours in serum free medium) in 25 mmol/L D-glucose resulted in increased expression of TGF-beta 1 mRNA (as assessed by reverse transcription polymerase chain reaction). This was apparent after 6 hours and increased up to 120 hours exposure. TGF-beta 1 secretion, however, as measured by specific enzyme-linked immunoassay, was unaffected by exposure to 25 mmol/L D-glucose. Sequential stimulation of HPTC, first with 25 mmol/L D-glucose for 48 hours and then with platelet-derived growth factor (PDGF) isoforms, resulted in a dose-dependent secretion of TGF-beta 1. Pre-exposure to 5 mmol/L D-glucose or 25 mmol/L L-glucose did not prime for TGF-beta 1 release. At 50 ng/ml PDGF this effect was greatest for the AA isoform (AA 31.4 +/- 7.1, AB 20.98 +/- 8.9, BB 7.8 +/- 2.2, P < 0.05 for all versus control, n = 3, mean +/- SEM ng/10(6) cells/24 hours). These effects were blocked by the addition of antibody to the PDGF alpha-receptor. TGF-beta 1 secretion was inhibited in a dose-dependent manner by pretreatment with cyclohexamide, but was not affected by pretreatment with actinomycin D. Stimulation of HPTC with a single dose of PDGF induced TGF-beta 1 mRNA; however, only after application of a second dose of PDGF (after TGF-beta 1 mRNA induction) did TGF-beta 1 protein secretion occur. We also demonstrated that PDGF stimulation of HPTC induced an inherently more stable TGF-beta 1 mRNA transcript. These findings demonstrate that elevated D-glucose concentration alone is insufficient to lead to increased TGF-beta 1

  2. Optical monitoring of glucose concentration

    NASA Astrophysics Data System (ADS)

    Ross, I. N.; Mbanu, A.

    1985-02-01

    A device for the monitoring of blood glucose levels is investigated. It measures the sugar concentration using the effect of the glucose on the optical refractive index. Light is transmitted along an optical fibre, and, as most of the internal rays are incident at the fibre surface at an angle less than the critical angle, the refractive index of the surrounding liquid can be calculated. The device can measure glucose concentrations with a sensitivity of better than 0.1%.

  3. Rice (Oryza sativa japonica) Albumin Suppresses the Elevation of Blood Glucose and Plasma Insulin Levels after Oral Glucose Loading.

    PubMed

    Ina, Shigenobu; Ninomiya, Kazumi; Mogi, Takashi; Hase, Ayumu; Ando, Toshiki; Matsukaze, Narumi; Ogihara, Jun; Akao, Makoto; Kumagai, Hitoshi; Kumagai, Hitomi

    2016-06-22

    The suppressive effect of rice albumin (RA) of 16 kDa on elevation of blood glucose level after oral loading of starch or glucose and its possible mechanism were examined. RA suppressed the increase in blood glucose levels in both the oral starch tolerance test and the oral glucose tolerance test. The blood glucose concentrations 15 min after the oral administration of starch were 144 ± 6 mg/dL for control group and 127 ± 4 mg/dL for RA 200 mg/kg BW group, while those after the oral administration of glucose were 157 ± 7 mg/dL for control group and 137 ± 4 mg/dL for RA 200 mg/kg BW group. However, in the intraperitoneal glucose tolerance test, no significant differences in blood glucose level were observed between RA and the control groups, indicating that RA suppresses the glucose absorption from the small intestine. However, RA did not inhibit the activity of mammalian α-amylase. RA was hydrolyzed to an indigestible high-molecular-weight peptide (HMP) of 14 kDa and low-molecular-weight peptides by pepsin and pancreatin. Furthermore, RA suppressed the glucose diffusion rate through a semipermeable membrane like dietary fibers in vitro. Therefore, the indigestible HMP may adsorb glucose and suppress its absorption from the small intestine. PMID:27228466

  4. Nonlinear optical measurements of glucose concentration

    NASA Astrophysics Data System (ADS)

    Yakovlev, V. V.

    2008-02-01

    Diabetes mellitus is a metabolic disease that currently affects about 7% of the US population, or roughly about 20 million people. Effectively controlling diabetes requires regular measurements of the blood sugar levels to ensure the one time insulin injection when the concentration of glucose reaches a critical level. In this report, nonlinear Raman microspectroscopy is demonstrated to be a promising new way of continuous and noninvasive way of measuring the glucose concentration.

  5. Glucose concentration in parotid saliva after glucose/food intake in individuals with glucose intolerance and diabetes mellitus.

    PubMed

    Borg Andersson, A; Birkhed, D; Berntorp, K; Lindgärde, F; Matsson, L

    1998-10-01

    The concentration of glucose in parotid saliva was measured after glucose/food intake in two separate studies (A and B). In Study A, 10 subjects with impaired glucose tolerance (IGT), 10 subjects with newly diagnosed Type 2 diabetes and 12 healthy controls were included. Study B comprised 15 subjects with Type 1 or Type 2 diabetes on insulin treatment, nine subjects with Type 2 diabetes on treatment with oral antidiabetic drugs and 12 healthy controls. After a 10-h overnight fast, the participants in Study A were given a 75 g oral glucose load, while those in Study B received a standardized breakfast. Citric acid-stimulated parotid saliva was collected up to two hours after the intake. Capillary blood and gingival exudate samples were also taken. On the basis of AUC values (area under the curve over baseline), the glucose concentration in parotid saliva increased significantly in individuals with IGT and Type 2 diabetes compared with controls in Study A and in diabetic patients on treatment with insulin and oral antidiabetic drugs compared with controls in Study B. No effect by the glucose/food intake on the glucose concentration in gingival exudate could be demonstrated in any of the studies. The correlation coefficient between the AUC values of glucose in saliva and blood, when all three groups were combined, was 0.38 in Study A and 0.52 in Study B. It is concluded that the concentration of glucose in parotid saliva is elevated at least 2 h after glucose/food intake in individuals with both IGT and manifest diabetes mellitus. PMID:9786322

  6. Disproportionately elevated proinsulinemia is observed at modestly elevated glucose levels within the normoglycemic range.

    PubMed

    Lorenzo, Carlos; Hanley, Anthony J; Rewers, Marian J; Haffner, Steven M

    2014-08-01

    We aimed to evaluate disproportional proinsulinemia in the pre-diabetic state by analyzing the cross-sectional differences between proinsulin (PI) ratios across the entire range of fasting and 2-h plasma glucose. The study sample was 1,016 participants in the insulin resistance atherosclerosis study, who had no previous diagnosis of diabetes. Insulin sensitivity index (SI) and acute insulin response (AIR) were measured by the frequently sampled intravenous glucose tolerance test. Fasting intact and split PI-to-insulin ratios (PI/I, SPI/I), intact and split PI-to-C-peptide ratios (PI/C-pep, SPI/C-pep), and SI-adjusted AIR were assessed as a function of fasting and 2-h glucose levels. SI-adjusted AIR was decreased (fasting glucose 96-98 mg/dl; 2-h glucose 120-131 mg/dl) and SPI/C-pep increased at modestly elevated fasting glucose and 2-h glucose within the normal glucose tolerance range (fasting glucose 96-98 mg/dl; 2-h glucose 132-142 mg/dl). PI/I was not increased until plasma glucose values were in the diabetic range of fasting glucose (>126 mg/dl) or the impaired glucose tolerance range of 2-h glucose (143-156 mg/dl). SPI/I and PI/C-pep as a function of fasting and 2-h glucose were situated between the curves for SPI/C-pep and PI/I. In conclusion, inappropriate amounts of PI and conversion intermediaries are demonstrated at modestly elevated glucose levels within the normoglycemic range. Ratios that use SPI in the numerator or C-pep in the denominator (and especially SPI/C-pep) are more sensitive to early glycemic excursions than PI/I. Disordered processing of PI may accompany derangements in early insulin secretory response. PMID:24532116

  7. Plasma Efavirenz Concentrations Are Associated With Lipid and Glucose Concentrations

    PubMed Central

    Sinxadi, Phumla Zuleika; McIlleron, Helen Margaret; Dave, Joel Alex; Smith, Peter John; Levitt, Naomi Sharlene; Haas, David William; Maartens, Gary

    2016-01-01

    Abstract Efavirenz-based antiretroviral therapy (ART) has been associated with dyslipidemia and dysglycemia, risk factors for cardiovascular disease. However, the pathogenesis is not well understood. We characterized relationships between plasma efavirenz concentrations and lipid and glucose concentrations in HIV-infected South Africans. Participants on efavirenz-based ART were enrolled into a cross-sectional study. The oral glucose tolerance test was performed after an overnight fast, and plasma drawn for mid-dosing interval efavirenz, fasting total cholesterol, low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol, and triglycerides concentrations. Among 106 participants (77 women), median age was 38 years, median CD4 + T-cell count was 322 cells/μL, median duration on ART was 18 months, and median (interquartile range) efavirenz concentration was 2.23 (1.66 to 4.10) μg/mL. On multivariable analyses (adjusting for age, sex, body mass index, and ART duration) doubling of efavirenz concentrations resulted in mean changes in mmol/L (95%CI) of: total cholesterol (0.40 [0.22 to 0.59]), LDL cholesterol (0.19 [0.04 to 0.30]), HDL cholesterol (0.14 [0.07 to 0.20]), triglycerides (0.17 [0.03 to 0.33]), fasting glucose (0.18 [0.03 to 0.33]), and 2-h glucose concentrations (0.33 [0.08 to 0.60]). Among 57 participants with CYP2B6 genotype data, associations between slow metabolizer genotypes and metabolic profiles were generally consistent with those for measured efavirenz concentrations. Higher plasma efavirenz concentrations are associated with higher plasma lipid and glucose concentrations. This may have implications for long-term cardiovascular complications of efavirenz-based ART, particularly among populations with high prevalence of CYP2B6 slow metabolizer genotypes. PMID:26765416

  8. Plasma Efavirenz Concentrations Are Associated With Lipid and Glucose Concentrations.

    PubMed

    Sinxadi, Phumla Zuleika; McIlleron, Helen Margaret; Dave, Joel Alex; Smith, Peter John; Levitt, Naomi Sharlene; Haas, David William; Maartens, Gary

    2016-01-01

    Efavirenz-based antiretroviral therapy (ART) has been associated with dyslipidemia and dysglycemia, risk factors for cardiovascular disease. However, the pathogenesis is not well understood. We characterized relationships between plasma efavirenz concentrations and lipid and glucose concentrations in HIV-infected South Africans.Participants on efavirenz-based ART were enrolled into a cross-sectional study. The oral glucose tolerance test was performed after an overnight fast, and plasma drawn for mid-dosing interval efavirenz, fasting total cholesterol, low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol, and triglycerides concentrations.Among 106 participants (77 women), median age was 38 years, median CD4 + T-cell count was 322 cells/μL, median duration on ART was 18 months, and median (interquartile range) efavirenz concentration was 2.23 (1.66 to 4.10) μg/mL. On multivariable analyses (adjusting for age, sex, body mass index, and ART duration) doubling of efavirenz concentrations resulted in mean changes in mmol/L (95%CI) of: total cholesterol (0.40 [0.22 to 0.59]), LDL cholesterol (0.19 [0.04 to 0.30]), HDL cholesterol (0.14 [0.07 to 0.20]), triglycerides (0.17 [0.03 to 0.33]), fasting glucose (0.18 [0.03 to 0.33]), and 2-h glucose concentrations (0.33 [0.08 to 0.60]). Among 57 participants with CYP2B6 genotype data, associations between slow metabolizer genotypes and metabolic profiles were generally consistent with those for measured efavirenz concentrations.Higher plasma efavirenz concentrations are associated with higher plasma lipid and glucose concentrations. This may have implications for long-term cardiovascular complications of efavirenz-based ART, particularly among populations with high prevalence of CYP2B6 slow metabolizer genotypes. PMID:26765416

  9. Antiproliferative effect of elevated glucose in human microvascular endothelial cells

    NASA Technical Reports Server (NTRS)

    Kamal, K.; Du, W.; Mills, I.; Sumpio, B. E.

    1998-01-01

    Diabetic microangiopathy has been implicated as a fundamental feature of the pathological complications of diabetes including retinopathy, neuropathy, and diabetic foot ulceration. However, previous studies devoted to examining the deleterious effects of elevated glucose on the endothelium have been performed largely in primary cultured cells of macrovessel origin. Difficulty in the harvesting and maintenance of microvascular endothelial cells in culture have hindered the study of this relevant population. Therefore, the objective of this study was to characterize the effect of elevated glucose on the proliferation and involved signaling pathways of an immortalized human dermal microvascular endothelial cell line (HMEC-1) that possess similar characteristics to their in vivo counterparts. Human dermal microvascular endothelial cells (HMEC-1) were grown in the presence of normal (5 mM) or high D-glucose (20 mM) for 14 days. The proliferative response of HMEC-1 was compared under these conditions as well as the cAMP and PKC pathways by in vitro assays. Elevated glucose significantly inhibited (P < 0.05) HMEC-1 proliferation after 7, 10, and 14 days. This effect was not mimicked by 20 mM mannitol. The antiproliferative effect was more pronounced with longer exposure (1-14 days) to elevated glucose and was irreversible 4 days after a 10-day exposure. The antiproliferative effect was partially reversed in the presence of a PKA inhibitor, Rp-cAMP (10-50 microM), and/or a PKC inhibitor, Calphostin C (10 nM). HMEC-1 exposed to elevated glucose (20 mM) for 14 days caused an increase in cyclic AMP accumulation, PKA, and PKC activity but was not associated with the activation of downstream events such as CRE and AP-1 binding activity. These data support the hypothesis that HMEC-1 is a suitable model to study the deleterious effects of elevated glucose on microvascular endothelial cells. Continued studies with HMEC-1 may prove advantageous in delineation of the molecular

  10. Determination of Glucose Concentration in Yeast Culture Medium

    NASA Astrophysics Data System (ADS)

    Hara, Seiichi; Kishimoto, Tomokazu; Muraji, Masafumi; Tsujimoto, Hiroaki; Azuma, Masayuki; Ooshima, Hiroshi

    The present paper describes a sensor for measuring the glucose concentration of yeast culture medium. The sensor determines glucose concentration by measuring the yield of hydrogen peroxide produced by glucose oxidase, which is monitored as luminescence using photomultiplier. The present sensor is able to measure low glucose concentration in media in which yeast cells keep respiration state. We herein describe the system and the characteristics of the glucose sensor.

  11. Elevated glucose levels in early puerperium, and association with high cortisol levels during parturition.

    PubMed

    Risberg, Anitha; Sjöquist, Mats; Wedenberg, Kaj; Larsson, Anders

    2016-07-01

    Background Gestational diabetes is one of the commonest metabolic problems associated with pregnancy and an accurate diagnosis is critical for the care. Research has shown that pregnant women have high levels of cortisol during the last stage of parturition. As cortisol is a diabetogenic hormone causing increased glucose levels, we wanted to study the association between cortisol and glucose levels during parturition. Materials and methods Glucose and cortisol were analyzed during parturition in 50 females divided according to slow (n = 11) and normal labors (n = 39). Blood samples were analyzed three times during the parturition and four times in the first day after delivery. Glucose levels were also measured once in each trimester. Results In the normal group, the glucose concentration increased from 6.2 (IQR 5.6-8.0) mmol/L in the latency phase to 11.6 (10.0-13.3) mmol/L at aftercare (p < 0.05). After parturition the glucose concentrations decreased gradually. There were significant Spearman rank correlations between glucose and cortisol values. Conclusions The changes associated with birth cause significant elevations of cortisol and glucose around parturition. PMID:26985979

  12. Single Cell "Glucose Nanosensor" Verifies Elevated Glucose Levels in Individual Cancer Cells.

    PubMed

    Nascimento, Raphael A S; Özel, Rıfat Emrah; Mak, Wai Han; Mulato, Marcelo; Singaram, Bakthan; Pourmand, Nader

    2016-02-10

    Because the transition from oxidative phosphorylation to anaerobic glycolytic metabolism is a hallmark of cancer progression, approaches to identify single living cancer cells by their unique glucose metabolic signature would be useful. Here, we present nanopipettes specifically developed to measure glucose levels in single cells with temporal and spatial resolution, and we use this technology to verify the hypothesis that individual cancer cells can indeed display higher intracellular glucose levels. The nanopipettes were functionalized as glucose nanosensors by immobilizing glucose oxidase (GOx) covalently to the tip so that the interaction of glucose with GOx resulted in a catalytic oxidation of β-d-glucose to d-gluconic acid, which was measured as a change in impedance due to drop in pH of the medium at the nanopipette tip. Calibration studies showed a direct relationship between impedance changes at the tip and glucose concentration in solution. The glucose nanosensor quantified single cell intracellular glucose levels in human fibroblasts and the metastatic breast cancer lines MDA-MB-231 and MCF7 and revealed that the cancer cells expressed reproducible and reliable increases in glucose levels compared to the nonmalignant cells. Nanopipettes allow repeated sampling of the same cell, as cells remain viable during and after measurements. Therefore, nanopipette-based glucose sensors provide an approach to compare changes in glucose levels with changes in proliferative or metastatic state. The platform has great promise for mechanistic investigations, as a diagnostic tool to distinguish cancer cells from nonmalignant cells in heterogeneous tissue biopsies, as well as a tool for monitoring cancer progression in situ. PMID:26752097

  13. Elevated concentrations of actinides in mono lake.

    PubMed

    Anderson, R F; Bacon, M P; Brewer, P G

    1982-04-30

    Tetravalent thorium, pentavalent protactinium, hexavalent uranium, and plutonium (oxidation state uncertain) are present in much higher concentrations in Mono Lake, a saline, alkaline lake in eastern central California, than in seawater. Low ratios of actinium to protactinium and of americium to plutonium indicate that the concentrations of trivalent actinides are not similarly enhanced. The elevated concentrations of the ordinarily very insoluble actinides are maintained in solution by natural ligands, which inhibit their chemical removal from the water column, rather than by an unusually large rate of supply. PMID:17735740

  14. Elevated concentrations of actinides in Mono Lake

    SciTech Connect

    Anderson, R.F.; Bacon, M.P.; Brewer, P.G.

    1982-04-30

    Tetravalent thorium, pentavalent protactinium, hexavalent uranium, and plutonium (oxidation state uncertain) are present in much higher concentrations in Mono Lake, a saline, alkaline lake in eastern central California, than in seawater. Low ratios of actinium to protactinium and of americium to plutonium indicate that the concentrations of trivalent actinides are not similarly enhanced. The elevated concentrations of the ordinarily very insoluble actinides are maintained in solution by natural ligands, which inhibit their chemical removal from the water column, rather than by an unusually large rate of supply.

  15. Acute elevation of endogenous prolactin does not influence glucose homeostasis in healthy men.

    PubMed

    Vigas, M; Klimes, I; Jurcovicová, J; Jezová, D

    1993-01-01

    The diabetogenic effect of prolactin observed in patients with pathological hyperprolactinaemia was verified in healthy subjects. Plasma prolactin elevation was induced by administration of a dopamine antagonist drug domperidone (Motilium 10 mg orally, 9 subjects) and 2 h later the oral glucose tolerance test was performed. The influence of dopamine receptor stimulation on glucose homeostasis was tested by dopamine infusion (0.3 mg in saline or 20% glucose, 1 g/min for 60 min, 11 subjects). After the blockade of dopamine receptors, a significant and prolonged increase of prolactin concentration was found. However, the levels of glucose, insulin, and C-peptide either before or after the glucose load were not different from control ones. The decreased number of insulin receptors (1.97 +/- 0.41 vs 0.51 +/- 0.14 pmol per 2.10(9) red blood cells) was compensated by increased affinity (0.51 +/- 0.17 vs 1.00 +/- 0.22 Ke 10(8) mol.-1 per l]) of insulin receptors. The stimulation of dopamine receptors showed a negligible effect on glucose regulation. It may be suggested that an endogenous increase of prolactin concentration in the physiological range does not participate in the regulation of glucose homeostasis in healthy subjects. PMID:8130181

  16. Fever is not responsible for the elevated glucose kinetics in sepsis

    SciTech Connect

    Lang, C.H.; Bagby, G.J.; Blakesley, H.L.; Spitzer, J.J.

    1987-09-01

    Previous studies have suggested that alterations in the classical neuroendocrine system may not be responsible for the increased glucose metabolism observed during hypermetabolic sepsis. The purpose of the present study was to determine whether inhibition of the cyclooxygenase pathway with indomethacin, which prevents the production of arachidonic acid metabolites by this pathway and the sepsis-induced increase in body temperature, would abolish the increases in glucose appearance (Ra), recycling, and hyperlactacidemia. Sepsis was induced in chronically catheterized conscious rats by multiple injections of live Escherichia coli via a subcutaneous catheter. Septic animals received iv injections of indomethacin every 6-8 hr to block the cyclooxygenase pathway. Glucose kinetics were assessed in 24-hr fasted rats using a constant iv infusion of (6-/sup 3/H)- and (U-/sup 14/C) glucose. Treatment with indomethacin prevented the 1-2/sup 0/C increase in body temperature observed in septic animals. Septic rats exhibited an elevated plasma lactate concentration and increased rates of glucose appearance and recycling. The sepsis-induced alterations in these variables were not attenuated by indomethacin. These results suggest that neither elevated body temperature nor the generation of arachidonic acid metabolites of the cyclooxygenase pathway is responsible for increasing glucose production in hypermetabolic septic rats.

  17. Microdegree porlarimetry for glucose concentrations detection

    NASA Astrophysics Data System (ADS)

    Wang, Hong; Wei, Yunlong; Zhou, Qi; Liu, Shenping; Chui, Jianguo

    2005-07-01

    Optical glucose measurement is an attractive research topic for years. One of the goals is to develop a noninvasive monitoring of long term, instantaneous blood glucose for diabetics. The principle of porlarimetry for glucose detection is introduced and several techniques of microdegree porlarimetry for glucose detection are summarized and the facts that effect measurement are discussed. Current and future research is focusing on the elimination of confounding factors such as other optically active substances for precise glucose detection.

  18. Elevated hair cortisol concentrations in endurance athletes.

    PubMed

    Skoluda, Nadine; Dettenborn, Lucia; Stalder, Tobias; Kirschbaum, Clemens

    2012-05-01

    Engaging in intensive aerobic exercise, specifically endurance sports, is associated with HPA axis activation indicated by elevated cortisol levels. Whether the repeated short-term elevations in cortisol levels result in higher long-term cortisol exposure of endurance athletes has been difficult to examine since traditional methods of cortisol assessments (saliva, blood, urine) reflect only relatively short time periods. Hair segment analysis provides a new method to assess cumulative cortisol secretion over prolonged time periods in a retrospective fashion. The aim of this study was to investigate cumulative cortisol secretion over several months reflecting intensive training and competitive races by examining hair cortisol levels of endurance athletes. Hair samples were obtained from 304 amateur endurance athletes (long-distance runners, triathletes, cyclists) and 70 controls. Cortisol concentrations were determined in the first to third 3-cm hair segments most proximal to the scalp. In addition, self-report measures of training volume were obtained. Endurance athletes exhibited higher cortisol levels in all three hair segments compared to controls (p<.001). Positive correlations between the cortisol concentration in the first hair segment and each indicator of training volume were found (all p<.01). These data suggest that repeated physical stress of intensive training and competitive races among endurance athletes is associated with elevated cortisol exposure over prolonged periods of time. These findings may have important implications with regard to somatic and mental health of athletes which should be investigated in future research. PMID:21944954

  19. Enzymatic Glucose Sensor Compensation for Variations in Ambient Oxygen Concentration

    PubMed Central

    Collier, Bradley B.; McShane, Michael J.

    2014-01-01

    Due to the increasing prevalence of diabetes, research toward painless glucose sensing continues. Oxygen sensitive phosphors with glucose oxidase (GOx) can be used to determine glucose levels indirectly by monitoring oxygen consumption. This is an attractive combination because of its speed and specificity. Packaging these molecules together in “smart materials” for implantation will enable non-invasive glucose monitoring. As glucose levels increase, oxygen levels decrease; consequently, the luminescence intensity and lifetime of the phosphor increase. Although the response of the sensor is dependent on glucose concentration, the ambient oxygen concentration also plays a key role. This could lead to inaccurate glucose readings and increase the risk of hyper- or hypoglycemia. To mitigate this risk, the dependence of hydrogel glucose sensor response on oxygen levels was investigated and compensation methods explored. Sensors were calibrated at different oxygen concentrations using a single generic logistic equation, such that trends in oxygen-dependence were determined as varying parameters in the equation. Each parameter was found to be a function of oxygen concentration, such that the correct glucose calibration equation can be calculated if the oxygen level is known. Accuracy of compensation will be determined by developing an overall calibration, using both glucose and oxygen sensors in parallel, correcting for oxygen fluctuations in real time by intentionally varying oxygen, and calculating the error in actual and predicted glucose levels. While this method was developed for compensation of enzymatic glucose sensors, in principle it can also be implemented with other kinds of sensors utilizing oxidases. PMID:26257458

  20. Potentiometric measurement of glucose concentration with an immobilized glucose oxidase/catalase electrode.

    PubMed

    Wingard, L B; Liu, C C; Wolfson, S K; Yao, S J; Drash, A L

    1982-01-01

    A series of enzyme electrodes for measurement of glucose have been constructed. The electrodes contain glucose oxidase immobilized on platinum, either with or without co-immobilization of catalase. When placed in buffered glucose, the enzyme electrodes show a potentiometric response to glucose with respect to a Ag/AgCl reference electrode. This response is reproducible in the physiologic range of glucose concentrations. The immobilization technique, some of the environmental variables such as oxygen concentration and pH, and several compounds that might interfere with the selectivity of the enzyme electrodes for glucose have received preliminary study. This direct potentiometric approach is undergoing further evaluation to determine the basic electrochemical mechanism responsible for the potentiometric signal and whether it can be adapted for continuous in vivo monitoring of the glucose concentration in body fluids. PMID:7172983

  1. A novel fluorescent sensor protein for detecting changes in airway surface liquid glucose concentration

    PubMed Central

    Helassa, Nordine; Garnett, James P.; Farrant, Matthew; Khan, Faaizah; Pickup, John C.; Hahn, Klaus M.; MacNevin, Christopher J.; Tarran, Robert; Baines, Deborah L.

    2015-01-01

    Both lung disease and elevation of blood glucose are associated with increased glucose concentration (from 0.4 to ~4.0 mM) in the airway surface liquid (ASL). This perturbation of ASL glucose makes the airway more susceptible to infection by respiratory pathogens. ASL is minute (~1 μl/cm2) and the measurement of glucose concentration in the small volume ASL is extremely difficult. Therefore, we sought to develop a fluorescent biosensor with sufficient sensitivity to determine glucose concentrations in ASL in situ. We coupled a range of environmentally sensitive fluorophores to mutated forms of a glucose/galactose-binding protein (GBP) including H152C and H152C/A213R and determined their equilibrium binding properties. Of these, GBP H152C/A213R–BADAN (Kd 0.86 ± 0.01 mM, Fmax/F0 3.6) was optimal for glucose sensing and in ASL increased fluorescence when basolateral glucose concentration was raised from 1 to 20 mM. Moreover, interpolation of the data showed that the glucose concentration in ASL was increased, with results similar to that using glucose oxidase analysis. The fluorescence of GBP H152C/A213R–BADAN in native ASL from human airway epithelial cultures in situ was significantly increased over time when basolateral glucose was increased from 5 to 20 mM. Overall our data indicate that this GBP is a useful tool to monitor glucose homoeostasis in the lung. PMID:25220254

  2. A novel fluorescent sensor protein for detecting changes in airway surface liquid glucose concentration.

    PubMed

    Helassa, Nordine; Garnett, James P; Farrant, Matthew; Khan, Faaizah; Pickup, John C; Hahn, Klaus M; MacNevin, Christopher J; Tarran, Robert; Baines, Deborah L

    2014-12-01

    Both lung disease and elevation of blood glucose are associated with increased glucose concentration (from 0.4 to ~4.0 mM) in the airway surface liquid (ASL). This perturbation of ASL glucose makes the airway more susceptible to infection by respiratory pathogens. ASL is minute (~1 μl/cm(2)) and the measurement of glucose concentration in the small volume ASL is extremely difficult. Therefore, we sought to develop a fluorescent biosensor with sufficient sensitivity to determine glucose concentrations in ASL in situ. We coupled a range of environmentally sensitive fluorophores to mutated forms of a glucose/galactose-binding protein (GBP) including H152C and H152C/A213R and determined their equilibrium binding properties. Of these, GBP H152C/A213R-BADAN (Kd 0.86 ± 0.01 mM, Fmax/F0 3.6) was optimal for glucose sensing and in ASL increased fluorescence when basolateral glucose concentration was raised from 1 to 20 mM. Moreover, interpolation of the data showed that the glucose concentration in ASL was increased, with results similar to that using glucose oxidase analysis. The fluorescence of GBP H152C/A213R-BADAN in native ASL from human airway epithelial cultures in situ was significantly increased over time when basolateral glucose was increased from 5 to 20 mM. Overall our data indicate that this GBP is a useful tool to monitor glucose homoeostasis in the lung. PMID:25220254

  3. Analysis of tear glucose concentration with electrospray ionization mass spectrometry.

    PubMed

    Taormina, Christopher R; Baca, Justin T; Asher, Sanford A; Grabowski, Joseph J; Finegold, David N

    2007-02-01

    We have developed a mass spectrometry-based method that allows one to accurately determine the glucose concentration of tear fluid. We used a 1 microL micro-capillary to collect tear fluid from the tear meniscus with minimal irritation of the eye. We analyzed the 1 muL volume of collected tear fluid with liquid-chromatography electrospray ionization mass spectrometry with the use of D-glucose-6,6-d2 as an internal standard. Repeated measurements and a recovery experiment on pooled, onion-induced tears showed that the analysis of the glucose in tears was precise (4% relative standard deviation) and provided 100% recovery. We found the tear glucose concentration of one fasting nondiabetic subject to be 13 to 51 microM while the onion-induced tear glucose concentration of a different nondiabetic subject to be 211 to 256 microM. PMID:17084090

  4. Analysis of Tear Glucose Concentration with Electrospray Ionization Mass Spectrometry

    PubMed Central

    Taormina, Christopher R.; Baca, Justin T.; Finegold, David N.; Asher, Sanford A.; Grabowski, Joseph J.

    2007-01-01

    We have developed a mass spectrometry-based method which allows one to accurately determine the glucose concentration of tear fluid. We used a 1 μL micro-capillary to collect tear fluid from the tear meniscus with minimal irritation of the eye. We analyzed the 1 μL volume of collected tear fluid with liquid-chromatography electrospray ionization mass spectrometry with the use of D-glucose-6,6-d2 as an internal standard. Repeated measurements and a recovery experiment on pooled, onion-induced tears showed that the analysis of the glucose in tears was precise (4% relative standard deviation) and provided 100% recovery. We found the tear glucose concentration of one fasting non-diabetic subject to be 13 to 51 μM while the onion-induced tear glucose concentration of a different non-diabetic subject to be 211 to 256 μM. PMID:17084090

  5. Modification and evolution of Gluconobacter oxydans for enhanced growth and biotransformation capabilities at low glucose concentration.

    PubMed

    Zhu, Kun; Lu, Leifang; Wei, Liujing; Wei, Dongzhi; Imanaka, Tadayuki; Hua, Qiang

    2011-09-01

    Gluconobacter oxydans is widely used in several biotechnological applications, where sorbitol or mannitol is commonly used as carbon source at high concentration. In this study, a membrane-bound glucose dehydrogenase-deficient strain (GDHK) was constructed to eliminate growth problems on glucose caused by direct oxidation of glucose in the medium. To achieve improved growth properties for the GDHK strain on glucose, a laboratory adaptive evolution experiment was performed with glucose as the sole carbon source. Results indicated evident, albeit modest, improvements in cell growth after a 50-day (about 430 generations) experimental evolution on glucose. The maximum specific growth rate and biomass yield of the resulting GDHE50 strain were increased around 1.35- to 1.4-fold compared with those of the GDHK strain. Meanwhile, two types of biotransformation reactions using resting cells of G. oxydans were investigated. Significant elevations in biotransformation performance of the GHDE50 strain were observed in comparison with that of the wild-type strain. In addition, resting cells of the GDHE50 strain grown on a relatively low concentration of glucose (10 g/l) could catalyze the biotransformation of glycerol to dihydroxyacetone and ethylene glycol to glycolic acid as efficient as the wild-type G. oxydans cultured on higher concentration of sorbitol or other carbon sources. These results suggest very favorable prospects of using glucose to lower production cost in many important industrial biocatalysis and biotransformation processes. PMID:21253895

  6. Continuous detection of glucose concentration by fluorescent indicator

    NASA Astrophysics Data System (ADS)

    Shi, Ting; Li, Dachao; Li, Guoqing; Lu, Lou; Xu, Kexin

    Continuous glucose detection has a great significance for diabetics. On the one hand, it can fully reflect the patient blood glucose change level. On the other hand, it can better guide the insulin dosage, and achieve closed-loop control of insulin pump. A continuous detection method of glucose concentration by borate polymer fluorescent indicator is proposed in the paper. The principle of this method is based on the competing reaction between alizarin, glucose and borate polymer. The borate polymer has high specific reaction with glucose, meanwhile reacts with non fluorescent alizarin. The product of the reaction between borate polymer and alizarin is fluorescent, called as fluorescent indicator. When glucose was introduced, the glucose molecules could react with the borate polymer in fluorescent indicator because of the high specificity. This competing process leads to the decomposition of fluorescent indicator into the non-fluorescent alizarin, and the fluorescent intensity gets loss. Therefore, the change of fluorescent intensity can reflect the glucose concentration level. In this method, the fluorescent indicator can well identify the glucose molecules. According to the experiment, we know that there is a high specific and good linear reaction between glucose and borate polymer. The linear fitting is up to 0.97 and the detection limitation can reach to 10 mg/dL. The fluorescent intensity reaches strongest with the optimal proportion of alizarin: borate polymer as 1:3. The reaction of the fluorescent indicator identifying glucose molecules has a good linear relationship, the linear fitting of which can reach to 0.98. The detection limitation can reach to 30 mg/dL, which fulfills the detection requirements of glucose concentration in vivo.

  7. Effect of high glucose concentrations on human erythrocytes in vitro

    PubMed Central

    Viskupicova, Jana; Blaskovic, Dusan; Galiniak, Sabina; Soszyński, Mirosław; Bartosz, Grzegorz; Horakova, Lubica; Sadowska-Bartosz, Izabela

    2015-01-01

    Exposure to high glucose concentrations in vitro is often employed as a model for understanding erythrocyte modifications in diabetes. However, effects of such experiments may be affected by glucose consumption during prolonged incubation and changes of cellular parameters conditioned by impaired energy balance. The aim of this study was to compare alterations in various red cell parameters in this type of experiment to differentiate between those affected by glycoxidation and those affected by energy imbalance. Erythrocytes were incubated with 5, 45 or 100 mM glucose for up to 72 h. High glucose concentrations intensified lipid peroxidation and loss of activities of erythrocyte enzymes (glutathione S-transferase and glutathione reductase). On the other hand, hemolysis, eryptosis, calcium accumulation, loss of glutathione and increase in the GSSG/GSH ratio were attenuated by high glucose apparently due to maintenance of energy supply to the cells. Loss of plasma membrane Ca2+-ATPase activity and decrease in superoxide production were not affected by glucose concentration, being seemingly determined by processes independent of both glycoxidation and energy depletion. These results point to the necessity of careful interpretation of data obtained in experiments, in which erythrocytes are subject to treatment with high glucose concentrations in vitro. PMID:26141922

  8. Depressive symptoms linked to 1-h plasma glucose concentrations during the oral glucose tolerance test in men and women with the metabolic syndrome

    PubMed Central

    Birnbaum-Weitzman, O.; Goldberg, R.; Hurwitz, B. E.; Llabre, M. M.; Gellman, M. D.; Gutt, M.; McCalla, J. R.; Mendez, A. J.; Schneiderman, N.

    2014-01-01

    Aims The addition of the 1-h plasma glucose concentration measure from an oral glucose tolerance test to prediction models of future Type 2 diabetes has shown to significantly strengthen their predictive power. The present study examined the relationship between severity of depressive symptoms and hyperglycaemia, focusing on the 1-h glucose concentration vs. fasting and 2-h oral glucose tolerance test glucose measures. Methods Participants included 140 adults with the metabolic syndrome and without diabetes who completed a baseline psychobiological assessment and a 2-h oral glucose tolerance test, with measurements taken every 30 min. Depressive symptoms were assessed using the Beck Depression Inventory. Results Multivariate linear regression revealed that higher levels of depressive symptoms were associated with higher levels of 1-h plasma glucose concentrations after adjusting for age, gender, ethnicity, BMI, antidepressant use and high-sensitivity C-reactive protein. Results were maintained after controlling for fasting glucose as well as for indices of insulin resistance and secretion. Neither fasting nor 2-h plasma glucose concentrations were significantly associated with depressive symptoms. Conclusions Elevated depressive symptoms in persons with the metabolic syndrome were associated with greater glycaemic excursion 1-h following a glucose load that was not accounted for by differences in insulin secretory function or insulin sensitivity. Consistent with previous findings, this study highlights the value of the 1-h oral glucose tolerance test plasma glucose measurement in the relation between depressive symptoms and glucose metabolism as an indicator of metabolic abnormalities not visible when focusing on fasting and 2-h post-oral glucose tolerance test measurements alone. PMID:24344735

  9. Increased maternal nighttime cortisol concentrations in late gestation alter glucose and insulin in the neonatal lamb

    PubMed Central

    Antolic, Andrew; Feng, Xiaodi; Wood, Charles E; Richards, Elaine M; Keller-Wood, Maureen

    2015-01-01

    Previous studies in our laboratory have shown that a modest chronic increase in maternal cortisol concentrations impairs maternal glucose metabolism and increases the incidence of perinatal stillbirth. The dramatic outcomes prevented our ability to study the effects of maternal hypercortisolemia on neonatal growth, glucose metabolism, and hypothalamo–pituitary–adrenal axis response. Therefore, we developed a model in which pregnant ewes are infused for 12 h/day at 0.5 mg·kg–1·day–1 from day 115 of gestation until delivery (˜145), elevating nighttime plasma cortisol concentrations. This pattern of elevation of cortisol mimics that in patients with elevated evening cortisol concentrations, as in Cushing’s syndrome or chronic depression. Plasma cortisol, glucose, insulin, and electrolytes were measured during pregnancy and postpartum in control and cortisol-infused ewes and their postnatal lambs for the first 14 days after delivery. Neonatal growth and plasma ACTH, aldosterone, renin activity, and electrolytes, and organ weights at 14 days of age were also measured. Infusion of cortisol increased maternal plasma cortisol during pregnancy but not postpartum, and did not alter neonatal ACTH or cortisol. Although maternal glucose and insulin concentrations were not changed by the maternal infusion of cortisol, neonatal plasma glucose was increased and plasma insulin was decreased compared to those in the control group. Neonatal ponderal index and kidney weight were reduced, left ventricular wall thickness was increased, and plasma sodium and creatinine were increased after maternal cortisol infusion. These results suggest that excess maternal cortisol concentrations in late gestation alter growth, glucose and insulin regulation, and organ maturation in the neonate. PMID:26371232

  10. Effect of Cinnamon Tea on Postprandial Glucose Concentration

    PubMed Central

    Bernardo, Maria Alexandra; Silva, Maria Leonor; Santos, Elisabeth; Moncada, Margarida Maria; Brito, José; Proença, Luis; Singh, Jaipaul; de Mesquita, Maria Fernanda

    2015-01-01

    Glycaemic control, in particular at postprandial period, has a key role in prevention of different diseases, including diabetes and cardiovascular events. Previous studies suggest that postprandial high blood glucose levels (BGL) can lead to an oxidative stress status, which is associated with metabolic alterations. Cinnamon powder has demonstrated a beneficial effect on postprandial glucose homeostasis in animals and human models. The purpose of this study is to investigate the effect of cinnamon tea (C. burmannii) on postprandial capillary blood glucose level on nondiabetic adults. Participants were given oral glucose tolerance test either with or without cinnamon tea in a randomized clinical trial. The data revealed that cinnamon tea administration slightly decreased postprandial BGL. Cinnamon tea ingestion also results in a significantly lower postprandial maximum glucose concentration and variation of maximum glucose concentration (p < 0.05). Chemical analysis showed that cinnamon tea has a high antioxidant capacity, which may be due to its polyphenol content. The present study provides evidence that cinnamon tea, obtained from C. burmannii, could be beneficial for controlling glucose metabolism in nondiabetic adults during postprandial period. PMID:26258147

  11. Optical detection of glucose concentration in samples with scattering particles.

    PubMed

    Lin, Li-Han; Lo, Yu-Lung; Liao, Chia-Chi; Lin, Jian-Xiang

    2015-12-10

    An optical-based method is proposed for measuring the glucose concentration of samples containing scattering particles. In the proposed approach, a Stokes-Mueller reflection-based polarimetry technique is used to solve the Mueller matrices of a turbid glucose sample with circular birefringence and depolarization properties given six incident lights with different polarization states. Using an error function defined as the difference between the simulated output Stokes vectors and the experimental ones, a genetic algorithm is used to inversely derive the optical rotation and depolarization parameters of the experimental sample corresponding to the glucose concentration and scattering depolarization effect, respectively. The validity of the proposed method is demonstrated using glucose samples containing 0.02 ml and 0.04 ml lipofundin, respectively. PMID:26836866

  12. Decrease in the plasma von Willebrand factor concentration following glucose ingestion: the role of insulin sensitivity.

    PubMed

    von Känel, R; Nelesen, R A; Le, D T; Ziegler, M G; Dimsdale, J E

    2001-12-01

    Elevated plasma von Willebrand factor (vWF) concentration is thought to be associated with increased prevalence of cardiovascular events in the insulin resistance syndrome. We examined the effects of oral glucose challenge and accompanying metabolic and hemodynamic changes on vWF levels with respect to insulin sensitivity. Forty normotensive and hypertensive subjects (mean age +/- SD, 40 +/- 5 years) underwent a standard oral glucose tolerance test (OGTT). Plasma vWF antigen, glucose, insulin, catecholamines, and hemodynamics were measured at rest, and at 30, 60, 90, and 120 minutes after glucose intake. Insulin sensitivity was determined by the insulin sensitivity index (ISI(0,120)). Resting plasma vWF concentration was associated with screening systolic blood pressure (BP) (r =.43, P =.005). There were time effects for all variables of interest. While vWF antigen (P =.044), epinephrine (P =.003), and diastolic BP (P =.001) decreased after glucose challenge, norepinephrine (P =.009), systolic BP (P =.022), and heart rate (P <.001) increased. Decline in vWF (area under the curve) was associated with decrease in epinephrine (r =.46, P =.004) and with screening systolic BP (r =.45, P =.004). However, neither resting plasma vWF levels nor vWF decrease following glucose ingestion were significantly associated with the ISI(0,120.) The plasma vWF concentration decreases following glucose ingestion. While mechanisms underlying this phenomenon may relate to sympathetic nervous system function, they seem not related to insulin sensitivity. Endothelial dysfunction such as caused by hypertension rather than metabolic dysregulation per se may underlie the elevated plasma vWF concentration found with insulin resistance. PMID:11735092

  13. The effect of dietary starch level on postprandial glucose and insulin concentrations in cats and dogs.

    PubMed

    Hewson-Hughes, Adrian K; Gilham, Matthew S; Upton, Sarah; Colyer, Alison; Butterwick, Richard; Miller, Andrew T

    2011-10-01

    A charge made against feeding dry foods to cats is that the high carbohydrate (i.e. starch) content results in high blood glucose levels which over time may have detrimental health effects. The present study determined the post-meal concentrations of plasma glucose and insulin in adult cats (seven males and four females) and dogs (Labrador retrievers; four males and five females) fed dry diets with low-starch (LS), moderate-starch (MS) or high-starch (HS) levels. In a cross-over design with at least 7 d between the test meals, plasma glucose and insulin concentrations were measured following a single meal of a LS, MS and HS diet (209 kJ/kg bodyweight). Only the HS diet resulted in significant post-meal increases in plasma glucose concentration in cats and dogs although the time-course profiles were different between the species. In cats, plasma glucose concentration was significantly increased above the pre-meal concentration from 11 h until 19 h after the meal, while in dogs, a significant increase above baseline was seen only at the 7 h time point. Plasma insulin was significantly elevated in dogs 4-8 h following the MS diet and 2-8 h after the HS diet. In cats, plasma insulin was significantly greater than baseline from 3-7 and 11-17 h after the HS diet. The time lag (approximately 11 h) between eating the HS diet and the subsequent prolonged elevation of plasma glucose concentration seen in cats may reflect metabolic adaptations that result in a slower digestive and absorptive capacity for complex carbohydrate. PMID:22005401

  14. Urinary phthalate metabolite concentrations and blood glucose levels during pregnancy

    PubMed Central

    Robledo, Candace A.; Peck, Jennifer D.; Stoner, Julie; Calafat, Antonia M.; Carabin, Hélène; Cowan, Linda; Goodman, Jean R.

    2016-01-01

    Purpose To examine associations between phthalate metabolite urinary concentrations during early pregnancy and blood glucose levels obtained at the time of screening for gestational diabetes mellitus (GDM). Methods Upon initiation of prenatal care, women with a mean gestational age of 12.8 weeks were recruited for a study of environmental chemical exposures (n = 110) and provided a spot urinary specimen. Blood glucose concentrations (mg/dl) were obtained from the electronic medical record for those patients who did not experience a pregnancy loss and did not transfer care to another facility prior to glucose screening (n = 72). Urinary concentrations of nine phthalate metabolites and creatinine were measured at the US Centers for Disease Control and Prevention. Associations between tertiles of phthalate metabolites concentrations and blood glucose levels were estimated using linear regression. Results Compared to pregnant women in the lowest concentration tertile, women with the highest urinary concentrations (≥3rd tertile) of mono-iso-butyl phthalate (tertile: ≥15.3 μg/l, β = −18.3, 95% CI: −35.4, −1.2) and monobenzyl phthalate (tertile: ≥30.3 μg/l, β = −17.3, 95% CI: −34.1, −0.4) had lower blood glucose levels at the time of GDM screening after adjustment for urinary creatinine and demographic covariates. Conclusion Because maternal glucose levels increase during pregnancy to provide adequate nutrition for fetal growth and development, these findings may have implications for fetal health. However, given the limitations of our study, findings should be interpreted cautiously. PMID:25726127

  15. Portable system for the detection of micromolar concentrations of glucose

    PubMed Central

    Kostov, Yordan; Ge, Xudong; Rao, Govind; Tolosa, Leah

    2014-01-01

    Glucose in non-invasively collected biofluids is generally in the micromolar range and thus, requires sensing methodologies capable of measuring glucose at these levels. Here, we present a small fluorometer system that can quantify glucose in the range of 0–5 μM with resolution of ~0.07 μM. It relies on the glucose binding protein (GBP) fluorescently labeled with two fluorophores. Fluorescence signals from the dual-labeled GBP are utilized in a ratiometric mode, making the measurements insensitive to variations in protein concentration and other systematic errors. Fluorescence is quantified by a miniature, dedicated ratiometric fluorometer that is powered via USB. Concentration is calculated using an ultra-mobile personal computer (UMPC). The whole system is designed to be pocket sized suitable for point-of-care or bedside applications. Test results suggest that the system is a promising tool for accurate measurements of low glucose concentrations (0.1–10 μM) in biological samples. PMID:24587594

  16. The sweet life: diet sugar concentration influences paracellular glucose absorption.

    PubMed

    Napier, Kathryn R; Purchase, Cromwell; McWhorter, Todd J; Nicolson, Susan W; Fleming, Patricia A

    2008-10-23

    Small birds and bats face strong selection pressure to digest food rapidly in order to reduce digesta mass carried during flight. One mechanism is rapid absorption of a high proportion of glucose via the paracellular pathway (transfer between epithelial cells, not mediated by transporter proteins). Intestinal paracellular permeability to glucose was assessed for two nectarivorous passerines, the Australian New Holland honeyeater (Phylidonyris novaehollandiae) and African white-bellied sunbird (Cinnyris talatala) by measuring the bioavailability of radiolabelled, passively absorbed L-glucose. Bioavailability was high in both species and increased with diet sugar concentration (honeyeaters, 37 and 81% and sunbirds, 53 and 71% for 250 and 1,000 mmoll-1 sucrose diets, respectively). We conclude that the relative contribution of paracellular to total glucose absorption increases with greater digesta retention time in the intestine, and paracellular absorption may also be modulated by factors such as intestinal lumen osmolality and interaction with mediated glucose uptake. The dynamic state of paracellular absorption should be taken into account in future studies. PMID:18559309

  17. Fluorescence lifetime measurements of boronate derivatives to determine glucose concentration

    SciTech Connect

    Gable, J H

    2000-06-01

    A novel investigation into the fluorescence lifetimes of molecules, both established and newly designed, was performed. These molecules are the basis of a continuous, minimally invasive, glucose sensor based on fluorescence lifetime measurements. This sensor, if coupled with an automated insulin delivery device, would effectively create an artificial pancreas allowing for the constant monitoring and control of glucose levels in a person with diabetes. The proposed sensor includes a fluorescent molecule that changes its' fluorescence properties upon binding selectively and reversibly to glucose. One possible sensor molecule is N-methyl-N-(9-methylene anthryl)-2-methylenephenylboronic acid (AB). The fluorescence intensity of AB was shown to change in response to changing glucose concentrations. (James, 1994) James proposed that when glucose binds to AB the fluorescence intensity increases due to an enhancement of the N{yields}B dative bond which prevents photoinduced electron transfer (PET). PET from the amine (N) to the fluorophore (anthracene) quenches the fluorescence. The dative bond between the boron and the amine can prevent PET by involving the lone pair of electrons on the amine in interactions with the boron rather than allowing them to be transferred to the fluorophore. Results of this research show the average fluorescence lifetime of AB also changes with glucose concentration. It is proposed that fluorescence is due to two components: (1) AB with an enhanced N{yields}B interaction, and no PET, and (2) AB with a weak N{yields}B interaction, resulting in fluorescence quenching by PET. Lifetime measurements of AB as a function of both the pH of the solvent and glucose concentration in the solution were made to characterize this two component system and investigate the nature of the N{yields}B bond. Measurements of molecules similar to AB were also performed in order to isolate behavior of specific AB constituents. These molecules are 9-(Methylaminomethyl

  18. Elevated glucose levels impair the WNT/β-catenin pathway via the activation of the hexosamine biosynthesis pathway in endometrial cancer.

    PubMed

    Zhou, Fuxing; Huo, Junwei; Liu, Yu; Liu, Haixia; Liu, Gaowei; Chen, Ying; Chen, Biliang

    2016-05-01

    Endometrial cancer (EC) is one of the most common gynecological malignancies in the world. Associations between fasting glucose levels (greater than 5.6mmol/L) and the risk of cancer fatality have been reported. However, the underlying link between glucose metabolic disease and EC remains unclear. In the present study, we explored the influence of elevated glucose levels on the WNT/β-catenin pathway in EC. Previous studies have suggested that elevated concentrations of glucose can drive the hexosamine biosynthesis pathway (HBP) flux, thereby enhancing the O-GlcNAc modification of proteins. Here, we cultured EC cell lines, AN3CA and HEC-1-B, with various concentrations of glucose. Results showed that when treated with high levels of glucose, both lines showed increased expression of β-catenin and O-GlcNAcylation levels; however, these effects could be abolished by the HBP inhibitors, Azaserine and 6-Diazo-5-oxo-l-norleucine, and be restored by glucosamine. Moreover the AN3CA and HEC-1-B cells that were cultured with or without PUGNAc, an inhibitor of the O-GlcNAcase, showed that PUGNAc increased β-catenin levels. The results suggest that elevated glucose levels increase β-catenin expression via the activation of the HBP in EC cells. Subcellular fractionation experiments showed that AN3CA cells had a higher expression of intranuclear β-catenin in high glucose medium. Furthermore, TOP/FOP-Flash and RT-PCR results showed that glucose-induced increased expression of β-catenin triggered the transcription of target genes. In conclusion, elevated glucose levels, via HBP, increase the O-GlcNAcylation level, thereby inducing the over expression of β-catenin and subsequent transcription of the target genes in EC cells. PMID:26923859

  19. SLEEP/WAKE DEPENDENT CHANGES IN CORTICAL GLUCOSE CONCENTRATIONS

    PubMed Central

    Dash, Michael B; Bellesi, Michele; Tononi, Giulio; Cirelli, Chiara

    2012-01-01

    Most of the energy in the brain comes from glucose and supports glutamatergic activity. The firing rate of cortical glutamatergic neurons, as well as cortical extracellular glutamate levels, increase with time spent awake and decline throughout non rapid eye movement (NREM) sleep, raising the question whether glucose levels reflect behavioral state and sleep/wake history. Here chronic (2–3 days) electroencephalographic (EEG) recordings in the rat cerebral cortex were coupled with fixed-potential amperometry to monitor the extracellular concentration of glucose ([gluc]) on a second-by-second basis across the spontaneous sleep-wake cycle and in response to 3 hours of sleep deprivation. [Gluc] progressively increased during NREM sleep and declined during REM sleep, while during wake an early decline in [gluc] was followed by an increase 8–15 minutes after awakening. There was a significant time of day effect during the dark phase, when rats are mostly awake, with [gluc] being significantly lower during the last 3–4 hours of the night relative to the first 3–4 hours. Moreover, the duration of the early phase of [gluc] decline during wake was longer after prolonged wake than after consolidated sleep. Thus, the sleep/wake history may affect the levels of glucose available to the brain upon awakening. PMID:23106535

  20. Identification of Risk Factors for Elevated Neonatal Gentamicin Trough Concentrations

    PubMed Central

    Ahern, John; Noyes, Elizabeth; Corriveau, Michele; Mercier, Charles

    2016-01-01

    OBJECTIVES: The objective of this study was to identify neonatal and maternal characteristics that may be associated with elevated neonatal gentamicin trough concentrations despite application of a previously published gentamicin dosage strategy. METHODS: Retrospective cohort study of all neonates admitted to University of Vermont Medical Center (562-bed academic teaching hospital, Burlington, VT) receiving gentamicin between June 1, 2009, and August 31, 2013. A total of 205 neonates were included, with 41 cases and 164 controls. RESULTS: Postmenstrual age (PMA, gestational age plus chronological age) and small-for–gestational age (SGA) status were independently associated with elevated neonatal gentamicin trough concentrations. No maternal risk factor evaluated remained significantly associated in the multivariate analysis. CONCLUSIONS: The probability of an elevated gentamicin trough concentration increases with lower PMA and is further accentuated in neonates with SGA status. In contrast, the presence of maternal risk factors did not increase the likelihood of elevated gentamicin trough concentrations. Neonates with lower PMA and SGA status may require an individualized dosage and monitoring strategy. PMID:27199620

  1. Detection of saliva-range glucose concentrations using organic thin-film transistors

    NASA Astrophysics Data System (ADS)

    Elkington, D.; Belcher, W. J.; Dastoor, P. C.; Zhou, X. J.

    2014-07-01

    We describe the development of a glucose sensor through direct incorporation of an enzyme (glucose oxidase) into the gate of an organic thin film transistor (OTFT). We show that glucose diffusion is the key determinant of the device response time and present a mechanism of glucose sensing in these devices that involves protonic doping of the transistor channel via enzymatic oxidation of glucose. The integrated OTFT sensor is sensitive across 4 decades of glucose concentration; a range that encompasses both the blood and salivary glucose concentration levels. As such, this work acts as a proof-of-concept for low-cost printed biosensors for salivary glucose.

  2. Detection of saliva-range glucose concentrations using organic thin-film transistors

    SciTech Connect

    Elkington, D.; Belcher, W. J.; Dastoor, P. C.; Zhou, X. J.

    2014-07-28

    We describe the development of a glucose sensor through direct incorporation of an enzyme (glucose oxidase) into the gate of an organic thin film transistor (OTFT). We show that glucose diffusion is the key determinant of the device response time and present a mechanism of glucose sensing in these devices that involves protonic doping of the transistor channel via enzymatic oxidation of glucose. The integrated OTFT sensor is sensitive across 4 decades of glucose concentration; a range that encompasses both the blood and salivary glucose concentration levels. As such, this work acts as a proof-of-concept for low-cost printed biosensors for salivary glucose.

  3. Elevated non-esterified fatty acid concentrations during bovine oocyte maturation compromise early embryo physiology.

    PubMed

    Van Hoeck, Veerle; Sturmey, Roger G; Bermejo-Alvarez, Pablo; Rizos, Dimitrios; Gutierrez-Adan, Alfonso; Leese, Henry J; Bols, Peter E J; Leroy, Jo L M R

    2011-01-01

    Elevated concentrations of serum non-esterified fatty acids (NEFA), associated with maternal disorders such as obesity and type II diabetes, alter the ovarian follicular micro-environment and have been associated with subfertility arising from reduced oocyte developmental competence. We have asked whether elevated NEFA concentrations during oocyte maturation affect the development and physiology of zygotes formed from such oocytes, using the cow as a model. The zygotes were grown to blastocysts, which were evaluated for their quality in terms of cell number, apoptosis, expression of key genes, amino acid turnover and oxidative metabolism. Oocyte maturation under elevated NEFA concentrations resulted in blastocysts with significantly lower cell number, increased apoptotic cell ratio and altered mRNA abundance of DNMT3A, IGF2R and SLC2A1. In addition, the blastocysts displayed reduced oxygen, pyruvate and glucose consumption, up-regulated lactate consumption and higher amino acid metabolism. These data indicate that exposure of maturing oocytes to elevated NEFA concentrations has a negative impact on fertility not only through a reduction in oocyte developmental capacity but through compromised early embryo quality, viability and metabolism. PMID:21858021

  4. Genistein improves spatial learning and memory in male rats with elevated glucose level during memory consolidation.

    PubMed

    Kohara, Yumi; Kawaguchi, Shinichiro; Kuwahara, Rika; Uchida, Yutaro; Oku, Yushi; Yamashita, Kimihiro

    2015-03-01

    Cognitive dysfunction due to higher blood glucose level has been reported previously. Genistein (GEN) is a phytoestrogen that we hypothesized might lead to improved memory, despite elevated blood glucose levels at the time of memory consolidation. To investigate this hypothesis, we compared the effects of orally administered GEN on the central nervous system in normal versus glucose-loaded adult male rats. A battery of behavioral assessments was carried out. In the MAZE test, which measured spatial learning and memory, the time of normal rats was shortened by GEN treatment compared to the vehicle group, but only in the early stages of testing. In the glucose-loaded group, GEN treatment improved performance as mazes were advanced. In the open-field test, GEN treatment delayed habituation to the new environment in normal rats, and increased the exploratory behaviors of glucose-loaded rats. There were no significant differences observed for emotionality or fear-motivated learning and memory. Together, these results indicate that GEN treatment improved spatial learning and memory only in the early stages of testing in the normal state, but improved spatial learning and memory when glucose levels increased during memory consolidation. PMID:25481356

  5. Elevated carbon dioxide concentrations and whole plant senescence

    SciTech Connect

    St. Omer, L.; Horvath, S.M.

    1983-10-01

    Investigations concerned with the effects of elevated atmospheric CO/sub 2/ on plant growth and senescence have generally involved short-term exposures. This report concerns the effects of lifetime exposures to elevated CO/sub 2/ levels in three native winter annual plant species on biomass accumulation, induction of flowering, leaf senescence, and death of whole plants. Life span was significantly (P < .05) reduced in Layia platyglossa and Clarkia rubicunda at the highest CO/sub 2/ concentrations (0.21%). Flower initiation was significantly (P < .05) accelerated for Layia platyglossa and Clarkia rubicunda at 0.14 and 0.21% CO. Dry matter accumulation (biomass) of Layia and Clarkia increased with increasing concentrations of atmospheric CO/sub 2/. The number of senesced leaves per plant during the early stages of development (pre-anthesis, 105 d) was not significantly different for CO/sub 2/ treatments for either Nemophila menziesii or Layia platyglossa.

  6. Effects of intraduodenal administration of HCl and glucose on circulating immunoreactive secretin and insulin concentrations.

    PubMed

    Boden, G; Essa, N; Owen, O E; Reichle, F A

    1974-04-01

    A new radioimmunoassay for secretin was used to investigate (a) serum secretin responses to intraduodenally infused HCl and glucose, (b) the metabolic half-life and the volume of distribution of exogenous secretin and (c) the effect of endogenously released secretin on insulin secretion in 25 anesthetized dogs. Portal and femoral venous blood samples were taken simultaneously before, during, and after intraduodenal infusion of HCl (21 meq/30 min) and glucose (131 ml/30 min). Control experiments were performed with intraduodenal infusion of saline. Mean portal venous immunoreactive secretin concentration of six dogs rose from 313 muU/ml before to 1,060 muU/ml 10 min after initiation of the intestinal acidification (P < 0.005). Femoral venous immunoreactive secretin concentration rose from 220 muU/ml before to 567 muU/ml 15 min after intestinal acidification (P < 0.01). Secretin concentrations remained elevated during the remainder of the infusion. In the same six dogs mean portal venous immunoreactive insulin concentration rose from 38 muU/ml before to 62 muU/ml at the end of the infusion (P < 0.05). Peripheral immunoreactive insulin, glucose, and free fatty acid concentrations, however, did not change significantly. Pancreatic exocrine function was studied in four dogs. The rise in secretin concentration was followed promptly by a highly significant increase in exocrine pancreatic flow rate and bicarbonate secretion, indicating biological activity of the circulating immunoreactive secretin. The effect of intraduodenal infusion of glucose on immunoreactive secretin concentration was studied in 12 dogs. Glucose in concentrations ranging from 2.5% to 10% had no detectable influence on portal or peripheral secretin concentration. Infusion of 50% glucose caused a slight decline in secretin concentration. The metabolic clearance rate, half-life of disappearance, and volume of distribution of exogenous secretin was studied in three dogs by the constant infusion technic

  7. Effects of Intraduodenal Administration of HCl and Glucose on Circulating Immunoreactive Secretin and Insulin Concentrations

    PubMed Central

    Boden, Guenther; Essa, Noorjehan; Owen, Oliver E.; Reichle, Frederick A.; Saraga, Walter

    1974-01-01

    A new radioimmunoassay for secretin was used to investigate (a) serum secretin responses to intraduodenally infused HCl and glucose, (b) the metabolic half-life and the volume of distribution of exogenous secretin and (c) the effect of endogenously released secretin on insulin secretion in 25 anesthetized dogs. Portal and femoral venous blood samples were taken simultaneously before, during, and after intraduodenal infusion of HCl (21 meq/30 min) and glucose (131 ml/30 min). Control experiments were performed with intraduodenal infusion of saline. Mean portal venous immunoreactive secretin concentration of six dogs rose from 313 μU/ml before to 1,060 μU/ml 10 min after initiation of the intestinal acidification (P < 0.005). Femoral venous immunoreactive secretin concentration rose from 220 μU/ml before to 567 μU/ml 15 min after intestinal acidification (P < 0.01). Secretin concentrations remained elevated during the remainder of the infusion. In the same six dogs mean portal venous immunoreactive insulin concentration rose from 38 μU/ml before to 62 μU/ml at the end of the infusion (P < 0.05). Peripheral immunoreactive insulin, glucose, and free fatty acid concentrations, however, did not change significantly. Pancreatic exocrine function was studied in four dogs. The rise in secretin concentration was followed promptly by a highly significant increase in exocrine pancreatic flow rate and bicarbonate secretion, indicating biological activity of the circulating immunoreactive secretin. The effect of intraduodenal infusion of glucose on immunoreactive secretin concentration was studied in 12 dogs. Glucose in concentrations ranging from 2.5% to 10% had no detectable influence on portal or peripheral secretin concentration. Infusion of 50% glucose caused a slight decline in secretin concentration. The metabolic clearance rate, half-life of disappearance, and volume of distribution of exogenous secretin was studied in three dogs by the constant infusion technic

  8. Blood glucose monitor: an alternative off-line method to measure glucose concentration during fermentations with Trichoderma reesei.

    PubMed

    Choy, Viviane; Patel, Nilesh; Thibault, Jules

    2007-07-01

    Two home, blood-glucose monitoring meters, OneTouch Ultra and Ascensia Contour, were used to determine the glucose concentration during fermentations of Trichoderma reesei in both flasks and bioreactors. The results, when compared to those given by the 3,5-dinitrosalicylic acid reducing sugar assay, HPLC and YSI 2700 SELECT Biochemistry analyzer, showed that the glucose meters are a quick, reliable and economical alternative method for frequent glucose concentration measurement during fermentation. For T. reesei fermentations, the OneTouch meter was the more suitable. PMID:17377750

  9. Pre-exercise glucose ingestion at different time periods and blood glucose concentration during exercise.

    PubMed

    Tokmakidis, S P; Volaklis, K A

    2000-08-01

    The purpose of this study was to investigate the effects of glucose ingestion (GI) at different time periods prior to exercise on blood glucose (BG) levels during prolonged treadmill running. Eight subjects (X+/-SD), age 20+/-0.5yr, bodymass 70.7+/-4.1 kg, height 177+/-4 cm, VO2max 52.8+/-7.8 ml x kg(-1) x min(-1) who underwent different experimental conditions ingested a glucose solution (1 g/kg at 350 ml) 30 min (gl-30), 60 min (gl-60), 90 min (gl-90), and a placebo one 60 min (pl-60) prior to exercise in a counterbalanced design. Afterwards they ran at 65% of VO2max for 1 hour and then at 75 % of VO2max till exhaustion. Fingertip blood samples (10 microl) were drawn every 15 min before and during exercise for the determination of BG levels. Oxygen uptake (VO2), heart rate (HR), and blood lactate (La) were also measured every 15 min during exercise. Peak BG values were reached within 30 min after GI but were different (p < 0.01) at the onset of exercise (gl-30: 147+/-22, gl-60: 118+/-25, gl-90: 109+/-22, pl-60: 79+/-5mg/dl). The two-way ANOVA repeated measures and the Tukey post-hoc test revealed a higher BG concentration (p < 0.05) for the gl-30 and the pl-60 as compared to the gl-60 and gl-90 during running (e.g. 15min run: 82+/-11, 68+/-5, 64+/-3, 78+/-7, and 60min run: 98+/-12, 85+/-12, 83+/-11, 94+/-11 mg/dl for gl-30, gl-60, gl-90, and pl-60, respectively). However, this did not significantly affect the duration of treadmill running. The La levels were higher (p < 0.05) after GI as compared to placebo throughout exercise (values at exhaustion: 4.6+/-0.2, 5.0+/-1.5, 4.8+/- 1.7 mmol/l for gl-30, gl-60, gl-90, and 3.5+/-0.8 mmol/l for placebo). The gl-30 and the placebo fluctuated closer to normoglycaemic levels. The glucose ingestion (60 to 90 min) prior to exercise lowered the blood glucose levels without affecting the duration of running performance at 75% VO2max. Thus, in order to maintain normoglycaemic levels, pre-exercise glucose supplementation should

  10. Elevated major ion concentrations inhibit larval mayfly growth and development.

    PubMed

    Johnson, Brent R; Weaver, Paul C; Nietch, Christopher T; Lazorchak, James M; Struewing, Katherine A; Funk, David H

    2015-01-01

    Anthropogenic disturbances, including those from developing energy resources, can alter stream chemistry significantly by elevating total dissolved solids. Field studies have indicated that mayflies (Order Ephemeroptera) are particularly sensitive to high total dissolved solids. In the present study, the authors measured 20-d growth and survivorship of larval Neocloeon triangulifer exposed to a gradient of brine salt (mixed NaCl and CaCl2 ) concentrations. Daily growth rates were reduced significantly in all salt concentrations above the control (363 µS cm(-1) ) and larvae in treatments with specific conductance >812 µS cm(-1) were in comparatively earlier developmental stages (instars) at the end of the experiment. Survivorship declined significantly when specific conductance was >1513 µS cm(-1) and the calculated 20-d 50% lethal concentration was 2866 µS cm(-1) . The present study's results provide strong experimental evidence that elevated ion concentrations similar to those observed in developing energy resources, such as oil and gas drilling or coal mining, can adversely affect sensitive aquatic insect species. PMID:25307284

  11. Development of a novel noninvasive sensor for determination of blood glucose concentration

    NASA Astrophysics Data System (ADS)

    Boeckle, Stefan; Rovati, Luigi; Ansari, Rafat R.

    2001-10-01

    Optical methods represent the most promising techniques to perform non-invasive glucose detection. Glucose concentration in the aqueous humor closely mimics glucose levels in the blood and therefore non-invasive optical measurement of glucose can be performed by an optical beam crossing the eye anterior chamber. We propose a polarimetric method that exploits the Brewster-reflection of circularly polarized light on the lens of the eye. After reflection, the resulting linearly polarized light is subject to rotation by the glucose in the aqueous humor and thus carries the concentration information. A preliminary experimental setup, using glucose samples in a beaker, was realized and investigated.

  12. Exposure to low levels of hydrogen sulfide elevates circulating glucose in maternal rats

    SciTech Connect

    Hayden, L.J.; Goeden, H.; Roth, S.H. )

    1990-09-01

    Although the lethal effect of hydrogen sulfide (H{sub 2}S) has long been known, the results of exposure to low levels of H{sub 2}S have not been well documented. Rat dams and pups were exposed to low levels of H{sub 2}S (less than or equal to 75 ppm) from d 1 of gestation until d 21 postpartum and analyzed for changes in circulating enzymatic activity and metabolites. Blood glucose was significantly elevated in maternal blood on d 21 postpartum at all exposure levels. This increase in glucose was accompanied by a possible decrease in serum triglyceride in the pups and in the dams on d 21 postpartum. There was no evidence of alterations in serum alkaline phosphatase, lactate dehydrogenase, or serum glutamate oxaloacetate transaminase.

  13. Experimental and Natural Warming Elevates Mercury Concentrations in Estuarine Fish

    PubMed Central

    Dijkstra, Jennifer A.; Buckman, Kate L.; Ward, Darren; Evans, David W.; Dionne, Michele; Chen, Celia Y.

    2013-01-01

    Marine food webs are the most important link between the global contaminant, methylmercury (MeHg), and human exposure through consumption of seafood. Warming temperatures may increase human exposure to MeHg, a potent neurotoxin, by increasing MeHg production as well as bioaccumulation and trophic transfer through marine food webs. Studies of the effects of temperature on MeHg bioaccumulation are rare and no study has specifically related temperature to MeHg fate by linking laboratory experiments with natural field manipulations in coastal ecosystems. We performed laboratory and field experiments on MeHg accumulation under varying temperature regimes using the killifish, Fundulus heteroclitus. Temperature treatments were established in salt pools on a coastal salt marsh using a natural temperature gradient where killifish fed on natural food sources. Temperatures were manipulated across a wider range in laboratory experiments with killifish exposed to MeHg enriched food. In both laboratory microcosms and field mesocosms, MeHg concentrations in killifish significantly increased at elevated temperatures. Moreover, in field experiments, other ancillary variables (salinity, MeHg in sediment, etc.) did not relate to MeHg bioaccumulation. Modeling of laboratory experimental results suggested increases in metabolic rate as a driving factor. The elevated temperatures we tested are consistent with predicted trends in climate warming, and indicate that in the absence of confounding factors, warmer sea surface temperatures could result in greater in bioaccumulation of MeHg in fish, and consequently, increased human exposure. PMID:23554891

  14. Blood glucose concentration for predicting poor outcomes in patients with and without impaired glucose metabolism undergoing off-pump coronary artery bypass surgery – long-term observational study

    PubMed Central

    Majstrak, Franciszek; Opolski, Grzegorz; Filipiak, Krzysztof J.

    2016-01-01

    Introduction Strict glucose control is an everyday practice in the perioperative period. Elevated glucose level has a deleterious impact on clinical results, but a therapeutic target has not been stated yet. Aim To determine a glucose concentration range affecting long-term outcomes after coronary artery bypass surgery (CABG). Material and methods This study is a retrospective evaluation of consecutive patients treated in a university hospital in Poland from 2004 to 2008. Patients were divided into 2 groups: an impaired glucose metabolism group (IGM) if they had 1) known DM or 2) perioperative hyperglycaemia defined as ≥ 200 mg/dl; and a non-IGM group. The end point (EP) was all-cause mortality. Results One thousand two hundred and eleven patients were covered by the analysis. The observation time was from 01.01.2004 until 01.08.2012. Patients who had maximal glucose concentrations < 242 mg/dl had the lowest mortality risk (EP in 21.1%); a higher risk was noted in the group with glucose concentrations 242–324 mg/dl (EP in 30.8%); and a very high risk was found for the group where glucose concentration was > 324 mg/dl (EP in 44.2%) (p = 0.041). Patients with IGM had a shorter survival at the end of the study (p < 0.001). The longest survival was observed in patients whose maximal glucose level was ≤ 242 mg/dl (p < 0.001) and the minimal glucose concentration was in the range 61–110 mg/dl (p < 0.001). Conclusions Tight glucose concentration control should be performed irrespective of a diabetes diagnosis and proper treatment introduced when necessary. Maximal glucose concentration should be kept < 242 mg/dl, while the minimum should be in the range 60–110 mg/dl. PMID:27625687

  15. Aggregation ability of erythrocytes of patients with coronary heart disease depending on different glucose concentration

    NASA Astrophysics Data System (ADS)

    Malinova, Lidia I.; Simonenko, Georgy V.; Kirichuk, Vyacheslav F.; Denisova, Tatyana P.; Tuchin, Valery V.

    2002-07-01

    The aggregation ability of erythrocytes of patients with coronary heart disease comparing to practically healthy persons and patients with coronary heart disease combined with non insulin dependent diabetes mellitus depending on different glucose concentration in unguentums of blood incubates with the help of computer microphotometer - visual analyzer was studied. Two-phase behavior of erythrocytes size changing of practically healthy persons depending on glucose concentration in an incubation medium and instability erythrocyte systems of a whole blood to the influence of high glucose concentration were revealed. Influence of high glucose concentration on aggregation ability of erythrocytes of patients with coronary heart disease and its combination with non insulin dependent diabetes mellitus was revealed.

  16. Predictability of 1-h postload plasma glucose concentration: A 10-year retrospective cohort study

    PubMed Central

    Kuang, Lifen; Huang, Zhimin; Hong, Zhenzhen; Chen, Ailing; Li, Yanbing

    2015-01-01

    Aims/Introduction Elevated 1-h postload plasma glucose concentration (1hPG) during oral glucose tolerance test has been linked to an increased risk of type 2 diabetes and a poorer cardiometabolic risk profile. The present study analyzed the predictability and cut-off point of 1hPG in predicting type 2 diabetes in normal glucose regulation (NGR) subjects, and evaluated the long-term prognosis of NGR subjects with elevated 1hPG in glucose metabolism, kidney function, metabolic states and atherosclerosis. Materials and Methods A total of 116 Han Chinese classified as NGR in 2002 at the First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China, were investigated. Follow-up was carried out in 2012 to evaluate the progression of glucose metabolism, kidney function, metabolic syndrome and carotid atherosclerosis. Results The areas under receiver operating characteristic curves were higher for 1hPG than FPG or 2hPG (0.858 vs 0.806 vs 0.746). The cut-off value of 1hPG with the maximal sum of sensitivity and specificity in predicting type 2 diabetes in NGR subjects was 8.85 mmol/L. The accumulative incidence of type 2 diabetes in subjects with 1hPG ≥8.85 mmol/L was higher than those <8.85 mmol/L (46.2% vs 3.3%, P = 0.000; relative risk 13.846, 95% confidence interval 4.223–45.400). On follow up, the prevalence of metabolic syndrome and abnormal carotid intima-media thickness in the subjects with 1hPG ≥8.85 mmol/L tended to be higher compared with those <8.85 mmol/L. Conclusions 1hPG is a good predictor of type 2 diabetes in NGR subjects, and the best cut-off point is 8.85 mmol/L. Some tendency indicates that NGR subjects with 1hPG ≥8.85 mmol/L are more prone to metabolic syndrome and carotid atherosclerosis. PMID:26543538

  17. Glucose and cortisol concentrations in cows treated with a slowly-absorbed betamethasone suspension.

    PubMed

    MacDiarmid, S C; Cooper, B S

    1983-01-01

    A slowly-absorbed aqueous suspension of betamethasone, intended for use in the induction;of parturition, was administered to 10 cows. Each cow received 2ml (mean individual dose, 44.4 +/- 0.5microg/kg) by subcutaneous injection. Plasma samples were collected on six occasions over a seven-day period before treatment and on 21 occasions over a 29 day period after treatment. The mean concentration of betamethasone in plasma, as measured by radioimmunoassay, peaked at 0.6ng/ml24 hours after injection and was detectable for four days. Depression of the endogenous cortisol levels, as recorded with other long-acting synthetic glucocorticoids, was observed with this preparation of betamethasone. Plasma glucose was significantly elevated for eight days after betamethasone administration. PMID:16030908

  18. Determination of glucose concentration based on pulsed laser induced photoacoustic technique and least square fitting algorithm

    NASA Astrophysics Data System (ADS)

    Ren, Zhong; Liu, Guodong; Huang, Zhen

    2015-08-01

    In this paper, a noninvasive glucose concentration monitoring setup based on the photoacoustic technique was established. In this setup, a 532nm pumped Q switched Nd: YAG tunable pulsed laser with repetition rate of 20Hz was used as the photoacoustic excitation light source, and a ultrasonic transducer with central response frequency of 9.55MHz was used as the detector of the photoacoustic signal of glucose. As the preliminary exploration of the blood glucose concentration, a series of in vitro photoacoustic monitoring of glucose aqueous solutions by using the established photoacoustic setup were performed. The photoacoustic peak-to-peak values of different concentrations of glucose aqueous solutions induced by the pulsed laser with output wavelength of 1300nm to 2300nm in interval of 10nm were obtained with the average times of 512. The differential spectral and the first order derivative spectral method were used to get the characteristic wavelengths. For the characteristic wavelengths of glucose, the least square fitting algorithm was used to establish the relationship between the glucose concentrations and photoacoustic peak-to-peak values. The characteristic wavelengths and the predicted concentrations of glucose solution were obtained. Experimental results demonstrated that the prediction effect of characteristic wavelengths of 1410nm and 1510nm were better than others, and this photoacoustic setup and analysis method had a certain potential value in the monitoring of the blood glucose concentration.

  19. ELEVATED CO2 AND ELEVATED TEMPERATURE AFFECT CARBON AND NITROGEN CONCENTRATIONS BUT NOT ACCUMULATION IN PSEUDOTSUGA MENZIESII SEEDLINGS

    EPA Science Inventory

    To determine the impact of climate change on concentrations and accumulation of C and N in trees, we grew Pseudotsuga menziesii (Mirb.) Franco (Douglas-fir) seedlings treated with ambient or elevated (+180 mol mol-1) CO2, and with ambient or elevated (+3.5 C) temperature for f...

  20. Measurement of the glucose concentration in human urine with optical refractometer

    NASA Astrophysics Data System (ADS)

    Wu, Rui-Yang; Hsu, Cheng-Chih; Meng, Ching-Tang; Cheng, Chih-Ching; Liao, Yu-Ching

    2015-07-01

    In this paper, a new type of human urine glucose measurement system is proposed. We measured the phase variation of human urine with/without glucose-urine mixture (to simulate diabetes mellitus). We were able to achieve high resolution with the proposed method. The relation curve between the phase difference and glucose concentration can be estimated, and the glucose concentration of a urine sample can be determined by using this relation curve. The proposed method showed that theoretical resolution is approximated of 1.47 mg/dl.

  1. Measurement of glucose concentration by image processing of thin film slides

    NASA Astrophysics Data System (ADS)

    Piramanayagam, Sankaranaryanan; Saber, Eli; Heavner, David

    2012-02-01

    Measurement of glucose concentration is important for diagnosis and treatment of diabetes mellitus and other medical conditions. This paper describes a novel image-processing based approach for measuring glucose concentration. A fluid drop (patient sample) is placed on a thin film slide. Glucose, present in the sample, reacts with reagents on the slide to produce a color dye. The color intensity of the dye formed varies with glucose at different concentration levels. Current methods use spectrophotometry to determine the glucose level of the sample. Our proposed algorithm uses an image of the slide, captured at a specific wavelength, to automatically determine glucose concentration. The algorithm consists of two phases: training and testing. Training datasets consist of images at different concentration levels. The dye-occupied image region is first segmented using a Hough based technique and then an intensity based feature is calculated from the segmented region. Subsequently, a mathematical model that describes a relationship between the generated feature values and the given concentrations is obtained. During testing, the dye region of a test slide image is segmented followed by feature extraction. These two initial steps are similar to those done in training. However, in the final step, the algorithm uses the model (feature vs. concentration) obtained from the training and feature generated from test image to predict the unknown concentration. The performance of the image-based analysis was compared with that of a standard glucose analyzer.

  2. A predictive and feedback control algorithm maintains a constant glucose concentration in fed-batch fermentations.

    PubMed

    Kleman, G L; Chalmers, J J; Luli, G W; Strohl, W R

    1991-04-01

    A combined predictive and feedback control algorithm based on measurements of the concentration of glucose on-line has been developed to control fed-batch fermentations of Escherichia coli. The predictive control algorithm was based on the on-line calculation of glucose demand by the culture and plotting a linear regression to the next datum point to obtain a predicted glucose demand. This provided a predictive "coarse" control for the glucose-based nutrient feed. A direct feedback control using a proportional controller, based on glucose measurements every 2 min, fine-tuned the feed rate. These combined control schemes were used to maintain glucose concentrations in fed-batch fermentations as tight as 0.49 +/- 0.04 g/liter during growth of E. coli to high cell densities. PMID:2059049

  3. A predictive and feedback control algorithm maintains a constant glucose concentration in fed-batch fermentations.

    PubMed Central

    Kleman, G L; Chalmers, J J; Luli, G W; Strohl, W R

    1991-01-01

    A combined predictive and feedback control algorithm based on measurements of the concentration of glucose on-line has been developed to control fed-batch fermentations of Escherichia coli. The predictive control algorithm was based on the on-line calculation of glucose demand by the culture and plotting a linear regression to the next datum point to obtain a predicted glucose demand. This provided a predictive "coarse" control for the glucose-based nutrient feed. A direct feedback control using a proportional controller, based on glucose measurements every 2 min, fine-tuned the feed rate. These combined control schemes were used to maintain glucose concentrations in fed-batch fermentations as tight as 0.49 +/- 0.04 g/liter during growth of E. coli to high cell densities. PMID:2059049

  4. Adrenal Demedullation and Oxygen Supplementation Independently Increase Glucose-Stimulated Insulin Concentrations in Fetal Sheep With Intrauterine Growth Restriction.

    PubMed

    Macko, Antoni R; Yates, Dustin T; Chen, Xiaochuan; Shelton, Leslie A; Kelly, Amy C; Davis, Melissa A; Camacho, Leticia E; Anderson, Miranda J; Limesand, Sean W

    2016-05-01

    In pregnancies complicated by placental insufficiency and intrauterine growth restriction (IUGR), fetal glucose and oxygen concentrations are reduced, whereas plasma norepinephrine and epinephrine concentrations are elevated throughout the final third of gestation. Here we study the effects of chronic hypoxemia and hypercatecholaminemia on β-cell function in fetal sheep with placental insufficiency-induced IUGR that is produced by maternal hyperthermia. IUGR and control fetuses underwent a sham (intact) or bilateral adrenal demedullation (AD) surgical procedure at 0.65 gestation. As expected, AD-IUGR fetuses had lower norepinephrine concentrations than intact-IUGR fetuses despite being hypoxemic and hypoglycemic. Placental insufficiency reduced fetal weights, but the severity of IUGR was less with AD. Although basal plasma insulin concentrations were lower in intact-IUGR and AD-IUGR fetuses compared with intact-controls, glucose-stimulated insulin concentrations were greater in AD-IUGR fetuses compared with intact-IUGR fetuses. Interestingly, AD-controls had lower glucose- and arginine-stimulated insulin concentrations than intact-controls, but AD-IUGR and AD-control insulin responses were not different. To investigate chronic hypoxemia in the IUGR fetus, arterial oxygen tension was increased to normal levels by increasing the maternal inspired oxygen fraction. Oxygenation of IUGR fetuses enhanced glucose-stimulated insulin concentrations 3.3-fold in intact-IUGR and 1.7-fold in AD-IUGR fetuses but did not lower norepinephrine and epinephrine concentrations. Together these findings show that chronic hypoxemia and hypercatecholaminemia have distinct but complementary roles in the suppression of β-cell responsiveness in IUGR fetuses. PMID:26937714

  5. Surface contamination artificially elevates initial sweat mineral concentrations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During exercise in the heat, sweat is initially concentrated in minerals, but serial sweat samples appear more dilute. Possible causes include reduced dermal mineral concentrations or flushing of surface contamination. PURPOSE: To simultaneously sample mineral concentrations in transdermal fluid (T...

  6. Effects of clozapine administration on body weight, glucose tolerance, blood glucose concentrations, plasma lipids, and insulin in male C57BL/6 mice: A parallel controlled study

    PubMed Central

    Yuan, Hai-Yan; Liang, Hai-Xia; Liang, Guang-Rong; Zhang, Gui-Xiang; Li, Huan-De

    2008-01-01

    Background: Clozapine has been associated with metabolic adverse events (AEs) (eg, elevated body weight, blood glucose concentrations, cholesterol, triglycerides [TG]), all of which have deleterious effects on health and medication compliance. However, little focus has been directed toward finding a suitable experimental model to study the metabolic AEs associated with clozapine. Objective: The aim of this study was to assess the effects of clozapine administration for 28 days on body weight, glucose tolerance, blood glucose concentrations, plasma lipids, and insulin in C57BL/6 mice. Methods: C57BL/6 mice were grouped and treated with clozapine 2 or 10 mg/kg or vehicle intraperitoneally QD for 28 days. Body weight was assessed on days 0 (baseline), 7, 14, 21, and 28, and glucose tolerance, blood glucose concentrations, insulin (calculated by insulin resistance index [IRI]), and plasma lipids (including total cholesterol, TG, high-density lipoprotein cholesterol [HDL-C], and low-density lipoprotein cholesterol) were assessed on day 29. Results: Sixty 10-week-old, male C57BL/6 mice were included in the study and were divided into 3 groups (20 mice per group). The body weight significantly decreased in the clozapine 10-mg-treated group on days 14, 21, and 28 compared with the vehicle group (mean [SD] body weight: 21.61 [1.05] vs 22.79 [1.11], 22.53 [1.05] vs 24.17 [1.24], and 22.21 [1.07] vs 24.99 [1.39] g, respectively; all, P < 0.05). In the clozapine 10-mg/kg group, blood glucose concentrations significantly increased 0, 30, 60, and 120 minutes after glucose administration compared with the vehicle group (mean [SD]: 6.67 [1.25], 25.34 [5.85], 12.68 [3.39], and 7.52 [1.45] mmol/L, respectively, vs 4.61 [0.78], 21.54 [6.55], 11.46 [3.46], and 6.55 [1.42] mmol/L, respectively; all P < 0.05). The clozapine 10-mg/kg group also had significant increases in plasma insulin concentrations compared with the vehicle group (12.70 [5.27] vs 7.62 [4.54] μIU/mL; P < 0.05) and

  7. Predicting subcutaneous glucose concentration in humans: data-driven glucose modeling.

    PubMed

    Gani, Adiwinata; Gribok, Andrei V; Rajaraman, Srinivasan; Ward, W Kenneth; Reifman, Jaques

    2009-02-01

    The combination of predictive data-driven models with frequent glucose measurements may provide for an early warning of impending glucose excursions and proactive regulatory interventions for diabetes patients. However, from a modeling perspective, before the benefits of such a strategy can be attained, we must first be able to quantitatively characterize the behavior of the model coefficients as well as the model predictions as a function of prediction horizon. We need to determine if the model coefficients reflect viable physiologic dependencies of the individual glycemic measurements and whether the model is stable with respect to small changes in noise levels, leading to accurate near-future predictions with negligible time lag. We assessed the behavior of linear autoregressive data-driven models developed under three possible modeling scenarios, using continuous glucose measurements of nine subjects collected on a minute-by-minute basis for approximately 5 days. Simulation results indicated that stable and accurate models for near-future glycemic predictions (< 60 min) with clinically acceptable time lags are attained only when the raw glucose measurements are smoothed and the model coefficients are regularized. This study provides a starting point for further needed investigations before real-time deployment can be considered. PMID:19272928

  8. Measurement of tissue optical properties with optical coherence tomography: Implication for noninvasive blood glucose concentration monitoring

    NASA Astrophysics Data System (ADS)

    Larin, Kirill V.

    Approximately 14 million people in the USA and more than 140 million people worldwide suffer from diabetes mellitus. The current glucose sensing technique involves a finger puncture several times a day to obtain a droplet of blood for analysis. There have been enormous efforts by many scientific groups and companies to quantify glucose concentration noninvasively using different optical techniques. However, these techniques face limitations associated with low sensitivity, accuracy, and insufficient specificity of glucose concentrations over a physiological range. Optical coherence tomography (OCT), a new technology, is being applied for noninvasive imaging in tissues with high resolution. OCT utilizes sensitive detection of photons coherently scattered from tissue. The high resolution of this technique allows for exceptionally accurate measurement of tissue scattering from a specific layer of skin compared with other optical techniques and, therefore, may provide noninvasive and continuous monitoring of blood glucose concentration with high accuracy. In this dissertation work I experimentally and theoretically investigate feasibility of noninvasive, real-time, sensitive, and specific monitoring of blood glucose concentration using an OCT-based biosensor. The studies were performed in scattering media with stable optical properties (aqueous suspensions of polystyrene microspheres and milk), animals (New Zealand white rabbits and Yucatan micropigs), and normal subjects (during oral glucose tolerance tests). The results of these studies demonstrated: (1) capability of the OCT technique to detect changes in scattering coefficient with the accuracy of about 1.5%; (2) a sharp and linear decrease of the OCT signal slope in the dermis with the increase of blood glucose concentration; (3) the change in the OCT signal slope measured during bolus glucose injection experiments (characterized by a sharp increase of blood glucose concentration) is higher than that measured in

  9. Acute effects of concentric and eccentric exercise on glucose metabolism and interleukin-6 concentration in healthy males

    PubMed Central

    Krüsmann, PJ; Mersa, L; Eder, EM; Gatterer, H; Melmer, A; Ebenbichler, C; Burtscher, M

    2016-01-01

    Acute muscle-damaging eccentric exercise (EE) negatively affects glucose metabolism. On the other hand, long-term eccentric endurance exercise seems to result in equal or superior positive effects on glucose metabolism compared to concentric endurance exercise. However, it is not known if acute non-muscle-damaging EE will have the same positive effects on glucose metabolism as acute concentric exercise (CE). Interleukin-6 (IL-6) released from the exercising muscles may be involved in the acute adaptations of glucose metabolism after CE and non-muscle-damaging EE. The aim of this study was to assess acute effects of uphill walking (CE) and non-muscle-damaging downhill walking (EE) on glucose metabolism and IL-6 secretion. Seven sedentary non-smoking, healthy males participated in a crossover trial consisting of a 1 h uphill (CE) and a 1 h downhill (EE) walking block on a treadmill. Venous blood samples were drawn before (pre), directly after (acute) and 24 h after (post) exercise. An oral glucose tolerance test (OGTT) was performed before and 24 h after exercise. Glucose tolerance after 1 and 2 hours significantly improved 24 hours after CE (-10.12±3.22%: P=0.039; -13.40±8.24%: P=0.028). After EE only the 1-hour value was improved (-5.03±5.48%: P=0.043). Acute IL-6 concentration rose significantly after CE but not after EE. We conclude that both a single bout of CE and a single bout of non-muscle-damaging EE elicit positive changes in glucose tolerance even in young, healthy subjects. Our experiment indicates that the overall metabolic cost is a major trigger for acute adaptations of glucose tolerance after exercise, but only the IL-6 production during EE was closely related to changes in glycaemic control. PMID:27274108

  10. Acute effects of concentric and eccentric exercise on glucose metabolism and interleukin-6 concentration in healthy males.

    PubMed

    Philippe, M; Krüsmann, P J; Mersa, L; Eder, E M; Gatterer, H; Melmer, A; Ebenbichler, C; Burtscher, M

    2016-06-01

    Acute muscle-damaging eccentric exercise (EE) negatively affects glucose metabolism. On the other hand, long-term eccentric endurance exercise seems to result in equal or superior positive effects on glucose metabolism compared to concentric endurance exercise. However, it is not known if acute non-muscle-damaging EE will have the same positive effects on glucose metabolism as acute concentric exercise (CE). Interleukin-6 (IL-6) released from the exercising muscles may be involved in the acute adaptations of glucose metabolism after CE and non-muscle-damaging EE. The aim of this study was to assess acute effects of uphill walking (CE) and non-muscle-damaging downhill walking (EE) on glucose metabolism and IL-6 secretion. Seven sedentary non-smoking, healthy males participated in a crossover trial consisting of a 1 h uphill (CE) and a 1 h downhill (EE) walking block on a treadmill. Venous blood samples were drawn before (pre), directly after (acute) and 24 h after (post) exercise. An oral glucose tolerance test (OGTT) was performed before and 24 h after exercise. Glucose tolerance after 1 and 2 hours significantly improved 24 hours after CE (-10.12±3.22%: P=0.039; -13.40±8.24%: P=0.028). After EE only the 1-hour value was improved (-5.03±5.48%: P=0.043). Acute IL-6 concentration rose significantly after CE but not after EE. We conclude that both a single bout of CE and a single bout of non-muscle-damaging EE elicit positive changes in glucose tolerance even in young, healthy subjects. Our experiment indicates that the overall metabolic cost is a major trigger for acute adaptations of glucose tolerance after exercise, but only the IL-6 production during EE was closely related to changes in glycaemic control. PMID:27274108

  11. Study on non-invasive optical detection of the glucose concentration with scatters

    NASA Astrophysics Data System (ADS)

    Lin, Li-Han; Liao, Chia-Chi; Lo, Yu-Lung

    2015-03-01

    A new scheme to measure the glucose concentration with scatters is proposed for the detection of diabetics. In this study, the measuring technique based on the Stokes-Mueller polarimetry to solve the Mueller matrices of a complex sample containing circular birefringence and depolarization is developed. As a result, the circular birefringence and depolarization which relate to the concentrations of glucose and scattering events in turbid media can be inversely extracted.

  12. Salivary glucose concentration exhibits threshold kinetics in normal-weight, overweight, and obese children

    PubMed Central

    Hartman, Mor-Li; Goodson, J Max; Barake, Roula; Alsmadi, Osama; Al-Mutawa, Sabiha; Ariga, Jitendra; Soparkar, Pramod; Behbehani, Jawad; Behbehani, Kazem; Welty, Francine

    2015-01-01

    Background Metabolic syndrome in childhood predicts the development of cardiovascular disease and type 2 diabetes (T2D) in adulthood. Testing for features of metabolic syndrome, such as fasting plasma glucose concentration, requires blood sampling which can be difficult in children. Here we evaluated salivary glucose concentration as a surrogate measurement for plasma glucose concentration in 11-year-old US children. Methods Children from Portland, Maine, and Cambridge, Massachusetts, with a mean age of 10.6±0.2 years provided 6-hour fasting samples of both blood and whole saliva. Salivary glucose levels were measured with a high-sensitivity assay (sensitivity =0.002 mg/dL). Plasma glucose levels were determined by a commercial clinical laboratory. Blood pressure, salivary flow rate, height, and weight were also measured. Results Of the 65 children enrolled, there were two underweight children (3.1%), 30 normal-weight children (46.2%), 12 overweight children (18.4%), and 21 obese children (32.3%). The mean overall glucose concentrations were 0.11±0.02 mg/dL in saliva and 86.3±0.8 mg/dL in plasma, and these did not differ significantly by body–weight groups. By regression analysis, the plasma concentration equaled 13.5 times the saliva concentration, with a threshold level of 84.8 mg/dL. Salivary glucose values less than threshold plasma concentration were essentially zero. Diagnostic analysis indicated a positive predictive value of 50%, a negative predictive value of 90%, and a sensitivity and specificity both of approximately 75%. The salivary glucose concentration did not vary with saliva flow rate. Conclusion Taking into account the threshold response characteristics of the salivary glucose concentration response, these results suggest that testing salivary glucose levels may be useful as a screening assay for high fasting plasma glucose levels. The low false positive value is important to assure a low fraction of missed diagnoses. PMID:25565874

  13. A high concentration of glucose inhibits Tuber borchii mycelium growth: a biochemical investigation.

    PubMed

    Saltarelli, Roberta; Ceccaroli, Paola; Polidori, Emanuela; Citterio, Barbara; Vallorani, Luciana; Stocchi, Vilberto

    2003-01-01

    Tuber borchii mycelium (strain 1BO) is able to utilise glucose, fructose or mannitol in the culture medium as a carbohydrate source. Since sugars not only function as a metabolic resource and structural constituent of cells, but also act as important regulators of various processes, we investigated if high sugar concentrations could influence fungal growth and development. The studies performed in this paper revealed that fructose or mannitol used at high concentration (50 g l-1) in the culture medium do not influence the growth and the biochemical responses of fungus but the growth of T. borchii mycelium is subject to glucose repression. In experiments with a high glucose concentration (50 g l-1) and with 2-deoxyglucose, a non-metabolisable glucose analogue, the growth of T. borchii was halved with respect to the control (10 g l-1 of glucose). The morphological and biochemical analyses revealed that the hyphae were metabolically and functionally active, but the activity of mannitol dehydrogenase was reduced to one-third in the high glucose treatment. This is the first evidence of glucose repression of growth and activity in the ascomycetous ectomycorrhizal fungus T. borchii. PMID:12735246

  14. An integrated optical sensor for measuring glucose concentration

    NASA Astrophysics Data System (ADS)

    Liu, Y.; Hering, P.; Scully, M. O.

    1992-01-01

    We used an optical sensor combined with a Mach-Zehnder interferometric waveguide and optical fibers to measure slight changes of aqueous sugar concentrations. The merits of this sensor are simplicity, reliability, high sensitivity and continuous monitoring. The technique is based on the fact that the refractive index of sugar solution changes with the concentration of sugar. In the experiment, one arm of the interferometer is clad with glue and is thus isolated from the sugar solution. The other one is exposed to the sugar solution. A single mode fiber is directly glued onto the interferometric waveguide, to guide the light into the interferometer. If the concentration of sugar covering the waveguide changes, the phase of propagating light in the exposed arm will be changed, while the phase in the other arm is fixed. Hence the output intensity from the interferometer is directly related to the concentration of the sugar solution. The result of this experiment yields the relation between the sugar concentration and output signal. From 0% to 1% concentration of sugar solution, there is only a 1.4×10-3 refractive index difference. Two sets of experimental data have been obtained, showing a linear relation between the sugar concentration and the output signal from our sensor. This sensor could be used for continuous monitoring of blood sugar in the human body.

  15. Increasing Glucose Concentrations Interfere with Estimation of Electrolytes by Indirect Ion Selective Electrode Method.

    PubMed

    Goyal, Bela; Datta, Sudip Kumar; Mir, Altaf A; Ikkurthi, Saidaiah; Prasad, Rajendra; Pal, Arnab

    2016-04-01

    The estimation of electrolytes like sodium (Na(+)), potassium (K(+)) and chloride (Cl(-)) using direct and indirect ion-selective electrodes (ISE) is a routine laboratory practice. Interferents like proteins, triglycerides, drugs etc. are known to affect the results. The present study was designed to look into the effect of increasing glucose concentrations on estimation of Na(+), K(+) and Cl(-) by direct and indirect ISE. Pooled sera was mixed with glucose stock solution (20 g/dL) prepared in normal saline to obtain glucose concentrations ranging from ~100 to ~5000 mg/dL. Na(+), K(+) and Cl(-) levels were estimated by direct and indirect ISE analyzers and results were statistically analysed using ANOVA and Pearson's correlation. Similar experiment was also performed in 24 h urine sample from healthy subjects. Significant difference was observed between Na(+) and Cl(-) measurements by direct and indirect ISE, with indirect ISE values being consistently higher than direct ISE. Besides this, significant difference was observed amongst Na(+) and Cl(-) values from baseline values obtained by indirect ISE at glucose concentrations ≥2486 mg/dL. However, no such difference was observed with direct ISE. Na(+) and Cl(-) estimation by indirect ISE showed significant negative correlation with glucose concentration, more so, above ~2000 mg/dL. K(+), however, showed no significant difference with varying glucose. Similar results were observed in 24 h urine samples with a significant difference observed amongst Na(+) and Cl(-) values at ≥2104 mg/dL glucose. Thus we conclude that high glucose concentrations interfere significantly in estimation of Na(+) and Cl(-) by indirect ISE in serum as well as urine. PMID:27069331

  16. Photoacoustic determination of glucose concentration in whole blood by a near-infrared laser diode

    NASA Astrophysics Data System (ADS)

    Zhao, Zuomin; Myllylae, Risto A.

    2001-06-01

    The near-infrared photoacoustic technique is recognized as a potential method for the non-invasive determination of human glucose, because near-infrared light can incident a few millimeters into human tissue, where it produces an acoustic wave capable of carrying information about the composition of the tissue. This paper demonstrates a photoacoustic glucose measurement in a blood sample as a step toward a non-invasive measurement. The experimental apparatus consists of a near-infrared laser diode operating with 4 micro joules pulse energy at 905 nm, a roller pump connected to a silicon plastic tube and a cuvette for circulating the blood sample. In addition, the apparatus comprises a PZT piezoelectric transducer integrated with a battery-powered preamplifier to receive the photoacoustic signal. During the experiment, a glucose solution is mixed into a human blood sample to change its concentration. Although the absorption coefficient of glucose is much smaller than that of blood in the near-infrared region, the osmotic and hydrophilic properties of glucose decrease the reduced scattering coefficient of blood caused by the dissolved glucose surrounding the blood cells. This changes the distribution of the absorbed optical energy in blood, which, in turn, produces a change in the photoacoustic signal. Our experiment demonstrates that signal amplitudes in fresh and stored blood samples in crease about 7% and 10%, respectively, when the glucose concentration reaches the upper limit of the physiological region (500 mg/dl).

  17. Dynamic modeling of the hydrogel molecular filter in a metamaterial biosensing system for glucose concentration estimation.

    PubMed

    Teutsch, T; Mesch, M; Giessen, H; Tarin, C

    2014-01-01

    We present a novel concept for ophthalmic glucose sensing using a biosensing system that consists of plasmonic dipole metamaterial covered by a layer of functionalized hydrogel. The metamaterial together with the hydrogel can be integrated into a contact lens. This optical sensor changes its properties such as reflectivity upon the ambient glucose concentration, which allows in situ measurements in the eye. The functionalization of the sensor with hydrogel allows for a glucose-specific detection, providing both selectivity and sensitivity. As a result of the presented work we derive a dynamic model of the hydrogel that can be used for further simulation studies. PMID:25570394

  18. ELEVATED METHYLMALOIC ACID CONCENTRATIONS ARE COMMON AMONG ELDERLY AMERICANS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To describe serum methylmalonic acid (MMA) concentrations of elderly Americans and examine relations between serum MMA and other factors, we used surplus sera collected from elderly (n=1,145) and young-adult (n=1,026) participants in Phase 2 of the third National Health and Nutrition Examination Sur...

  19. INTERCOMPARISON OF ATMOSPHERIC NITRIC ACID MEASUREMENTS AT ELEVATED AMBIENT CONCENTRATIONS

    EPA Science Inventory

    Several methods for measurement of ambient HNO3 were compared over a 9-day period during the Carbonaceous Species Methods Comparison Study at Glendora, CA, in August 1986. ourly averaged HNO3 concentrations were in the range 0.5-25 ppbv, with hourly maxima each day in excess of 1...

  20. Whey protein concentrate storage at elevated temperature and humidity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dairy processors are finding new export markets for whey protein concentrate (WPC), a byproduct of cheesemaking, but they need to know if full-sized bags of this powder will withstand high temperature and relative humidity (RH) levels during unrefrigerated storage under tropical conditions. To answ...

  1. Vasopressin activates Akt/mTOR pathway in smooth muscle cells cultured in high glucose concentration

    SciTech Connect

    Montes, Daniela K.; Brenet, Marianne; Muñoz, Vanessa C.; Burgos, Patricia V.; Villanueva, Carolina I.; Figueroa, Carlos D.; González, Carlos B.

    2013-11-29

    Highlights: •AVP induces mTOR phosphorylation in A-10 cells cultured in high glucose concentration. •The mTOR phosphorylation is mediated by the PI3K/Akt pathway activation. •The AVP-induced mTOR phosphorylation inhibited autophagy and stimulated cell proliferation. -- Abstract: Mammalian target of rapamycin (mTOR) complex is a key regulator of autophagy, cell growth and proliferation. Here, we studied the effects of arginine vasopressin (AVP) on mTOR activation in vascular smooth muscle cells cultured in high glucose concentration. AVP induced the mTOR phosphorylation in A-10 cells grown in high glucose, in contrast to cells cultured in normal glucose; wherein, only basal phosphorylation was observed. The AVP-induced mTOR phosphorylation was inhibited by a PI3K inhibitor. Moreover, the AVP-induced mTOR activation inhibited autophagy and increased thymidine incorporation in cells grown in high glucose. This increase was abolished by rapamycin which inhibits the mTORC1 complex formation. Our results suggest that AVP stimulates mTOR phosphorylation by activating the PI3K/Akt signaling pathway and, subsequently, inhibits autophagy and raises cell proliferation in A-10 cells maintained in high glucose concentration.

  2. Impact of Admission Glucose on Non-Diabetic Patients with ST-Segment Elevation Myocardial Infarction Treated with Percutaneous Coronary Intervention: A Meta-Analysis

    PubMed Central

    Hao, Zhen-Xuan; Liu, Yang; Wang, Dan-Li; Han, Wen-Jie; Wu, Lei; Liu, Heng-Liang

    2016-01-01

    Background Impaired admission glucose (AG) is thought to significantly increase the risk of both early and late death with ST-segment elevation myocardial infarction (STEMI), especially for non-diabetic patients. However, several earlier studies contradict these relationships. Through our meta-analysis, we aimed to evaluate such a relation between impaired AG, the risk of death and STEMI. Methods We accessed PubMed, EMBASE, Web of Science, and the Cochrane Library and systematically searched their databases to identify all related prospective cohort studies. The relative risks (RRs) with their 95% confidence interval (CI) were pooled quantitatively. Results The pooled, unadjusted relative risks of early outcome events indicated that patients who had glucose concentrations ≥ the range of 6.1-11.1 mmol/L, had a 4.38-fold (95% CI, 3.23-5.94) higher early mortality. For late outcome events, the pooled unadjusted RR indicated patients who had glucose concentrations ≥ the range 7.8-11.1 mmol/L, and had a 2.69-fold (95% CI, 2.16-3.34) higher late mortality based on full participants, whereas patients had a 1.65-fold (95% CI, 1.33-2.04) higher late mortality based on based on in-hospital or 30-day survivors. Conclusions In conclusion, the present meta-analysis demonstrated that impaired admission glucose may be an effective prognostic marker for significantly increased risk of early death. Regarding the long-term outcomes based on full population or early survival, high admission glucose also has a distinct but poorer prognostic impact on long-term mortality than early mortality. PMID:27122950

  3. Real-time estimation of plasma insulin concentration from continuous glucose monitor measurements.

    PubMed

    de Pereda, Diego; Romero-Vivo, Sergio; Ricarte, Beatriz; Rossetti, Paolo; Ampudia-Blasco, Francisco Javier; Bondia, Jorge

    2016-01-01

    Continuous glucose monitors can measure interstitial glucose concentration in real time for closed-loop glucose control systems, known as artificial pancreas. These control systems use an insulin feedback to maintain plasma glucose concentration within a narrow and safe range, and thus to avoid health complications. As it is not possible to measure plasma insulin concentration in real time, insulin models have been used in literature to estimate them. Nevertheless, the significant inter- and intra-patient variability of insulin absorption jeopardizes the accuracy of these estimations. In order to reduce these limitations, our objective is to perform a real-time estimation of plasma insulin concentration from continuous glucose monitoring (CGM). Hovorka's glucose-insulin model has been incorporated in an extended Kalman filter in which different selected time-variant model parameters have been considered as extended states. The observability of the original Hovorka's model and of several extended models has been evaluated by their Lie derivatives. We have evaluated this methodology with an in-silico study with 100 patients with Type 1 diabetes during 25 h. Furthermore, it has been also validated using clinical data from 12 insulin pump patients with Type 1 diabetes who underwent four mixed meal studies. Real-time insulin estimations have been compared to plasma insulin measurements to assess performance showing the validity of the methodology here used in comparison with that formerly used for insulin models. Hence, real-time estimations for plasma insulin concentration based on subcutaneous glucose monitoring can be beneficial for increasing the efficiency of control algorithms for the artificial pancreas. PMID:26343364

  4. In vitro study of PET tumor tracers at normal and elevated media glucose levels

    SciTech Connect

    Torizuka, T.; Clavo, A.C.; Wahl, R.L.

    1996-05-01

    FDG uptake in tumors is decreased by hyperglycemia. Little is known about the effect of hyperglycemia on non-FDG PET tracer uptake in tumors. This study was designed to determine if PET tumor tracers are affected by chronic exposure of tumor cells to high media glucose levels. Human ovarian adenocarcinoma (HTB77IP3) cells normally grown at 100 mg/dl of glucose were grown in media with 100 or 300 mg/dl of glucose. At 20, 26 and 38 days after initial culture (6-7 days after subculture), uptakes of 3H-labeled FDG, Thymidine (Thy), Methionine (Met) and Leucine (Leu) into the cells (n=4) were determined at the same glucose level as growth media. Tracer uptake per 1 million cells was measured after a 60 min uptake period. Presented are percentage of tracer uptake of cells grown at 300 mg/dl of glucose relative to uptake of cells grown at 100 mg/dl of glucose (mean {plus_minus} SD of 20, 26, and 38 days culture). Paired t-tests were used to compare tracer uptake of cells grown and assayed at both glucose levels. P values <0.05 were considered significant. FDG uptake of cells grown and assayed at 300 mg/dl of glucose was significantly decreased, compared with uptake of cells grown and assayed at 100 mg/dl of glucose. By contrast, uptake of Thy, Met and Leu were not different between cells grown and assayed at 100 or 300 mg/dl of glucose. These results indicate that tumor uptake of Thy, Met and Leu do not depend on media glucose level and suggest that these tracers labeled with C-11 are suitable for hyperglycemic patients, in whom tumor FDG uptake is expected to be impaired.

  5. The Association between HbA1c, Fasting Glucose, 1-Hour Glucose and 2-Hour Glucose during an Oral Glucose Tolerance Test and Cardiovascular Disease in Individuals with Elevated Risk for Diabetes

    PubMed Central

    Lind, Marcus; Tuomilehto, Jaakko; Uusitupa, Matti; Nerman, Olle; Eriksson, Johan; Ilanne-Parikka, Pirjo; Keinänen-Kiukaanniemi, Sirkka; Peltonen, Markku; Pivodic, Aldina; Lindström, Jaana

    2014-01-01

    Objective To determine the association between HbA1c, fasting plasma glucose (FPG), 1-hour (1 hPG) and 2-hour (2 hPG) glucose after an oral glucose tolerance test (OGTT) and cardiovascular disease in individuals with elevated risk for diabetes. Design We studied the relationship between baseline, updated mean and updated (last) value of HbA1c, FPG, 1 hPG and 2 hPG after an oral 75 g glucose tolerance test (OGTT) and acute CVD events in 504 individuals with impaired glucose tolerance (IGT) at baseline enrolled in the Finnish Diabetes Prevention Study. Setting Follow-up of clinical trial. Participants 504 individuals with IGT were followed with yearly evaluations with OGTT, FPG and HbA1c. Main Outcome Measure Relative risk of CVD. Results Over a median follow-up of 9.0 years 34 (6.7%) participants had a CVD event, which increased to 52 (10.3%) over a median follow-up of 13.0 years when including events that occurred among participants following a diagnosis of diabetes. Updated mean HbA1c, 1 hPG and 2 hPG, HR per 1 unit SD of 1.57 (95% CI 1.16 to 2.11), p = 0.0032, 1.51 (1.03 to 2.23), p = 0.036 and 1.60 (1.10 to 2.34), p = 0.014, respectively, but not FPG (p = 0.11), were related to CVD. In analyses of the last value prior to the CVD event the same three glycaemic measurements were associated with the CVD events, with HRs per 1 unit SD of 1.45 (1.06 to 1.98), p = 0.020, 1.55 (1.04 to 2.29), p = 0.030 and 2.19 (1.51 to 3.18), p<0.0001, respectively but only 2 hPG remained significant in pairwise comparisons. Including the follow-up period after diabetes onset updated 2 hPG (p = 0.003) but not updated mean HbA1c (p = 0.08) was related to CVD. Conclusions and Relevance Current 2 hPG level in people with IGT is associated with increased risk of CVD. This supports its use in screening for prediabetes and monitoring glycaemic levels of people with prediabetes. PMID:25285769

  6. Increased accumulation of carbohydrates and decreased photosynthetic gene transcript levels in wheat grown at an elevated CO{sub 2} concentration in the field

    SciTech Connect

    Nie, G.; Hendrix, D.L.; Webber, A.N.

    1995-07-01

    Repression of photosynthetic genes by increased soluble carbohydrate concentrations may explain acclimation of photosynthesis to elevated CO{sub 2} concentration. This hypothesis was examined in a field crop of spring wheat (Triticum aestivum L.) grown at both ambient (approximately 360 {mu}mol{sup -1}) and elevated (550 {mu}mol mol{sup -1}) atmospheric CO{sub 2} concentrations using free-air CO{sub 2} enrichment at Maricopa, Arizona. The correspondence of steady-state levels of mRNA transcripts (coding for the 83-kD photosystem 1 apoprotein, sedoheptulose-1,7-bisphosphatase, phosphoribulokinase, phosphoglcerodkinase, and the large and small subunits of ribulose-1,5-bisphosphate carboxylase/oxygenase) with leaf carbohydrate concentrations (glucose-6-phosphate, glucose, fructose, sucrose, fructans, and starch) was examined at different stages of crop and leaf development and through the diurnal cycle. Overall only a weak correspondence between increased soluble carbohydrate concentrations and decreased levels for nuclear gene transcripts was found. The difference in soluble carbohydrate concentration between leaves grown at elevated and current ambient CO{sub 2} concentrations diminished with crop development, whereas the difference in transcript levels increased. In the flag leaf, soluble carbohydrate concentrations declined markedly with the onset of grain filling; yet transcript levels also declined. The results suggest that, many other factors modified its significance in this field wheat crop. 52 refs., 8 figs.

  7. Exploration of noninvasive determination of blood glucose concentration by using photoacoustic technique

    NASA Astrophysics Data System (ADS)

    Ren, Zhong; Liu, Guodong; Liu, Ying; Huang, Zhen

    2013-09-01

    Photoacoustic (PA) noninvasive detection has become a research hotspot of measuring blood glucose concentration (BGC) in recent years. This novel method overcomes greatly the scattering light interference problem must be faced in near infrared (NIR) spectroscopy. A PA based BGC measurement set-up was established, in which a Q switched Nd: YAG pumped optical parametric oscillator (OPO) pulsed laser is used as the excitation source and lateral detection model was used to detetct the PA signals of glucose. To validate the profile model of real time PA signal, determine the characteristic wavelengths of glucose, a series of vitro experiments of glucose aqueous solutions were perfromed. Several wavelengths were preliminarily determined as the characteristic wavelengths via the peak-to-peak values difference. The prediction concentration model was established via least square fitting algorithm between PA peak-to-peak values with their different concentrations. The experimental results demonstrated that the PA profile of glucose is consistent with PA meachnism and the root-mean-squre error (RMSE) of prediction concentration can reach 0.77mmol/L. Therefore, this PA based set-up and scheme has the potential value in the BGC monitoring research.

  8. In vitro measurements of physiological glucose concentrations in biological fluids using mid-infrared light

    PubMed Central

    Liakat, Sabbir; Bors, Kevin A.; Huang, Tzu-Yung; Michel, Anna P. M.; Zanghi, Eric; Gmachl, Claire F.

    2013-01-01

    Mid-infrared transmission spectroscopy using broadband mid-infrared or Quantum Cascade laser sources is used to predict glucose concentrations of aqueous and serum solutions containing physiologically relevant amounts of glucose (50-400 mg/dL). We employ partial least squares regression to generate a calibration model using a subset of the spectra taken and to predict concentrations from new spectra. Clinically accurate measurements with respect to a Clarke error grid were made for concentrations as low as 30 mg/dL, regardless of background solvent. These results are an important and encouraging step in the work towards developing a noninvasive in vivo glucose sensor in the mid-infrared. PMID:23847734

  9. An in-line photonic biosensor for monitoring of glucose concentrations.

    PubMed

    Al-Halhouli, Ala'aldeen; Demming, Stefanie; Alahmad, Laila; LIobera, Andreu; Büttgenbach, Stephanus

    2014-01-01

    This paper presents two PDMS photonic biosensor designs that can be used for continuous monitoring of glucose concentrations. The first design, the internally immobilized sensor, consists of a reactor chamber, micro-lenses and self-alignment structures for fiber optics positioning. This sensor design allows optical detection of glucose concentrations under continuous glucose flow conditions of 33 µL/h based on internal co-immobilization of glucose oxidase (GOX) and horseradish peroxidase (HRP) on the internal PDMS surface of the reactor chamber. For this design, two co-immobilization methods, the simple adsorption and the covalent binding (PEG) methods were tested. Experiments showed successful results when using the covalent binding (PEG) method, where glucose concentrations up to 5 mM with a coefficient of determination (R2) of 0.99 and a limit of detection of 0.26 mM are detectable. The second design is a modified version of the internally immobilized sensor, where a microbead chamber and a beads filling channel are integrated into the sensor. This modification enabled external co-immobilization of enzymes covalently onto functionalized silica microbeads and allows binding a huge amount of HRP and GOX enzymes on the microbeads surfaces which increases the interaction area between immobilized enzymes and the analyte. This has a positive effect on the amount and rate of chemical reactions taking place inside the chamber. The sensor was tested under continuous glucose flow conditions and was found to be able to detect glucose concentrations up to 10 mM with R2 of 0.98 and a limit of detection of 0.7 mM. Such results are very promising for the application in photonic LOC systems used for online analysis. PMID:25157552

  10. An In-Line Photonic Biosensor for Monitoring of Glucose Concentrations

    PubMed Central

    Al-Halhouli, Ala'aldeen; Demming, Stefanie; Alahmad, Laila; LIobera, Andreu; Büttgenbach, Stephanus

    2014-01-01

    This paper presents two PDMS photonic biosensor designs that can be used for continuous monitoring of glucose concentrations. The first design, the internally immobilized sensor, consists of a reactor chamber, micro-lenses and self-alignment structures for fiber optics positioning. This sensor design allows optical detection of glucose concentrations under continuous glucose flow conditions of 33 μL/h based on internal co-immobilization of glucose oxidase (GOX) and horseradish peroxidase (HRP) on the internal PDMS surface of the reactor chamber. For this design, two co-immobilization methods, the simple adsorption and the covalent binding (PEG) methods were tested. Experiments showed successful results when using the covalent binding (PEG) method, where glucose concentrations up to 5 mM with a coefficient of determination (R2) of 0.99 and a limit of detection of 0.26 mM are detectable. The second design is a modified version of the internally immobilized sensor, where a microbead chamber and a beads filling channel are integrated into the sensor. This modification enabled external co-immobilization of enzymes covalently onto functionalized silica microbeads and allows binding a huge amount of HRP and GOX enzymes on the microbeads surfaces which increases the interaction area between immobilized enzymes and the analyte. This has a positive effect on the amount and rate of chemical reactions taking place inside the chamber. The sensor was tested under continuous glucose flow conditions and was found to be able to detect glucose concentrations up to 10 mM with R2 of 0.98 and a limit of detection of 0.7 mM. Such results are very promising for the application in photonic LOC systems used for online analysis. PMID:25157552

  11. Post-Bariatric Surgery Changes in Quinolinic and Xanthurenic Acid Concentrations Are Associated with Glucose Homeostasis

    PubMed Central

    Pigeyre, Marie; Caiazzo, Robert; Raverdy, Violeta; Verkindt, Hélène; Leloire, Audrey; Guillemin, Gilles J.; Yengo, Loïc; Allorge, Delphine; Froguel, Philippe; Pattou, François

    2016-01-01

    Background An increase of plasma kynurenine concentrations, potentially bioactive metabolites of tryptophan, was found in subjects with obesity, resulting from low-grade inflammation of the white adipose tissue. Bariatric surgery decreases low-grade inflammation associated with obesity and improves glucose control. Objective Our goal was to determine the concentrations of all kynurenine metabolites after bariatric surgery and whether they were correlated with glucose control improvement. Design Kynurenine metabolite concentrations, analysed by liquid or gas chromatography coupled with tandem mass spectrometry, circulating inflammatory markers, metabolic traits, and BMI were measured before and one year after bariatric surgery in 44 normoglycemic and 47 diabetic women with obesity. Associations between changes in kynurenine metabolites concentrations and in glucose control and metabolic traits were analysed between baseline and twelve months after surgery. Results Tryptophan and kynurenine metabolite concentrations were significantly decreased one year after bariatric surgery and were correlated with the decrease of the usCRP in both groups. Among all the kynurenine metabolites evaluated, only quinolinic acid and xanthurenic acid were significantly associated with glucose control improvement. The one year delta of quinolinic acid concentrations was negatively associated with the delta of fasting glucose (p = 0.019) and HbA1c (p = 0.014), whereas the delta of xanthurenic acid was positively associated with the delta of insulin sensitivity index (p = 0.0018). Conclusion Bariatric surgery has induced a global down-regulation of kynurenine metabolites, associated with weight loss. Our results suggest that, since kynurenine monoxygenase diverts the kynurenine pathway toward the synthesis of xanthurenic acid, its inhibition may also contribute to glucose homeostasis. PMID:27327770

  12. Differential Responses of Plasma Adropin Concentrations To Dietary Glucose or Fructose Consumption In Humans.

    PubMed

    Butler, Andrew A; St-Onge, Marie-Pierre; Siebert, Emily A; Medici, Valentina; Stanhope, Kimber L; Havel, Peter J

    2015-01-01

    Adropin is a peptide hormone encoded by the Energy Homeostasis Associated (ENHO) gene whose physiological role in humans remains incompletely defined. Here we investigated the impact of dietary interventions that affect systemic glucose and lipid metabolism on plasma adropin concentrations in humans. Consumption of glucose or fructose as 25% of daily energy requirements (E) differentially affected plasma adropin concentrations (P < 0.005) irrespective of duration, sex or age. Glucose consumption reduced plasma adropin from 3.55 ± 0.26 to 3.28 ± 0.23 ng/ml (N = 42). Fructose consumption increased plasma adropin from 3.63 ± 0.29 to 3.93 ± 0.34 ng/ml (N = 45). Consumption of high fructose corn syrup (HFCS) as 25% E had no effect (3.43 ± 0.32 versus 3.39 ± 0.24 ng/ml, N = 26). Overall, the effect of glucose, HFCS and fructose on circulating adropin concentrations were similar to those observed on postprandial plasma triglyceride concentrations. Furthermore, increases in plasma adropin levels with fructose intake were most robust in individuals exhibiting hypertriglyceridemia. Individuals with low plasma adropin concentrations also exhibited rapid increases in plasma levels following consumption of breakfasts supplemented with lipids. These are the first results linking plasma adropin levels with dietary sugar intake in humans, with the impact of fructose consumption linked to systemic triglyceride metabolism. In addition, dietary fat intake may also increase circulating adropin concentrations. PMID:26435060

  13. Elevated atmospheric C02 concentration and temperature across an urban-rural transect

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The heat island effect and the high use of fossil fuels in large city centers are well documented, but by how much fossil fuel consumption is elevating atmospheric CO2 concentrations and whether elevations in both atmospheric CO2 and air temperature are consistent from year to year are less well kno...

  14. Genotypic Variation in Soybean Molecular Responses to Elevated Carbon Dioxide Concentration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A critical step in maximizing crop yield in a future of elevated atmospheric carbon dioxide concentration ([CO2]) is identifying genotypic variability in response to elevated [CO2] and understanding the molecular basis for the variation. We compared photosynthesis, leaf metabolites and global gene e...

  15. Elevated Glucose Oxidation, Reduced Insulin Secretion, and a Fatty Heart May Be Protective Adaptions in Ischemic CAD

    PubMed Central

    Hannukainen, J. C.; Lautamäki, R.; Mari, A.; Pärkkä, J. P.; Bucci, M.; Guzzardi, M. A.; Kajander, S.; Tuokkola, T.; Knuuti, J.

    2016-01-01

    Background: Insulin resistance, β-cell dysfunction, and ectopic fat deposition have been implicated in the pathogenesis of coronary artery disease (CAD) and type 2 diabetes, which is common in CAD patients. We investigated whether CAD is an independent predictor of these metabolic abnormalities and whether this interaction is influenced by superimposed myocardial ischemia. Methods and Results: We studied CAD patients with (n = 8) and without (n = 14) myocardial ischemia and eight non-CAD controls. Insulin sensitivity and secretion and substrate oxidation were measured during fasting and oral glucose tolerance testing. We used magnetic resonance imaging/spectroscopy, positron emission and computerized tomography to characterize CAD, cardiac function, pericardial and abdominal adipose tissue, and myocardial, liver, and pancreatic triglyceride contents. Ischemic CAD was characterized by elevated oxidative glucose metabolism and a proportional decline in β-cell insulin secretion and reduction in lipid oxidation. Cardiac function was preserved in CAD groups, whereas cardiac fat depots were elevated in ischemic CAD compared to non-CAD subjects. Liver and pancreatic fat contents were similar in all groups and related with surrounding adipose masses or systemic insulin sensitivity. Conclusions: In ischemic CAD patients, glucose oxidation is enhanced and correlates inversely with insulin secretion. This can be seen as a mechanism to prevent glucose lowering because glucose is required in oxygen-deprived tissues. On the other hand, the accumulation of cardiac triglycerides may be a physiological adaptation to the limited fatty acid oxidative capacity. Our results underscore the urgent need of clinical trials that define the optimal/safest glycemic range in situations of myocardial ischemia. PMID:27045985

  16. Induction of fatty acid synthase and S14 gene expression by glucose, xylitol and dihydroxyacetone in cultured rat hepatocytes is closely correlated with glucose 6-phosphate concentrations.

    PubMed Central

    Mourrieras, F; Foufelle, F; Foretz, M; Morin, J; Bouche, S; Ferre, P

    1997-01-01

    It is now well established that the transcription of several genes belonging to the glycolytic and lipogenic pathway is stimulated in the presence of a high glucose concentration in adipocytes and hepatocytes. We have previously proposed that glucose 6-phosphate could be the signal metabolite that transduces the glucose effect. This proposal has recently been challenged and both an intermediate of the pentose phosphate pathway, xylulose 5-phosphate, and metabolites of the later part of glycolysis (3-phosphoglycerate and phosphoenolpyruvate) have been proposed. To discriminate between these possibilities, we have measured concomitantly, in primary cultures of adult rat hepatocytes, the expression of the fatty acid synthase (FAS) and S14 genes and the concentration of glucose metabolites. We have used various substrates entering at different steps of the glycolytic pathway (glucose, dihydroxyacetone) and the pentose phosphate pathway (xylitol). When compared with 5 mM glucose, 25 mM glucose induces a marked increase in both S14 and FAS gene expression, detectable as early as 2 h and peaking at 6 h. Increasing concentrations (1-5 mM) of xylitol and dihydroxyacetone in the presence of 5 mM glucose are also able to induce S14 and FAS gene expression progressively. Among the various glucose metabolites measured, glucose 6-phosphate, in contrast with xylulose 5-phosphate and metabolites of the lower part of glycolysis, is the only one that shows a clear-cut parallelism between its concentration and the degree of S14 and FAS gene expression. We conclude that glucose 6-phosphate is the most likely signal metabolite for the glucose-induced transcription of this group of genes. PMID:9291103

  17. Determination of Blood Glucose Concentration by Using Wavelet Transform and Neural Networks

    PubMed Central

    Ashok, Vajravelu; Kumar, Nirmal

    2013-01-01

    Background: Early and non-invasive determination of blood glucose level is of great importance. We aimed to present a new technique to accurately infer the blood glucose concentration in peripheral blood flow using non-invasive optical monitoring system. Methods: The data for the research were obtained from 900 individuals. Of them, 750 people had diabetes mellitus (DM). The system was designed using a helium neon laser source of 632.8 nm wavelength with 5mW power, photo detectors and digital storage oscilloscope. The laser beam was directed through a single optical fiber to the index finger and the scattered beams were collected by the photo detectors placed circumferentially to the transmitting fiber. The received signals were filtered using band pass filter and finally sent to a digital storage oscilloscope. These signals were then decomposed into approximation and detail coefficients using modified Haar Wavelet Transform. Back propagation neural and radial basis functions were employed for the prediction of blood glucose concentration. Results: The data of 450 patients were randomly used for training, 225 for testing and the rest for validation. The data showed that outputs from radial basis function were nearer to the clinical value. Significant variations could be seen from signals obtained from patients with DM and those without DM. Conclusion: The proposed non-invasive optical glucose monitoring system is able to predict the glucose concentration by proving that there is a definite variation in hematological distribution between patients with DM and those without DM. PMID:23645958

  18. Photoacoustic measurement for glucose solution concentration based on tunable pulsed laser induced ultrasound

    NASA Astrophysics Data System (ADS)

    Ren, Zhong; Liu, Guodong; Huang, Zhen; Zhao, Dengji

    2012-12-01

    Noninvasive measurement of blood glucose concentration (BGC) has become a research hotspot. BGC measurement based on photoacoustic spectroscopy (PAS) was employed to detect the photoacoustic (PA) signal of blood glucose due to the advantages of avoiding the disturbance of optical scattering. In this paper, a set of custom-built BGC measurement system based on tunable optical parametric oscillator (OPO) pulsed laser and ultrasonic transducer was established to test the PA response effect of the glucose solution. In the experiments, we successfully acquired the time resolved PA signals of distilled water and glucose aqueous solution, and the PA peak-to-peak values(PPV) were gotten under the condition of excitated pulsed laser with changed wavelength from 1340nm to 2200nm by increasing interval of 10nm, the optimal characteristic wavelengths of distilled water and glucose solution were determined. Finally, to get the concentration prediction error, we used the linear fitting of ordinary least square (OLS) algorithm to fit the PPV of 1510nm, and we got the predicted concentration error was about 0.69mmol/L via the fitted linear equation. So, this system and scheme have some values in the research of noninvasive BGC measurement.

  19. Measurement of glucose concentration in turbid media by the polarization state of backscattered laser light

    NASA Astrophysics Data System (ADS)

    Kafidova, Galina A.; Aksenov, Evgenii T.; Petrov, Victor M.

    2013-06-01

    Biological tissues, including human skin, are complex objects for optical measurements. Because of its multi-component structure, they are characterized by a combined response to various dynamic changes, both inside and outside of the biological object. Change of glucose concentration in the blood leads to a number of processes, which affect the light scattering properties of the skin and subcutaneous layers, herewith scattering coefficient and the polarization of the scattered light vary. The possibility of non-invasive blood glucose detection by parameters of backscattered laser light was experimentally demonstrated. Degree of polarization of light scattered by human skin and model objects was registered and dependence of the polarization state of backscattered radiation on the glucose concentration in the human blood was shown. A laboratory model of a differential polarimeter, which allows registering the parameters of the polarized radiation scattered by human skin and glucose containing models was developed. Using the developed model, model and full-scale experiments were conducted. In the model experiments, the light scattered in the forward and backwards direction by the following model objects: a 20% solution of milk and a 50% solution of whole human blood was investigated. The ability of the developed sensor to noninvasively detect the concentration of glucose in the blood was demonstrated.

  20. Eucalyptus leaf extract suppresses the postprandial elevation of portal, cardiac and peripheral fructose concentrations after sucrose ingestion in rats.

    PubMed

    Sugimoto, Keiichiro; Hosotani, Tetsuro; Kawasaki, Takahiro; Nakagawa, Kazuya; Hayashi, Shuichi; Nakano, Yoshihisa; Inui, Hiroshi; Yamanouchi, Toshikazu

    2010-05-01

    Overintake of sucrose or fructose induces adiposity. Fructose undergoes a strong Maillard reaction, which worsens diabetic complications. To determine whether Eucalyptus globulus leaf extract (ELE) suppresses the postprandial elevation of serum fructose concentrations (SFCs) in the portal, cardiac, and peripheral blood after sucrose ingestion, we performed gas chromatography/mass spectrometry (GC/MS) and measured SFC without any interference by contaminating glucose in the samples. Fasting Wistar rats were orally administered water (control group) or ELE (ELE group) before sucrose ingestion. Blood was collected from the portal vein, heart, and tail. The increase in the SFCs in the portal and cardiac samples 30 min after sucrose ingestion was lower in the ELE group than in the control group. The coefficient of correlation between the SFCs in the portal and cardiac samples was 0.825. The peripheral SFC in the control group progressively increased and was 146 micromol/L at 60 min. This increase was significantly lower in the ELE group. In contrast, the serum glucose concentrations in the 2 groups were similar. ELE suppressed postprandial hyperfructosemia in the portal, cardiac, and peripheral circulations. ELE may counteract glycation caused by high blood fructose concentrations induced by the consumption of fructose-containing foods or drinks. PMID:20490315

  1. Substrate inhibition kinetics of Saccharomyces cerevisiae in fed-batch cultures operated at constant glucose and maltose concentration levels.

    PubMed

    Papagianni, M; Boonpooh, Y; Mattey, M; Kristiansen, B

    2007-04-01

    Fed-batch culture is the mode of operation of choice in industrial baker's yeast fermentation. The particular mode of culture, operated at stable glucose and maltose concentration levels, was employed in this work in order to estimate important kinetic parameters in a process mostly described in the literature as batch or continuous culture. This way, the effects of a continuously falling sugar level during a batch process were avoided and therefore the effects of various (stable) sugar levels on growth kinetics were evaluated. Comparing the kinetics of growth and the inhibition by the substrate in cultures grown on glucose, which is the preferential sugar source for Saccharomyces cerevisiae, and maltose, the most common sugar source in industrial media for baker's yeast production, a milder inhibition effect by the substrate in maltose-grown cells was observed, as well as a higher yield coefficient. The observed sugar inhibition effect in glucostat cultures was taken into account in modeling substrate inhibition kinetics. The inhibition coefficient Ki increased with increasing sugar concentration levels, but it appeared to be unaffected by the type of substrate and almost equal for both substrates at elevated concentration levels. PMID:17211636

  2. Effect of Vanadate on Elevated Blood Glucose and Depressed Cardiac Performance of Diabetic Rats

    NASA Astrophysics Data System (ADS)

    Heyliger, Clayton E.; Tahiliani, Arun G.; McNeill, John H.

    1985-03-01

    The trace element vanadium has an unclear biological function. Vanadate, an oxidized form of vanadium, appears to have an insulin-like action. The effect of vanadate on blood glucose and cardiac performance was assessed in female Wistar rats 6 weeks after they were made diabetic with streptozotocin. When vanadate was administered for a 4-week period to the diabetic rats, their blood glucose was not significantly different from that of nondiabetic controls despite a low serum insulin. In contrast, blood glucose was increased about threefold in the diabetic rats that were not treated with vanadate; these rats also had low insulin levels. Cardiac performance was depressed in the untreated diabetic animals, but the cardiac performance of the vanadate-treated diabetic animals was not significantly different from that of nondiabetic controls. Thus vanadate controlled the high blood glucose and prevented the decline in cardiac performance due to diabetes.

  3. Avian, salamander, and forest floor mercury concentrations increase with elevation in a terrestrial ecosystem.

    PubMed

    Townsend, Jason M; Driscoll, Charles T; Rimmer, Christopher C; McFarland, Kent P

    2014-01-01

    High-elevation ecosystems of the northeastern United States are vulnerable to deposition and environmental accumulation of atmospheric pollutants, yet little work has been done to assess mercury (Hg) concentrations in organisms occupying montane ecosystems. The authors present data on Hg concentrations in ground-foraging insectivorous songbirds, a terrestrial salamander, and forest floor horizons sampled along a forested elevational gradient from 185 m to 1273 m in the Catskill Mountains, New York, USA. Mean Hg concentrations in Catharus thrushes and the salamander Plethodon cinereus increased with elevation, as did Hg concentrations in all forest floor horizons. Mean Hg concentrations in organic soils at approximately 1200 m elevation (503.5 ± 17.7 ng/g, dry wt) were 4.4-fold greater than those at approximately 200 m. Montane ecosystems of the northeastern United States, and probably elsewhere, are exposed to higher levels of atmospheric Hg deposition as reflected in accumulation patterns in the forest floor and associated high-elevation fauna. This information can be used to parameterize and test Hg transport and bioaccumulation models of landscape-specific patterns and may serve as a monitoring tool for decision makers considering future controls on Hg emissions. Further investigation is needed into the potential effects of increased Hg concentrations on high-elevation fauna. PMID:24302165

  4. Effect of Full Correction Versus Partial Correction of Elevated Blood Glucose in the Emergency Department on Hospital Length of Stay.

    PubMed

    Johnson-Clague, Michaela; DiLeo, Jessica; Katz, Michael D; Patanwala, Asad E

    2016-01-01

    There is limited information to guide the extent to which asymptomatic hyperglycemia needs to be corrected in patients presenting to the emergency department (ED) with unrelated complaints. The objective of this study was to compare full correction (FC) versus partial correction (PC) of elevated blood glucose in the ED on hospital length of stay. This was a retrospective cohort study conducted in an academic ED in the United States. Adult diabetic patients with hyperglycemia (blood glucose >200 mg/dL) in the ED who were treated with subcutaneous insulin were included. Patients were categorized based on the level of blood glucose control achieved within the first 24 hours from triage: (1) FC group for whom blood glucose <200 mg/dL was achieved or (2) PC group for whom blood glucose remained ≥200 mg/dL. The primary outcome measure was a comparison of hospital length of stay between groups. A total of 161 patients were included in this study (FC = 81, PC = 80). There was no significant difference between hospital length of stay in the FC [3 days (interquartile range, 1-5 days)] and PC [3 days (interquartile range, 2-6 days)] groups (P = 0.159). In the multivariate analysis, after adjusting for potential confounders, there was no significant association between level of correction and hospital length of stay (log-transformed) (coefficient 0.238; 95% confidence interval, -0.062 to 0.537; P = 0.119; R = 13%). The extent of glucose correction was not associated with a decrease in hospital length of stay in diabetic patients with hyperglycemia in the ED. PMID:25187094

  5. Self-tuning GMV control of glucose concentration in fed-batch baker's yeast production.

    PubMed

    Hitit, Zeynep Yilmazer; Boyacioglu, Havva; Ozyurt, Baran; Ertunc, Suna; Hapoglu, Hale; Akay, Bulent

    2014-04-01

    A detailed system identification procedure and self-tuning generalized minimum variance (STGMV) control of glucose concentration during the aerobic fed-batch yeast growth were realized. In order to determine the best values of the forgetting factor (λ), initial value of the covariance matrix (α), and order of the Auto-Regressive Moving Average with eXogenous (ARMAX) model (n a, n b), transient response data obtained from the real process wereutilized. Glucose flow rate was adjusted according to the STGMV control algorithm coded in Visual Basic in an online computer connected to the system. Conventional PID algorithm was also implemented for the control of the glucose concentration in aerobic fed-batch yeast cultivation. Controller performances were examined by evaluating the integrals of squared errors (ISEs) at constant and random set point profiles. Also, batch cultivation was performed, and microorganism concentration at the end of the batch run was compared with the fed-batch cultivation case. From the system identification step, the best parameter estimation was accomplished with the values λ = 0.9, α = 1,000 and n a = 3, n b = 2. Theoretical control studies show that the STGMV control system was successful at both constant and random glucose concentration set profiles. In addition, random effects given to the set point, STGMV control algorithm were performed successfully in experimental study. PMID:24569909

  6. Muscle Histidine-Containing Dipeptides Are Elevated by Glucose Intolerance in Both Rodents and Men

    PubMed Central

    Stegen, Sanne; Everaert, Inge; Deldicque, Louise; Vallova, Silvia; de Courten, Barbora; Ukropcova, Barbara; Ukropec, Jozef; Derave, Wim

    2015-01-01

    Objective Muscle carnosine and its methylated form anserine are histidine-containing dipeptides. Both dipeptides have the ability to quench reactive carbonyl species and previous studies have shown that endogenous tissue levels are decreased in chronic diseases, such as diabetes. Design and Methods Rodent study: Skeletal muscles of rats and mice were collected from 4 different diet-intervention studies, aiming to induce various degrees of glucose intolerance: 45% high-fat feeding (male rats), 60% high-fat feeding (male rats), cafeteria feeding (male rats), 70% high-fat feeding (female mice). Body weight, glucose-tolerance and muscle histidine-containing dipeptides were assessed. Human study: Muscle biopsies were taken from m. vastus lateralis in 35 males (9 lean, 8 obese, 9 prediabetic and 9 newly diagnosed type 2 diabetic patients) and muscle carnosine and gene expression of muscle fiber type markers were measured. Results Diet interventions in rodents (cafeteria and 70% high-fat feeding) induced increases in body weight, glucose intolerance and levels of histidine-containing dipeptides in muscle. In humans, obese, prediabetic and diabetic men had increased muscle carnosine content compared to the lean (+21% (p>0.1), +30% (p<0.05) and +39% (p<0.05), respectively). The gene expression of fast-oxidative type 2A myosin heavy chain was increased in the prediabetic (1.8-fold, p<0.05) and tended to increase in the diabetic men (1.6-fold, p = 0.07), compared to healthy lean subjects. Conclusion Muscle histidine-containing dipeptides increases with progressive glucose intolerance, in male individuals (cross-sectional). In addition, high-fat diet-induced glucose intolerance was associated with increased muscle histidine-containing dipeptides in female mice (interventional). Increased muscle carnosine content might reflect fiber type composition and/or act as a compensatory mechanism aimed at preventing cell damage in states of impaired glucose tolerance. PMID:25803044

  7. Elevational Variation in Soil Amino Acid and Inorganic Nitrogen Concentrations in Taibai Mountain, China.

    PubMed

    Cao, Xiaochuang; Ma, Qingxu; Zhong, Chu; Yang, Xin; Zhu, Lianfeng; Zhang, Junhua; Jin, Qianyu; Wu, Lianghuan

    2016-01-01

    Amino acids are important sources of soil organic nitrogen (N), which is essential for plant nutrition, but detailed information about which amino acids predominant and whether amino acid composition varies with elevation is lacking. In this study, we hypothesized that the concentrations of amino acids in soil would increase and their composition would vary along the elevational gradient of Taibai Mountain, as plant-derived organic matter accumulated and N mineralization and microbial immobilization of amino acids slowed with reduced soil temperature. Results showed that the concentrations of soil extractable total N, extractable organic N and amino acids significantly increased with elevation due to the accumulation of soil organic matter and the greater N content. Soil extractable organic N concentration was significantly greater than that of the extractable inorganic N (NO3--N + NH4+-N). On average, soil adsorbed amino acid concentration was approximately 5-fold greater than that of the free amino acids, which indicates that adsorbed amino acids extracted with the strong salt solution likely represent a potential source for the replenishment of free amino acids. We found no appreciable evidence to suggest that amino acids with simple molecular structure were dominant at low elevations, whereas amino acids with high molecular weight and complex aromatic structure dominated the high elevations. Across the elevational gradient, the amino acid pool was dominated by alanine, aspartic acid, glycine, glutamic acid, histidine, serine and threonine. These seven amino acids accounted for approximately 68.9% of the total hydrolyzable amino acid pool. The proportions of isoleucine, tyrosine and methionine varied with elevation, while soil major amino acid composition (including alanine, arginine, aspartic acid, glycine, histidine, leucine, phenylalanine, serine, threonine and valine) did not vary appreciably with elevation (p>0.10). The compositional similarity of many

  8. Elevational Variation in Soil Amino Acid and Inorganic Nitrogen Concentrations in Taibai Mountain, China

    PubMed Central

    Yang, Xin; Zhu, Lianfeng; Zhang, Junhua; Jin, Qianyu; Wu, Lianghuan

    2016-01-01

    Amino acids are important sources of soil organic nitrogen (N), which is essential for plant nutrition, but detailed information about which amino acids predominant and whether amino acid composition varies with elevation is lacking. In this study, we hypothesized that the concentrations of amino acids in soil would increase and their composition would vary along the elevational gradient of Taibai Mountain, as plant-derived organic matter accumulated and N mineralization and microbial immobilization of amino acids slowed with reduced soil temperature. Results showed that the concentrations of soil extractable total N, extractable organic N and amino acids significantly increased with elevation due to the accumulation of soil organic matter and the greater N content. Soil extractable organic N concentration was significantly greater than that of the extractable inorganic N (NO3−-N + NH4+-N). On average, soil adsorbed amino acid concentration was approximately 5-fold greater than that of the free amino acids, which indicates that adsorbed amino acids extracted with the strong salt solution likely represent a potential source for the replenishment of free amino acids. We found no appreciable evidence to suggest that amino acids with simple molecular structure were dominant at low elevations, whereas amino acids with high molecular weight and complex aromatic structure dominated the high elevations. Across the elevational gradient, the amino acid pool was dominated by alanine, aspartic acid, glycine, glutamic acid, histidine, serine and threonine. These seven amino acids accounted for approximately 68.9% of the total hydrolyzable amino acid pool. The proportions of isoleucine, tyrosine and methionine varied with elevation, while soil major amino acid composition (including alanine, arginine, aspartic acid, glycine, histidine, leucine, phenylalanine, serine, threonine and valine) did not vary appreciably with elevation (p>0.10). The compositional similarity of many

  9. Classification of diabetes and measurement of blood glucose concentration noninvasively using near infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Li, Zhe; Li, Gang; Yan, Wen-Juan; Lin, Ling

    2014-11-01

    Developing noninvasive blood glucose monitoring method is an to immense need to alleviate the pain and suffering of diabetics associated with the frequent pricking of skin for taking blood sample. A hybrid algorithm for multivariate calibration is proposed to improve the prediction performance of classification of diabetes and measurement of blood glucose concentration by near infrared (NIR) spectroscopy noninvasively. The algorithm is based on wavelet prism modified uninformative variable elimination approach (WP-mUVE) combined with least squares support vector machine (LSSVM), named as WP-mUVE-LSSVM. The method is successfully applied to diabetic classification experiment (in vivo) and blood glucose concentration measurement experiment (in vivo) respectively. Human tongue is selected as the measuring site in this study. To evaluate effectiveness of pretreatment method and quality of calibration models, several usually used pretreatment methods and kernel functions of LSSVM are introduced comparing with our method. Higher quality data is obtained by our pretreatment method owing to the elimination of varying background and noise of spectra data simultaneously. Better prediction accuracy and adaptability are obtained by LSSVM model with radial basis kernel function. The results indicate that WP-mUVE-LSSVM holds promise for the classification of diabetes and measurement of blood glucose concentration noninvasively based on human tongue using NIR spectroscopy.

  10. A Bayesian network for modelling blood glucose concentration and exercise in type 1 diabetes.

    PubMed

    Ewings, Sean M; Sahu, Sujit K; Valletta, John J; Byrne, Christopher D; Chipperfield, Andrew J

    2015-06-01

    This article presents a new statistical approach to analysing the effects of everyday physical activity on blood glucose concentration in people with type 1 diabetes. A physiologically based model of blood glucose dynamics is developed to cope with frequently sampled data on food, insulin and habitual physical activity; the model is then converted to a Bayesian network to account for measurement error and variability in the physiological processes. A simulation study is conducted to determine the feasibility of using Markov chain Monte Carlo methods for simultaneous estimation of all model parameters and prediction of blood glucose concentration. Although there are problems with parameter identification in a minority of cases, most parameters can be estimated without bias. Predictive performance is unaffected by parameter misspecification and is insensitive to misleading prior distributions. This article highlights important practical and theoretical issues not previously addressed in the quest for an artificial pancreas as treatment for type 1 diabetes. The proposed methods represent a new paradigm for analysis of deterministic mathematical models of blood glucose concentration. PMID:24492795

  11. Exploration and Practice in Photoacoustic Measurement for Glucose Concentration Based on Tunable Pulsed Laser Induced Ultrasound

    NASA Astrophysics Data System (ADS)

    Ren, Zhong; Liu, Guodong; Huang, Zhen; Zhao, Dengji; Xiong, Zhihua

    2015-07-01

    In this article, a tunable pulsed laser induced photoacoustic measurement setup of monitoring glucose concentration was established in the forward mode. In experiments, the time-resolved photoacoustic signal of glucose aqueous solution with different concentrations of 0-300 mg/dl were captured and averaged 512 times, and the photoacoustic peak-to-peak values were recorded using the wavelength scan in NIR region of 1300-2300 nm. The optimal characteristic wavelengths of glucose were determined via the difference spectral and the first derivative spectral algorithm, and correction models between peak-to-peak values of optimal wavelengths and concentration gradients were established using multivariate linear regression algorithm. Experimental results demonstrated that the profile and logarithm shape of time-resolved photoacoustic signal for glucose solutions were in good agreement with photoacoustic theories. The prediction effect of optimal wavelength of 1510 nm was best, its root-mean-square errors of correction and prediction were 12.14 and 8.45 mg/dl, respectively, the correlation coefficient reached 0.9856.

  12. The fluctuation of blood glucose, insulin and glucagon concentrations before and after insulin therapy in type 1 diabetes

    NASA Astrophysics Data System (ADS)

    Arif, Idam; Nasir, Zulfa

    2015-09-01

    A dynamical-systems model of plasma glucose, insulin and glucagon concentrations has been developed to investigate the effects of insulin therapy on blood glucose, insulin and glucagon regulations in type 1 diabetic patients. Simulation results show that the normal regulation of blood glucose concentration depends on insulin and glucagon concentrations. On type 1 diabetic case, the role of insulin on regulating blood glucose is not optimal because of the destruction of β cells in pancreas. These β cells destructions cause hyperglycemic episode affecting the whole body metabolism. To get over this, type 1 diabetic patients need insulin therapy to control the blood glucose level. This research has been done by using rapid acting insulin (lispro), long-acting insulin (glargine) and the combination between them to know the effects of insulin therapy on blood glucose, insulin and glucagon concentrations. Simulation results show that these different types of insulin have different effects on blood glucose concentration. Insulin therapy using lispro shows better blood glucose control after consumption of meals. Glargin gives better blood glucose control between meals and during sleep. Combination between lispro and glargine shows better glycemic control for whole day blood glucose level.

  13. Glucose concentration measured by the hybrid coherent anti-Stokes Raman-scattering technique

    NASA Astrophysics Data System (ADS)

    Wang, Xi; Zhang, Aihua; Zhi, Miaochan; Sokolov, Alexei V.; Welch, George R.

    2010-01-01

    We investigate the possibility of using a hybrid coherent anti-Stokes Raman scattering technique for noninvasive monitoring of blood glucose levels. Our technique combines instantaneous coherent excitation of several characteristic molecular vibrations with subsequent probing of these vibrations by an optimally shaped, time-delayed, narrowband laser pulse. This pulse configuration mitigates the nonresonant four-wave mixing background while maximizing the Raman-resonant signal and allows rapid and highly specific detection even in the presence of multiple scattering. Under certain conditions we find that the measured signal is linearly proportional to the glucose concentration due to optical interference with the residual background light, which allows reliable detection of spectral signatures down to medically relevant glucose levels.

  14. Glucose concentration measured by the hybrid coherent anti-Stokes Raman-scattering technique

    SciTech Connect

    Wang Xi; Zhang Aihua; Zhi Miaochan; Sokolov, Alexei V.; Welch, George R.

    2010-01-15

    We investigate the possibility of using a hybrid coherent anti-Stokes Raman scattering technique for noninvasive monitoring of blood glucose levels. Our technique combines instantaneous coherent excitation of several characteristic molecular vibrations with subsequent probing of these vibrations by an optimally shaped, time-delayed, narrowband laser pulse. This pulse configuration mitigates the nonresonant four-wave mixing background while maximizing the Raman-resonant signal and allows rapid and highly specific detection even in the presence of multiple scattering. Under certain conditions we find that the measured signal is linearly proportional to the glucose concentration due to optical interference with the residual background light, which allows reliable detection of spectral signatures down to medically relevant glucose levels.

  15. Influence of various carbohydrate sources on postprandial glucose, insulin and NEFA concentrations in obese cats.

    PubMed

    Mori, A; Ueda, K; Lee, P; Oda, H; Ishioka, K; Sako, T

    2016-01-01

    Carbohydrate is an important source of energy, which can significantly affect postprandial blood glucose and insulin levels in cats. In healthy animals, this is not a big concern; however, in obese and diabetic animals, this is an important detail. In the present study, the impact of four different carbohydrate sources (glucose, maltose, corn starch, and trehalose) on short-term post-prandial serum glucose, insulin, and non-esterified fatty acid (NEFA) concentrations was investigated with four obese cats. Each of the carbohydrate sources was added to a commercial wet food diet for feeding the animals. A significant difference was observed in postprandial glucose, insulin, and NEFA area under the curve (AUC) values between each carbohydrate source in obese cats. Furthermore, glucose and maltose induced the highest postprandial glucose and insulin AUC values, whereas trehalose induced the lowest postprandial glucose and insulin AUC value amongst all carbohydrate sources, respectively, in obese cats. However, trehalose has a higher risk of inducing side effects, such as diarrhea, as compared to other carbohydrate sources. As such, different carbohydrate sources appear to have a very significant impact on post-prandial glycemia and subsequent insulin requirement levels in obese cats. These results might be useful when selecting a prescription diet for obese or diabetic cats. In addition, maltose appears to be capable of inducing experimentally evoked postprandial hyperglycemia in obese cats, which may serve as a good tool for use to check the impact and effectiveness of newly developed oral hypoglycemic drugs or supplements for cats in future experiments. PMID:27487514

  16. Plasma cortisol and glucose concentrations in the striped mullet ( Mugil cephalus L.) subjected to intense handling stress

    NASA Astrophysics Data System (ADS)

    Hong, Wanshu

    1992-03-01

    The plasma cortisol and glucose concentrations were determined in mature female striped mullet ( Mugil cephalus L.) subjected to short term intense handling stress. The results indicated that plasma cortisol levels reached a peak 20 min after stress and declined gradually afterwards. The highest concentration of plasma glucose was observed 30 min after stress. The present study showed that the rise of plasma glucose was associated with the plasma cortisol levels.

  17. Growth, biofilm formation, antifungal susceptibility and oxidative stress resistance of Candida glabrata are affected by different glucose concentrations.

    PubMed

    Ng, Tzu Shan; Desa, Mohd Nasir Mohd; Sandai, Doblin; Chong, Pei Pei; Than, Leslie Thian Lung

    2016-06-01

    Glucose is an important fuel source to support many living organisms. Its importance in the physiological fitness and pathogenicity of Candida glabrata, an emerging human fungal pathogen has not been extensively studied. The present study aimed to investigate the effects of glucose on the growth, biofilm formation, antifungal susceptibility and oxidative stress resistance of C. glabrata. In addition, its effect on the expression of a putative high affinity glucose sensor gene, SNF3 was also investigated. Glucose concentrations were found to exert effects on the physiological responses of C. glabrata. The growth rate of the species correlated positively to the amount of glucose. In addition, low glucose environments were found to induce C. glabrata to form biofilm and resist amphotericin B. Conversely, high glucose environments promoted oxidative stress resistance of C. glabrata. The expression of CgSNF3 was found to be significantly up-regulated in low glucose environments. The expression of SNF3 gene in clinical isolates was found to be higher compared to ATCC laboratory strains in low glucose concentrations, which may explain the better survivability of clinical isolates in the low glucose environment. These observations demonstrated the impact of glucose in directing the physiology and virulence fitness of C. glabrata through the possible modulation by SNF3 as a glucose sensor, which in turn aids the species to adapt, survive and thrive in hostile host environment. PMID:26358577

  18. Placental adiponectin gene DNA methylation levels are associated with mothers' blood glucose concentration.

    PubMed

    Bouchard, Luigi; Hivert, Marie-France; Guay, Simon-Pierre; St-Pierre, Julie; Perron, Patrice; Brisson, Diane

    2012-05-01

    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. PMID:22396200

  19. Prevalence of Elevated Glycated Hemoglobin Concentrations in the Polycystic Ovary Syndrome: Anthropometrical and Metabolic Relationship in Amazonian Women

    PubMed Central

    de Medeiros, Sebastiao Freitas; Yamamoto, Marcia Marly Winck; Bueno, Herica Bernardes; Belizario, Danilla; Barbosa, Jacklyne Silva

    2014-01-01

    Background To determine the prevalence of elevated glycated hemoglobin (HbA1c) and to examine its relationship with other carbohydrate metabolic parameter among Brazilian women with polycystic ovary syndrome (PCOS). Methods A cross-sectional study including 288 PCOS patients was conducted. Anthropometrical, clinical, biochemical and endocrine parameters were evaluated. Results The mean age was 26.92 ± 5.51 years. HbA1c mean concentration was 5.83±1.34%. In 38.54% of patients, HbA1c was ≥ 5.7%. HbA1c was positively correlated with body weight (r = 0.142, P = 0.017), body mass index (P = 0.000), waist:hip ratio (P = 0.000), fat mass (P = 0.000), conicity index (P = 0.000), triglyceride (P = 0.001), C-peptide (P = 0.000), total testosterone (P = 0.003), free testosterone (P = 0.000), free androgen index (P = 0.006) and fasting insulin (P = 0.025). Using the oral glucose tolerance test, HbA1c showed positive correlation with glucose concentrations at any point in time (P < 0.05). Conclusions HbA1c was elevated in nearly 40% of PCOS patients and it showed positive correlation with several anthropometric and metabolic factors and androgen levels. The current study provides further evidence that HbA1C is higher in PCOS patients and may have a potential role in the prediction of dysglycemic disease in these women. PMID:24883154

  20. Differential Responses of Plasma Adropin Concentrations To Dietary Glucose or Fructose Consumption In Humans

    PubMed Central

    Butler, Andrew A.; St-Onge, Marie-Pierre; Siebert, Emily A.; Medici, Valentina; Stanhope, Kimber L.; Havel, Peter J.

    2015-01-01

    Adropin is a peptide hormone encoded by the Energy Homeostasis Associated (ENHO) gene whose physiological role in humans remains incompletely defined. Here we investigated the impact of dietary interventions that affect systemic glucose and lipid metabolism on plasma adropin concentrations in humans. Consumption of glucose or fructose as 25% of daily energy requirements (E) differentially affected plasma adropin concentrations (P < 0.005) irrespective of duration, sex or age. Glucose consumption reduced plasma adropin from 3.55 ± 0.26 to 3.28 ± 0.23 ng/ml (N = 42). Fructose consumption increased plasma adropin from 3.63 ± 0.29 to 3.93 ± 0.34 ng/ml (N = 45). Consumption of high fructose corn syrup (HFCS) as 25% E had no effect (3.43 ± 0.32 versus 3.39 ± 0.24 ng/ml, N = 26). Overall, the effect of glucose, HFCS and fructose on circulating adropin concentrations were similar to those observed on postprandial plasma triglyceride concentrations. Furthermore, increases in plasma adropin levels with fructose intake were most robust in individuals exhibiting hypertriglyceridemia. Individuals with low plasma adropin concentrations also exhibited rapid increases in plasma levels following consumption of breakfasts supplemented with lipids. These are the first results linking plasma adropin levels with dietary sugar intake in humans, with the impact of fructose consumption linked to systemic triglyceride metabolism. In addition, dietary fat intake may also increase circulating adropin concentrations. PMID:26435060

  1. Effect of enoxacin, felbinac, and sparfloxacin on fatty acid metabolism and glucose concentrations in rat tissues.

    PubMed

    Kasuya, Fumiyo; Miwa, Yasushi; Kazumi, Maya; Inoue, Hiroyuki; Ohta, Hiroyuki

    2011-05-01

    Multiple changes in metabolic levels could be useful for understanding physiological toxicity. To explore further risk factors for the convulsions induced by the interaction of nonsteroidal anti-inflammatory and new quinolone antimicrobial drugs, the effect of sparfloxacin, enoxacin, and felbinac on fatty acid metabolism and glucose concentrations in the liver, brain, and blood of rats was investigated. The levels of long-chain acyl-CoAs (C(18:1) and C(20:4)) in the liver and brain were decreased at the onset of convulsions induced by the coadministration of enoxacin with felbinac. Then, glucose concentrations in the liver and blood were decreased, whereas they were increased in a dose-dependant manner in the brain. However, the formation of acyl-CoAs and glucose levels in the liver, brain, and blood was not significantly influenced by enoxacin, felbinac, and sparfloxacin alone, respectively. The disturbance of both fatty acid metabolism and glucose levels might be associated with the increased susceptibility to convulsions, which may contribute to further understanding of the toxic effects associated with these drugs. PMID:21633127

  2. The Influence of Variation in Time and HCl Concentration to the Glucose Produced from Kepok Banana

    NASA Astrophysics Data System (ADS)

    Widodo M, Rohman; Noviyanto, Denny; RM, Faisal

    2016-01-01

    Kepok banana (Musa paradisiaca) is a plant that has many advantagesfrom its fruit, stems, leaves, flowers and cob. However, we just tend to take benefit from the fruit. We grow and harvest the fruit without taking advantages from other parts. So they would be a waste or detrimental to animal nest if not used. The idea to take the benefit from the banana crop yields, especially cob is rarely explored. This study is an introduction to the use of banana weevil especially from the glucose it contains. This study uses current methods of hydrolysis using HCl as a catalyst with the concentration variation of 0.4 N, 0.6 N and 0.8 N and hydrolysis times variation of 20 minutes, 25 minutes and 30 minutes. The stages in the hydrolysis include preparation of materials, the process of hydrolysis and analysis of test results using Fehling and titrate with standard glucose solution. HCl is used as a catalyst because it is cheaper than the enzyme that has the same function. NaOH 60% is used for neutralizing the pH of the filtrate result of hydrolysis. From the results of analysis, known thatthe biggest yield of glucose is at concentration 0.8 N and at 30 minutes reaction, it contains 6.25 gram glucose / 20 gram dry sampel, and the convertion is 27.22% at 20 gram dry sampel.

  3. Increased C availability at elevated carbon dioxide concentration improves N assimilation in a legume.

    PubMed

    Rogers, Alistair; Gibon, Yves; Stitt, Mark; Morgan, Patrick B; Bernacchi, Carl J; Ort, Donald R; Long, Stephen P

    2006-08-01

    Plant growth is typically stimulated at elevated carbon dioxide concentration ([CO2]), but a sustained and maximal stimulation of growth requires acquisition of additional N in proportion to the additional C fixed at elevated [CO2]. We hypothesized that legumes would be able to avoid N limitation at elevated [CO2]. Soybean was grown without N fertilizer from germination to final senescence at elevated [CO2] over two growing seasons under fully open-air conditions, providing a model legume system. Measurements of photosynthesis and foliar carbohydrate content showed that plants growing at elevated [CO2] had a c. 25% increase in the daily integral of photosynthesis and c. 58% increase in foliar carbohydrate content, suggesting that plants at elevated [CO2] had a surplus of photosynthate. Soybeans had a low leaf N content at the beginning of the season, which was a further c. 17% lower at elevated [CO2]. In the middle of the season, ureide, total amino acid and N content increased markedly, and the effect of elevated [CO2] on leaf N content disappeared. Analysis of individual amino acid levels supported the conclusion that plants at elevated [CO2] overcame an early-season N limitation. These soybean plants showed a c. 16% increase in dry mass at final harvest and showed no significant effect of elevated [CO2] on leaf N, protein or total amino acid content in the latter part of the season. One possible explanation for these findings is that N fixation had increased, and that these plants had acclimated to the increased N demand at elevated [CO2]. PMID:16898025

  4. Effects of glucose concentrations on cadmium, copper, mercury, and zinc toxicity to a Klebsiella sp

    SciTech Connect

    Brynhildsen, L.; Lundgren, B.V.; Allard, B.; Rosswall, T.

    1988-07-01

    The influence of glucose concentration on Cd, CU, Hg, and Zn toxicity to a Klebsiella sp. was studied by following the degradation of /sup 14/C-labeled glucose at pH 6.0. Uptake of /sup 14/C into the cells was also determined. The carbon concentrations ranged from 0.01 to 40 mg liter/sup -1/, which are equivalent to soluble C concentrations in natural environments. The toxicity of Cu, Cd, and Zn to a Klebsiella sp. was affected considerably by the C concentration. Copper at 10/sup -5/ M was toxic when the carbon concentration was 10 or 40 mg liter/sup -1/, while at 0.01 to 1.0 mg liter/sup -1/ no toxicity was observed. Cadmium and zinc were toxic at 10/sup -2/ M in media containing 0.01 to 1.0 mg of C liter/sup -1/. At C concentrations greater than 1.0 mg liter/sup -1/, the inhibition of glucose degradation and carbon assimilation was observed at 10/sup -3/ M Cd and Zn. The toxicity of mercury seemed to be independent of the C concentration. Results of this study showed that the nutritional state of an organism may have a profound effect on its sensitivity to metals. Metals taken up by energy-driven transport system may be less toxic under conditions of C starvation. The C concentration should be taken into account when evaluating results from toxicity studies, especially as most microorganisms in nature live under energy-limited conditions.

  5. Growth at Elevated Ozone or Elevated Carbon Dioxide Concentration Alters Antioxidant Capacity and Response to Acute Oxidative Stress in Soybean (Glycine max)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In order to test the hypothesis that atmospheric environment alters total antioxidant capacity of plants and their capacity to respond to acute oxidative stress, soybeans were grown under at elevated carbon dioxide concentration ([CO2]) or elevated ozone concentration ([O3]), and then exposed to an ...

  6. Improved noncontact optical sensor for detection of glucose concentration and indication of dehydration level

    PubMed Central

    Ozana, Nisan; Arbel, Nadav; Beiderman, Yevgeny; Mico, Vicente; Sanz, Martin; Garcia, Javier; Anand, Arun; Javidi, Baharam; Epstein, Yoram; Zalevsky, Zeev

    2014-01-01

    The ability to extract different bio-medical parameters from one single wristwatch device can be very applicable. The wearable device that is presented in this paper is based on two optical approaches. The first is the extraction and separation of remote vibration sources and the second is the rotation of linearly polarized light by certain materials exposed to magnetic fields. The technique is based on tracking of temporal changes of reflected secondary speckles produced in the wrist when being illuminated by a laser beam. Change in skin’s temporal vibration profile together with change in the magnetic medium that is generated by time varied glucose concentration caused these temporal changes. In this paper we present experimental tests which are the first step towards an in vivo noncontact device for detection of glucose concentration in blood. The paper also shows very preliminary results for qualitative capability for indication of dehydration. PMID:24940550

  7. Prochlorococcus can use the Pro1404 transporter to take up glucose at nanomolar concentrations in the Atlantic Ocean

    PubMed Central

    Muñoz-Marín, María del Carmen; Luque, Ignacio; Zubkov, Mikhail V.; Hill, Polly G.; Diez, Jesús; García-Fernández, José Manuel

    2013-01-01

    Prochlorococcus is responsible for a significant part of CO2 fixation in the ocean. Although it was long considered an autotrophic cyanobacterium, the uptake of organic compounds has been reported, assuming they were sources of limited biogenic elements. We have shown in laboratory experiments that Prochlorococcus can take up glucose. However, the mechanisms of glucose uptake and its occurrence in the ocean have not been shown. Here, we report that the gene Pro1404 confers capability for glucose uptake in Prochlorococcus marinus SS120. We used a cyanobacterium unable to take up glucose to engineer strains that express the Pro1404 gene. These recombinant strains were capable of specific glucose uptake over a wide range of glucose concentrations, showing multiphasic transport kinetics. The Ks constant of the high affinity phase was in the nanomolar range, consistent with the average concentration of glucose in the ocean. Furthermore, we were able to observe glucose uptake by Prochlorococcus in the central Atlantic Ocean, where glucose concentrations were 0.5–2.7 nM. Our results suggest that Prochlorococcus are primary producers capable of tuning their metabolism to energetically benefit from environmental conditions, taking up not only organic compounds with key limiting elements in the ocean, but also molecules devoid of such elements, like glucose. PMID:23569224

  8. Prochlorococcus can use the Pro1404 transporter to take up glucose at nanomolar concentrations in the Atlantic Ocean.

    PubMed

    Muñoz-Marín, María del Carmen; Luque, Ignacio; Zubkov, Mikhail V; Hill, Polly G; Diez, Jesús; García-Fernández, José Manuel

    2013-05-21

    Prochlorococcus is responsible for a significant part of CO2 fixation in the ocean. Although it was long considered an autotrophic cyanobacterium, the uptake of organic compounds has been reported, assuming they were sources of limited biogenic elements. We have shown in laboratory experiments that Prochlorococcus can take up glucose. However, the mechanisms of glucose uptake and its occurrence in the ocean have not been shown. Here, we report that the gene Pro1404 confers capability for glucose uptake in Prochlorococcus marinus SS120. We used a cyanobacterium unable to take up glucose to engineer strains that express the Pro1404 gene. These recombinant strains were capable of specific glucose uptake over a wide range of glucose concentrations, showing multiphasic transport kinetics. The Ks constant of the high affinity phase was in the nanomolar range, consistent with the average concentration of glucose in the ocean. Furthermore, we were able to observe glucose uptake by Prochlorococcus in the central Atlantic Ocean, where glucose concentrations were 0.5-2.7 nM. Our results suggest that Prochlorococcus are primary producers capable of tuning their metabolism to energetically benefit from environmental conditions, taking up not only organic compounds with key limiting elements in the ocean, but also molecules devoid of such elements, like glucose. PMID:23569224

  9. The effect of extremely high glucose concentrations on 21 routine chemistry and thyroid Abbott assays: interference study

    PubMed Central

    Çuhadar, Serap; Köseoğlu, Mehmet; Çinpolat, Yasemin; Buğdaycı, Güler; Usta, Murat; Semerci, Tuna

    2016-01-01

    Introduction Extremely high glucose concentrations have been shown to interfere with creatinine assays especially with Jaffe method in peritoneal dialysate. Because diabetes is the fastest growing chronic disease in the world, laboratories study with varying glucose concentrations. We investigated whether different levels of glucose spiked in serum interfere with 21 routine chemistry and thyroid assays at glucose concentrations between 17-51 mmol/L. Materials and methods Baseline (group I) serum pool with glucose concentration of 5.55 (5.44-5.61) mmol/L was prepared from patient sera. Spiking with 20% dextrose solution, sample groups were obtained with glucose concentrations: 17.09, 34.52, and 50.95 mmol/L (group II, III, IV, respectively). Total of 21 biochemistry analytes and thyroid tests were studied on Abbott c8000 and i2000sr with commercial reagents. Bias from baseline value was checked statistically and clinically. Results Creatinine increased significantly by 8.74%, 31.66%, 55.31% at groups II, III, IV, respectively with P values of < 0.001. At the median glucose concentration of 50.95 mmol/L, calcium, albumin, chloride and FT4 biased significantly clinically (-0.85%, 1.63%, 0.65%, 7.4% with P values 0.138, 0.214, 0.004, < 0.001, respectively). Remaining assays were free of interference. Conclusion Among the numerous biochemical parameters studied, only a few parameters are affected by dramatically increased glucose concentration. The creatinine measurements obtained in human sera with the Jaffe alkaline method at high glucose concentrations should be interpreted with caution. Other tests that were affected with extremely high glucose concentrations were calcium, albumin, chloride and FT4, hence results should be taken into consideration in patients with poor diabetic control. PMID:26981018

  10. Effect of elevated CO2 concentration on photosynthetic characteristics of hyperaccumulator Sedum alfredii under cadmium stress.

    PubMed

    Li, Tingqiang; Tao, Qi; Di, Zhenzhen; Lu, Fan; Yang, Xiaoe

    2015-07-01

    The combined effects of elevated CO2 and cadmium (Cd) on photosynthetic rate, chlorophyll fluorescence and Cd accumulation in hyperaccumulator Sedum alfredii Hance were investigated to predict plant growth under Cd stress with rising atmospheric CO2 concentration. Both pot and hydroponic experiments were conducted and the plants were grown under ambient (350 µL L(-1)) or elevated (800 µL L(-1)) CO2 . Elevated CO2 significantly (P < 0.05) increased Pn (105%-149%), Pnmax (38.8%-63.0%) and AQY (20.0%-34.8%) of S. alfredii in all the Cd treatments, but reduced chlorophyll concentration, dark respiration and photorespiration. After 10 days growth in medium with 50 µM Cd under elevated CO2 , PSII activities were significantly enhanced (P < 0.05) with Pm, Fv/Fm, Φ(II) and qP increased by 66.1%, 7.5%, 19.5% and 16.4%, respectively, as compared with ambient-grown plants. Total Cd uptake in shoot of S. alfredii grown under elevated CO2 was increased by 44.1%-48.5%, which was positively correlated with the increase in Pn. These results indicate that elevated CO2 promoted the growth of S. alfredii due to increased photosynthetic carbon uptake rate and photosynthetic light-use efficiency, and showed great potential to improve the phytoextraction of Cd by S. alfredii. PMID:25370532

  11. Kinetics of Bacillus thuringiensis var. israelensis growth on high glucose concentrations.

    PubMed

    Berbert-Molina, M A; Prata, A M R; Pessanha, L G; Silveira, M M

    2008-11-01

    The kinetic and general growth features of Bacillus thuringiensis var. israelensis were evaluated. Initial glucose concentration (S0) in fermentation media varied from 10 to 152 g/l. The results afforded to characterize four morphologically and physiologically well-defined culture phases, independent of S0 values: Phase I, vegetative growth; Phase II, transition to sporulation; Phase III, sporulation; and Phase IV, spores maturation and cell lysis. Important process parameters were also determined. The maximum specific growth rates (microX,m) were not affected with S0 up to 75 g/l (1.0-1.1 per hour), but higher glucose concentrations resulted in growth inhibition by substrate, revealed by a reduction in microX,m values. These higher S0 values led to longer Phases III and IV and delayed sporulation. Similar biomass concentrations (Xm=15.2-15.9 g/l) were achieved with S0 over 30.8 g/l, with increasing residual substrate, suggesting a limitation in some other nutrients and the use of glucose to form other metabolites. In this case, with S0 from 30.8 to 152 g/l, cell yield (YX/S) decreased from 0.58 to 0.41 g/g. On the other hand, with S0=10 g/l growth was limited by substrate, and YX/S has shown its maximum value (0.83 g/g). PMID:18712542

  12. Carbohydrate concentrations and freezing stress resistance of silver birch buds grown under elevated temperature and ozone.

    PubMed

    Riikonen, Johanna; Kontunen-Soppela, Sari; Vapaavuori, Elina; Tervahauta, Arja; Tuomainen, Marjo; Oksanen, Elina

    2013-03-01

    The effects of slightly elevated temperature (+0.8 °C), ozone (O3) concentration (1.3 × ambient O3 concentration) and their combination on over-wintering buds of Betula pendula Roth were studied after two growing seasons of exposure in the field. Carbohydrate concentrations, freezing stress resistance (FSR), bud dry weight to fresh weight ratio, and transcript levels of cytochrome oxidase (COX), alternative oxidase (AOX) and dehydrin (LTI36) genes were studied in two clones (clones 12 and 25) in December. Elevated temperature increased the bud dry weight to fresh weight ratio and the ratio of raffinose family oligosaccharides to sucrose and the transcript levels of the dehydrin (LTI36) gene (in clone 12 only), but did not alter the FSR of the buds. Genotype-specific alterations in carbohydrate metabolism were found in the buds grown under elevated O3. The treatments did not significantly affect the transcript level of the COX or AOX genes. No clear pattern of an interactive effect between elevated temperature and O3 concentration was found. According to these data, the increase in autumnal temperatures and slightly increasing O3 concentrations do not increase the risk for freeze-induced damage in winter in silver birch buds, although some alterations in bud physiology occur. PMID:23425688

  13. Quantifying the effect of milli-molar glucose concentration on thickness of rabbit cornea with optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Ghosn, Mohamad G.; Leba, Michael; Vijayananda, Astha; Ansari, Rafat R.; Larin, Kirill V.

    2009-02-01

    The cornea contributes about 65% of the eye's ability to refract light. Thus, any fluctuation in corneal thickness can cause noticeable changes in vision. The presence of glucose molecules induces a driving force for water to leave the collagen fibrils in the cornea due to the concentration gradient created, thus changing its thickness. In this study, the effect of various milli-molar glucose concentrations on corneal thickness was explored using Optical Coherence Tomography. Whole rabbit eyes were placed in a specially designed dish while immersed in saline to ensure proper hydration of the eye. The cornea was imaged for 10 minutes. In 30 minute increments, a higher concentration of glucose was added, bringing the overall glucose concentration to 10, 15, 20, 25, and 30 mM. The thickness of the cornea was measured every 2 minutes. Ultimately, an inverse relationship was observed, indicating that the increase in glucose concentration yielded a decrease in the corneal thickness. From three separate experiments, the cornea experienced 8 +/- 1, 27 +/- 1, 44 +/- 3, 58 +/- 3, and 64 +/- 3 μm decrease in thickness from its starting value while exposed to 10, 15, 20, 25, and 30 mM solutions of glucose, respectively. This relationship provides insight on the physiological changes of the cornea as a result of different glucose concentrations. This could potentially be useful in monitoring blood-glucose levels through the eye.

  14. Glucose concentration alters dissolved oxygen levels in liquid cultures of Beauveria bassiana and affects formation and bioefficacy of blastospores.

    PubMed

    Mascarin, Gabriel Moura; Jackson, Mark A; Kobori, Nilce Naomi; Behle, Robert W; Dunlap, Christopher A; Delalibera Júnior, Ítalo

    2015-08-01

    The filamentous fungus Beauveria bassiana is an economically important pathogen of numerous arthropod pests and is able to grow in submerged culture as filaments (mycelia) or as budding yeast-like blastospores. In this study, we evaluated the effect of dissolved oxygen and high glucose concentrations on blastospore production by submerged cultures of two isolates of B. bassiana, ESALQ1432 and GHA. Results showed that maintaining adequate dissolved oxygen levels coupled with high glucose concentrations enhanced blastospore yields by both isolates. High glucose concentrations increased the osmotic pressure of the media and coincided with higher dissolved oxygen levels and increased production of significantly smaller blastospores compared with blastospores produced in media with lower concentrations of glucose. The desiccation tolerance of blastospores dried to less than 2.6 % moisture was not affected by the glucose concentration of the medium but was isolate dependent. Blastospores of isolate ESALQ1432 produced in media containing 140 g glucose L(-1) showed greater virulence toward whitefly nymphs (Bemisia tabaci) as compared with blastospores produced in media containing 40 g glucose L(-1). These results suggest a synergistic effect between glucose concentration and oxygen availability on changing morphology and enhancing the yield and efficacy of blastospores of B. bassiana, thereby facilitating the development of a cost-effective production method for this blastospore-based bioinsecticide. PMID:25947245

  15. Naturally Elevated Monomethylmercury and Mercury Concentrations of Redwood Trees of Coastal California

    NASA Astrophysics Data System (ADS)

    Rytuba, J. J.

    2014-12-01

    Redwood trees (Sequoia sempervirens) of coastal California acquire up to a third of their annual water through direct foliar uptake from summer coastal fog. Coastal fog contains elevated concentrations of monomethylmercury (MMeHg) up to 9.8 ng/L (Weiss-Penzias et al., Geophys Res Letters, 39). MMeHg introduced by fog is concentrated in old growth redwood trees throughout their distribution along the California coast. High concentrations of MMeHg occur in living redwood needles (0.20 to 3.76 ng/g dry weight basis, dwb) and are about 2 orders of magnitude greater than typical in evergreen needles that do not receive coastal fog water. MMeHg concentration in living redwood needles changes seasonally reaching a maximum at the end of the fog season (October) and a minimum at the beginning of the fog season (March). Hg concentrations in living redwood needles range from 21.7 to 80.5 ng/g (dwb), comparable to reported values for evergreen needles from non-coastal trees. Redwoods planted in the suburban landscape inland from the coastal fog belt have considerably lower MMeHg concentrations (<0.20 ng/g) but similar Hg concentrations to redwoods in their natural coastal environment. Redwood needles die after 3 years and contain comparable concentrations of MMeHg to those in living needles from the same old growth redwoods but Hg concentrations are much higher (up to 142 ng/g) since Hg accumulates throughout the life of the needle. Stream waters in old growth redwood forests under low and high flow conditions have very low concentrations of MMeHg (<.02 ng/L). However, under high flow conditions Hg concentrations are elevated, up to 22 ng/L, compared to low flow conditions (1.3-3.15 ng/L) and in rainwater (5.4 ng/L). MMeHg concentrations in stream waters are not elevated because MMeHg is retained in redwood needles. Hg concentrations in high flow stream waters are elevated because soils developed under old growth redwoods have elevated concentrations of Hg, up to 280 ng/g (3

  16. Acute ingestion of catechin-rich green tea improves postprandial glucose status and increases serum thioredoxin concentrations in postmenopausal women.

    PubMed

    Takahashi, Masaki; Miyashita, Masashi; Suzuki, Katsuhiko; Bae, Seong-Ryu; Kim, Hyeon-Ki; Wakisaka, Takuya; Matsui, Yuji; Takeshita, Masao; Yasunaga, Koichi

    2014-11-14

    Elevated postprandial hyperglycaemia and oxidative stress increase the risks of type 2 diabetes and CVD. Green tea catechin possesses antidiabetic properties and antioxidant capacity. In the present study, we examined the acute and continuous effects of ingestion of catechin-rich green tea on postprandial hyperglycaemia and oxidative stress in healthy postmenopausal women. Participants were randomly assigned into the placebo (P, n 11) or green tea (GT, n 11) group. The GT group consumed a catechin-rich green tea (catechins 615 mg/350 ml) beverage per d for 4 weeks. The P group consumed a placebo (catechins 92 mg/350 ml) beverage per d for 4 weeks. At baseline and after 4 weeks, participants of each group consumed their designated beverages with breakfast and consumed lunch 3 h after breakfast. Venous blood samples were collected in the fasted state (0 h) and at 2, 4 and 6 h after breakfast. Postprandial glucose concentrations were 3 % lower in the GT group than in the P group (three-factor ANOVA, group × time interaction, P< 0·05). Serum concentrations of the derivatives of reactive oxygen metabolites increased after meals (P< 0·05), but no effect of catechin-rich green tea intake was observed. Conversely, serum postprandial thioredoxin concentrations were 5 % higher in the GT group than in the P group (three-factor ANOVA, group × time interaction, P< 0·05). These findings indicate that an acute ingestion of catechin-rich green tea has beneficial effects on postprandial glucose and redox homeostasis in postmenopausal women. PMID:25230741

  17. Serum Vitamin D Concentrations and Unexplained Elevation in ALT Among US Adults

    PubMed Central

    Chalasani, Naga

    2013-01-01

    Background Low serum levels of vitamin D are associated with metabolic syndrome. Participants in NHANES III with unexplained elevation in ALT levels have high prevalence of metabolic syndrome. We hypothesized that the serum concentrations of vitamin D were inversely associated with unexplained elevation in ALT. Methods A total of 6,826 fasting subjects underwent morning physical examination and met the inclusion and exclusion criteria. From these participants, we have constructed cases with unexplained elevation in ALT (n = 308) and compared their serum vitamin D concentrations to matched controls with normal ALT (N = 979). We examined the prevalence of unexplained elevation in ALT level across different quartiles of vitamin D levels. Results Participants with unexplained elevation in ALT had significantly lower serum vitamin D levels compared to controls (61.8 ± 26.0 nmol/l vs. 66.8 ± 27.1 nmol/l, P < 0.01). The unadjusted prevalence of unexplained elevation in ALT in patients with highest to lowest quartiles of serum vitamin D levels were 21.4, 21.4, 25.6, and 31.5%, respectively. Compared to lowest quartile, patients with top two quartiles of serum vitamin D levels had significantly lower prevalence of unexplained elevation in ALT (OR, 95% CI for highest quartile 0.62 [0.43–0.89] and for third quartile 0.61 [0.42–0.86]). This relationship persisted even after controlling for metabolic syndrome, insulin resistance, and serum triglycerides. Conclusions This study suggests a significant inverse relationship between serum vitamin D levels and unexplained elevation in ALT. Further studies are needed to confirm this observation and to understand the basis for and implications of this observation. PMID:21503677

  18. Carbon fluxes acclimate more strongly to elevated growth temperatures than to elevated CO2 concentrations in a northern conifer.

    PubMed

    Kroner, Yulia; Way, Danielle A

    2016-08-01

    Increasing temperatures and atmospheric CO2 concentrations will affect tree carbon fluxes, generating potential feedbacks between forests and the global climate system. We studied how elevated temperatures and CO2 impacted leaf carbon dynamics in Norway spruce (Picea abies), a dominant northern forest species, to improve predictions of future photosynthetic and respiratory fluxes from high-latitude conifers. Seedlings were grown under ambient (AC, c. 435 μmol mol(-1) ) or elevated (EC, 750 μmol mol(-1) ) CO2 concentrations at ambient, +4 °C, or +8 °C growing temperatures. Photosynthetic rates (Asat ) were high in +4 °C/EC seedlings and lowest in +8 °C spruce, implying that moderate, but not extreme, climate change may stimulate carbon uptake. Asat , dark respiration (Rdark ), and light respiration (Rlight ) rates acclimated to temperature, but not CO2 : the thermal optimum of Asat increased, and Rdark and Rlight were suppressed under warming. In all treatments, the Q10 of Rlight (the relative increase in respiration for a 10 °C increase in leaf temperature) was 35% higher than the Q10 of Rdark , so the ratio of Rlight to Rdark increased with rising leaf temperature. However, across all treatments and a range of 10-40 °C leaf temperatures, a consistent relationship between Rlight and Rdark was found, which could be used to model Rlight in future climates. Acclimation reduced daily modeled respiratory losses from warm-grown seedlings by 22-56%. When Rlight was modeled as a constant fraction of Rdark , modeled daily respiratory losses were 11-65% greater than when using measured values of Rlight . Our findings highlight the impact of acclimation to future climates on predictions of carbon uptake and losses in northern trees, in particular the need to model daytime respiratory losses from direct measurements of Rlight or appropriate relationships with Rdark . PMID:26728638

  19. Intermittent Elevated Radium Concentrations in Coastal Plain Groundwater of South Carolina, U.S.A.

    SciTech Connect

    Denham, Miles; Millings, Margaret; Noonkester, Jay

    2005-09-22

    To learn the cause of intermittent radium concentrations in groundwater of Coastal Plain aquifers, 31 groundwater wells in South Carolina, U.S.A. were sampled for radium and other geochemical parameters. Sediments cored from near the well screens were also sampled to examine any relationship between sediment properties and radium concentration in the groundwater. Elevated radium concentrations only occurred in groundwater with low electrical conductivity and pH values below 6.3. The adsorption edge for radium on hematite--a major surface active mineral in these aquifers--is at a pH value of about 6. Near this value, small changes in pH can result in significant adsorption or desorption of radium. In groundwater with initially low alkalinity, small intermittent decreases in partial pressure of carbon dioxide in groundwater cause decreases in pH and desorption of radium. The result is intermittent elevated radium concentrations.

  20. Impact of elevated CO2 concentration under three soil water levels on growth of Cinnamomum camphora *

    PubMed Central

    Zhao, Xing-Zheng; Wang, Gen-Xuan; Shen, Zhu-Xia; Zhang, Hao; Qiu, Mu-Qing

    2006-01-01

    Forest plays very important roles in global system with about 35% land area producing about 70% of total land net production. It is important to consider both elevated CO2 concentrations and different soil moisture when the possible effects of elevated CO2 concentration on trees are assessed. In this study, we grew Cinnamomum camphora seedlings under two CO2 concentrations (350 μmol/mol and 500 μmol/mol) and three soil moisture levels [80%, 60% and 40% FWC (field water capacity)] to focus on the effects of exposure of trees to elevated CO2 on underground and aboveground plant growth, and its dependence on soil moisture. The results indicated that high CO2 concentration has no significant effects on shoot height but significantly impacts shoot weight and ratio of shoot weight to height under three soil moisture levels. The response of root growth to CO2 enrichment is just reversed, there are obvious effects on root length growth, but no effects on root weight growth and ratio of root weight to length. The CO2 enrichment decreased 20.42%, 32.78%, 20.59% of weight ratio of root to shoot under 40%, 60% and 80% FWC soil water conditions, respectively. And elevated CO2 concentration significantly increased the water content in aboveground and underground parts. Then we concluded that high CO2 concentration favours more tree aboveground biomass growth than underground biomass growth under favorable soil water conditions. And CO2 enrichment enhanced lateral growth of shoot and vertical growth of root. The responses of plants to elevated CO2 depend on soil water availability, and plants may benefit more from CO2 enrichment with sufficient water supply. PMID:16532530

  1. Impact of elevated CO2 concentration under three soil water levels on growth of Cinnamomum camphora.

    PubMed

    Zhao, Xing-zheng; Wang, Gen-xuan; Shen, Zhu-xia; Zhang, Hao; Qiu, Mu-qing

    2006-04-01

    Forest plays very important roles in global system with about 35% land area producing about 70% of total land net production. It is important to consider both elevated CO(2) concentrations and different soil moisture when the possible effects of elevated CO(2) concentration on trees are assessed. In this study, we grew Cinnamomum camphora seedlings under two CO(2) concentrations (350 micromol/mol and 500 micromol/mol) and three soil moisture levels [80%, 60% and 40% FWC (field water capacity)] to focus on the effects of exposure of trees to elevated CO(2) on underground and aboveground plant growth, and its dependence on soil moisture. The results indicated that high CO(2) concentration has no significant effects on shoot height but significantly impacts shoot weight and ratio of shoot weight to height under three soil moisture levels. The response of root growth to CO(2) enrichment is just reversed, there are obvious effects on root length growth, but no effects on root weight growth and ratio of root weight to length. The CO(2) enrichment decreased 20.42%, 32.78%, 20.59% of weight ratio of root to shoot under 40%, 60% and 80% FWC soil water conditions, respectively. And elevated CO(2) concentration significantly increased the water content in aboveground and underground parts. Then we concluded that high CO(2) concentration favours more tree aboveground biomass growth than underground biomass growth under favorable soil water conditions. And CO(2) enrichment enhanced lateral growth of shoot and vertical growth of root. The responses of plants to elevated CO(2) depend on soil water availability, and plants may benefit more from CO(2) enrichment with sufficient water supply. PMID:16532530

  2. Low Red Blood Cell Vitamin C Concentrations Induce Red Blood Cell Fragility: A Link to Diabetes Via Glucose, Glucose Transporters, and Dehydroascorbic Acid

    PubMed Central

    Tu, Hongbin; Li, Hongyan; Wang, Yu; Niyyati, Mahtab; Wang, Yaohui; Leshin, Jonathan; Levine, Mark

    2015-01-01

    Strategies to prevent diabetic microvascular angiopathy focus on the vascular endothelium. Because red blood cells (RBCs) are less deformable in diabetes, we explored an original concept linking decreased RBC deformability to RBC ascorbate and hyperglycemia. We characterized ascorbate concentrations from human and mouse RBCs and plasma, and showed an inverse relationship between RBC ascorbate concentrations and deformability, measured by osmotic fragility. RBCs from ascorbate deficient mice were osmotically sensitive, appeared as spherocytes, and had decreased β-spectrin. These aberrancies reversed with ascorbate repletion in vivo. Under physiologic conditions, only ascorbate's oxidation product dehydroascorbic acid (DHA), a substrate for facilitated glucose transporters, was transported into mouse and human RBCs, with immediate intracellular reduction to ascorbate. In vitro, glucose inhibited entry of physiologic concentrations of dehydroascorbic acid into mouse and human RBCs. In vivo, plasma glucose concentrations in normal and diabetic mice and humans were inversely related to respective RBC ascorbate concentrations, as was osmotic fragility. Human RBC β-spectrin declined as diabetes worsened. Taken together, hyperglycemia in diabetes produced lower RBC ascorbate with increased RBC rigidity, a candidate to drive microvascular angiopathy. Because glucose transporter expression, DHA transport, and its inhibition by glucose differed for mouse versus human RBCs, human experimentation is indicated. PMID:26870799

  3. Arsenic concentrations, related environmental factors, and the predicted probability of elevated arsenic in groundwater in Pennsylvania

    USGS Publications Warehouse

    Gross, Eliza L.; Low, Dennis J.

    2013-01-01

    Analytical results for arsenic in water samples from 5,023 wells obtained during 1969–2007 across Pennsylvania were compiled and related to other associated groundwater-quality and environmental factors and used to predict the probability of elevated arsenic concentrations, defined as greater than or equal to 4.0 micrograms per liter (µg/L), in groundwater. Arsenic concentrations of 4.0 µg/L or greater (elevated concentrations) were detected in 18 percent of samples across Pennsylvania; 8 percent of samples had concentrations that equaled or exceeded the U.S. Environmental Protection Agency’s drinking-water maximum contaminant level of 10.0 µg/L. The highest arsenic concentration was 490.0 µg/L. Comparison of arsenic concentrations in Pennsylvania groundwater by physiographic province indicates that the Central Lowland physiographic province had the highest median arsenic concentration (4.5 µg/L) and the highest percentage of sample records with arsenic concentrations greater than or equal to 4.0 µg/L (59 percent) and greater than or equal to 10.0 µg/L (43 percent). Evaluation of four major aquifer types (carbonate, crystalline, siliciclastic, and surficial) in Pennsylvania showed that all types had median arsenic concentrations less than 4.0 µg/L, and the highest arsenic concentration (490.0 µg/L) was in a siliciclastic aquifer. The siliciclastic and surficial aquifers had the highest percentage of sample records with arsenic concentrations greater than or equal to 4.0 µg/L and 10.0 µg/L. Elevated arsenic concentrations were associated with low pH (less than or equal to 4.0), high pH (greater than or equal to 8.0), or reducing conditions. For waters classified as anoxic (405 samples), 20 percent of sampled wells contained water with elevated concentrations of arsenic; for waters classified as oxic (1,530 samples) only 10 percent of sampled wells contained water with elevated arsenic concentrations. Nevertheless, regardless of the reduction

  4. Daily irradiance and feedback inhibition of photosynthesis at elevated carbon dioxide concentration in Brassica oleracea

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The fundamental cause of down-regulation of photosynthesis at elevated carbon dioxide concentration is thought to be a slower rate of utilization of carbohydrates than their stimulated rate of production, but there are few studies directly supporting this idea. We hypothesized that down-regulation w...

  5. Physical and chemical changes in whey protein concentrate stored at elevated temperature and humidity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The chemistry of whey protein concentrate (WPC) under adverse storage conditions was monitored to provide information on shelf life in hot, humid areas. WPC34 (34.9 g protein/100 g) and WPC80 (76.8 g protein/100 g) were stored for up to 18 mo under ambient conditions and at elevated temperature and...

  6. SGLT1 activity in lung alveolar cells of diabetic rats modulates airway surface liquid glucose concentration and bacterial proliferation.

    PubMed

    Oliveira, Tales Lyra; Candeia-Medeiros, Návylla; Cavalcante-Araújo, Polliane M; Melo, Igor Santana; Fávaro-Pípi, Elaine; Fátima, Luciana Alves; Rocha, Antônio Augusto; Goulart, Luiz Ricardo; Machado, Ubiratan Fabres; Campos, Ruy R; Sabino-Silva, Robinson

    2016-01-01

    High glucose concentration in the airway surface liquid (ASL) is an important feature of diabetes that predisposes to respiratory infections. We investigated the role of alveolar epithelial SGLT1 activity on ASL glucose concentration and bacterial proliferation. Non-diabetic and diabetic rats were intranasally treated with saline, isoproterenol (to increase SGLT1 activity) or phlorizin (to decrease SGLT1 activity); 2 hours later, glucose concentration and bacterial proliferation (methicillin-resistant Sthaphylococcus aureus, MRSA and Pseudomonas aeruginosa, P. aeruginosa) were analyzed in bronchoalveolar lavage (BAL); and alveolar SGLT1 was analyzed by immunohistochemistry. BAL glucose concentration and bacterial proliferation increased in diabetic animals: isoproterenol stimulated SGLT1 migration to luminal membrane, and reduced (50%) the BAL glucose concentration; whereas phlorizin increased the BAL glucose concentration (100%). These regulations were accompanied by parallel changes of in vitro MRSA and P. aeruginosa proliferation in BAL (r = 0.9651 and r = 0.9613, respectively, Pearson correlation). The same regulations were observed in in vivo P. aeruginosa proliferation. In summary, the results indicate a relationship among SGLT1 activity, ASL glucose concentration and pulmonary bacterial proliferation. Besides, the study highlights that, in situations of pulmonary infection risk, such as in diabetic subjects, increased SGLT1 activity may prevent bacterial proliferation whereas decreased SGLT1 activity can exacerbate it. PMID:26902517

  7. SGLT1 activity in lung alveolar cells of diabetic rats modulates airway surface liquid glucose concentration and bacterial proliferation

    PubMed Central

    Oliveira, Tales Lyra; Candeia-Medeiros, Návylla; Cavalcante-Araújo, Polliane M.; Melo, Igor Santana; Fávaro-Pípi, Elaine; Fátima, Luciana Alves; Rocha, Antônio Augusto; Goulart, Luiz Ricardo; Machado, Ubiratan Fabres; Campos, Ruy R.; Sabino-Silva, Robinson

    2016-01-01

    High glucose concentration in the airway surface liquid (ASL) is an important feature of diabetes that predisposes to respiratory infections. We investigated the role of alveolar epithelial SGLT1 activity on ASL glucose concentration and bacterial proliferation. Non-diabetic and diabetic rats were intranasally treated with saline, isoproterenol (to increase SGLT1 activity) or phlorizin (to decrease SGLT1 activity); 2 hours later, glucose concentration and bacterial proliferation (methicillin-resistant Sthaphylococcus aureus, MRSA and Pseudomonas aeruginosa, P. aeruginosa) were analyzed in bronchoalveolar lavage (BAL); and alveolar SGLT1 was analyzed by immunohistochemistry. BAL glucose concentration and bacterial proliferation increased in diabetic animals: isoproterenol stimulated SGLT1 migration to luminal membrane, and reduced (50%) the BAL glucose concentration; whereas phlorizin increased the BAL glucose concentration (100%). These regulations were accompanied by parallel changes of in vitro MRSA and P. aeruginosa proliferation in BAL (r = 0.9651 and r = 0.9613, respectively, Pearson correlation). The same regulations were observed in in vivo P. aeruginosa proliferation. In summary, the results indicate a relationship among SGLT1 activity, ASL glucose concentration and pulmonary bacterial proliferation. Besides, the study highlights that, in situations of pulmonary infection risk, such as in diabetic subjects, increased SGLT1 activity may prevent bacterial proliferation whereas decreased SGLT1 activity can exacerbate it. PMID:26902517

  8. Aqueous Fraction of Beta vulgaris Ameliorates Hyperglycemia in Diabetic Mice due to Enhanced Glucose Stimulated Insulin Secretion, Mediated by Acetylcholine and GLP-1, and Elevated Glucose Uptake via Increased Membrane Bound GLUT4 Transporters

    PubMed Central

    Kabir, Ashraf Ul; Samad, Mehdi Bin; Ahmed, Arif; Jahan, Mohammad Rajib; Akhter, Farjana; Tasnim, Jinat; Hasan, S. M. Nageeb; Sayfe, Sania Sarker; Hannan, J. M. A.

    2015-01-01

    Background The study was designed to investigate the probable mechanisms of anti-hyperglycemic activity of B. Vulgaris. Methodology/Principal Findings Aqueous fraction of B. Vulgaris extract was the only active fraction (50mg/kg). Plasma insulin level was found to be the highest at 30 mins after B. Vulgaris administration at a dose of 200mg/kg. B. Vulgaris treated mice were also assayed for plasma Acetylcholine, Glucagon Like Peptide-1 (GLP-1), Gastric Inhibitory Peptide (GIP), Vasoactive Intestinal Peptide, Pituitary Adenylate Cyclase-Activating Peptide (PACAP), Insulin Like Growth Factor-1 (IGF-1), Pancreatic Polypeptides (PP), and Somatostatin, along with the corresponding insulin levels. Plasma Acetylcholine and GLP-1 significantly increased in B. Vulgaris treated animals and were further studied. Pharmacological enhancers, inhibitors, and antagonists of Acetylcholine and GLP-1 were also administered to the test animals, and corresponding insulin levels were measured. These studies confirmed the role of acetylcholine and GLP-1 in enhanced insulin secretion (p<0.05). Principal signaling molecules were quantified in isolated mice islets for the respective pathways to elucidate their activities. Elevated concentrations of Acetylcholine and GLP-1 in B. Vulgaris treated mice were found to be sufficient to activate the respective pathways for insulin secretion (p<0.05). The amount of membrane bound GLUT1 and GLUT4 transporters were quantified and the subsequent glucose uptake and glycogen synthesis were assayed. We showed that levels of membrane bound GLUT4 transporters, glucose-6-phosphate in skeletal myocytes, activity of glycogen synthase, and level of glycogen deposited in the skeletal muscles all increased (p<0.05). Conclusion Findings of the present study clearly prove the role of Acetylcholine and GLP-1 in the Insulin secreting activity of B. Vulgaris. Increased glucose uptake in the skeletal muscles and subsequent glycogen synthesis may also play a part in

  9. Increasing glucose concentrations and prevalence of diabetes mellitus in northern Sweden, 1990–2007

    PubMed Central

    Lindahl, Bernt; Stenlund, Hans; Norberg, Margareta

    2010-01-01

    Background The prevalence of diabetes in the world is projected to rise from 2.8% in the year 2000 to 4.4% in 2030, an increase suggesting an ongoing global epidemic of diabetes. Objective To examine time trends in fasting and 2-h glucose concentrations, prevalence and 10-year cumulative incidence of diabetes, and the role of education in these trends. Design Each year the Västerbotten Intervention Programme invites all 40, 50, and 60-year-old individuals to a health survey, which includes a cardiovascular risk factor screening and oral glucose tolerance test. The cross-sectional part of the study is based on health examinations conducted between 1990 and 2007 (n = 102,822). The prospective subset (panel dataset) of the study is based on individuals who have had two health examinations 10 years apart and were not defined as having diabetes at their first health examination (n = 23,546). Results Between 1990 and 2007, the mean population fasting glucose concentration increased 0.5 mmol/L. Comparing the prevalence in 1990–1995 with 2002–2007 demonstrated a significant 44% increase in men (p < 0.001) and a significant 17% increase in women (p<0.001). Socioeconomic status, here represented by education, clearly influenced both prevalence and incidence of diabetes and glucose concentration. In all time periods and in all age groups, individuals with low education were more likely to have or get diabetes. The 10-year risk of developing diabetes was four to five times higher in the oldest age group (50–60 years) compared with the youngest (30–40 years). A 30% reduction in the 10-year risk of developing diabetes was found in women (p<0.001) between 2000–2003 and 2004–2007. Conclusions Despite a clear increase in glucose concentrations and diabetes prevalence between 1990 and 2007, especially in men, there was a decline in the 10-year risk of developing diabetes in women between 2000–2003 and 2004–2007. PMID:21042431

  10. Post-glucose-load urinary C-peptide and glucose concentration obtained during OGTT do not affect oral minimal model-based plasma indices.

    PubMed

    Jainandunsing, Sjaam; Wattimena, J L Darcos; Rietveld, Trinet; van Miert, Joram N I; Sijbrands, Eric J G; de Rooij, Felix W M

    2016-05-01

    The purpose of this study was to investigate how renal loss of both C-peptide and glucose during oral glucose tolerance test (OGTT) relate to and affect plasma-derived oral minimal model (OMM) indices. All individuals were recruited during family screening between August 2007 and January 2011 and underwent a 3.5-h OGTT, collecting nine plasma samples and urine during OGTT. We obtained the following three subgroups: normoglycemic, at risk, and T2D. We recruited South Asian and Caucasian families, and we report separate analyses if differences occurred. Plasma glucose, insulin, and C-peptide concentrations were analyzed as AUCs during OGTT, OMM estimate of renal C-peptide secretion, and OMM beta-cell and insulin sensitivity indices were calculated to obtain disposition indices. Post-glucose load glucose and C-peptide in urine were measured and related to plasma-based indices. Urinary glucose corresponded well with plasma glucose AUC (Cau r = 0.64, P < 0.01; SA r = 0.69, P < 0.01), S I (Cau r = -0.51, P < 0.01; SA r = -0.41, P < 0.01), Φ dynamic (Cau r = -0.41, P < 0.01; SA r = -0.57, P < 0.01), and Φ oral (Cau r = -0.61, P < 0.01; SA r = -0.73, P < 0.01). Urinary C-peptide corresponded well to plasma C-peptide AUC (Cau r = 0.45, P < 0.01; SA r = 0.33, P < 0.05) and OMM estimate of renal C-peptide secretion (r = 0.42, P < 0.01). In general, glucose excretion plasma threshold for the presence of glucose in urine was ~10-10.5 mmol L(-1) in non-T2D individuals, but not measurable in T2D individuals. Renal glucose secretion during OGTT did not influence OMM indices in general nor in T2D patients (renal clearance range 0-2.1 %, with median 0.2 % of plasma glucose AUC). C-indices of urinary glucose to detect various stages of glucose intolerance were excellent (Cau 0.83-0.98; SA 0.75-0.89). The limited role of renal glucose secretion validates the neglecting of urinary glucose secretion in kinetic models of glucose

  11. Noncontact speckle-based optical sensor for detection of glucose concentration using magneto-optic effect

    NASA Astrophysics Data System (ADS)

    Ozana, Nisan; Beiderman, Yevgeny; Anand, Arun; Javidi, Baharam; Polani, Sagi; Schwarz, Ariel; Shemer, Amir; Garcia, Javier; Zalevsky, Zeev

    2016-06-01

    We experimentally verify a speckle-based technique for noncontact measurement of glucose concentration in the bloodstream. The final device is intended to be a single wristwatch-style device containing a laser, a camera, and an alternating current (ac) electromagnet generated by a solenoid. The experiments presented are performed in vitro as proof of the concept. When a glucose substance is inserted into a solenoid generating an ac magnetic field, it exhibits Faraday rotation, which affects the temporal changes of the secondary speckle pattern distributions. The temporal frequency resulting from the ac magnetic field was found to have a lock-in amplification role, which increased the observability of the relatively small magneto-optic effect. Experimental results to support the proposed concept are presented.

  12. Effect of guar crispbread with cereal products and leguminous seeds on blood glucose concentrations of diabetics.

    PubMed

    Jenkins, D J; Wolever, T M; Taylor, R H; Barker, H M; Fielden, H; Jenkins, A L

    1980-11-01

    To compare the effect on blood glucose concentrations of guar incorporated into crispbreads with that of unprocessed high-fibre foods groups of four to six diabetics took a total of seven test breakfasts on separate days. By comparison with a breakfast of wholemeal bread and cheese, guar crispbread combined with bread reduced the area under the glucose response curve to 51% (p < 0.05); bread and soya beans reduced the area to 65% (p < 0.05); guar crispbread with soya beans to 25% (p < 0.002); and soya beans with lentils to 29% (p < 0.002). Porridge and cornflake breakfasts showed no difference. The favourable results with leguminous seeds may not make such meals more acceptable than meals of guar products, but a combination of leguminous seeds and guar may allow smaller and more acceptable amounts of both to be used. PMID:6253021

  13. Obese gene expression: reduction by fasting and stimulation by insulin and glucose in lean mice, and persistent elevation in acquired (diet-induced) and genetic (yellow agouti) obesity.

    PubMed Central

    Mizuno, T M; Bergen, H; Funabashi, T; Kleopoulos, S P; Zhong, Y G; Bauman, W A; Mobbs, C V

    1996-01-01

    Mutations in the obese (ob) gene lead to obesity. This gene has been recently cloned, but the factors regulating its expression have not been elucidated. To address the regulation of the ob gene with regard to body weight and nutritional factors, Northern blot analysis was used to assess ob mRNA in adipose tissue from mice [lean, obese due to diet, or genetically (yellow agouti) obese] under different nutritional conditions. ob mRNA was elevated in both forms of obesity, compared to lean controls, correlated with elevations in plasma insulin and body weight, but not plasma glucose. In lean C57BL/6J mice, but not in mice with diet-induced obesity, ob mRNA decreased after a 48-hr fast. Similarly, in lean C57BL/6J controls, but not in obese yellow mice, i.p. glucose injection significantly increased ob mRNA. For up to 30 min after glucose injection, ob mRNA in lean mice significantly correlated with plasma glucose, but not with plasma insulin. In a separate study with only lean mice, ob mRNA was inhibited >90% by fasting, and elevated approximately 2-fold 30 min after i.p. injection of either glucose or insulin. These results suggest that in lean animals glucose and insulin enhance ob gene expression. In contrast to our results in lean mice, in obese animals ob mRNA is elevated and relatively insensitive to nutritional state, possibly due to chronic exposure to elevated plasma insulin and/or glucose. Images Fig. 1 Fig. 4 PMID:8622953

  14. Chronic Superantigen Exposure Induces Systemic Inflammation, Elevated Bloodstream Endotoxin, and Abnormal Glucose Tolerance in Rabbits: Possible Role in Diabetes

    PubMed Central

    Vu, Bao G.; Stach, Christopher S.; Kulhankova, Katarina; Salgado-Pabón, Wilmara; Klingelhutz, Aloysius J.

    2015-01-01

    ABSTRACT Excessive weight and obesity are associated with the development of diabetes mellitus type 2 (DMII) in humans. They also pose high risks of Staphylococcus aureus colonization and overt infections. S. aureus causes a wide range of severe illnesses in both healthy and immunocompromised individuals. Among S. aureus virulence factors, superantigens are essential for pathogenicity. In this study, we show that rabbits that are chronically exposed to S. aureus superantigen toxic shock syndrome toxin-1 (TSST-1) experience impaired glucose tolerance, systemic inflammation, and elevated endotoxin levels in the bloodstream, all of which are common findings in DMII. Additionally, such DMII-associated findings are also seen through effects of TSST-1 on isolated adipocytes. Collectively, our findings suggest that chronic exposure to S. aureus superantigens facilitates the development of DMII, which may lead to therapeutic targeting of S. aureus and its superantigens. PMID:25714716

  15. High glucose concentrations attenuate hypoxia-inducible factor-1{alpha} expression and signaling in non-tumor cells

    SciTech Connect

    Dehne, Nathalie; Bruene, Bernhard

    2010-04-15

    Hypoxia-inducible factor (HIF) is the major transcription factor mediating adaption to hypoxia e.g. by enhancing glycolysis. In tumor cells, high glucose concentrations are known to increase HIF-1{alpha} expression even under normoxia, presumably by enhancing the concentration of tricarboxylic acid cycle intermediates, while reactions of non-tumor cells are not well defined. Therefore, we analyzed cellular responses to different glucose concentrations in respect to HIF activation comparing tumor to non-tumor cells. Using cells derived from non-tumor origin, we show that HIF-1{alpha} accumulation was higher under low compared to high glucose concentrations. Low glucose allowed mRNA expression of HIF-1 target genes like adrenomedullin. Transfection of C{sub 2}C{sub 12} cells with a HIF-1{alpha} oxygen-dependent degradation domaine-GFP fusion protein revealed that prolyl hydroxylase (PHD) activity is impaired at low glucose concentrations, thus stabilizing the fusion protein. Mechanistic considerations suggested that neither O{sub 2} redistribution nor an altered redox state explains impaired PHD activity in the absence of glucose. In order to affect PHD activity, glucose needs to be metabolized. Amino acids present in the medium also diminished HIF-1{alpha} expression, while the addition of fatty acids did not. This suggests that glucose or amino acid metabolism increases oxoglutarate concentrations, which enhances PHD activity in non-tumor cells. Tumor cells deprived of glutamine showed HIF-1{alpha} accumulation in the absence of glucose, proposing that enhanced glutaminolysis observed in many tumors enables these cells to compensate reduced oxoglutarate production in the absence of glucose.

  16. Elevated Concentration of Defensins in Hepatitis C Virus-Infected Patients

    PubMed Central

    Mattar, Ehab H.; Almehdar, Hussein A.; AlJaddawi, Abdullah A.; Abu Zeid, Isam ElDin M.; Redwan, Elrashdy M.

    2016-01-01

    Hepatitis C virus (HCV) is the major etiological agent of human non-A and non-B hepatitis, affecting around 180 million people worldwide. Defensins, small cysteine-rich cationic peptides, are shown to have potent antibacterial, antiviral, and antifungal properties. Defensins can be found in both normal and microbial infected patients, at variable concentrations. Notably, viral infections are often associated with elevated concentrations of defensins. The current study aimed to estimate the concentrations of total, α-, and β-defensins in serum taken from normal and HCV-infected patients. 12 healthy (noninfected) and 34 HCV-infected patients were enrolled. Standardized immunoassay kits were used to obtain serum concentrations of defensins. The obtained results were calibrated against kit standard reagents. Total defensin concentrations in HCV-infected patients were significantly higher (2- to 105-fold) compared to healthy individuals. The concentrations of α-defensins were also significantly elevated in the HCV-infected patients (31–1398 ng/50 μL). However, concentrations of β-defensins ranged from 44.5 ng/50 μL to 1056 ng/50 μL. The results did not reveal differences in serum defensin concentration between male and female HCV-infected patients. A-defensin concentration of ≥250 ng/50 μL was found to contain more β-defensins than total defensins and α-defensins. This study concludes, for the first time, that serum defensin levels are elevated in HCV-infected patients. PMID:27413763

  17. The effect of insulin on plasma glucose concentrations, expression of hepatic glucose transporters and key gluconeogenic enzymes during the perinatal period in broiler chickens.

    PubMed

    Franssens, Lies; Lesuisse, Jens; Wang, Yufeng; Willems, Els; Willemsen, Hilke; Koppenol, Astrid; Guo, Xiaoquan; Buyse, Johan; Decuypere, Eddy; Everaert, Nadia

    2016-06-01

    Chickens have blood glucose concentrations that are twofold higher than those observed in mammals. Moreover, the insulin sensitivity seems to decrease with postnatal age in both broiler and layer chickens. However, little is known about the response of insulin on plasma glucose concentrations and mRNA abundance of hepatic glucose transporters 1, 2, 3, 8, 9 and 12 (GLUT1, 2, 3, 8, 9 and 12) and three regulatory enzymes of the gluconeogenesis, phosphoenolpyruvate carboxykinase 1 and 2 (PCK1 and 2) or fructose-1,6-biphosphatase 1 (FBP1) in chicks during the perinatal period. In the present study, broiler embryos on embryonic day (ED)16, ED18 or newly-hatched broiler chicks were injected intravenously with bovine insulin (1μg/g body weight (BW)) to examine plasma glucose response and changes in hepatic mRNA abundance of the GLUTs, PCK1 and 2 and FBP1. Results were compared with a non-treated control group and a saline-injected sham group. Plasma glucose levels of insulin-treated ED18 embryos recovered faster from their minimum level than those of insulin-treated ED16 embryos or newly-hatched chicks. In addition, at the minimum plasma glucose level seven hours post-injection (PI), hepatic GLUT2, FBP1 and PCK2 mRNA abundance was decreased in insulin-injected embryos, compared to sham and control groups, being most pronounced when insulin injection occurred on ED16. PMID:26723190

  18. Concentration of rutin model solutions from their mixtures with glucose using ultrafiltration.

    PubMed

    Wei, Swallow; Hossain, Md M; Saleh, Zaid S

    2010-01-01

    Separation of polyphenolic phytochemical compounds from their mixtures with sugars is necessary to produce an added-value sugar-reduced extract with high biological activity from fruit juice processing industry waste streams. The separation characteristics of a binary mixture of rutin and glucose using a Pellicon-2 regenerated cellulose ultrafiltration membrane with an area of 0.1 m(2) having nominal MWCO of 1,000 Da were investigated, to demonstrate the separation of phenolic compounds from sugars. The effects of the operating variables-transmembrane pressure, feed solution temperature and pH, initial feed concentration and feed flow rate-on the permeate flux and enrichment of rutin, were determined. The permeate flux increased with the increase in transmembrane pressure up to a certain limit and after that the flux remained more or less constant. The optimum transmembrane pressure was within 4-5 bar. The flux increased with the increase in feed solution temperature because of reduced feed viscosity, and better solubility. The concentration of rutin was optimum at lower temperature (30 degrees C), with an enrichment factor of 1.3. The effect of pH on permeate flux was less obvious. Lowering the feed solution pH increased the retention of rutin and the optimum separation was obtained within pH 3-4. The permeate flux decreased with the increase in feed concentration of rutin (concentration range 0.1-0.5 g/L). The enrichment of rutin was significant in the glucose concentration range 0.35-0.5 g/L. The feed flow rate had a significant effect on the flux and separation characteristics. Higher cross-flow through the membrane reduced the fouling by providing a shear force to sweep away deposited materials from the membrane surface. At high feed flow rate, more rutin was retained by the membrane with less sugar permeating through. The optimum feed flow rate was 1.5 L/min. For the separation of rutin (in the retentate) and glucose (in the permeate), the best results were

  19. Estimating the Probability of Elevated Nitrate Concentrations in Ground Water in Washington State

    USGS Publications Warehouse

    Frans, Lonna M.

    2008-01-01

    Logistic regression was used to relate anthropogenic (manmade) and natural variables to the occurrence of elevated nitrate concentrations in ground water in Washington State. Variables that were analyzed included well depth, ground-water recharge rate, precipitation, population density, fertilizer application amounts, soil characteristics, hydrogeomorphic regions, and land-use types. Two models were developed: one with and one without the hydrogeomorphic regions variable. The variables in both models that best explained the occurrence of elevated nitrate concentrations (defined as concentrations of nitrite plus nitrate as nitrogen greater than 2 milligrams per liter) were the percentage of agricultural land use in a 4-kilometer radius of a well, population density, precipitation, soil drainage class, and well depth. Based on the relations between these variables and measured nitrate concentrations, logistic regression models were developed to estimate the probability of nitrate concentrations in ground water exceeding 2 milligrams per liter. Maps of Washington State were produced that illustrate these estimated probabilities for wells drilled to 145 feet below land surface (median well depth) and the estimated depth to which wells would need to be drilled to have a 90-percent probability of drawing water with a nitrate concentration less than 2 milligrams per liter. Maps showing the estimated probability of elevated nitrate concentrations indicated that the agricultural regions are most at risk followed by urban areas. The estimated depths to which wells would need to be drilled to have a 90-percent probability of obtaining water with nitrate concentrations less than 2 milligrams per liter exceeded 1,000 feet in the agricultural regions; whereas, wells in urban areas generally would need to be drilled to depths in excess of 400 feet.

  20. Angelica sinensis polysaccharide regulates glucose and lipid metabolism disorder in prediabetic and streptozotocin-induced diabetic mice through the elevation of glycogen levels and reduction of inflammatory factors.

    PubMed

    Wang, Kaiping; Cao, Peng; Shui, Weizhi; Yang, Qiuxiang; Tang, Zhuohong; Zhang, Yu

    2015-03-01

    The present study was designed to evaluate the potential hypoglycemic and hypolipidemic effects of Angelica sinensis polysaccharide (ASP), purified from the fresh roots of Angelica sinensis (AS), in prediabetic and streptozotocin (STZ)-induced diabetic BALB/c mice. It was observed that fasting blood glucose (FBG) levels in both models were reduced after a 4-week oral administration of ASP or metformin, and abnormal fasting serum insulin (FINS) concentrations were ameliorated as well. Moreover, the homeostasis model assessment-insulin resistance (HOMA-IR) index was decreased strikingly and body weight (BW) was reduced significantly in prediabetic mice after treatment with ASP. In addition, ASP also contributed to improving the dyslipidemia conditions. Elevated serum total cholesterol (TC) or triglyceride (TG) concentrations were reduced after treatment with ASP in prediabetic mice or STZ-induced diabetic mice. Meanwhile, hepatic glycogen (HG) and muscle glycogen (MG) concentrations were increased while insulin resistance (IR)-related inflammatory factors IL-6 and TNF-α in serum were reduced in STZ-induced diabetic mice. Histopathological examination indicated that the impaired pancreatic/hepatic tissues or adipose tissues were effectively restored in STZ-induced diabetic mice or prediabetic mice after the ASP treatment. Taken together, these results revealed that ASP efficiently exerted hypoglycemic and hypolipidemic benefits, and its potential effect was associated with the amelioration of IR. ASP can be applied in the prevention and treatment of diabetes. PMID:25630053

  1. The effect of glucose concentration on insulin-induced 3T3-L1 adipose cell differentiation.

    PubMed

    Gagnon, A; Sorisky, A

    1998-03-01

    We examined the effect of glucose concentration on insulin-induced 3T3-L1 adipose cell differentiation. Oil Red O staining of neutral lipid, cellular triglyceride mass, and glycerol phosphate dehydrogenase (GPDH) activity, were greater in 3T3-L1 cells cultured at 5 mM vs. 25 mM glucose. GPDH activity was 2- to 4-fold higher at 5 mM vs. 25 mM glucose over a range of insulin concentrations (0.1 to 100 nM). Insulin-stimulated tyrosine phosphorylation of insulin receptor substrate-1 (IRS-1) was 1.7-fold greater, and insulin-stimulated phosphoinositide 3-kinase association with IRS-1 was 2.3-fold higher, at 5 mM vs. 25 mM glucose. These effects of glucose were not caused by alterations in IRS-1 mass or cell-surface insulin binding. In preadipose cells at 5 mM glucose, expression of the leukocyte antigen-related (LAR) protein tyrosine phosphatase (negative regulator of insulin signaling) was 63% of the level at 25 mM glucose. Our data demonstrate that glucose concentration affects insulin-induced 3T3-L1 adipose cell differentiation as well as differentiation-directed insulin signaling pathways. Alterations in LAR expression potentially may be involved in modulating these responses. PMID:9545023

  2. Heterogeneity in multicell spheroids induced by alterations in the external oxygen and glucose concentration

    SciTech Connect

    Freyer, J.P.

    1981-01-01

    Multicell tumor spheroids are currently being used as in vitro models for investigations of tumor therapy, based on the concept that spheroids exhibit many of the growth characteristics and cell subpopulations of tumors in vivo. At present, the factors which regulate cell proliferation, clonogenicity and viability in spheroids are unknown, as are the effects of alterations in these critical factors on therapeutic results. The symmetrical structure of the EMT6/Ro spheroid and the ease of manipulating the external environment are key features of this spheroid system which are used to investigate the role of oxygen and glucose in the control of spheroid growth and the development of cell subpopulations. A technique is developed for selectivity dissociating a spheroid population into fractions of cells originating from known locations in the spheroid structure. Characterization of these cell subpopulations demonstrates that outer cells are similar to an exponential cell population, while inner region cells are not proliferating and have a reduced cell volume and clonogenic capacity. Oxygen and glucose concentrations at critical depths in the spheroid were determined. It is concluded that the oxygen and glucose supply to cells in spheroids is critical in determining the initial onset of central necrosis. 217 references, 32 figures, 15 tables. (ACR)

  3. [Effects of elevated CO2 concentration on the quality of agricultural products: a review].

    PubMed

    Chai, Ru-shan; Niu, Yao-fang; Zhu, Li-qing; Wang, Huan; Zhang, Yong-song

    2011-10-01

    The increasing concentration of atmospheric CO2 and the nutritional quality of human diets are the two important issues we are facing. At present, the atmospheric CO2 concentration is about 380 micromol mol(-1), and to be reached 550 micromol mol(-1) by 2050. A great deal of researches indicated that the quality of agricultural products is not only determined by inherited genes, but also affected by the crop growth environmental conditions. This paper summarized the common methods adopted at home and abroad for studying the effects of CO2 enrichment on the quality of agricultural products, and reviewed the research advances in evaluating the effects of elevated CO2 on the quality of rice, wheat, soybean, and vegetables. Many experimental results showed that elevated CO2 concentration causes a decrease of protein content in the grains of staple food crops and an overall decreasing trend of trace elements contents in the crops, but improves the quality of vegetable products to some extent. Some issues and future directions regarding the effects of elevated CO2 concentration on the quality of agricultural products were also discussed, based on the present status of related researches. PMID:22263486

  4. Elevated concentrations of 1-hydroxypyrene in schoolchildren during winter in Christchurch, New Zealand.

    PubMed

    Cavanagh, Jo-Anne E; Brown, Leslie; Trought, Katherine; Kingham, Simon; Epton, Michael J

    2007-03-01

    Particulate air pollution is significantly elevated during the winter in Christchurch, New Zealand, largely attributable to use of wood burners for domestic home heating, topography, and meteorological conditions. Polycyclic aromatic hydrocarbons (PAHs) are a key component of airborne particulate matter (PM) and urinary 1-hydroxypyrene (1-OHP) has previously been used to assess exposure of people to PAHs. We examined urinary 1-OHP in Christchurch male non-smoking schoolchildren (12-18 yr) on two occasions after high pollution events (48 and 72 microg PM(10)/m(3) 24-h average) and two occasions during periods of low pollution (19 and 12 microg PM(10)/m(3)). Concentrations of urinary 1-OHP were significantly elevated in the students during high pollution events (median (mean+/-SD) 0.043 (0.051+/-0.032) and 0.042 (0.060+/-0.092) micromol OHP/mol creatinine respectively) compared with low pollution periods (median (mean+/-SD) 0.019 (0.026+/-0.032) and 0.025 (0.028+/-0.018) micromol/mol creatinine respectively). The observed 1-OHP concentrations are at the lower end of those determined in children and non-occupationally exposed adults in international studies and suggest a generally low exposure to PAHs. The increased urinary 1-OHP concentrations following nights of elevated particulate concentrations in ambient air suggest increased exposure to ambient air pollution during winter time, and could potentially be used as a biomarker of exposure in this population. PMID:17257655

  5. [Effects of elevated CO2 concentration on physiological characters of three dwarf ornamental bamboo species].

    PubMed

    Zhuang, Ming-Hao; Chen, Shuang-Lin; Li, Ying-Chun; Guo, Zi-Wu; Yang, Qing-Ping

    2013-09-01

    By using open-top chambers (OTCs) to simulate the scenes of elevated CO2 concentrations [500 micromol x mol(-1) (T1) and 700 micromol x mol(-1) (T2)], and taking ambient atmospheric CO2 concentration as the control (CK), this paper studied the effects of elevated CO2 concentration on the lipid peroxidation and anti-oxidation enzyme system in Indocalamus decorus, Pleioblastus kongosanensis, and Sasa glabra leaves. After 103 days treatment, the O2(-)* and MDA contents, relative electron conduction, and soluble sugar content in the three dwarf ornamental bamboo species leaves in T1 had no obvious change, but the activities of anti-oxidation enzymes (SOD, POD, CAT, and APX) changed to a certain extent. In T2, the MDA content and relative electron conduction had no obvious change, but the O2(-)* and soluble sugar contents and the anti-oxidation enzymes activities changed obviously. The adaptation capacity of the three bamboo species to elevated CO2 concentration was in the order of I. decorus > P. kongosanensis > S. glabra. PMID:24417095

  6. Cytokine profile in cases with premature elevation of progesterone serum concentrations during ovarian stimulation.

    PubMed

    Nikolettos, N; Asimakopoulos, B; Köster, F; Schöpper, B; Schulz, Ch; Caglar, G S; Efthimiadou, A; Pagonopoulou, O; Diedrich, K; Al-Hasani, S

    2008-01-01

    The aim of this study was to investigate the concentrations of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), leptin, tumor necrosis factor-alpha, interleukin (IL)-1beta and IL-6, in cycles with a premature rise of serum progesterone. 25 intracytoplasmic sperm injection (ICSI) cycles with (Group 1) and 25 ICSI cycles without a premature progesterone elevation (Group 2) were included. The cut-off value of serum progesterone on the day of human chorionic gonadotropin (hCG) administration was 0.9 ng/ml. The indication for ICSI was male factor infertility exclusively. On the day of hCG injection, serum IL-6, VEGF and bFGF were significantly higher in Group 1 (7.7+/-24.5 pg/ml, 290.2+/-161.4 pg/ml and 15.7+/-8.2 ng/ml respectively) than in Group 2 (1.7+/-0.7 pg/ml, 175.2+/-92.1 pg/ml, and 9+/-1.6 ng/ml respectively). On the day of follicular puncture, serum cytokine concentrations were similar in the two groups. IL-6 intrafollicular concentrations were higher in Group 1 (14.7+/-20.7 pg/ml) than in Group 2 (9+/-9.3 pg/ml, p=0.031). There were no differences regarding the ICSI outcome. Patients with serum progesterone above 0.9 ng/ml, have elevated serum concentrations of IL-6, VEGF, and bFGF, as well as elevated intrafollicular concentrations of IL-6. The outcome of ICSI cycles is not associated with premature elevation of progesterone when the cut-off value is set at 0.9 ng/ml. PMID:17298206

  7. Elevated glucose and oligomeric β-amyloid disrupt synapses via a common pathway of aberrant protein S-nitrosylation

    PubMed Central

    Akhtar, Mohd Waseem; Sanz-Blasco, Sara; Dolatabadi, Nima; Parker, James; Chon, Kevin; Lee, Michelle S.; Soussou, Walid; McKercher, Scott R.; Ambasudhan, Rajesh; Nakamura, Tomohiro; Lipton, Stuart A.

    2016-01-01

    Metabolic syndrome (MetS) and Type 2 diabetes mellitus (T2DM) increase risk for Alzheimer's disease (AD). The molecular mechanism for this association remains poorly defined. Here we report in human and rodent tissues that elevated glucose, as found in MetS/T2DM, and oligomeric β-amyloid (Aβ) peptide, thought to be a key mediator of AD, coordinately increase neuronal Ca2+ and nitric oxide (NO) in an NMDA receptor-dependent manner. The increase in NO results in S-nitrosylation of insulin-degrading enzyme (IDE) and dynamin-related protein 1 (Drp1), thus inhibiting insulin and Aβ catabolism as well as hyperactivating mitochondrial fission machinery. Consequent elevation in Aβ levels and compromise in mitochondrial bioenergetics result in dysfunctional synaptic plasticity and synapse loss in cortical and hippocampal neurons. The NMDA receptor antagonist memantine attenuates these effects. Our studies show that redox-mediated posttranslational modification of brain proteins link Aβ and hyperglycaemia to cognitive dysfunction in MetS/T2DM and AD. PMID:26743041

  8. Elevated glucose and oligomeric β-amyloid disrupt synapses via a common pathway of aberrant protein S-nitrosylation.

    PubMed

    Akhtar, Mohd Waseem; Sanz-Blasco, Sara; Dolatabadi, Nima; Parker, James; Chon, Kevin; Lee, Michelle S; Soussou, Walid; McKercher, Scott R; Ambasudhan, Rajesh; Nakamura, Tomohiro; Lipton, Stuart A

    2016-01-01

    Metabolic syndrome (MetS) and Type 2 diabetes mellitus (T2DM) increase risk for Alzheimer's disease (AD). The molecular mechanism for this association remains poorly defined. Here we report in human and rodent tissues that elevated glucose, as found in MetS/T2DM, and oligomeric β-amyloid (Aβ) peptide, thought to be a key mediator of AD, coordinately increase neuronal Ca(2+) and nitric oxide (NO) in an NMDA receptor-dependent manner. The increase in NO results in S-nitrosylation of insulin-degrading enzyme (IDE) and dynamin-related protein 1 (Drp1), thus inhibiting insulin and Aβ catabolism as well as hyperactivating mitochondrial fission machinery. Consequent elevation in Aβ levels and compromise in mitochondrial bioenergetics result in dysfunctional synaptic plasticity and synapse loss in cortical and hippocampal neurons. The NMDA receptor antagonist memantine attenuates these effects. Our studies show that redox-mediated posttranslational modification of brain proteins link Aβ and hyperglycaemia to cognitive dysfunction in MetS/T2DM and AD. PMID:26743041

  9. Blood concentrations of lactate, glucose and corticosterone in dispersing hatchling sea turtles

    PubMed Central

    Pereira, Carla M.; Booth, David T.; Bradley, Adrian J.; Limpus, Colin J.

    2013-01-01

    Summary Natal dispersal of sea turtles is an energetically demanding activity that is fuelled primarily by aerobic metabolism. However, during intense exercise reptiles can use anaerobic metabolism to supplement their energy requirements. We assessed anaerobic metabolism in dispersing hatchling loggerhead and flatback turtles by measuring the concentrations of blood lactate during crawling and at different times during the first four hours of their frenzy swim. We also measured concentrations of blood glucose and corticosterone. Blood lactate (12.13 to 2.03 mmol/L), glucose (6.25 to 3.8 mmol/L) and corticosterone (8.13 to 2.01 ng/mL) concentrations decreased significantly over time in both loggerhead and flatback hatchlings and no significant differences were found between the species. These results indicate that anaerobic metabolism makes a significant contribution to the dispersal phase of hatchling sea turtles during the beach crawl and the first few hours of the frenzy swim. PMID:23336077

  10. Tomato–Pseudomonas syringae interactions under elevated CO2 concentration: the role of stomata

    PubMed Central

    Li, Xin; Sun, Zenghui; Shao, Shujun; Zhang, Shuai; Ahammed, Golam Jalal; Zhang, Guanqun; Jiang, Yuping; Zhou, Jie; Xia, Xiaojian; Zhou, Yanhong; Yu, Jingquan; Shi, Kai

    2015-01-01

    Increasing atmospheric CO2 concentrations ([CO2]) in agricultural and natural ecosystems is known to reduce plant stomatal opening, but it is unclear whether these CO2-induced stomatal alterations are associated with foliar pathogen infections. In this study, tomato plants were grown under ambient and elevated [CO2] and inoculated with Pseudomonas syringae pv. tomato strain DC3000, a strain that is virulent on tomato plants. We found that elevated [CO2] enhanced tomato defence against P. syringae. Scanning electron microscopy analysis revealed that stomatal aperture of elevated [CO2] plants was considerably smaller than their ambient counterparts, which affected the behaviour of P. syringae bacteria on the upper surface of epidermal peels. Pharmacological experiments revealed that nitric oxide (NO) played a role in elevated [CO2]-induced stomatal closure. Silencing key genes involved in NO generation and stomatal closing, nitrate reductase (NR) and guard cell slow-type anion channel 1 (SLAC1), blocked elevated [CO2]-induced stomatal closure and resulted in significant increases in P. syringae infection. However, the SLAC1-silenced plants, but not the NR-silenced plants, still had significantly higher defence under elevated [CO2] compared with plants treated with ambient [CO2]. Similar results were obtained when the stomata-limiting factor for P. syringae entry was excluded by syringe infiltration inoculation. These results indicate that elevated [CO2] induces defence against P. syringae in tomato plants, not only by reducing the stomata-mediated entry of P. syringae but also by invoking a stomata-independent pathway to counteract P. syringae. This information is valuable for designing proper strategies against bacterial pathogens under changing agricultural and natural ecosystems. PMID:25336683

  11. Tomato-Pseudomonas syringae interactions under elevated CO₂ concentration: the role of stomata.

    PubMed

    Li, Xin; Sun, Zenghui; Shao, Shujun; Zhang, Shuai; Ahammed, Golam Jalal; Zhang, Guanqun; Jiang, Yuping; Zhou, Jie; Xia, Xiaojian; Zhou, Yanhong; Yu, Jingquan; Shi, Kai

    2015-01-01

    Increasing atmospheric CO₂ concentrations ([CO₂]) in agricultural and natural ecosystems is known to reduce plant stomatal opening, but it is unclear whether these CO₂-induced stomatal alterations are associated with foliar pathogen infections. In this study, tomato plants were grown under ambient and elevated [CO₂] and inoculated with Pseudomonas syringae pv. tomato strain DC3000, a strain that is virulent on tomato plants. We found that elevated [CO₂] enhanced tomato defence against P. syringae. Scanning electron microscopy analysis revealed that stomatal aperture of elevated [CO₂] plants was considerably smaller than their ambient counterparts, which affected the behaviour of P. syringae bacteria on the upper surface of epidermal peels. Pharmacological experiments revealed that nitric oxide (NO) played a role in elevated [CO₂]-induced stomatal closure. Silencing key genes involved in NO generation and stomatal closing, nitrate reductase (NR) and guard cell slow-type anion channel 1 (SLAC1), blocked elevated [CO₂]-induced stomatal closure and resulted in significant increases in P. syringae infection. However, the SLAC1-silenced plants, but not the NR-silenced plants, still had significantly higher defence under elevated [CO₂] compared with plants treated with ambient [CO₂]. Similar results were obtained when the stomata-limiting factor for P. syringae entry was excluded by syringe infiltration inoculation. These results indicate that elevated [CO₂] induces defence against P. syringae in tomato plants, not only by reducing the stomata-mediated entry of P. syringae but also by invoking a stomata-independent pathway to counteract P. syringae. This information is valuable for designing proper strategies against bacterial pathogens under changing agricultural and natural ecosystems. PMID:25336683

  12. Growth and physiological responses of creeping bentgrass (Agrostis stolonifera) to elevated carbon dioxide concentrations.

    PubMed

    Burgess, Patrick; Huang, Bingru

    2014-01-01

    The atmospheric carbon dioxide level has increased and is predicted to continue increasing, which may affect various aspects of plant growth. The objective of this study was to investigate the effects of doubling the carbon dioxide level on the growth and physiological activities of a widely utilized cool-season turfgrass species, creeping bentgrass (Agrostis stolonifera L. 'Penncross'). 'Penncross' plants were established in fritted clay medium and maintained under well-irrigated and well-fertilized conditions in growth chambers. The plants were exposed to either ambient carbon dioxide concentrations (400±10 µmol L(-1)) or elevated carbon dioxide concentrations (800±10 µmol L(-1)) for 12 weeks. Plants grown under elevated carbon dioxide displayed a significantly faster growth rate of their lateral stems (stolons) and increased shoot and root dry weight but a reduced specific leaf area compared to those plants at ambient carbon dioxide levels. Fast stolon growth is a highly desirable trait for turfgrass establishment and recovery from physical damage. The root length and surface area were also increased due to the elevated CO2, which may facilitate water uptake and serve critical drought-avoidance roles when irrigation water is limited. Elevated carbon dioxide caused an increase in the leaf net photosynthetic rate but a reduction in the stomatal conductance and transpiration rate, contributing to improved water use efficiency in creeping bentgrass. Efficient water use is especially important for turfgrass plant survival when irrigation water is limited. Our results suggested that cool-season turfgrass species may greatly benefit from increasingly elevated carbon dioxide concentrations via growth promotion and increasing water use efficiency. PMID:26504537

  13. Growth and physiological responses of creeping bentgrass (Agrostis stolonifera) to elevated carbon dioxide concentrations

    PubMed Central

    Burgess, Patrick; Huang, Bingru

    2014-01-01

    The atmospheric carbon dioxide level has increased and is predicted to continue increasing, which may affect various aspects of plant growth. The objective of this study was to investigate the effects of doubling the carbon dioxide level on the growth and physiological activities of a widely utilized cool-season turfgrass species, creeping bentgrass (Agrostis stolonifera L. ‘Penncross’). ‘Penncross’ plants were established in fritted clay medium and maintained under well-irrigated and well-fertilized conditions in growth chambers. The plants were exposed to either ambient carbon dioxide concentrations (400±10 µmol L−1) or elevated carbon dioxide concentrations (800±10 µmol L−1) for 12 weeks. Plants grown under elevated carbon dioxide displayed a significantly faster growth rate of their lateral stems (stolons) and increased shoot and root dry weight but a reduced specific leaf area compared to those plants at ambient carbon dioxide levels. Fast stolon growth is a highly desirable trait for turfgrass establishment and recovery from physical damage. The root length and surface area were also increased due to the elevated CO2, which may facilitate water uptake and serve critical drought-avoidance roles when irrigation water is limited. Elevated carbon dioxide caused an increase in the leaf net photosynthetic rate but a reduction in the stomatal conductance and transpiration rate, contributing to improved water use efficiency in creeping bentgrass. Efficient water use is especially important for turfgrass plant survival when irrigation water is limited. Our results suggested that cool-season turfgrass species may greatly benefit from increasingly elevated carbon dioxide concentrations via growth promotion and increasing water use efficiency. PMID:26504537

  14. Effects of Elevated CO2 Concentration on Photosynthesis and Respiration of Populus Deltodies

    NASA Technical Reports Server (NTRS)

    Anderson, Angela M.

    1998-01-01

    To determine how increased atmospheric CO2 will affect the physiology of cottonwood trees, cuttings of the cloned Populus deltodies [cottonwood] were grown in open-top chambers containing ambient or elevated CO2 concentration. The control treatment was maintained at ambient Biosphere 2 atmospheric CO2 (c. 450 +/- 50 micro l/l), and elevated CO2 treatment was maintained at approximately double ambient Biosphere 2 atmospheric CO2 (c. 1000 +/- 50 micro l/l). The effects of elevated CO2 on leaf photosynthesis, and stomatal conductance were measured. The cottonwoods exposed to CO2 enrichment showed no significant indication of photosynthetic down-regulation. There was no significant difference in the maximum assimilation rate between the treatment and the control (P less than 0.24). The CO2 enriched treatment showed a decreased stomatal conductance of 15% (P less than 0.03). The elevated CO2 concentrated atmosphere had an effect on the respiration rates of the plants; the compensation point of the treatment was on average 13% higher than the control (P less than 0.01).

  15. Effect of elevated serum prolactin concentrations on cytokine production and natural killer cell activity.

    PubMed

    Clodi, M; Svoboda, T; Kotzmann, H; Deyssig, R; Woloszczuk, W; Zielinski, C C; Luger, A

    1992-12-01

    In vitro and in vivo studies in rodents and human suggested an immunostimulatory effect of prolactin. The aim of the present study was to determine the impact of chronically elevated serum prolactin concentrations on the immune system in patients with prolactinomas. For this purpose parameters of the humoral and cellular immune system were studied in seven patients with prolactinomas on two occasions (1) when their serum prolactin concentration had been normalized through treatment with dopamine agonists and (2) when their serum prolactin concentration was high. Serum concentrations of immunoglobulines, interleukin 1, 3 and 6, TNF-alpha, interferon-gamma and the soluble interleukin 2 receptor, leukocyte subsets and the natural killer cell activity were found to be within the normal range on both occasions, i.e. at normal and at high serum prolactin concentrations. The assumption could be made that long-lasting elevation of serum prolactin concentration induces adaptive changes when the acute stimulatory effects of prolactin on several parameters of the immune system have subsided. PMID:1369584

  16. Carbon material distribution and flux analysis under varying glucose concentrations in hydrogen-producing Clostridium tyrobutyricum JM1.

    PubMed

    Jo, Ji Hye; Kim, Woong

    2016-06-20

    Anaerobic glucose metabolism in hydrogen-producing Clostridium tyrobutyricum was investigated in batch culture with varying initial glucose concentrations (27.8-333.6mM). To understand the regulation of metabolism, the carbon material and reduction balances were applied to estimate the carbon flux distribution for the first time, and metabolic flux analysis (MFA) was used to provide qualitative information and guidance for effective metabolic design. The overall flux distribution suggested that C. tyrobutyricum metabolism has a high capacity for the production of butyrate and hydrogen at an initial glucose concentration of 222.4mM, with balanced activities of NADH and ATP. PMID:27140868

  17. PDX1 and ISL1 differentially coordinate with epigenetic modifications to regulate insulin gene expression in varied glucose concentrations.

    PubMed

    Wang, Weiping; Shi, Qiong; Guo, Ting; Yang, Zhe; Jia, Zhuqing; Chen, Ping; Zhou, Chunyan

    2016-06-15

    The mechanism of insulin gene transcription control in response to glucose concentration is poorly defined. The islet-restricted transcription factors PDX1 and ISL1 interact with BETA2, activating insulin gene expression. However, their contribution and hierarchical organization in insulin expression control based on glucose concentration remain unknown. We investigated PDX1 and ISL1 regulation of insulin gene expression in pancreatic β cells cultured in normal (5 mM/L) and high (25 mM/L) glucose conditions. ISL1 interacted with BETA2 to maintain basic insulin gene transcriptional activity under normal glucose. The ISL1-recruited cofactors SET9 and JMJD3 facilitated insulin gene histone modifications under normal glucose. In high-glucose concentrations, PDX1 formed a complex with BETA2 to enhance insulin gene expression. PDX1 also recruited SET9 and JMJD3 to promote the activation of histone modulation on the insulin promoter. This is the first evidence transcription factors orchestrate epigenetic modifications to control insulin gene expression based on glucose concentration. PMID:26994512

  18. Elevated White Blood Cell Count Is Associated with Higher Risk of Glucose Metabolism Disorders in Middle-Aged and Elderly Chinese People

    PubMed Central

    Jiang, Hua; Yan, Wen-Hua; Li, Chan-Juan; Wang, An-Ping; Dou, Jing-Tao; Mu, Yi-Ming

    2014-01-01

    White blood cell (WBC) count has been associated with diabetic risk, but whether the correlation is independent of other risk factors has hardly been studied. Moreover, very few such studies with large sample sizes have been conducted in Chinese. Therefore, we investigated the relationship between WBC count and glucose metabolism in china. We also examined the relevant variables of WBC count. A total of 9,697 subjects (mean age, 58.0 ± 9.1 years) were recruited. The subjects were classified into four groups, including subjects with normal glucose tolerance, isolated impaired fasting glucose, impaired glucose tolerance and type 2 diabetes mellitus (T2DM). We found that WBC count increased as glucose metabolism disorders exacerbated. WBC count was also positively correlated with waist hip ratio, body mass index, smoking, triglycerides, glycosylated haemoglobin A1c (HbA1c) and 2-h postprandial glucose. In addition, high density lipoprotein and the female gender were inversely correlated with WBC levels. In patients with previously diagnosed T2DM, the course of T2DM was not correlated with WBC count. Our findings indicate that elevated WBC count is independently associated with worsening of glucose metabolism in middle-aged and elderly Chinese. In addition, loss of weight, smoking cessation, lipid-modifying therapies, and control of postprandial plasma glucose and HbA1c may ameliorate the chronic low-grade inflammation. PMID:24852600

  19. Distribution of Elevated Nitrate Concentrations in Ground Water in Washington State

    USGS Publications Warehouse

    Frans, Lonna

    2008-01-01

    More than 60 percent of the population of Washington State uses ground water for their drinking and cooking needs. Nitrate concentrations in ground water are elevated in parts of the State as a result of various land-use practices, including fertilizer application, dairy operations and ranching, and septic-system use. Shallow wells generally are more vulnerable to nitrate contamination than deeper wells (Williamson and others, 1998; Ebbert and others, 2000). In order to protect public health, the Washington State Department of Health requires that public water systems regularly measure nitrate in their wells. Public water systems serving more than 25 people collect water samples at least annually; systems serving from 2 to 14 people collect water samples at least every 3 years. Private well owners serving one residence may be required to sample when the well is first drilled, but are unregulated after that. As a result, limited information is available to citizens and public health officials about potential exposure to elevated nitrate concentrations for people whose primary drinking-water sources are private wells. The U.S. Geological Survey and Washington State Department of Health collaborated to examine water-quality data from public water systems and develop models that calculate the probability of detecting elevated nitrate concentrations in ground water. Maps were then developed to estimate ground water vulnerability to nitrate in areas where limited data are available.

  20. Increased soil salinity causes elevated cadmium concentrations in field-grown potato tubers

    SciTech Connect

    McLaughlin, M.J.; Tiller, K.G.; Beech, T.A.

    1994-09-01

    Elevated Cd concentrations have been observed in potato (Solanum tuberosum L.) tubers from commercial crops in certain regions of southern Australia. Reasons for enhanced Cd uptake by tubers were investigated by a survey of commercial crops and associated soils. Eighty-nine sites were selected and paired tuber and soil samples taken. Concentration of Cd in tubers was compared to potato variety, tuber elemental composition, and chemical-physical characteristics of topsoil (0-150) and subsoil (150-300 mm). Tuber Cd concentrations were positively related to soil electrical conductivity (EC) and extractable Cl (R{sup 2} = 0.62, P < 0.001) in the topsoil, with extractable Cl accounting for more variation than EC. Tuber Cd concentrations were not strongly related (R{sup 2} = 0.23, P < 0.05) to potato variety alone. However, inclusion of variety and EDTA-extractable Zn with water-extractable Cl in a multivariate model resulted in a small but significant improvement in the variance accounted for by the model (R{sup 2} = 0.73, p < 0.001). Tuber Cd was unrelated to tuber concentrations of P or tuber but was positively related to concentrations of major cations in the tuber particularly Na. Soil pH, total C, EDTA-extractable Cd, or particle-size distribution were not correlated to tuber Cd concentrations, either singly or after inclusion in a multivariate model with soil Cl concentrations. As Cl is known to mobilize soil Cd and increase its phytoavailability, elevated Cd concentrations in potato tubers in southern Australia appear to be largely a result of the use of saline irrigation waters. 41 refs., 5 figs., 4 tabs.

  1. Glucose tolerance, blood lipid, insulin and glucagon concentration after single or continuous administration of aspartame in diabetics.

    PubMed

    Okuno, G; Kawakami, F; Tako, H; Kashihara, T; Shibamoto, S; Yamazaki, T; Yamamoto, K; Saeki, M

    1986-04-01

    A nutritive sweetener, aspartame (L-aspartyl-L-phenylalanine methylester) was administered orally to normal controls and diabetic patients in order to evaluate effects on blood glucose, lipids and pancreatic hormone secretion. An oral glucose tolerance test was also performed in the same subjects as a control study of aspartame administration. In 7 normal controls and 22 untreated diabetics, a single dose of 500 mg aspartame, equivalent to 100 g glucose in sweetness, induced no increase in blood glucose concentration. Rather, a small but significant decrease in blood glucose was noticed 2 or 3 h after administration. The decrease in blood glucose was found to be smallest in the control and became greater as the diabetes increased in severity. No significant change in blood insulin or glucagon concentration during a 3-h period was observed in either the controls or the diabetics. The second study was designed to determine the effects of 2 weeks' continuous administration of 125 mg aspartame, equal in sweetness to the mean daily consumption of sugar (20-30 g) in Japan, to 9 hospitalized diabetics with steady-state glycemic control. The glucose tolerance showed no significant change after 2 weeks' administration. Fasting, 1 h and 2 h postprandial blood glucose, blood cholesterol, triglyceride and HDL-cholesterol were also unaffected. From these and other published results, aspartame would seem to be a useful alternative nutrient sweetener for patients with diabetes mellitus. PMID:3522147

  2. Glucose transport and milk secretion during manipulated plasma insulin and glucose concentrations and during LPS-induced mastitis in dairy cows.

    PubMed

    Gross, J J; van Dorland, H A; Wellnitz, O; Bruckmaier, R M

    2015-08-01

    In dairy cows, glucose is essential as energy source and substrate for milk constituents. The objective of this study was to investigate effects of long-term manipulated glucose and insulin concentrations in combination with a LPS-induced mastitis on mRNA abundance of glucose transporters and factors involved in milk composition. Focusing on direct effects of insulin and glucose without influence of periparturient endocrine adaptations, 18 dairy cows (28 ± 6 weeks of lactation) were randomly assigned to one of three infusion treatments for 56 h (six animals each). Treatments included a hyperinsulinemic hypoglycaemic clamp (HypoG), a hyperinsulinemic euglycaemic clamp (EuG) and a control group (NaCl). After 48 h of infusions, an intramammary challenge with LPS from E. coli was performed and infusions continued for additional 8 h. Mammary gland biopsies were taken before, at 48 (before LPS challenge) and at 56 h (after LPS challenge) of infusion, and mRNA abundance of genes involved in mammary gland metabolism was measured by RT-qPCR. During the 48 h of infusions, mRNA abundance of glucose transporters GLUT1, 3, 4, 8, 12, SGLT1, 2) was not affected in HypoG, while they were downregulated in EuG. The mRNA abundance of alpha-lactalbumin, insulin-induced gene 1, κ-casein and acetyl-CoA carboxylase was downregulated in HypoG, but not affected in EuG. Contrary during the intramammary LPS challenge, most of the glucose transporters were downregulated in NaCl and HypoG, but not in EuG. The mRNA abundance of glucose transporters in the mammary gland seems not to be affected by a shortage of glucose, while enzymes and milk constituents directly depending on glucose as a substrate are immediately downregulated. During LPS-induced mastitis in combination with hypoglycaemia, mammary gland metabolism was more aligned to save glucose for the immune system compared to a situation without limited glucose availability during EuG. PMID:25319117

  3. Responses of Legume Versus Nonlegume Tropical Tree Seedlings to Elevated CO2 Concentration1[OA

    PubMed Central

    Cernusak, Lucas A.; Winter, Klaus; Martínez, Carlos; Correa, Edwin; Aranda, Jorge; Garcia, Milton; Jaramillo, Carlos; Turner, Benjamin L.

    2011-01-01

    We investigated responses of growth, leaf gas exchange, carbon-isotope discrimination, and whole-plant water-use efficiency (WP) to elevated CO2 concentration ([CO2]) in seedlings of five leguminous and five nonleguminous tropical tree species. Plants were grown at CO2 partial pressures of 40 and 70 Pa. As a group, legumes did not differ from nonlegumes in growth response to elevated [CO2]. The mean ratio of final plant dry mass at elevated to ambient [CO2] (ME/MA) was 1.32 and 1.24 for legumes and nonlegumes, respectively. However, there was large variation in ME/MA among legume species (0.92–2.35), whereas nonlegumes varied much less (1.21–1.29). Variation among legume species in ME/MA was closely correlated with their capacity for nodule formation, as expressed by nodule mass ratio, the dry mass of nodules for a given plant dry mass. WP increased markedly in response to elevated [CO2] in all species. The ratio of intercellular to ambient CO2 partial pressures during photosynthesis remained approximately constant at ambient and elevated [CO2], as did carbon isotope discrimination, suggesting that WP should increase proportionally for a given increase in atmospheric [CO2]. These results suggest that tree legumes with a strong capacity for nodule formation could have a competitive advantage in tropical forests as atmospheric [CO2] rises and that the water-use efficiency of tropical tree species will increase under elevated [CO2]. PMID:21788363

  4. Elevation of brain glucose and polyol-pathway intermediates with accompanying brain-copper deficiency in patients with Alzheimer's disease: metabolic basis for dementia.

    PubMed

    Xu, Jingshu; Begley, Paul; Church, Stephanie J; Patassini, Stefano; McHarg, Selina; Kureishy, Nina; Hollywood, Katherine A; Waldvogel, Henry J; Liu, Hong; Zhang, Shaoping; Lin, Wanchang; Herholz, Karl; Turner, Clinton; Synek, Beth J; Curtis, Maurice A; Rivers-Auty, Jack; Lawrence, Catherine B; Kellett, Katherine A B; Hooper, Nigel M; Vardy, Emma R L C; Wu, Donghai; Unwin, Richard D; Faull, Richard L M; Dowsey, Andrew W; Cooper, Garth J S

    2016-01-01

    Impairment of brain-glucose uptake and brain-copper regulation occurs in Alzheimer's disease (AD). Here we sought to further elucidate the processes that cause neurodegeneration in AD by measuring levels of metabolites and metals in brain regions that undergo different degrees of damage. We employed mass spectrometry (MS) to measure metabolites and metals in seven post-mortem brain regions of nine AD patients and nine controls, and plasma-glucose and plasma-copper levels in an ante-mortem case-control study. Glucose, sorbitol and fructose were markedly elevated in all AD brain regions, whereas copper was correspondingly deficient throughout (all P < 0.0001). In the ante-mortem case-control study, by contrast, plasma-glucose and plasma-copper levels did not differ between patients and controls. There were pervasive defects in regulation of glucose and copper in AD brain but no evidence for corresponding systemic abnormalities in plasma. Elevation of brain glucose and deficient brain copper potentially contribute to the pathogenesis of neurodegeneration in AD. PMID:27276998

  5. Elevation of brain glucose and polyol-pathway intermediates with accompanying brain-copper deficiency in patients with Alzheimer’s disease: metabolic basis for dementia

    PubMed Central

    Xu, Jingshu; Begley, Paul; Church, Stephanie J.; Patassini, Stefano; McHarg, Selina; Kureishy, Nina; Hollywood, Katherine A.; Waldvogel, Henry J.; Liu, Hong; Zhang, Shaoping; Lin, Wanchang; Herholz, Karl; Turner, Clinton; Synek, Beth J.; Curtis, Maurice A.; Rivers-Auty, Jack; Lawrence, Catherine B.; Kellett, Katherine A. B.; Hooper, Nigel M.; Vardy, Emma R. L. C.; Wu, Donghai; Unwin, Richard D.; Faull, Richard L. M.; Dowsey, Andrew W.; Cooper, Garth J. S.

    2016-01-01

    Impairment of brain-glucose uptake and brain-copper regulation occurs in Alzheimer’s disease (AD). Here we sought to further elucidate the processes that cause neurodegeneration in AD by measuring levels of metabolites and metals in brain regions that undergo different degrees of damage. We employed mass spectrometry (MS) to measure metabolites and metals in seven post-mortem brain regions of nine AD patients and nine controls, and plasma-glucose and plasma-copper levels in an ante-mortem case-control study. Glucose, sorbitol and fructose were markedly elevated in all AD brain regions, whereas copper was correspondingly deficient throughout (all P < 0.0001). In the ante-mortem case-control study, by contrast, plasma-glucose and plasma-copper levels did not differ between patients and controls. There were pervasive defects in regulation of glucose and copper in AD brain but no evidence for corresponding systemic abnormalities in plasma. Elevation of brain glucose and deficient brain copper potentially contribute to the pathogenesis of neurodegeneration in AD. PMID:27276998

  6. [Clinical research on improvement of glucose metabolic marker level by coffee drinking-validity of saliva caffeine concentration measurement].

    PubMed

    Okada, Tomoko; Kobayashi, Daisuke; Kono, Suminori; Shimazoe, Takao

    2010-05-01

    We measured both serum and saliva caffeine concentration using HPLC and assessed the correlation between them in volunteers with mild obesity. Significant correlation was shown between saliva and serum caffeine concentration. It may be necessary to measure caffeine metabolite concentration because its metabolites may also have an improving effect of glucose metabolism. In summary, we found that saliva caffeine concentration measurement was useful to assess caffeine intake level. Moreover, it will be helpful to know whether caffeine has an improving effect of glucose metabolism. PMID:20460869

  7. Elevated Atmospheric Carbon Dioxide Concentrations Amplify Alternaria alternata Sporulation and Total Antigen Production

    PubMed Central

    Wolf, Julie; O’Neill, Nichole R.; Rogers, Christine A.; Muilenberg, Michael L.; Ziska, Lewis H.

    2010-01-01

    Background Although the effect of elevated carbon dioxide (CO2) concentration on pollen production has been established in some plant species, impacts on fungal sporulation and antigen production have not been elucidated. Objective Our purpose was to examine the effects of rising atmospheric CO2 concentrations on the quantity and quality of fungal spores produced on timothy (Phleum pratense) leaves. Methods Timothy plants were grown at four CO2 concentrations (300, 400, 500, and 600 μmol/mol). Leaves were used as growth substrate for Alternaria alternata and Cladosporium phlei. The spore abundance produced by both fungi, as well as the size (microscopy) and antigenic protein content (ELISA) of A. alternata, were quantified. Results Leaf carbon-to-nitrogen ratio was greater at 500 and 600 μmol/mol, and leaf biomass was greater at 600 μmol/mol than at the lower CO2 concentrations. Leaf carbon-to-nitrogen ratio was positively correlated with A. alternata spore production per gram of leaf but negatively correlated with antigenic protein content per spore. At 500 and 600 μmol/mol CO2 concentrations, A. alternata produced nearly three times the number of spores and more than twice the total antigenic protein per plant than at lower concentrations. C. phlei spore production was positively correlated with leaf carbon-to-nitrogen ratio, but overall spore production was much lower than in A. alternata, and total per-plant production did not vary among CO2 concentrations. Conclusions Elevated CO2 concentrations often increase plant leaf biomass and carbon-to-nitrogen ratio. Here we demonstrate for the first time that these leaf changes are associated with increased spore production by A. alternata, a ubiquitous allergenic fungus. This response may contribute to the increasing prevalence of allergies and asthma. PMID:20462828

  8. [Effects of drought stress, high temperature and elevated CO2 concentration on the growth of winter wheat].

    PubMed

    Si, Fu-Yan; Qiao, Yun-Zhou; Jiang, Jing-Wei; Dong, Bao-Di; Shi, Chang-Hai; Liu, Meng-Yu

    2014-09-01

    The impacts of climate change on the grain yield, photosynthesis, and water conditions of winter wheat were assessed based on an experiment, in which wheat plants were subjected to ambient and elevated CO2 concentrations, ambient and elevated temperatures, and low and high water conditions independently and in combination. The CO2 enrichment alone had no effect on the photosynthesis of winter wheat, whereas higher temperature and drought significantly decreased the photosynthetic rate. Water conditions in flag leaves were not significantly changed at the elevated CO2 concentration or elevated temperature. However, drought stress decreased the relative water content in flag leaves, and the combination of elevated temperature and drought reduced the water potential in flag leaves. The combination of elevated CO2 concentration, elevated temperature, and drought significantly reduced the photosynthetic rate and water conditions, and led to a 41.4% decrease in grain yield. The elevated CO2 concentration alone increased the grain yield by 21.2%, whereas the elevated temperature decreased the grain yield by 12.3%. The grain yield was not affected by the combination of elevated CO2 concentration and temperature, but the grain yield was significantly decreased by the drought stress if combined with any of the climate scenarios applied in this study. These findings suggested that maintaining high soil water content might be a vital means of reducing the potential harm caused by the climate change. PMID:25757312

  9. Phytochemical changes in leaves of subtropical grasses and fynbos shrubs at elevated atmospheric CO 2 concentrations

    NASA Astrophysics Data System (ADS)

    Hattas, D.; Stock, W. D.; Mabusela, W. T.; Green, I. R.

    2005-07-01

    The effects of elevated atmospheric CO 2 concentrations on plant polyphenolic, tannin, nitrogen, phosphorus and total nonstructural carbohydrate concentrations were investigated in leaves of subtropical grass and fynbos shrub species. The hypothesis tested was that carbon-based secondary compounds would increase when carbon gain is in excess of growth requirements. This premise was tested in two ecosystems involving plants with different photosynthetic mechanisms and growth strategies. The first ecosystem comprised grasses from a C 4-dominated, subtropical grassland, where three plots were subjected to three different free air CO 2 enrichment treatments, i.e., elevated (600 to 800 μmol mol -1), intermediate (400 μmol mol -1) and ambient atmospheric CO 2. One of the seven grass species, Alloteropsis semialata, had a C 3 photosynthetic pathway while the other grasses were all C 4. The second ecosystem was simulated in a microcosm experiment where three fynbos species were grown in open-top chambers at ambient and 700 μmol mol -1 atmospheric CO 2 in low nutrient acid sands typical of south western coastal and mountain fynbos ecosystems. Results showed that polyphenolics and tannins did not increase in the grass species under elevated CO 2 and only in Leucadendron laureolum among the fynbos species. Similarly, foliar nitrogen content of grasses was largely unaffected by elevated CO 2, and among the fynbos species, only L. laureolum and Leucadendron xanthoconus showed changes in foliar nitrogen content under elevated CO 2, but these were of different magnitude. The overall decrease in nitrogen and phosphorus and consequent increase in C:N and C:P ratio in both ecosystems, along with the increase in polyphenolics and tannins in L. laureolum in the fynbos ecosystem, may negatively affect forage quality and decomposition rates. It is concluded that fast growing grasses do not experience sink limitation and invest extra carbon into growth rather than polyphenolics and

  10. Elevated soil lead concentrations in residential yards in Appleton, WI, a small Midwestern city

    NASA Astrophysics Data System (ADS)

    Clark, J. J.; Knudsen, A. C.

    2010-12-01

    Elevated soil lead concentrations are well documented in large urban areas, having been attributed to a combination of leaded-paint, leaded-gasoline, and industrial emissions. Fewer studies, however, have been conducted in smaller communities. We analyzed 200 surface soils in the neighborhood near Lawrence University’s campus in Appleton, WI (population ~70,000). Like many larger cities Appleton has a historic city-center. However, it is has no high-density housing or commercial districts and has not seen heavy traffic. The socioeconomic pressures that lead to disrepair of inner city neighborhoods have been less prevalent here as well. At each property 3 integrated samples were taken, one adjacent to the front of the house, one in the front lawn, and one between the road and sidewalk. We correlated building and property traits (e.g. structure age, distance from road, exterior type, exterior condition, direction of exposure, and assessed home value) with soil lead concentrations determined by XRF and subsequently, mapped these data for geospatial patterns. Soil lead concentrations in the city park and campus greens were typically less than 100 ppm. The highest lead concentrations are close to campus, which has a number of civil war era buildings and homes. High lead concentrations (averaging over 1,000 ppm near the home, with concentrations as high as 10,000 ppm) were associated with aging, poorly maintained structures as expected. However, a number of well-maintained structures also show substantially elevated concentrations. These soil lead concentrations are not dissimilar to those found in much larger cities such as New Orleans, Milwaukee, and Chicago. Lead levels dropped quickly as distance from the house increased suggesting that the contamination is from lead paint and not from gasoline exhaust. Furthermore, samples taken adjacent to the main arterial through town exhibited relatively low, but slightly elevated lead levels (~250 ppm). Not surprisingly

  11. Factors associated with elevated blood lead concentrations in children in Karachi, Pakistan.

    PubMed Central

    Rahbar, Mohammad Hossein; White, Franklin; Agboatwalla, Mubina; Hozhabri, Siroos; Luby, Stephen

    2002-01-01

    OBJECTIVES: To confirm whether blood lead concentrations in Karachi were as high as reported in 1989 and to identify which types of exposure to lead contribute most to elevated blood lead concentrations in children in Karachi. METHODS: A total of 430 children aged 36-60 months were selected through a geographically stratified design from the city centre, two suburbs, a rural community and an island situated within the harbour at Karachi. Blood samples were collected from children and a pretested questionnaire was administered to assess the effect of various types of exposure. Cooked food, drinking-water and house dust samples were collected from households. FINDINGS: About 80% of children had blood lead concentrations 10 g/dl, with an overall mean of 15.6 g/dl. At the 5% level of significance, houses nearer to the main intersection in the city centre, application of surma to children's eyes, father's exposure to lead at workplace, parents' illiteracy and child's habit of hand- to-mouth activity were among variables associated with elevated lead concentrations in blood. CONCLUSION: These findings are of public health concern, as most children in Karachi are likely to suffer some degree of intellectual impairment as a result of environmental lead exposure. We believe that there is enough evidence of the continuing problem of lead in petrol to prompt the petroleum industry to take action. The evidence also shows the need for appropriate interventions in reducing the burden due to other factors associated with this toxic element. PMID:12471396

  12. Identification of potential source areas for elevated PM2.5, nitrate and sulfate concentrations

    NASA Astrophysics Data System (ADS)

    Heo, Jongbae; McGinnis, Jerome E.; de Foy, Benjamin; Schauer, James J.

    2013-06-01

    Extreme events or episodes of ambient fine particulate matter (PM2.5), in which daily mass concentrations are substantially higher than annual averages, have been frequently observed in southern Wisconsin, US. Determining the cause of events has been a great challenge to local governments responsible for protecting public health and complying with the 24-h PM2.5 standard. This study analyzed air parcel movements originating from emission source areas, and trends in PM2.5 concentrations in order to determine the important factors involved in elevated PM2.5 episodes in the region. A single backward trajectory analysis coupled with PM2.5 concentrations observed at Federal Reference Method Network (FRM) sites in Madison, Milwaukee and Waukesha; and nitrate and sulfate concentrations monitored at a Chemical Speciation Network (CSN) site in Milwaukee, Wisconsin, from 2002 to 2010 were examined. The PM2.5 concentrations from the FRM showed the total PM2.5 mass during the episodes were higher in Madison than in Milwaukee and Waukesha, while annual average concentrations were lower in Madison. However, the temporal trend in frequency of elevated PM2.5 episodes was remarkably similar across sites during the entire study period and high frequency episodes occurring from 2005 to 2007. Residence time analysis of backward trajectories calculated for all recorded data indicated episode changes were mainly driven by year-to-year variations of air mass movements originating in high emissions areas. Potential Source Contribution Function (PSCF) results showed the extreme events of PM2.5 occurred during times when trajectories passed over ammonia emissions hotspots as well as large stationary emissions. Enhanced nitrate and sulfate concentrations which were the major episode components were strongly influenced by air masses trajectories originating from the Ohio River Valley and adjacent states.

  13. Adaptation of Escherichia coli to elevated sodium concentrations increases cation tolerance and enables greater lactic acid production.

    PubMed

    Wu, Xianghao; Altman, Ronni; Eiteman, Mark A; Altman, Elliot

    2014-05-01

    Adaptive evolution was employed to generate sodium (Na(+))-tolerant mutants of Escherichia coli MG1655. Four mutants with elevated sodium tolerance, designated ALS1184, ALS1185, ALS1186, and ALS1187, were independently isolated after 73 days of serial transfer in medium containing progressively greater Na(+) concentrations. The isolates also showed increased tolerance of K(+), although this cation was not used for selective pressure. None of the adapted mutants showed increased tolerance to the nonionic osmolyte sucrose. Several physiological parameters of E. coli MG1655 and ALS1187, the isolate with the greatest Na(+) tolerance, were calculated and compared using glucose-limited chemostats. Genome sequencing showed that the ALS1187 isolate contained mutations in five genes, emrR, hfq, kil, rpsG, and sspA, all of which could potentially affect the ability of E. coli to tolerate Na(+). Two of these genes, hfq and sspA, are known to be involved in global regulatory processes that help cells endure a variety of cellular stresses. Pyruvate formate lyase knockouts were constructed in strains MG1655 and ALS1187 to determine whether increased Na(+) tolerance afforded increased anaerobic generation of lactate. In fed-batch fermentations, E. coli ALS1187 pflB generated 76.2 g/liter lactate compared to MG1655 pflB, which generated only 56.3 g/liter lactate. PMID:24584246

  14. Reducing dietary fat from a meal increases the bioavailability of exogenous carbohydrate without altering plasma glucose concentration.

    PubMed

    Knuth, Nicolas D; Shrivastava, Cara R; Horowitz, Jeffrey F

    2009-01-01

    The primary goal of this study was to determine the acute glycemic and endocrine responses to the reduction of fat content from a meal. On three separate occasions, nine overweight subjects (body mass index = 30 +/- 1 kg/m(2); 5 men, 4 women) consumed 1) a control meal ( approximately 800 kcal; 100 g of carbohydrate, 31 g of fat, and 30 g of protein), 2) a low-fat meal ( approximately 530 kcal; 100 g of carbohydrate, 1 g of fat, and 30 g of protein), or 3) a low-fat meal plus lipid infusion [same meal as low-fat meal, but the total energy provided was the same as control (800 kcal), with the "missing" fat ( approximately 30 g) provided via an intravenous lipid infusion]. All three meals contained [(13)C]glucose (3 mg/kg body wt) to assess the bioavailability of ingested glucose. During the 5-h period after each meal, we measured the recovery of [(13)C]glucose in plasma, plasma glucose, and insulin concentrations. We also measured plasma concentration of the gastrointestinal peptides: glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide-1 (GLP-1), and peptide YY(3-36) (PYY(3-36)). The recovery of the ingested [(13)C]glucose in the hour after ingestion was greater (P < 0.05) after the low-fat than after the control meal [area under the curve (AUC): 1,206 +/- 252 and 687 +/- 161 microM.h, respectively]. However, removing dietary fat from the meal did not affect the plasma concentration of glucose or insulin. Importantly, [(13)C]glucose recovery was not different during the low-fat and lipid infusion trials (AUC: 1,206 +/- 252 and 1,134 +/- 247 microM.h, respectively), indicating that the accelerated delivery of exogenous glucose found after removing fat from the meal is due exclusively to the reduction of fat in the gastrointestinal tract. In parallel with these findings, the reduction in fat calories from the meal reduced plasma concentration of GIP, GLP-1, and PYY(3-36). In summary, these data suggest that removing fat from the diet expedited

  15. Retrospective Study of Cryptococcal Meningitis With Elevated Minimum Inhibitory Concentration to Fluconazole in Immunocompromised Patients

    PubMed Central

    Nasri, Hashem; Kabbani, Sarah; Bou Alwan, Melhim; Wang, Yun F.; Rebolledo, Paulina A.; Kraft, Colleen S.; Nguyen, Minh L.; Anderson, Albert M.; Rouphael, Nadine

    2016-01-01

    Background. Mortality for cryptococcal meningitis remains significant, in spite of available treatment. Resistance to first-line maintenance therapy, particularly fluconazole, has been reported. Methods. A retrospective chart review was performed on immunocompromised patients with cryptococcal meningitis, who had susceptibility testing performed between January 2001 and December 2011, at 3 hospitals in Atlanta, Georgia. Results. A total of 35 immunocompromised patients with cryptococcal meningitis were identified, 13 (37.1%) of whom had an elevated minimum inhibitory concentration (MIC) to fluconazole (MIC ≥16 µg/mL). Eighty percent of patients were males with African American predominance, the median age was 37 years, and 80% of the patients were human immunodeficiency virus (HIV) positive. Subsequent recurrence of cryptococcal meningitis was more likely in HIV patients compared with solid organ transplant patients (P = .0366). Overall, there was a statistically significant increase in an elevated MIC to fluconazole in patients who had a history of prior azole use (odds ratio, 10.12; 95% confidence interval, 2.04–50.16). Patients with an elevated MIC to fluconazole and those with a high cerebrospinal fluid cryptococcal antigen load (≥1:512) were more likely to have central nervous system complications (P = .0358 and P = .023, respectively). Although no association was observed between an elevated MIC to fluconazole and mortality, those who received voriconazole or high-dose fluconazole (≥800 mg) for maintenance therapy were more likely to survive (P = .0288). Conclusions. Additional studies are required to further investigate the morbidity and mortality associated with an elevated MIC to fluconazole in cryptococcal meningitis, to determine when it is appropriate to perform susceptibility testing, and to evaluate its cost effectiveness. PMID:27419153

  16. Elevated CO2 significantly delays reproductive development of soybean under Free-Air Concentration Enrichment (FACE).

    PubMed

    Castro, Joseph C; Dohleman, Frank G; Bernacchi, Carl J; Long, Stephen P

    2009-01-01

    The effect of rising atmospheric concentration of carbon dioxide [CO(2)] on the reproductive development of soybean (Glycine max. Merr) has not been evaluated under open-air field conditions. Soybeans grown under Free-Air CO(2) Enrichment (FACE) exhibit warmer canopies due to decreased latent heat loss because of decreased stomatal conductance. According to development models based on accumulated thermal time, or growing degree days ( degrees Cd), increased canopy temperature should accelerate development. The SoyFACE research facility (Champaign, Illinois, USA) was used to test the hypothesis that development is accelerated in soybean when grown in [CO(2)] elevated to 548 micromol mol(-1). Canopy temperature was measured continuously with infrared thermometry, and used in turn to calculate GDD. Opposite to expectation, elevated [CO(2)], while increasing canopy temperature, delayed reproductive development by up to 3 days (P <0.05). Soybean grown in elevated [CO(2)] required approximately 49 degrees Cd more GDD (P <0.05) to complete full bloom stage (R2) and approximately 52 degrees Cd more GDD (P <0.05) to complete the beginning seed (R5) stage, but needed approximately 46 degrees Cd fewer GDD (P <0.05) to complete seed filling (R6). Soybeans grown in elevated [CO(2)] produced significantly more nodes (P <0.01) on the main stem than those grown under current [CO(2)]. This may explain the delay in completion of reproductive development and final maturation of the crop under elevated [CO(2)]. These results show a direct effect of rising [CO(2)] on plant development that will affect both projections of grain supply and may be significant to other species including those in natural communities. PMID:19561049

  17. Microfluidic devices with disposable enzyme electrode for electrochemical monitoring of glucose concentrations.

    PubMed

    Li, Xin; Zhang, Fan; Shi, Jian; Wang, Li; Tian, Jing-Hua; Zhou, Xiong-Tu; Jiang, Lian-Mei; Liu, Li; Zhao, Zhen-Jie; He, Pin-Gang; Chen, Yong

    2011-11-01

    This article describes the fabrication of tube-like microchannels made of UV curable polymer on a glass substrate and the device assembling with a disposable enzyme-working electrode for high-sensitivity electrochemical detection. While both reference and counter electrodes are patterned on the surface of the glass substrate, the working electrode is flipped on the top of the channel with an open access, providing a face-to-face probing configuration. When the enzyme electrode is contaminated or degraded, it can be easily replaced by a new one, keeping the main body of the device and the detection schema unchanged. Using glucose oxidase-coated gold electrodes, we were able to determine a linear amperometry response to the glucose concentrations in the range of 2-16  mM. By replacing the as-prepared working electrode by the one after thermal treatments, we showed a much more degraded enzyme electrode activity, enabling efficient determination of the electrode quality as well as the whole process optimization. PMID:22038673

  18. Elevation of Glucose 6-Phosphate Dehydrogenase Activity Induced by Amplified Insulin Response in Low Glutathione Levels in Rat Liver.

    PubMed

    Taniguchi, Misako; Mori, Nobuko; Iramina, Chizuru; Yasutake, Akira

    2016-01-01

    Weanling male Wistar rats were fed on a 10% soybean protein isolate (SPI) diet for 3 weeks with or without supplementing 0.3% sulfur-containing amino acids (SAA; methionine or cystine) to examine relationship between glutathione (GSH) levels and activities of NADPH-producing enzymes, glucose 6-phosphate dehydrogenase (G6PD) and malic enzyme (ME), in the liver. Of rats on the 10% SPI diet, GSH levels were lower and the enzyme activities were higher than of those fed on an SAA-supplemented diet. Despite the lower GSH level, γ-glutamylcysteine synthetase (γ-GCS) activity was higher in the 10% SPI group than other groups. Examination of mRNAs of G6PD and ME suggested that the GSH-suppressing effect on enzyme induction occurred prior to and/or at transcriptional levels. Gel electrophoresis of G6PD indicated that low GSH status caused a decrease in reduced form and an increase in oxidized form of the enzyme, suggesting an accelerated turnover rate of the enzyme. In primary cultured hepatocytes, insulin response to induce G6PD activity was augmented in low GSH levels manipulated in the presence of buthionine sulfoximine. These findings indicated that elevation of the G6PD activity in low GSH levels was caused by amplified insulin response for expression of the enzyme and accelerated turnover rate of the enzyme molecule. PMID:27597985

  19. Elevation of Glucose 6-Phosphate Dehydrogenase Activity Induced by Amplified Insulin Response in Low Glutathione Levels in Rat Liver

    PubMed Central

    Taniguchi, Misako; Mori, Nobuko; Iramina, Chizuru

    2016-01-01

    Weanling male Wistar rats were fed on a 10% soybean protein isolate (SPI) diet for 3 weeks with or without supplementing 0.3% sulfur-containing amino acids (SAA; methionine or cystine) to examine relationship between glutathione (GSH) levels and activities of NADPH-producing enzymes, glucose 6-phosphate dehydrogenase (G6PD) and malic enzyme (ME), in the liver. Of rats on the 10% SPI diet, GSH levels were lower and the enzyme activities were higher than of those fed on an SAA-supplemented diet. Despite the lower GSH level, γ-glutamylcysteine synthetase (γ-GCS) activity was higher in the 10% SPI group than other groups. Examination of mRNAs of G6PD and ME suggested that the GSH-suppressing effect on enzyme induction occurred prior to and/or at transcriptional levels. Gel electrophoresis of G6PD indicated that low GSH status caused a decrease in reduced form and an increase in oxidized form of the enzyme, suggesting an accelerated turnover rate of the enzyme. In primary cultured hepatocytes, insulin response to induce G6PD activity was augmented in low GSH levels manipulated in the presence of buthionine sulfoximine. These findings indicated that elevation of the G6PD activity in low GSH levels was caused by amplified insulin response for expression of the enzyme and accelerated turnover rate of the enzyme molecule. PMID:27597985

  20. Elevation of intracellular Zn2+ level by nanomolar concentrations of triclocarban in rat thymocytes.

    PubMed

    Morita, Junpei; Teramachi, Aoi; Sanagawa, Yosuke; Toyson, Saramaiti; Yamamoto, Hiroshi; Oyama, Yasuo

    2012-12-17

    It was recently reported that nanomolar concentrations of triclocarban, an antimicrobial agent, were detected in human blood after the use of soap containing triclocarban. Due to the widespread use of triclocarban in adult and infant personal care products, the report prompted us to study its cytotoxicity. The cytotoxicity of triclocarban was examined in rat thymocytes by using a cytometric technique with propidium iodide for examining cell lethality, FluoZin-3-AM for monitoring the intracellular Zn(2+) level, and 5-chloromethylfluorescencein diacetate for estimating the cellular content of non-protein thiol. The incubation with triclocarban at nanomolar concentrations (50-500nM) for 1h did not affect cell lethality but significantly elevated the intracellular Zn(2+) level. The elevation of the intracellular Zn(2+) level by triclocarban was not significantly dependent on external Zn(2+) level. There was a negative correlation (r=-0.9225) between the effect on the intracellular Zn(2+) level and that on the cellular content of non-protein thiol. These results suggest that nanomolar concentrations of triclocarban decrease the cellular content of non-protein thiol, leading to intracellular Zn(2+) release. Since zinc plays physiological roles in mammalian cells, the percutaneous absorption of triclocarban from soap may, therefore, affect some cellular functions. PMID:23099084

  1. Bedside monitoring of subcutaneous interstitial glucose in type 1 diabetic subjects using microdialysis and infrared spectrometry with optimal correlation to blood glucose concentrations

    NASA Astrophysics Data System (ADS)

    Heise, H. Michael; Damm, Uwe; Kondepati, Venkata R.; Mader, J. K.; Ellmerer, M.

    2007-02-01

    Infrared spectroscopy has been successfully employed in multi-component assays for the study of various biomedical samples. Two areas have found particular interest, i.e. in-vitro analysis in the clinical laboratory and point-of-care applications. With regard to the latter field, in-vivo blood glucose monitoring is an important topic for improving glycemic control in critically ill patients with non-adequate blood glucose regulation, similar to the situation faced for diabetic patients. For such application, a continuously operated mid-infrared spectroscopic system in combination with a subcutaneously implanted microdialysis probe and coupled by micro-fluidics has been developed. Using the dialysis process, the interstitial fluid matrix can be significantly simplified, since high molecular mass compounds such as proteins are separated. However, the micro-dialysis recovery rate is variable over time, so that a simultaneous determination of this parameter was implemented using the losses of an acetate marker from the perfusate across the dialysis membrane. Clinical measurements were carried out on type 1 diabetic subjects, with experiments lasting up to 28 hours. The concentrations of glucose, acetate and other components in the dialysates from interstitial body fluids were investigated. Two different multivariate calibration strategies, i.e. partial least squares (PLS) and classical least squares (CLS) regressions were applied. The results led to excellent correlation of the subcutaneous interstitial concentrations with those of laboratory blood glucose readings. Clarke-Error-Grid evaluations were employed for assessing the clinical applicability of the method.

  2. Regulation of hormonal responses of sweet pepper as affected by salinity and elevated CO2 concentration.

    PubMed

    Piñero, María Carmen; Houdusse, Fabrice; Garcia-Mina, Jose M; Garnica, María; Del Amor, Francisco M

    2014-08-01

    This study examines the extent to which the predicted CO2 -protective effects on the inhibition of growth, impairment of photosynthesis and nutrient imbalance caused by saline stress are mediated by an effective adaptation of the endogenous plant hormonal balance. Therefore, sweet pepper plants (Capsicum annuum, cv. Ciclón) were grown at ambient or elevated [CO2] (400 or 800 µmol mol(-1)) with a nutrient solution containing 0 or 80 mM NaCl. The results show that, under saline conditions, elevated [CO2] increased plant dry weight, leaf area, leaf relative water content and net photosynthesis compared with ambient [CO2], whilst the maximum potential quantum efficiency of photosystem II was not modified. In salt-stressed plants, elevated [CO2 ] increased leaf NO3(-) concentration and reduced Cl(-) concentration. Salinity stress induced ABA accumulation in the leaves but it was reduced in the roots at high [CO2], being correlated with the stomatal response. Under non-stressed conditions, IAA was dramatically reduced in the roots when high [CO2] was applied, which resulted in greater root DW and root respiration. Additionally, the observed high CK concentration in the roots (especially tZR) could prevent downregulation of photosynthesis at high [CO2], as the N level in the leaves was increased compared with the ambient [CO2], under salt-stress conditions. These results demonstrate that the hormonal balance was altered by the [CO2], which resulted in significant changes at the growth, gas exchange and nutritional levels. PMID:24152078

  3. A compact photometer based on metal-waveguide-capillary: application to detecting glucose of nanomolar concentration.

    PubMed

    Bai, Min; Huang, Hui; Hao, Jian; Zhang, Ji; Wu, Haibo; Qu, Bo

    2015-01-01

    Trace analysis of liquid samples has wide applications in life science and environmental monitor. In this paper, a compact and low-cost photometer based on metal-waveguide-capillary (MWC) was developed for ultra-sensitive absorbance detection. The optical-path can be greatly enhanced and much longer than the physical length of MWC, because the light scattered by the rippled and smooth metal sidewall can be confined inside the capillary regardless of the incident-angle. For the photometer with a 7 cm long MWC, the detection limit is improved ~3000 fold compared with that of commercial spectrophotometer with 1 cm-cuvette, owing to the novel nonlinear optical-path enhancement as well as fast sample switching, and detecting glucose of a concentration as low as 5.12 nM was realized with conventional chromogenic reagent. PMID:26020222

  4. A compact photometer based on metal-waveguide-capillary: application to detecting glucose of nanomolar concentration

    PubMed Central

    Bai, Min; Huang, Hui; Hao, Jian; Zhang, Ji; Wu, Haibo; Qu, Bo

    2015-01-01

    Trace analysis of liquid samples has wide applications in life science and environmental monitor. In this paper, a compact and low-cost photometer based on metal-waveguide-capillary (MWC) was developed for ultra-sensitive absorbance detection. The optical-path can be greatly enhanced and much longer than the physical length of MWC, because the light scattered by the rippled and smooth metal sidewall can be confined inside the capillary regardless of the incident-angle. For the photometer with a 7 cm long MWC, the detection limit is improved ~3000 fold compared with that of commercial spectrophotometer with 1 cm-cuvette, owing to the novel nonlinear optical-path enhancement as well as fast sample switching, and detecting glucose of a concentration as low as 5.12 nM was realized with conventional chromogenic reagent. PMID:26020222

  5. Multiple-Input Subject-Specific Modeling of Plasma Glucose Concentration for Feedforward Control

    PubMed Central

    2015-01-01

    The ability to accurately develop subject-specific, input causation models, for blood glucose concentration (BGC) for large input sets can have a significant impact on tightening control for insulin dependent diabetes. More specifically, for Type 1 diabetics (T1Ds), it can lead to an effective artificial pancreas (i.e., an automatic control system that delivers exogenous insulin) under extreme changes in critical disturbances. These disturbances include food consumption, activity variations, and physiological stress changes. Thus, this paper presents a free-living, outpatient, multiple-input, modeling method for BGC with strong causation attributes that is stable and guards against overfitting to provide an effective modeling approach for feedforward control (FFC). This approach is a Wiener block-oriented methodology, which has unique attributes for meeting critical requirements for effective, long-term, FFC. PMID:25620845

  6. Polymer optical fiber compound parabolic concentrator tip for enhanced coupling efficiency for fluorescence based glucose sensors

    PubMed Central

    Hassan, Hafeez Ul; Nielsen, Kristian; Aasmul, Soren; Bang, Ole

    2015-01-01

    We demonstrate that the light excitation and capturing efficiency of fluorescence based fiber-optical sensors can be significantly increased by using a CPC (Compound Parabolic Concentrator) tip instead of the standard plane-cut tip. We use Zemax modelling to find the optimum CPC tip profile and fiber length of a polymer optical fiber diabetes sensor for continuous monitoring of glucose levels. We experimentally verify the improved performance of the CPC tipped sensor and the predicted production tolerances. Due to physical size requirements when the sensor has to be inserted into the body a non-optimal fiber length of 35 mm is chosen. For this length an average improvement in efficiency of a factor of 1.7 is experimentally demonstrated and critically compared to the predicted ideal factor of 3 in terms of parameters that should be improved through production optimization. PMID:26713213

  7. Crevice corrosion -- NaCl concentration map for Alloy 625 at elevated temperature

    SciTech Connect

    Amano, Toshiaki; Kojima, Yoichi; Tsujikawa, Shigeo

    1995-12-31

    The repassivation potentials, Er, for metal/metal-crevice of Alloy 625 were determined in 0.3--10% NaCl solutions for temperatures up to 250 C. The ER were found to be the least noble at temperatures around 100 and 125 C. The Er became more noble as temperature increased; this tendency was particularly strong in diluted solutions. Based on the experimental data, a crevice corrosion map showing the critical condition in terms of temperature and NaCl concentration was presented. As for the map, a wide repassivation region was found in elevated temperatures, similar to that of commercially pure titanium, C.P.Ti.

  8. Elevated Glyoxal Concentrations over the Eastern Equatorial Pacific: A Direct Biogenic Source?

    NASA Astrophysics Data System (ADS)

    Zhang, R.; Wang, Y.; Lerot, C.

    2014-12-01

    Elevated atmospheric glyoxal (CHOCHO) was observed over the eastern equatorial Pacific by satellite and ship measurements. We investigated the source contributions through inverse modeling using GOME-2 observations (2007-2012) and the GEOS-Chem model. The observed high glyoxal to HCHO column ratio over the region indicates the potential presence of a direct source of glyoxal rather than secondary production. A bimodal seasonal cycle of glyoxal concentrations was found, providing further evidence for a biogenic origin of glyoxal emission. The estimate of the primary glyoxal emission over the eastern equatorial Pacific is 20-40Tg/yr, which is comparable to the previous estimate of the global continential glyoxal emission.

  9. Elevated synovial fluid concentration of adenosine triphosphate in dogs with osteoarthritis or sodium urate-induced synovitis of the stifle.

    PubMed

    Torres, Bryan T; Jimenez, David A; Budsberg, Steven C

    2016-07-19

    Adenosine triphosphate has been shown to stimulate nociceptive nerve terminals in joints. Elevated synovial fluid adenosine triphosphate concentrations as well as a correlation between synovial fluid adenosine triphosphate concentrations and osteoarthritic knee pain has been demonstrated in humans, but not yet in dogs. This study documented elevated synovial fluid adenosine triphosphate concentrations in the stifles of dogs with secondary osteoarthritis and urate-induced synovitis, as compared to normal stifles. PMID:27432274

  10. Glucose sensing by means of silicon photonics

    NASA Astrophysics Data System (ADS)

    Bockstaele, Ronny; Ryckeboer, Eva; Hattasan, Nannicha; De Koninck, Yannick; Muneeb, Muhammad; Verstuyft, Steven; Delbeke, Danaë; Bogaerts, Wim; Roelkens, Gunther; Baets, Roel

    2014-03-01

    Diabetes is a fast growing metabolic disease, where the patients suffer from disordered glucose blood levels. Monitoring the blood glucose values in combination with extra insulin injection is currently the only therapy to keep the glucose concentration in diabetic patients under control, minimizing the long-term effects of elevated glucose concentrations and improving quality of life of the diabetic patients. Implantable sensors allow continuous glucose monitoring, offering the most reliable data to control the glucose levels. Infrared absorption spectrometers offer a non-chemical measurement method to determine the small glucose concentrations in blood serum. In this work, a spectrometer platform based on silicon photonics is presented, allowing the realization of very small glucose sensors suitable for building implantable sensors. A proof-of-concept of a spectrometer with integrated evanescent sample interface is presented, and the route towards a fully implantable spectrometer is discussed.

  11. Breath concentration of acetic acid vapour is elevated in patients with cystic fibrosis.

    PubMed

    Smith, David; Sovová, Kristýna; Dryahina, Kseniya; Doušová, Tereza; Dřevínek, Pavel; Španěl, Patrik

    2016-01-01

    A study has been carried out of the volatile organic compounds present in the exhaled breath of 58 cystic fibrosis (CF) patients. An important observation is that the acetic acid vapour concentration measured by selected ion flow tube mass spectrometry (SIFT-MS) is significantly elevated in the exhaled breath of CF patients, independent of the Pseudomonas aeruginosa (PA) infection status (PA-infected median 170 ppbv; PA-negative median 182 ppbv), compared to that of healthy controls (median 48 ppbv). The cause for this may be decreased pH of the mucus lining the CF airways. Thus, we speculate that non-invasive measurement of breath acetic acid concentration could serve as an indicator of the acidity of the CF airways mucosa. PMID:27184114

  12. Graphene-Based Fluorescence-Quenching-Related Fermi Level Elevation and Electron-Concentration Surge.

    PubMed

    Lin, Weiyi; Tian, Bo; Zhuang, Pingping; Yin, Jun; Zhang, Cankun; Li, Qiongyu; Shih, Tien-Mo; Cai, Weiwei

    2016-09-14

    Intermolecular p-orbital overlaps in unsaturated π-conjugated systems, such as graphene and fluorescent molecules with aromatic structure, serve as the electron-exchanged path. Using Raman-mapping measurements, we observe that the fluorescence intensity of fluorescein isothiocyanate (FITC) is quenched by graphene, whereas it persists in graphene-absent substrates (SiO2). After identifying a mechanism related to photon-induced electron transfer (PET) that contributes to this fluorescence quenching phenomenon, we validate this mechanism by conducting analyses on Dirac point shifts of FITC-coated graphene. From these shifts, Fermi level elevation and the electron-concentration surge in graphene upon visible-light impingements are acquired. Finally, according to this mechanism, graphene-based biosensors are fabricated to show the sensing capability of measuring fluorescently labeled-biomolecule concentrations. PMID:27513317

  13. Elevated atmospheric carbon dioxide concentration affects interactions between Spodoptera exigua (Lepidoptera: Noctuidae) larvae and two host plant species outdoors

    SciTech Connect

    Caulfield, F.; Bunce, J.A. )

    1994-08-01

    Beet armyworm, Spodoptera exigua (Huebner), larvae were placed on sugarbeet (Beta vulgaris L.) and pigweed (Amaranthus hybridus L.) plants in outdoor chambers in which the plants were growing at either the ambient ([approximately] 350 [mu]l liter[sup [minus]1]) or ambient plus 350 [mu]l liter[sup [minus]1] ([approximately] 700 [mu]l liter[sup [minus]1]) carbon dioxide concentration. A series of experiments was performed to determine if larvae reduced plant growth differently at the two carbon dioxide concentrations in either species and if the insect growth or survival differed with carbon dioxide concentration. Leaf nitrogen, water, starch, and soluble carbohydrate contents were measured to assess carbon dioxide concentration effects on leaf quality. Insect feeding significantly reduced plant growth in sugarbeet plants at 350 [mu]l liter[sup [minus]1] but not at 700 [mu]l liter[sup [minus]1] nor in pigweed at either carbon dioxide concentration. Larval survival was greater on sugarbeet plants at the elevated carbon dioxide concentration. Increased survival occurred only if the insects were at the elevated carbon dioxide concentration and consumed leaf material grown at the elevated concentration. Leaf quality was only marginally affected by growth at elevated carbon dioxide concentration in these experiments. The results indicate that in designing experiments to predict effects of elevated atmospheric carbon dioxide concentrations on plant-insect interactions, both plants and insects should be exposed to the experimental carbon dioxide concentrations, as well as to as realistic environmental conditions as possible.

  14. Relationships between insulin secretion, insulin action, and fasting plasma glucose concentration in nondiabetic and noninsulin-dependent diabetic subjects.

    PubMed Central

    Bogardus, C; Lillioja, S; Howard, B V; Reaven, G; Mott, D

    1984-01-01

    The relationships between insulin secretion, insulin action, and fasting plasma glucose concentration (FPG) were examined in 34 southwest American Indians (19 nondiabetics, 15 noninsulin-dependent diabetics) who had a broad range of FPG (88-310 mg/100 ml). Fasting, glucose-stimulated, and meal-stimulated plasma insulin concentrations were negatively correlated with FPG in diabetics but not in nondiabetics. In contrast, fasting and glucose-stimulated plasma C-peptide concentrations did not decrease with increasing FPG in either group and 24-h urinary C-peptide excretion during a diet of mixed composition was positively correlated with FPG for all subjects (r = 0.36, P less than 0.05). Fasting free fatty acid (FFA) was correlated with FPG in nondiabetics (r = 0.49, P less than 0.05) and diabetics (r = 0.77, P less than 0.001). Fasting FFA was also correlated with the isotopically determined endogenous glucose production rate in the diabetics (r = 0.54, P less than 0.05). Endogenous glucose production was strongly correlated with FPG in the diabetics (r = 0.90, P less than 0.0001), but not in the nondiabetics. Indirect calorimetry showed that FPG was also negatively correlated with basal glucose oxidation rates (r = -0.61, P less than 0.001), but positively with lipid oxidation (r = 0.74, P less than 0.001) in the diabetics. Insulin action was measured as total insulin-mediated glucose disposal, glucose oxidation, and storage rates, using the euglycemic clamp with simultaneous indirect calorimetry at plasma insulin concentrations of 135 +/- 5 and 1738 +/- 59 microU/ml. These parameters of insulin action were significantly, negatively correlated with FPG in the nondiabetics at both insulin concentrations, but not in the diabetics although all the diabetics had markedly decreased insulin action. We conclude that decreased insulin action is present in the noninsulin-dependent diabetics in this population and marked hyperglycemia occurs with the addition of decreased

  15. Elevated anthranilic acid plasma concentrations in type 1 but not type 2 diabetes mellitus

    PubMed Central

    Oxenkrug, Gregory; van der Hart, Marieke; Summergrad, Paul

    2015-01-01

    Experimental data suggested involvement of tryptophan (Trp) – kynurenine (Kyn) pathway (TKP) in mechanisms of autoimmune, type 1 (T1D), and metabolic, type 2 (T2D), diabetes. However, clinical evaluations of TKP metabolites were limited to T2D. We assessed Trp, Kyn and TKP metabolites: anthranilic (AA), kynurenic (KYNA) and xanthurenic (XA) acids, in plasma samples of fifteen T1D, thirty T2D patients and twenty eight non-diabetic subjects by HPLC-mass spectrometry. Trp concentrations were higher in T1D than in T2D and controls while Kyn concentrations were not changed suggesting down-regulation of indoleamine-2,3-dioxygenase (IDO), a rate-limiting enzyme of TKP, in T1D. AA concentrations were 2.3-fold higher in T1D than in T2D and in controls. KYNA and XA concentrations were higher in T1D than in controls, and in previously reported T2D. AA elevation might be a specific feature of T1D. TKP shift towards AA formation in T1D may result from riboflavin deficiency, that increases AA in rats and baboons, and is highly associated with T1D but not T2D. AA augments autoimmune-induced apoptosis of pancreatic cells (PC) by increasing formation of antibodies to PC auto-antigen. Marked increase of AA was reported in rheumatoid arthritis, another autoimmune disorder. Trp, an essential amino acid for humans, is synthesized from AA by diabetogenic intestinal microbiome. AA down-regulates IDO by inhibition of Trp entry into cells. Resulting elevation of Trp attenuates Trp depletion-induced protection of PC against autoimmunity. Further studies of TKP might offer new tools for prevention and treatment of T1D and other autoimmune disorders. PMID:26523229

  16. Elevated Peripheral Blood Plasma Concentrations of Tie-2 and Angiopoietin 2 in Patients with Neuroendocrine Tumors

    PubMed Central

    Melen-Mucha, Gabriela; Niedziela, Agata; Mucha, Slawomir; Motylewska, Ewelina; Lawnicka, Hanna; Komorowski, Jan; Stepien, Henryk

    2012-01-01

    Background Gastro-entero-pancreatic/neuroendocrine (NET) tumors are highly vascularized neoplasms. However, our knowledge concerning circulating levels of the angiogenic factors in NET patients still remains insufficient. Methods The aim of this study was to measure plasma concentrations of VEGF, angiopoietin 1 (Ang-1), angiopoietin 2 (Ang-2), soluble Tie-2, endostatin, osteopontin (OPN) and chromogranin A (CgA) in 36 NET patients and 16 controls. Results Only the plasma concentrations of Tie-2 and CgA were higher in NET patients as compared to controls. These levels were within the reference range in controls; however one control demonstrated slightly elevated Tie-2 and 4 elevated CgA. Similarly, in the subgroup of patients with carcinoid syndrome, only Tie-2 and CgA concentrations were higher than those in patients with non-functioning NETs. In turn, in the subgroup of metastatic patients, only Ang-2 levels were higher than in those with localized disease. A positive correlation was found between Ang-2 and Tie-2 levels in metastatic patients and between Ang-1 and Tie-2 in localized NETs. Conclusions The plasma concentration of Tie-2 is proposed as an additional marker for NET patients and seems to be similarly effective as the currently used CgA level. Moreover, higher plasma levels of Ang-2 together with the positive correlation between Ang-2 and Tie-2 levels in metastatic subjects, implies that cases with a Tie-2 level above the upper limits, together with higher level of Ang-2 seem to be highly predictive of metastases. PMID:22408401

  17. The use of Fourier-transform infrared spectroscopy for the quantitative determination of glucose concentration in whole blood.

    PubMed

    Shen, Y C; Davies, A G; Linfleld, E H; Elsey, T S; Taday, P F; Arnone, D D

    2003-07-01

    Fourier-transform infrared transmission spectroscopy has been used for the determination of glucose concentration in whole blood samples from 28 patients. A 4-vector partial least-squares calibration model, using the spectral range 950-1200 cm(-1), yielded a standard-error-of-prediction of 0.59 mM for an independent test set. For blood samples from a single patient, we found that the glucose concentration was proportional to the difference between the values of the second derivative spectrum at 1082 cm(-1) and 1093 cm(-1). This indicates that spectroscopy at these two specific wavenumbers alone could be used to determine the glucose concentration in blood plasma samples from a single patient, with a prediction error of 0.95 mM. PMID:12884933

  18. Organic phosphorus mineralisation in a temperate grassland soil under elevated atmospheric carbon dioxide concentrations

    NASA Astrophysics Data System (ADS)

    Jarosch, Klaus A.; Andresen, Louise; Gorenflo, André D.; Müller, Christoph; Frossard, Emmanuel; Bünemann, Else K.

    2016-04-01

    Background: Phosphorus (P) is an essential nutrient for all biota and significant proportions of P in soil are present in organic form. Increased atmospheric concentrations of carbon dioxide ([CO2]) have been shown to influence plant P uptake traits, resulting in plant-mediated changes in soil P pools. However, little is known on the effect of elevated [CO2] on organic P mineralisation rates in soil. Study design & hypotheses: A 33P isotopic dilution experiment was performed with soils of the 17-year-old Giessen free air carbon dioxide enrichment (GiFACE) - trial. At the GiFACE, three plots are treated with 20 % elevated [CO2] while three control plots receive ambient air. We hypothesised that i) the observed positive effect of elevated [CO2] on plant growth translates into differences in soil organic P mineralisation rates between treated and untreated plots, resulting in ii) differences in soil organic P pools. Methods: Fresh soil (0-8 cm) was sampled from each plot, labelled with a carrier free 33P solution and incubated for 36 days at 19° C in the dark. On six time points, inorganic P and 33P in soil filtrates, soil microorganisms (by liquid fumigation) and resin extractable P were quantified. The baseline of 33P isotopic dilution was assessed from a short term batch experiment and extrapolated for 36 days. Gross organic P mineralisation rates were determined as the difference between isotopic dilution in the incubated soils (physicochemical + biological processes) minus extrapolated values (physicochemical processes only). Additionally, enzyme addition assays on alkaline soil extracts were performed to quantify different soil organic P classes, using enzymes with a known substrate specificity. Results & Discussion: Gross organic P mineralisation rates were high during the first three days (5.5 - 34.3 mg P kg‑1 d‑1), possibly due to the soil disturbance at labelling soils with 33P. However, gross organic P mineralisation decreased rapidly to rates between

  19. Blood and urine responses to ingesting fluids of various salt and glucose concentrations. [to combat orthostatic intolerance

    NASA Technical Reports Server (NTRS)

    Frey, Mary A.; Riddle, Jeanne; Charles, John B.; Bungo, Michael W.

    1991-01-01

    To compensate for the reduced blood and fluid volumes that develop during weightlessness, the Space Shuttle crewmembers consume salt tablets and water equivalent to 1 l of normal saline, about 2 hrs before landing. This paper compares the effects on blood, urine, and cardiovascular variables of the ingestion of 1 l of normal (0.9 percent) saline with the effects of distilled water, 1 percent glucose, 0.74 percent saline with 1 percent glucose, 0.9 percent saline with 1 percent glucose, and 1.07 percent saline. It was found that the expansion of plasma volume and the concentration of urine were greater 4 hrs after ingestion of 1.07 percent saline solution than after ingestion of normal saline and that the solutions containig glucose did not enhance any variables as compared with normal saline.

  20. Elevated Lung Cancer in Younger Adults and Low Concentrations of Arsenic in Water

    PubMed Central

    Steinmaus, Craig; Ferreccio, Catterina; Yuan, Yan; Acevedo, Johanna; González, Francisca; Perez, Liliana; Cortés, Sandra; Balmes, John R.; Liaw, Jane; Smith, Allan H.

    2014-01-01

    Arsenic concentrations greater than 100 µg/L in drinking water are a known cause of cancer, but the risks associated with lower concentrations are less well understood. The unusual geology and good information on past exposure found in northern Chile are key advantages for investigating the potential long-term effects of arsenic. We performed a case-control study of lung cancer from 2007 to 2010 in areas of northern Chile that had a wide range of arsenic concentrations in drinking water. Previously, we reported evidence of elevated cancer risks at arsenic concentrations greater than 100 µg/L. In the present study, we restricted analyses to the 92 cases and 288 population-based controls who were exposed to concentrations less than 100 µg/L. After adjustment for age, sex, and smoking behavior, these exposures from 40 or more years ago resulted in odds ratios for lung cancer of 1.00, 1.43 (90% confidence interval: 0.82, 2.52), and 2.01 (90% confidence interval: 1.14, 3.52) for increasing tertiles of arsenic exposure, respectively (P for trend = 0.02). Mean arsenic water concentrations in these tertiles were 6.5, 23.0, and 58.6 µg/L. For subjects younger than 65 years of age, the corresponding odds ratios were 1.00, 1.62 (90% confidence interval: 0.67, 3.90), and 3.41 (90% confidence interval: 1.51, 7.70). Adjustments for occupation, fruit and vegetable intake, and socioeconomic status had little impact on the results. These findings provide new evidence that arsenic water concentrations less than 100 µg/L are associated with higher risks of lung cancer. PMID:25371173

  1. Elevated lung cancer in younger adults and low concentrations of arsenic in water.

    PubMed

    Steinmaus, Craig; Ferreccio, Catterina; Yuan, Yan; Acevedo, Johanna; González, Francisca; Perez, Liliana; Cortés, Sandra; Balmes, John R; Liaw, Jane; Smith, Allan H

    2014-12-01

    Arsenic concentrations greater than 100 µg/L in drinking water are a known cause of cancer, but the risks associated with lower concentrations are less well understood. The unusual geology and good information on past exposure found in northern Chile are key advantages for investigating the potential long-term effects of arsenic. We performed a case-control study of lung cancer from 2007 to 2010 in areas of northern Chile that had a wide range of arsenic concentrations in drinking water. Previously, we reported evidence of elevated cancer risks at arsenic concentrations greater than 100 µg/L. In the present study, we restricted analyses to the 92 cases and 288 population-based controls who were exposed to concentrations less than 100 µg/L. After adjustment for age, sex, and smoking behavior, these exposures from 40 or more years ago resulted in odds ratios for lung cancer of 1.00, 1.43 (90% confidence interval: 0.82, 2.52), and 2.01 (90% confidence interval: 1.14, 3.52) for increasing tertiles of arsenic exposure, respectively (P for trend = 0.02). Mean arsenic water concentrations in these tertiles were 6.5, 23.0, and 58.6 µg/L. For subjects younger than 65 years of age, the corresponding odds ratios were 1.00, 1.62 (90% confidence interval: 0.67, 3.90), and 3.41 (90% confidence interval: 1.51, 7.70). Adjustments for occupation, fruit and vegetable intake, and socioeconomic status had little impact on the results. These findings provide new evidence that arsenic water concentrations less than 100 µg/L are associated with higher risks of lung cancer. PMID:25371173

  2. Utility of Glycated Hemoglobin for Assessment of Glucose Metabolism in Patients With ST-Segment Elevation Myocardial Infarction.

    PubMed

    Aggarwal, Bhuvnesh; Shah, Gautam K; Randhawa, Mandeep; Ellis, Stephen G; Lincoff, Abraham Michael; Menon, Venu

    2016-03-01

    Glycated hemoglobin (HbA1c) is an approved and widely used laboratory investigation for diagnosis of diabetes that is not affected by acute changes in blood glucose. Our aim was to analyze the extent to which routine HbA1c measurements diagnose unknown diabetes mellitus (DM) in patients presenting with ST-segment elevation myocardial infarction (STEMI). We also compared outcomes in patients with newly diagnosed DM, previously established DM and those without DM. Consecutive patients undergoing PCI for STEMI from January 2005 to December 2012 were included and routinely performed admission HbA1c was used to identify patients with previously undiagnosed DM (HbA1c ≥6.5 and no history of DM or DM therapy) and pre-DM (HbA1c 5.7% to 6.4%). Overall 1,686 consecutive patients underwent primary percutaneous coronary intervention for STEMI during the study period and follow-up data were available for 1,566 patients (90%). A quarter of the patients (24%, n = 405) had history of DM, 7% (n = 118) had previously undiagnosed DM, and 38.7% (n = 652) had pre-DM. Mortality was comparable in patients with known DM and newly diagnosed DM both in-hospital (11.1% vs 11.9%, p = 0.87) and at 3-year follow-up (27.3% and 24%). Patients with DM, including those who were newly diagnosed, had higher mortality at 3 years (26.5%) compared to those with pre-DM (12.1%) or no dysglycemia (11.2%, p <0.01). In conclusion, a substantial number of patients with STEMI have previously undiagnosed DM (7%). These patients have similar in-hospital and long-term mortality as those with known DM, and outcomes are inferior to patients without dysglycemia. PMID:26768673

  3. In vivo exercise followed by in vitro contraction additively elevates subsequent insulin-stimulated glucose transport by rat skeletal muscle.

    PubMed

    Funai, Katsuhiko; Schweitzer, George G; Castorena, Carlos M; Kanzaki, Makoto; Cartee, Gregory D

    2010-05-01

    The cellular mechanisms whereby prior exercise enhances insulin-stimulated glucose transport (GT) are not well understood. Previous studies suggested that a prolonged increase in phosphorylation of Akt substrate of 160 kDa (AS160) may be important for the postexercise increase in insulin sensitivity. In the current study, the effects of in vivo exercise and in vitro contraction on subsequent insulin-stimulated GT were studied separately and together. Consistent with results from previous studies, prior exercise resulted in an increase in AS160 (642)Thr phosphorylation immediately after exercise in rat epitrochlearis muscles, and this increase remained 3 h postexercise concomitant with enhanced insulin-stimulated GT. For experiments with in vitro contraction, isolated rat epitrochlearis muscles were electrically stimulated to contract in the presence or absence of rat serum. As expected, insulin-stimulated GT measured 3 h after electrical stimulation in serum, but not after electrical stimulation without serum, exceeded resting controls. Immediately after electrical stimulation with or without serum, phosphorylation of both AS160 (detected by phospho-Akt substrate, PAS, antibody, or phospho-(642)Thr antibody) and its paralog TBC1D1 (detected by phospho-(237)Ser antibody) was increased. However, both AS160 and TBC1D1 phosphorylation had reversed to resting values at 3 h poststimulation with or without serum. Increasing the amount of exercise (from 1 to 2 h) or electrical stimulation (from 5 to 10 tetani) did not further elevate insulin-stimulated GT. In contrast, the combination of prior exercise and electrical stimulation had an additive effect on the subsequent increase in insulin-stimulated GT, suggesting that these exercise and electrical stimulation protocols may amplify insulin-stimulated GT through distinct mechanisms, with a persistent increase in AS160 phosphorylation potentially important for increased insulin sensitivity after exercise, but not after in

  4. Elevated glucocorticoid concentrations during gestation predict reduced reproductive success in subordinate female banded mongooses.

    PubMed

    Sanderson, J L; Nichols, H J; Marshall, H H; Vitikainen, E I K; Thompson, F J; Walker, S L; Cant, M A; Young, A J

    2015-10-01

    Dominant females in social species have been hypothesized to reduce the reproductive success of their subordinates by inducing elevated circulating glucocorticoid (GC) concentrations. However, this 'stress-related suppression' hypothesis has received little support in cooperatively breeding species, despite evident reproductive skews among females. We tested this hypothesis in the banded mongoose (Mungos mungo), a cooperative mammal in which multiple females conceive and carry to term in each communal breeding attempt. As predicted, lower ranked females had lower reproductive success, even among females that carried to term. While there were no rank-related differences in faecal glucocorticoid (fGC) concentrations prior to gestation or in the first trimester, lower ranked females had significantly higher fGC concentrations than higher ranked females in the second and third trimesters. Finally, females with higher fGC concentrations during the third trimester lost a greater proportion of their gestated young prior to their emergence from the burrow. Together, our results are consistent with a role for rank-related maternal stress in generating reproductive skew among females in this cooperative breeder. While studies of reproductive skew frequently consider the possibility that rank-related stress reduces the conception rates of subordinates, our findings highlight the possibility of detrimental effects on reproductive outcomes even after pregnancies have become established. PMID:26510673

  5. Elevated glucocorticoid concentrations during gestation predict reduced reproductive success in subordinate female banded mongooses

    PubMed Central

    Sanderson, J. L.; Nichols, H. J.; Marshall, H. H.; Vitikainen, E. I. K.; Thompson, F. J.; Walker, S. L.; Cant, M. A.; Young, A. J.

    2015-01-01

    Dominant females in social species have been hypothesized to reduce the reproductive success of their subordinates by inducing elevated circulating glucocorticoid (GC) concentrations. However, this ‘stress-related suppression' hypothesis has received little support in cooperatively breeding species, despite evident reproductive skews among females. We tested this hypothesis in the banded mongoose (Mungos mungo), a cooperative mammal in which multiple females conceive and carry to term in each communal breeding attempt. As predicted, lower ranked females had lower reproductive success, even among females that carried to term. While there were no rank-related differences in faecal glucocorticoid (fGC) concentrations prior to gestation or in the first trimester, lower ranked females had significantly higher fGC concentrations than higher ranked females in the second and third trimesters. Finally, females with higher fGC concentrations during the third trimester lost a greater proportion of their gestated young prior to their emergence from the burrow. Together, our results are consistent with a role for rank-related maternal stress in generating reproductive skew among females in this cooperative breeder. While studies of reproductive skew frequently consider the possibility that rank-related stress reduces the conception rates of subordinates, our findings highlight the possibility of detrimental effects on reproductive outcomes even after pregnancies have become established. PMID:26510673

  6. Glucose, fructose and sucrose increase the solubility of protein-tannin complexes and at high concentration, glucose and sucrose interfere with bisulphite bleaching of wine pigments.

    PubMed

    Harbertson, James F; Yuan, Chunlong; Mireles, Maria S; Hanlin, Rachel L; Downey, Mark O

    2013-05-01

    Wines were modified with increasing sugar concentrations and decreasing tannin concentrations and analysed by a combination of protein precipitation and bisulphite bleaching. Increasing sugar concentration decreased the precipitation of tannin and protein-precipitable polymeric pigments (PPP). The use of a hydrogen bond disruptor (urea) to reduce protein-tannin and protein-pigment complex formation showed that the effect of sugar concentration occurred by increasing the solubility of the tannin-protein complex, not by interfering with protein-tannin complex formation. By increasing the solubility of pigment-protein complexes, non-protein-precipitable polymeric pigments (nPPP) appeared to increase. There was also an increase in total polymeric pigments at each tannin concentration with increasing glucose and sucrose concentration, indicating that sugar concentration might also affect bisulphite bleaching of wine pigments. While a significant effect of sugar concentration on tannin-protein complex solubility was observed, these effects were greatest at sugar concentrations far in excess of normal wine making conditions. Under normal wine making conditions, sugar concentration will have a negligible effect on protein-precipitable tannin, PPP and nPPP concentrations. PMID:23265524

  7. Blood glucose levels, insulin concentrations, and insulin resistance in healthy women and women with premenstrual syndrome: a comparative study

    PubMed Central

    Zarei, Safar; Mosalanejad, Leili

    2013-01-01

    Objective To compare the blood glucose levels, insulin concentrations, and insulin resistance during the two phases of the menstrual cycle between healthy women and patients with premenstrual syndrome (PMS). Methods From January of 2011 to the August of 2012, a descriptive cross-sectional study was performed among students in the School of Medicine of Jahrom University of Medical Sciences. We included 30 students with the most severe symptoms of PMS and 30 age frequency-matched healthy controls. We analyzed the serum concentrations of glucose, insulin, and insulin resistance by using the glucose oxidase method, radioimmunometric assay, and homeostasis model assessment of insulin resistance equation, respectively. Results No significant differences between the demographic data of the control and PMS groups were observed. The mean concentrations of glucose of the two study groups were significantly different during the follicular and luteal phases (p=0.011 vs. p<0.0001, respectively). The amounts of homeostasis model assessment of insulin resistance of the two study groups were significantly different in the luteal phase (p=0.0005). Conclusion The level of blood glucose and insulin resistance was lower during the two phases of the menstrual cycle of the PMS group than that of the controls. PMID:23875163

  8. Potential ecotoxicological significance of elevated concentrations of strontium in eggshells of passerine birds

    USGS Publications Warehouse

    Mora, Miguel A.; Taylor, Robert J.; Brattin, Bryan L.

    2007-01-01

    We investigated the occurrence and potential ecotoxicological significance of elevated concentrations of strontium (Sr) in eggshells of nine passerine birds from four regions in Arizona. Concentrations of Sr in eggshells ranged from 70 to 1360 µg g−1 dry weight (overall mean  =  684 ± 345 SD µg g−1 dw) for the four regions. 23% of the eggshells had Sr concentrations greater than 1000 µg g−1 dw. To our knowledge, these are among the highest levels of Sr that have been reported in bird eggshells in North America. Of the nine species, Brown-headed Cowbirds (Molothrus ater) had the greatest concentrations of Sr. There was a significant positive correlation between Sr and calcium (Ca), and between barium (Ba) and Ca. Ca, Sr, and Ba interact with each other and can exert similar chemical and pharmacological effects. Mean (n ≥ 3) eggshell∶egg ratios for Sr varied with species and ranged from 6.1∶1 to 40.2∶1; ratios for individual eggs reached 92.7∶1. Mean Sr/Ca values ranged from 1.3 × 10−3 to 3.0 × 10−3 and mean eggshell thickness ranged from 83 ± 6 to 120 ± 9 µm for all species. Eggshell thickness was not significantly correlated with Sr for any species but tended to increase with Sr concentrations. We postulate that high concentrations of Sr in the shell could affect later-stage embryos by possible interference with Ca metabolism and bone growth, resulting in reduced hatching success and potential minor beak deformities.

  9. Measurements of the Concentration and Composition of CCN and IN at a High Elevation Site

    NASA Astrophysics Data System (ADS)

    Friedman, B.; Kulkarni, G.; Zelenyuk, A.; Beranek, J.; Pekour, M. S.; Hallar, A. G.; Mccubbin, I. B.; Cziczo, D. J.; Thornton, J. A.

    2011-12-01

    Field measurements of cloud condensation nuclei (CCN) and ice nuclei (IN) were conducted in March 2011 at Storm Peak Laboratory (elevation 3220 m m.s.l.). Measurements of CCN number concentrations and droplet size distributions at supersaturations of 0.05%, 0.1%, 0.2%, 0.4%, and 0.7% were conducted in parallel with Scanning Mobility Particle Sizer (SMPS) measurements of size distributions and number concentrations of ambient particles. SMPS number concentrations of the overall ambient aerosol population were used to calculate the fraction of particles activating as droplets at the supersaturations studied. Single Particle Mass Spectrometer (SPLAT II) was used to characterize number concentration, size, internal composition, and densities of individual particles present in the ambient air. In a separate set of experiments, a pumped counterflow virtual impactor (PCVI) was used to separate particles that activated as CCN from unactivated particles, using a 50% cutsize of approximately 2.5 microns. The droplet residuals from the activated particles were characterized by SPLAT and compared to the properties of the overall aerosol population in order to examine the effect of single particle mixing state, aerosol composition, and size on CCN activity as a function of supersaturation. The PNNL Compact Ice Chamber (CIC) was deployed to measure IN concentrations and ice crystal size distributions at temperatures ranging from 253K to 233K. SMPS number concentrations, size distributions, and SPLAT single particle measurements were also utilized to assess the ice nucleation properties of ambient particles as a function of the processing conditions in the PNNL CIC.

  10. Responses of mature loblolly pine trees to elevated CO[sub 2] concentrations

    SciTech Connect

    Lie, S.; Teskey, R.O. )

    1993-06-01

    The direct responses of mature loblolly pine (Pinus taeda) foliage to increasing atmospheric CO[sub 2] were investigated in six 18-year-old loblolly pine trees using the branch-chamber technique. On each tree, six main branches were randomly selected and each enclosed in one of six chambers. Each branch received one of the following six treatments: ambient CO[sub 2]/ambient temperature (1), 1.5 x ambient CO[sub 2] ambient temperature (2), 2.0 x ambient CO[sub 2]/ambient temperature (3), ambient CO[sub 2]/2.0[degrees]C + ambient temperature (4), 1.5 x ambient CO[sub 2]/2.0[degree]C + ambient temperature (5) and 2.0 x ambient CO[sub 2]/2.0[degree]C + ambient temperature (6). A/C, curves were run and P- (photosynthetic rate at saturating light) of the current year, first flush needles was measured at each respective treatment CO[sub 2] level for treatments 1, 2 and 3 using the Li-cor 6200 photosynthesis system. Both elevated CO[sub 2] concentrations significantly increased the photosynthesis of the foliage of the mature loblolly pine trees. However, comparison of the slopes of the initial linear part of the A/C[sub 1], curves suggested no reduction in the rubisco carboxylation activity. Additionally, there was no indication of photosynthetic acclimation to elevated CO[sub 2].

  11. Changes in root architecture under elevated concentrations of CO₂ and nitrogen reflect alternate soil exploration strategies.

    PubMed

    Beidler, Katilyn V; Taylor, Benton N; Strand, Allan E; Cooper, Emily R; Schönholz, Marcos; Pritchard, Seth G

    2015-02-01

    Predicting the response of fine roots to increased atmospheric CO₂ concentration has important implications for carbon (C) and nutrient cycling in forest ecosystems. Root architecture is known to play an important role in how trees acquire soil resources in changing environments. However, the effects of elevated CO₂ on the fine-root architecture of trees remain unclear. We investigated the architectural response of fine roots exposed to 14 yr of CO₂ enrichment and 6 yr of nitrogen (N) fertilization in a Pinus taeda (loblolly pine) forest. Root traits reflecting geometry, topology and uptake function were measured on intact fine-root branches removed from soil monoliths and the litter layer. CO₂ enrichment resulted in the development of a fine-root pool that was less dichotomous and more exploratory under N-limited conditions. The per cent mycorrhizal colonization did not differ among treatments, suggesting that root growth and acclimation to elevated CO₂ were quantitatively more important than increased mycorrhizal associations. Our findings emphasize the importance of architectural plasticity in response to environmental change and suggest that changes in root architecture may allow trees to effectively exploit larger volumes of soil, thereby pre-empting progressive nutrient limitations. PMID:25348775

  12. Observations of the uptake of carbonyl sulfide (COS) by trees under elevated atmospheric carbon dioxide concentrations

    NASA Astrophysics Data System (ADS)

    Sandoval-Soto, L.; Kesselmeier, M.; Schmitt, V.; Wild, A.; Kesselmeier, J.

    2012-02-01

    Global change affects ecosystems to adapt to elevated atmospheric concentrations of carbon dioxide (CO2). We understand that carbonyl sulfide (COS), a trace gas which is involved in building up the stratospheric sulfate aerosol layer, is taken up by vegetation with the same triad of the enzmyes which are metabolizing the CO2, i.e. Ribulose-1,5-bisphosphate Carboxylase-Oxygenase (Rubisco), Phosphoenolpyruvate Carboxylase (PEP-Co) and carbonic anhydrase (CA). Therefore, we discuss a physiological/biochemical adaptation of these enzymes to affect the sink strength of vegetation for COS. We investigated the adaption of two European tree species, Fagus sylvatica and Quercus ilex, grown inside chambers under elevated CO2 and determined the exchange characteristics and the content of CA after a 1-2 yr period of adaption from 350 ppm to 800 ppm CO2. We could demonstrate that the COS compensation point, the CA activity and the deposition velocities may change and cause a decrease of the COS uptake by plant ecosystems. As a consequence, the atmospheric COS level may rise leading to higher input of this trace gas into the stratosphere and causing a higher energy reflection by the stratospheric sulfur aerosol into space, thus counteracting the direct radiative forcing by the tropospheric COS.

  13. Effects of long-term elevated atmospheric CO{sub 2} concentrations on Pinus ponderosa

    SciTech Connect

    Surano, K.A.; Kercher, J.R.

    1993-10-01

    This report details the results from an experiment of the effects of long-term elevated atmospheric CO{sub 2} concentrations on ponderosa pine (Pinus ponderosa Laws.) saplings and seedlings. The study began in 1983 as a pilot study designed to explore the feasibility of using open-top chambers for continuous multi-year exposures on sapling-sized trees and to examine possible CO{sub 2} responses so that future research could be adequately designed. however, following the first year of exposure, preliminary results from the study indicated that measurements of CO{sub 2} responses should be intensified. Open-top chambers proved suitable for use in multiyear exposures of mature trees. With respect to the preliminary examination of CO{sub 2} responses, many interesting observations were made. The nature of the preliminary results suggests that future long-term field CO{sub 2} exposures on perennial species may be critical to the understanding and preparation for future environments. Other research reported here attempted to adapt an existing western coniferous forest growth and succession model for use in elevated CO{sub 2} scenarios using differential species responses, and assessed the usefulness of the model in that regard. Seven papers have been processed separately for inclusion in the appropriate data bases.

  14. Growth at elevated ozone or elevated carbon dioxide concentration alters antioxidant capacity and response to acute oxidative stress in soybean (Glycine max)

    SciTech Connect

    Gillespie, K.M.; Rogers, A.; Ainsworth, E. A.

    2011-01-31

    Soybeans (Glycine max Merr.) were grown at elevated carbon dioxide concentration ([CO{sub 2}]) or chronic elevated ozone concentration ([O{sub 3}]; 90 ppb), and then exposed to an acute O{sub 3} stress (200 ppb for 4 h) in order to test the hypothesis that the atmospheric environment alters the total antioxidant capacity of plants, and their capacity to respond to an acute oxidative stress. Total antioxidant metabolism, antioxidant enzyme activity, and antioxidant transcript abundance were characterized before, immediately after, and during recovery from the acute O{sub 3} treatment. Growth at chronic elevated [O{sub 3}] increased the total antioxidant capacity of plants, while growth at elevated [CO{sub 2}] decreased the total antioxidant capacity. Changes in total antioxidant capacity were matched by changes in ascorbate content, but not phenolic content. The growth environment significantly altered the pattern of antioxidant transcript and enzyme response to the acute O{sub 3} stress. Following the acute oxidative stress, there was an immediate transcriptional reprogramming that allowed for maintained or increased antioxidant enzyme activities in plants grown at elevated [O{sub 3}]. Growth at elevated [CO{sub 2}] appeared to increase the response of antioxidant enzymes to acute oxidative stress, but dampened and delayed the transcriptional response. These results provide evidence that the growth environment alters the antioxidant system, the immediate response to an acute oxidative stress, and the timing over which plants return to initial antioxidant levels. The results also indicate that future elevated [CO{sub 2}] and [O{sub 3}] will differentially affect the antioxidant system.

  15. Aggregate structure, morphology and the effect of aggregation mechanisms on viscosity at elevated protein concentrations.

    PubMed

    Barnett, Gregory V; Qi, Wei; Amin, Samiul; Neil Lewis, E; Roberts, Christopher J

    2015-12-01

    Non-native aggregation is a common issue in a number of degenerative diseases and during manufacturing of protein-based therapeutics. There is a growing interest to monitor protein stability at intermediate to high protein concentrations, which are required for therapeutic dosing of subcutaneous injections. An understanding of the impact of protein structural changes and interactions on the protein aggregation mechanisms and resulting aggregate size and morphology may lead to improved strategies to reduce aggregation and solution viscosity. This report investigates non-native aggregation of a model protein, α-chymotrypsinogen, under accelerated conditions at elevated protein concentrations. Far-UV circular dichroism and Raman scattering show structural changes during aggregation. Size exclusion chromatography and laser light scattering are used to monitor the progression of aggregate growth and monomer loss. Monomer loss is concomitant with increased β-sheet structures as monomers are added to aggregates, which illustrate a transition from a native monomeric state to an aggregate state. Aggregates grow predominantly through monomer-addition, resulting in a semi-flexible polymer morphology. Analysis of aggregation growth kinetics shows that pH strongly affects the characteristic timescales for nucleation (τn) and growth (τg), while the initial protein concentration has only minor effects on τn or τg. Low-shear viscosity measurements follow a common scaling relationship between average aggregate molecular weight (Mw(agg)) and concentration (σ), which is consistent with semi-dilute polymer-solution theory. The results establish a link between aggregate growth mechanisms, which couple Mw(agg) and σ, to increases in solution viscosity even at these intermediate protein concentrations (less than 3w/v %). PMID:26284891

  16. Gas diffusion electrode setup for catalyst testing in concentrated phosphoric acid at elevated temperatures

    SciTech Connect

    Wiberg, Gustav K. H. E-mail: m.arenz@chem.ku.dk; Fleige, Michael; Arenz, Matthias E-mail: m.arenz@chem.ku.dk

    2015-02-15

    We present a detailed description of the construction and testing of an electrochemical cell setup allowing the investigation of a gas diffusion electrode containing carbon supported high surface area catalysts. The setup is designed for measurements in concentrated phosphoric acid at elevated temperature, i.e., very close to the actual conditions in high temperature proton exchange membrane fuel cells (HT-PEMFCs). The cell consists of a stainless steel flow field and a PEEK plastic cell body comprising the electrochemical cell, which exhibits a three electrode configuration. The cell body and flow field are braced using a KF-25 vacuum flange clamp, which allows an easy assembly of the setup. As demonstrated, the setup can be used to investigate temperature dependent electrochemical processes on high surface area type electrocatalysts, but it also enables quick screening tests of HT-PEMFC catalysts under realistic conditions.

  17. Responses of Saccharomyces cerevisiae Strains from Different Origins to Elevated Iron Concentrations

    PubMed Central

    Martínez-Garay, Carlos Andrés; de Llanos, Rosa; Romero, Antonia María; Martínez-Pastor, María Teresa

    2016-01-01

    Iron is an essential micronutrient for all eukaryotic organisms. However, the low solubility of ferric iron has tremendously increased the prevalence of iron deficiency anemia, especially in women and children, with dramatic consequences. Baker's yeast Saccharomyces cerevisiae is used as a model eukaryotic organism, a fermentative microorganism, and a feed supplement. In this report, we explore the genetic diversity of 123 wild and domestic strains of S. cerevisiae isolated from different geographical origins and sources to characterize how yeast cells respond to elevated iron concentrations in the environment. By using two different forms of iron, we selected and characterized both iron-sensitive and iron-resistant yeast strains. We observed that when the iron concentration in the medium increases, iron-sensitive strains accumulate iron more rapidly than iron-resistant isolates. We observed that, consistent with excess iron leading to oxidative stress, the redox state of iron-sensitive strains was more oxidized than that of iron-resistant strains. Growth assays in the presence of different oxidative reagents ruled out that this phenotype was due to alterations in the general oxidative stress protection machinery. It was noteworthy that iron-resistant strains were more sensitive to iron deficiency conditions than iron-sensitive strains, which suggests that adaptation to either high or low iron is detrimental for the opposite condition. An initial gene expression analysis suggested that alterations in iron homeostasis genes could contribute to the different responses of distant iron-sensitive and iron-resistant yeast strains to elevated environmental iron levels. PMID:26773083

  18. Elevated atmospheric CO 2 concentration and temperature across an urban-rural transect

    NASA Astrophysics Data System (ADS)

    George, K.; Ziska, L. H.; Bunce, J. A.; Quebedeaux, B.

    The heat island effect and the high use of fossil fuels in large city centers are well documented, but by how much fossil fuel consumption is elevating atmospheric CO 2 concentrations and whether elevations in both atmospheric CO 2 and air temperature from rural to urban areas are consistently different from year to year are less well known. Our aim was to record atmospheric CO 2 concentrations, air temperature and other environmental variables in an urban area and compare it to suburban and rural sites to see if urban sites are experiencing climates expected globally in the future with climate change. A transect was established from Baltimore city center (Urban site), to the outer suburbs of Baltimore (suburban site) and out to an organic farm (rural site). At each site a weather station was set-up to monitor environmental variables for 5 years. Atmospheric CO 2 was consistently and significantly increased on average by 66 ppm from the rural to the urban site over the 5 years of the study. Air temperature was also consistently and significantly higher at the urban site (14.8 °C) compared to the suburban (13.6 °C) and rural (12.7 °C) sites. Relative humidity was not different between sites whereas the vapor pressure deficit (VPD) was significantly higher at the urban site compared to the suburban and rural sites. An increase in nitrogen deposition at the rural site of 0.6% and 1.0% compared to the suburban and urban sites was small enough not to affect soil nitrogen content. Dense urban areas with large populations and high vehicular traffic have significantly different microclimates compared to outlying suburban and rural areas. The increases in atmospheric CO 2 and air temperature are similar to changes predicted in the short term with global climate change, therefore providing an environment suitable for studying future effects of climate change on terrestrial ecosystems.

  19. Responses of Saccharomyces cerevisiae Strains from Different Origins to Elevated Iron Concentrations.

    PubMed

    Martínez-Garay, Carlos Andrés; de Llanos, Rosa; Romero, Antonia María; Martínez-Pastor, María Teresa; Puig, Sergi

    2016-03-01

    Iron is an essential micronutrient for all eukaryotic organisms. However, the low solubility of ferric iron has tremendously increased the prevalence of iron deficiency anemia, especially in women and children, with dramatic consequences. Baker's yeast Saccharomyces cerevisiae is used as a model eukaryotic organism, a fermentative microorganism, and a feed supplement. In this report, we explore the genetic diversity of 123 wild and domestic strains of S. cerevisiae isolated from different geographical origins and sources to characterize how yeast cells respond to elevated iron concentrations in the environment. By using two different forms of iron, we selected and characterized both iron-sensitive and iron-resistant yeast strains. We observed that when the iron concentration in the medium increases, iron-sensitive strains accumulate iron more rapidly than iron-resistant isolates. We observed that, consistent with excess iron leading to oxidative stress, the redox state of iron-sensitive strains was more oxidized than that of iron-resistant strains. Growth assays in the presence of different oxidative reagents ruled out that this phenotype was due to alterations in the general oxidative stress protection machinery. It was noteworthy that iron-resistant strains were more sensitive to iron deficiency conditions than iron-sensitive strains, which suggests that adaptation to either high or low iron is detrimental for the opposite condition. An initial gene expression analysis suggested that alterations in iron homeostasis genes could contribute to the different responses of distant iron-sensitive and iron-resistant yeast strains to elevated environmental iron levels. PMID:26773083

  20. Blood glucose concentration and risk of pancreatic cancer: systematic review and dose-response meta-analysis

    PubMed Central

    Liao, Wei-Chih; Wu, Ming-Shiang; Lin, Jaw-Town; Wang, Hsiu-Po

    2015-01-01

    Objective To evaluate potential linear and non-linear dose-response relations between blood glucose and risk of pancreatic cancer. Design Systematic review and dose-response meta-analysis of prospective observational studies. Data sources Search of PubMed, Scopus, and related reviews before 30 November 2013 without language restriction. Eligibility criteria Prospective studies evaluating the association between blood glucose concentration and pancreatic cancer. Retrospective and cross sectional studies excluded to avoid reverse causality. Data extraction and synthesis Two reviewers independently extracted relevant information and assessed study quality with the Newcastle-Ottawa scale. Random effects dose-response meta-analysis was conducted to assess potential linear and non-linear dose-response relations. Results Nine studies were included for analysis, with a total of 2408 patients with pancreatic cancer. There was a strong linear dose-response association between fasting blood glucose concentration and the rate of pancreatic cancer across the range of prediabetes and diabetes. No non-linear association was detected. The pooled rate ratio of pancreatic cancer per 0.56 mmol/L (10 mg/dL) increase in fasting blood glucose was 1.14 (95% confidence interval 1.06 to 1.22; P<0.001) without significant heterogeneity. Sensitivity analysis excluding blood glucose categories in the range of diabetes showed similar results (pooled rate ratio per 0.56 mmol/L increase in fasting blood glucose was 1.15, 95% confidence interval 1.05 to 1.27; P=0.003), strengthening the association between prediabetes and pancreatic cancer. Conclusions Every 0.56 mmol/L increase in fasting blood glucose is associated with a 14% increase in the rate of pancreatic cancer. As prediabetes can be improved or even reversed through lifestyle changes, early detection of prediabetes coupled with lifestyle changes could represent a viable strategy to curb the increasing incidence of pancreatic cancer. PMID

  1. Pentavalent vanadium at concentration of the underground water level enhances the sweet taste sense to glucose in college students.

    PubMed

    Nagai, Masanori; Saitoh, Junko; Ohno, Hiromi; Hitomi, Chiaki; Wada, Maki

    2006-02-01

    Underground water in volcanic areas contains vanadium when the basalt layer exists among igneous rocks. The concentration of vanadium in drinking water sometimes exceeds 0.8 microM in these areas, however, the physiological effects of vanadium, especially non-toxic effects, at concentrations lower than 1 microM are unknown. In the present experiments, we examined the effect of pentavalent vanadium and tetravalent vanadium at 0.8 and 8.0 microM concentrations on the recognition threshold to taste substances in healthy college students. Pentavalent vanadium, ammonium vanadate, lowered the sweet taste threshold to glucose at 0.8 and 8.0 microM as well. Tetravalent vanadium, vanadium sulfate, did not alter the threshold to glucose either at 8.0 microM or at 0.8 microM. Ammonium vanadate also decreased the sweet taste threshold to L-proline at 8.0 microM. Ammonium vanadate did not influence the sour taste threshold to hydrogen chloride. Neither ammonium sulfate nor ammonium bicarbonate altered the sweet taste threshold to glucose. Therefore, the effect of ammonium vanadate on the sweet taste threshold is attained by vanadium but not by ammonium. It was concluded that pentavalent vanadium at 0.8 microM intensifies the sweet taste sense to glucose rather specifically. We have first shown the physiological effect of vanadium at the concentration of the underground water level. PMID:16502326

  2. Effects of elevated atmospheric CO2 concentrations, clipping regimen and differential day/night atmospheric warming on tissue nitrogen concentrations of a perennial pasture grass

    PubMed Central

    Volder, Astrid; Gifford, Roger M.; Evans, John R.

    2015-01-01

    Forecasting the effects of climate change on nitrogen (N) cycling in pastures requires an understanding of changes in tissue N. We examined the effects of elevated atmospheric CO2 concentration, atmospheric warming and simulated grazing (clipping frequency) on aboveground and belowground tissue N concentrations and C : N ratios of a C3 pasture grass. Phalaris aquatica L. cv. ‘Holdfast’ was grown in the field in six transparent temperature gradient tunnels (18 × 1.5 × 1.5 m each), three at ambient atmospheric CO2 and three at 759 p.p.m. CO2. Within each tunnel, there were three air temperature treatments: ambient control, +2.2/+4.0 °C above ambient day/night warming and +3.0 °C continuous warming. A frequent and an infrequent clipping treatment were applied to each warming × CO2 combination. Green leaf N concentrations were decreased by elevated CO2 and increased by more frequent clipping. Both warming treatments increased leaf N concentrations under ambient CO2 concentrations, but did not significantly alter leaf N concentrations under elevated CO2 concentrations. Nitrogen resorption from leaves was decreased under elevated CO2 conditions as well as by more frequent clipping. Fine root N concentrations decreased strongly with increasing soil depth and were further decreased at the 10–60 cm soil depths by elevated CO2 concentrations. The interaction between the CO2 and warming treatments showed that leaf N concentration was affected in a non-additive manner. Changes in leaf C : N ratios were driven by changes in N concentration. Overall, the effects of CO2, warming and clipping treatments on aboveground tissue N concentrations were much greater than on belowground tissue. PMID:26272874

  3. Effects of elevated atmospheric CO2 concentrations, clipping regimen and differential day/night atmospheric warming on tissue nitrogen concentrations of a perennial pasture grass.

    PubMed

    Volder, Astrid; Gifford, Roger M; Evans, John R

    2015-01-01

    Forecasting the effects of climate change on nitrogen (N) cycling in pastures requires an understanding of changes in tissue N. We examined the effects of elevated atmospheric CO2 concentration, atmospheric warming and simulated grazing (clipping frequency) on aboveground and belowground tissue N concentrations and C : N ratios of a C3 pasture grass. Phalaris aquatica L. cv. 'Holdfast' was grown in the field in six transparent temperature gradient tunnels (18 × 1.5 × 1.5 m each), three at ambient atmospheric CO2 and three at 759 p.p.m. CO2. Within each tunnel, there were three air temperature treatments: ambient control, +2.2/+4.0 °C above ambient day/night warming and +3.0 °C continuous warming. A frequent and an infrequent clipping treatment were applied to each warming × CO2 combination. Green leaf N concentrations were decreased by elevated CO2 and increased by more frequent clipping. Both warming treatments increased leaf N concentrations under ambient CO2 concentrations, but did not significantly alter leaf N concentrations under elevated CO2 concentrations. Nitrogen resorption from leaves was decreased under elevated CO2 conditions as well as by more frequent clipping. Fine root N concentrations decreased strongly with increasing soil depth and were further decreased at the 10-60 cm soil depths by elevated CO2 concentrations. The interaction between the CO2 and warming treatments showed that leaf N concentration was affected in a non-additive manner. Changes in leaf C : N ratios were driven by changes in N concentration. Overall, the effects of CO2, warming and clipping treatments on aboveground tissue N concentrations were much greater than on belowground tissue. PMID:26272874

  4. Evaluation of Potential pH-Driven Metal Release Due to Elevated Groundwater CO2 Concentrations

    NASA Astrophysics Data System (ADS)

    Tinnacher, R. M.; Varadharajan, C.; Zheng, L.; Spycher, N.; Birkholzer, J. T.; Trautz, R. C.; Pugh, J. D.; Esposito, R.; Nico, P. S.

    2012-12-01

    The injection of carbon dioxide (CO2) emissions from industrial sources into deep geologic formations is a potential option for the control of CO2 concentrations in the atmosphere. While the risk of CO2 migration from the storage reservoir into potable groundwater is low considering the safeguards of site characterization and permitting, it is important to understand what type of potential impacts could occur and how to identify these impacts. Elevated CO2 concentrations may potentially lead to a decrease in groundwater pH and the subsequent release of metals and ions from natural sediments into the groundwater solution. In this risk scenario, potential metal release processes, such as enhanced mineral dissolution, metal desorption and/or ion exchange reactions, may be driven by changes in groundwater pH, the presence of carbonate ligands in solution or a combination of the two. However, a detailed understanding and a distinction of pH-driven and carbonate-driven metal release reactions are important for the development of site monitoring plans and remediation strategies, required by regulations in the unlikely event of a release. Hence, in this study we characterized metal release from natural sediments into synthetic groundwater solutions at two pH conditions in order to mimic the native groundwater pH (pH ~8.5) and the low pH conditions expected in the event of elevated CO2 concentrations (pH~5). In addition, results are compared between tests performed in the presence and absence of elevated CO2. Metal release was investigated in lab-scale sequential leaching experiments using two sediment types with different organic carbon contents over a time-frame of 25 days. Supernatant solutions were monitored for pH and characterized in terms of metal concentrations (ICP-MS), total inorganic carbon (TIC) and anion composition. Furthermore, experimental results were compared with data from a field study involving the controlled release of groundwater containing dissolved

  5. Ozone concentrations at a selected high-elevation forest site downwind Mexico City

    NASA Astrophysics Data System (ADS)

    Torres-JArdon, R.

    2013-05-01

    Torres-Jardón, R.*, Rosas-Pérez, I., Granada-Macías, L. M., Ruiz-Suárez, L. G. Centro de Ciencias de la Atmósfera, UNAM, México D. F. México * rtorres@unam.mx For many years, the vegetation of forest species such as Abies religiosa in natural parks located in the southwest mountains of Mexico City has attracted much attention since these parks have been experiencing a severe decline of unclear etiology. The high ozone levels in the area and the observed naked eye macroscopic, histological and cytological injuries on these species, strongly suggest an important contribution of tropospheric ozone to this deterioration process. Apart of historical short monitoring campaigns for measuring ozone levels in these mountains, it is known just a little is known about the present exposure levels at which the local vegetation is exposed. A continuous ozone analyzer has been in operation since 2011 at a high-elevation forest site (Parque Nacional Miguel Hidalgo, PNMH; 3110 m above mean sea level) located downwind of Mexico City Metropolitan Area (MCMA), in order to characterize the local ozone diel amplitude and its seasonal trend, as well as the influence of MCMA on the local O3 concentrations. Hourly average ozone data in PNMH shows that in general, the diel of ozone concentrations in the forest site has a statistical significant correlation with the pattern of ozone levels observed in several monitoring sites (smog receptor sites) within the MCMA, although the high elevation O3 levels are relatively lower than those in the urban area (around 2200 m above mean sea level). It is possible that a part of the oxidants in the air masses are removed by sink deposition processes during the air mass transport across the hills. The diel amplitude of ozone concentrations is small in the cold season, increasing as the seasons advance to June. As in the city, the highest ozone concentrations occur in April or May and the lowest levels during the rainy season, which extends from

  6. Intracranial subdural hematomas with elevated rivaroxaban concentration and subsequently detected spinal subdural hematoma: A case report.

    PubMed

    Yamaguchi, Yoshitaka; Koga, Masatoshi; Matsuki, Takayuki; Hino, Tenyu; Yokota, Chiaki; Toyoda, Kazunori

    2016-07-01

    A 79-year-old lean man with a height of 157cm and weight of 42kg (body mass index, 17.2kg/m(2)) receiving rivaroxaban developed an intracranial subdural hematoma and was treated conservatively. Because he had a reduced creatinine clearance of 44mL/min, his dosage of rivaroxaban was reduced from 15 to 10mg daily according to official Japanese prescribing information. However, he developed bilateral intracranial subdural hematomas 2weeks later. Plasma rivaroxaban concentration on anti-factor Xa chromogenic assay was elevated at 301ng/mL, suggesting excessive accumulation. He underwent burr hole drainage and resumed anticoagulation with warfarin. Subsequently, he developed a lumbosacral hematoma. He was treated conservatively and discharged without neurological sequelae. The main cause of the increased concentration of rivaroxaban was believed to be his older age and low body weight. The etiology of the spinal hematoma was suspected to be the migration of intracranial hematoma to the spinal subdural space. PMID:27240110

  7. Predicting the effects of elevated CO2 concentrations on catchment carbon and water fluxes

    NASA Astrophysics Data System (ADS)

    Donohue, R. J.; Roderick, M. L.; McVicar, T.; Farquhar, G. D.

    2014-12-01

    Anthropogenic activities are increasing atmospheric CO2 concentrations. Among the many observed and expected impacts of this on our climate and biosphere, one is the so-called CO2 fertilisation effect. In this effect the efficiency with which vegetation can acquire carbon relative to its water use increases proportionally with CO2 concentration, and this biological response has implications for both carbon and water balances. Despite considerable research into the impacts of CO2 fertilisation, there is still uncertainty on the catchment scale response of vegetation to elevated CO2. Here we present a simple, conceptually based, generic model for quantifying how CO2 fertilisation affects the structure, water use and productivity of vegetation. Using this new Carbon Use Efficiency (CUE) model we can account for Free Air Carbon Enrichment (FACE) experimental results from a diverse range of sites. We use the CUE model to estimate the effect of the ~18% rise in CO2 over the past three decades on the globe's vegetation cover, and transpiration and carbon assimilation rates.

  8. Physical and chemical changes in whey protein concentrate stored at elevated temperature and humidity.

    PubMed

    Tunick, Michael H; Thomas-Gahring, Audrey; Van Hekken, Diane L; Iandola, Susan K; Singh, Mukti; Qi, Phoebe X; Ukuku, Dike O; Mukhopadhyay, Sudarsan; Onwulata, Charles I; Tomasula, Peggy M

    2016-03-01

    In a case study, we monitored the physical properties of 2 batches of whey protein concentrate (WPC) under adverse storage conditions to provide information on shelf life in hot, humid areas. Whey protein concentrates with 34.9 g of protein/100g (WPC34) and 76.8 g of protein/100g (WPC80) were stored for up to 18 mo under ambient conditions and at elevated temperature and relative humidity. The samples became yellower with storage; those stored at 35 °C were removed from the study by 12 mo because of their unsatisfactory appearance. Decreases in lysine and increases in water activity, volatile compound formation, and powder caking values were observed in many specimens. Levels of aerobic mesophilic bacteria, coliforms, yeast, and mold were <3.85 log10 cfu/g in all samples. Relative humidity was not a factor in most samples. When stored in sealed bags, these samples of WPC34 and WPC80 had a shelf life of 9 mo at 35 °C but at least 18 mo at lower temperatures, which should extend the market for these products. PMID:26778305

  9. Elevated Endogenous Erythropoietin Concentrations Are Associated with Increased Risk of Brain Damage in Extremely Preterm Neonates

    PubMed Central

    Korzeniewski, Steven J.; Allred, Elizabeth; Logan, J. Wells; Fichorova, Raina N.; Engelke, Stephen; Kuban, Karl C. K.; O’Shea, T. Michael; Paneth, Nigel; Holm, Mari; Dammann, Olaf; Leviton, Alan

    2015-01-01

    Background We sought to determine, in very preterm infants, whether elevated perinatal erythropoietin (EPO) concentrations are associated with increased risks of indicators of brain damage, and whether this risk differs by the co-occurrence or absence of intermittent or sustained systemic inflammation (ISSI). Methods Protein concentrations were measured in blood collected from 786 infants born before the 28th week of gestation. EPO was measured on postnatal day 14, and 25 inflammation-related proteins were measured weekly during the first 2 postnatal weeks. We defined ISSI as a concentration in the top quartile of each of 25 inflammation-related proteins on two separate days a week apart. Hypererythropoietinemia (hyperEPO) was defined as the highest quartile for gestational age on postnatal day 14. Using logistic regression and multinomial logistic regression models, we compared risks of brain damage among neonates with hyperEPO only, ISSI only, and hyperEPO+ISSI, to those who had neither hyperEPO nor ISSI, adjusting for gestational age. Results Newborns with hyperEPO, regardless of ISSI, were more than twice as likely as those without to have very low (< 55) Mental (OR 2.3; 95% CI 1.5-3.5) and/or Psychomotor (OR 2.4; 95% CI 1.6-3.7) Development Indices (MDI, PDI), and microcephaly at age two years (OR 2.4; 95%CI 1.5-3.8). Newborns with both hyperEPO and ISSI had significantly increased risks of ventriculomegaly, hemiparetic cerebral palsy, microcephaly, and MDI and PDI < 55 (ORs ranged from 2.2-6.3), but not hypoechoic lesions or other forms of cerebral palsy, relative to newborns with neither hyperEPO nor ISSI. Conclusion hyperEPO, regardless of ISSI, is associated with elevated risks of very low MDI and PDI, and microcephaly, but not with any form of cerebral palsy. Children with both hyperEPO and ISSI are at higher risk than others of very low MDI and PDI, ventriculomegaly, hemiparetic cerebral palsy, and microcephaly. PMID:25793991

  10. Factors controlling elevated lead concentrations in water samples from aquifer systems in Florida

    USGS Publications Warehouse

    Katz, B.G.; Bullen, M.P.; Bullen, T.D.; Hansard, Paul

    1999-01-01

    Concentrations of total lead (Pb) and dissolved Pb exceeded the U.S. Environmental Protection Agency action level of 15 micrograms per liter (mg/L) in approximately 19 percent and 1.3 percent, respectively, of ground-water samples collected during 1991-96 from a statewide network of monitoring wells designed to delineate background water quality of Florida's major aquifer systems. Differences in total Pb concentrations among aquifer systems reflect the combined influence of anthropogenic sources and chemical conditions in each system. A highly significant (p<0.001) difference in median total Pb concentrations was found for water samples from wells with water-level recording devices that contain Pb-counterweights (14 mg/L) compared to non-recorder wells (2 mg/L). Differences between total Pb concentrations for recorder and non-recorder wells are even more pronounced when compared for each aquifer system. The largest differences for recorder status are found for the surficial aquifer system, where median total Pb concentrations are 44 and 2.4 mg/L for recorder wells and non-recorder wells, respectively. Leaching of Pb from metal casing materials is another potential source of Pb in ground water samples. Median total Pb concentrations in water samples from the surficial, intermediate, and Floridan aquifer systems are higher from recorder wells cased with black iron than for recorder wells with steel and PVC casing material. Stable isotopes of Pb were used in this study to distinguish between anthropogenic and natural sources of Pb in ground water, as Pb retains the isotopic signature of the source from which it is derived. Based on similarities between slopes and intercepts of trend lines for various sample types (plots of 206Pb/204Pb versus 208Pb/204Pb and 207Pb/204Pb versus 208Pb/204Pb) the predominant source of total Pb in water samples from the surficial aquifer system is corrosion of Pb counterweights. It is likely that only ground-water samples, not the aquifer

  11. Effect of Elevated CO2 Concentration, Elevated Temperature and No Nitrogen Fertilization on Methanogenic Archaeal and Methane-Oxidizing Bacterial Community Structures in Paddy Soil

    PubMed Central

    Liu, Dongyan; Tago, Kanako; Hayatsu, Masahito; Tokida, Takeshi; Sakai, Hidemitsu; Nakamura, Hirofumi; Usui, Yasuhiro; Hasegawa, Toshihiro; Asakawa, Susumu

    2016-01-01

    Elevated concentrations of atmospheric CO2 ([CO2]) enhance the production and emission of methane in paddy fields. In the present study, the effects of elevated [CO2], elevated temperature (ET), and no nitrogen fertilization (LN) on methanogenic archaeal and methane-oxidizing bacterial community structures in a free-air CO2 enrichment (FACE) experimental paddy field were investigated by PCR-DGGE and real-time quantitative PCR. Soil samples were collected from the upper and lower soil layers at the rice panicle initiation (PI) and mid-ripening (MR) stages. The composition of the methanogenic archaeal community in the upper and lower soil layers was not markedly affected by the elevated [CO2], ET, or LN condition. The abundance of the methanogenic archaeal community in the upper and lower soil layers was also not affected by elevated [CO2] or ET, but was significantly increased at the rice PI stage and significantly decreased by LN in the lower soil layer. In contrast, the composition of the methane-oxidizing bacterial community was affected by rice-growing stages in the upper soil layer. The abundance of methane-oxidizing bacteria was significantly decreased by elevated [CO2] and LN in both soil layers at the rice MR stage and by ET in the upper soil layer. The ratio of mcrA/pmoA genes correlated with methane emission from ambient and FACE paddy plots at the PI stage. These results indicate that the decrease observed in the abundance of methane-oxidizing bacteria was related to increased methane emission from the paddy field under the elevated [CO2], ET, and LN conditions. PMID:27600710

  12. Preliminary evaluation of optical glucose sensing in red cell concentrations using near-infrared diffuse-reflectance spectroscopy.

    PubMed

    Suzuki, Yusuke; Maruo, Katsuhiko; Zhang, Alice W; Shimogaki, Kazushige; Ogawa, Hideto; Hirayama, Fumiya

    2012-01-01

    Bacterial contamination of blood products is one of the most frequent infectious complications of transfusion. Since glucose levels in blood supplies decrease as bacteria proliferate, it should be possible to detect the presence of bacterial contamination by measuring the glucose concentrations in the blood components. Hence this study is aimed to serve as a preliminary study for the nondestructive measurement of glucose level in transfusion blood. The glucose concentrations in red blood cell (RBC) samples were predicted using near-infrared diffuse-reflectance spectroscopy in the 1350 to 1850 nm wavelength region. Furthermore, the effects of donor, hematocrit level, and temperature variations among the RBC samples were observed. Results showed that the prediction performance of a dataset which contained samples that differed in all three parameters had a standard error of 29.3 mg/dL. Multiplicative scatter correction (MSC) preprocessing method was also found to be effective in minimizing the variations in scattering patterns created by various sample properties. The results suggest that the diffuse-reflectance spectroscopy may provide another avenue for the detection of bacterial contamination in red cell concentrations (RCC) products. PMID:22352670

  13. Preliminary evaluation of optical glucose sensing in red cell concentrations using near-infrared diffuse-reflectance spectroscopy

    NASA Astrophysics Data System (ADS)

    Suzuki, Yusuke; Maruo, Katsuhiko; Zhang, Alice W.; Shimogaki, Kazushige; Ogawa, Hideto; Hirayama, Fumiya

    2012-01-01

    Bacterial contamination of blood products is one of the most frequent infectious complications of transfusion. Since glucose levels in blood supplies decrease as bacteria proliferate, it should be possible to detect the presence of bacterial contamination by measuring the glucose concentrations in the blood components. Hence this study is aimed to serve as a preliminary study for the nondestructive measurement of glucose level in transfusion blood. The glucose concentrations in red blood cell (RBC) samples were predicted using near-infrared diffuse-reflectance spectroscopy in the 1350 to 1850 nm wavelength region. Furthermore, the effects of donor, hematocrit level, and temperature variations among the RBC samples were observed. Results showed that the prediction performance of a dataset which contained samples that differed in all three parameters had a standard error of 29.3 mg/dL. Multiplicative scatter correction (MSC) preprocessing method was also found to be effective in minimizing the variations in scattering patterns created by various sample properties. The results suggest that the diffuse-reflectance spectroscopy may provide another avenue for the detection of bacterial contamination in red cell concentrations (RCC) products.

  14. Observations of the uptake of carbonyl sulfide (COS) by trees under elevated atmospheric carbon dioxide concentrations

    NASA Astrophysics Data System (ADS)

    Sandoval-Soto, L.; Kesselmeier, M.; Schmitt, V.; Wild, A.; Kesselmeier, J.

    2012-08-01

    Global change forces ecosystems to adapt to elevated atmospheric concentrations of carbon dioxide (CO2). We understand that carbonyl sulfide (COS), a trace gas which is involved in building up the stratospheric sulfate aerosol layer, is taken up by vegetation with the same triad of the enzymes which are metabolizing CO2, i.e. ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), phosphoenolpyruvate carboxylase (PEP-Co) and carbonic anhydrase (CA). Therefore, we discuss a physiological/biochemical acclimation of these enzymes affecting the sink strength of vegetation for COS. We investigated the acclimation of two European tree species, Fagus sylvatica and Quercus ilex, grown inside chambers under elevated CO2, and determined the exchange characteristics and the content of CA after a 1-2 yr period of acclimation from 350 ppm to 800 ppm CO2. We demonstrate that a compensation point, by definition, does not exist. Instead, we propose to discuss a point of uptake affinity (PUA). The results indicate that such a PUA, the CA activity and the deposition velocities may change and may cause a decrease of the COS uptake by plant ecosystems, at least as long as the enzyme acclimation to CO2 is not surpassed by an increase of atmospheric COS. As a consequence, the atmospheric COS level may rise causing an increase of the radiative forcing in the troposphere. However, this increase is counterbalanced by the stronger input of this trace gas into the stratosphere causing a stronger energy reflection by the stratospheric sulfur aerosol into space (Brühl et al., 2012). These data are very preliminary but may trigger a discussion on COS uptake acclimation to foster measurements with modern analytical instruments.

  15. Elevated CO2 and warming differentially impact carbon isotope discrimination and tissue N concentration in five grassland species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We measured carbon isotope discrimination ('13C) and tissue N concentration in above ground biomass over four years at the Prairie Heating and CO2 Enrichment (PHACE) experiment in southeastern Wyoming, USA. This factorial experiment combined FACE (ambient and elevated [600 ppm] CO2 concentration), e...

  16. Ultra-acute increase in blood glucose during prehospital phase is associated with worse short-term and long-term survival in ST-elevation myocardial infarction

    PubMed Central

    2014-01-01

    Background The current study was to investigate the blood glucose changes in ultra-acute phase in patients with ST-elevation myocardial infarction (STEMI) and its associations with patient outcome. Methods This study was a retrospective population-based observational study utilizing prospectively collected registry data complemented with laboratory data. All adult patients with STEMI treated by emergency medical services (EMS) in the city of Helsinki from January 2006 to December 2010 were included in the study. Both prehospital and hospital admission glucose values were available from 152 (32%) of all STEMI patients (n = 469). Results Change in blood glucose from prehospital phase to emergency department admission was significantly higher in non-survivors within 30 days compared to survivors (+1.2 ± 5.1 vs. -0.3 ± 2.4 mmol/l [mean ± SD], P = 0.03). Furthermore, the 3-year survival rate was significantly lower in patients with an evident (≥2 mmol/l) rise in blood glucose (P = 0.02). In patients with impaired left ventricle function (best ejection fraction < 40%), blood glucose increased more compared to patients without it (1.2 ± 2.9 vs. 0.4 ± 2.7 mmol/l, P = 0.01). Increase in glucose was correlated with peak myocardial creatinine kinase (r = 0.17, P = 0.04) as a marker of increased size of infarct, but not with glycosylated haemoglobin A1C as a marker of chronic hyperglycaemia (r = −0.12, P = 0.27). Conclusions In patients with STEMI, ultra-acute hyperglycaemia during prehospital phase is associated with increased mortality, impaired cardiac function and increased size of infarct. PMID:24886984

  17. Stability assessment of o/w parenteral nutrition emulsions in the presence of high glucose and calcium concentrations.

    PubMed

    Télessy, I G; Balogh, J; Turmezei, J; Dredán, J; Zelkó, R

    2011-09-10

    The purpose of the present study was to examine how the colloid stability features of o/w parenteral nutrition emulsions made with SMOFlipid (lipid emulsion based on soybean oil, medium chain triglycerides, olive oil and fish oil) will change in the presence of high concentration of calcium and glucose if usual micronutrients are also present, according to the needs of the clinical nutrition patient. Particle size analysis, zeta potential, dynamic surface tension measurements and light microscopic screening were carried out to evaluate the possible changes in the kinetic stability of the emulsions. Our results indicate that the higher glucose concentration of 15 or 20% could not compensate the emulsion-destabilizing effect of higher (5 mM) calcium concentration even in the presence of a modern fat emulsion. Therefore calcium demand of undernourished patient requiring 5 mM or higher final Ca²⁺ content in nutrient solution should be supplemented in another way. PMID:21636233

  18. The Effect of Serum 25-Hydroxyvitamin D on Elevated Homocysteine Concentrations in Participants of a Preventive Health Program

    PubMed Central

    Pham, Truong-Minh; Ekwaru, John Paul; Mastroeni, Silmara S.; Mastroeni, Marco F.; Loehr, Sarah A.; Veugelers, Paul J.

    2016-01-01

    Both lower serum 25-hydroxyvitamin D [25(OH)D] and elevated homocysteine concentrations are potential risk factors for cardiovascular disease (CVD). A recent analysis of the National Health and Nutrition Examination Survey reported an inverse association of serum 25(OH)D with homocysteine, however, the longitudinal relationship has yet to be investigated. We hypothesized and examined whether a temporal increase in 25(OH)D concentrations is paralleled by a reduction in the risk for elevated homocysteine. We analyzed data of 4475 participants with repeated assessments of serum 25(OH)D and homocysteine concentrations who enrolled in a preventive health program that encourages vitamin D supplementation and monitors serum 25(OH)D and homocysteine concentrations. We defined elevated homocysteine as concentrations greater than 13 micromoles per liter. Logistic regression was applied to assess the association of temporal changes in serum 25(OH)D with the risk of elevated homocysteine. We observed an inverse gradient whereby greater increases in 25(OH)D concentrations were associated with a lower prevalence of elevated homocysteine. Relative to those without temporal increases in 25(OH)D, participants who showed improvements in their serum 25(OH)D concentrations of “<25”, “25–50”, “50–75”, and “≥75” nanomoles per liter at follow up were 0.92 (95% confidence interval: 0.62–1.37), 0.52 (0.33–0.80), 0.34 (0.20–0.58), and 0.32 (0.19–0.54) times as likely to have elevated homocysteine, respectively. These observations suggest that temporal improvements in vitamin D status reduce serum homocysteine concentrations, and therefore may potentially contribute to the primary prevention of CVD. PMID:27548258

  19. The Effect of Serum 25-Hydroxyvitamin D on Elevated Homocysteine Concentrations in Participants of a Preventive Health Program.

    PubMed

    Pham, Truong-Minh; Ekwaru, John Paul; Mastroeni, Silmara S; Mastroeni, Marco F; Loehr, Sarah A; Veugelers, Paul J

    2016-01-01

    Both lower serum 25-hydroxyvitamin D [25(OH)D] and elevated homocysteine concentrations are potential risk factors for cardiovascular disease (CVD). A recent analysis of the National Health and Nutrition Examination Survey reported an inverse association of serum 25(OH)D with homocysteine, however, the longitudinal relationship has yet to be investigated. We hypothesized and examined whether a temporal increase in 25(OH)D concentrations is paralleled by a reduction in the risk for elevated homocysteine. We analyzed data of 4475 participants with repeated assessments of serum 25(OH)D and homocysteine concentrations who enrolled in a preventive health program that encourages vitamin D supplementation and monitors serum 25(OH)D and homocysteine concentrations. We defined elevated homocysteine as concentrations greater than 13 micromoles per liter. Logistic regression was applied to assess the association of temporal changes in serum 25(OH)D with the risk of elevated homocysteine. We observed an inverse gradient whereby greater increases in 25(OH)D concentrations were associated with a lower prevalence of elevated homocysteine. Relative to those without temporal increases in 25(OH)D, participants who showed improvements in their serum 25(OH)D concentrations of "<25", "25-50", "50-75", and "≥75" nanomoles per liter at follow up were 0.92 (95% confidence interval: 0.62-1.37), 0.52 (0.33-0.80), 0.34 (0.20-0.58), and 0.32 (0.19-0.54) times as likely to have elevated homocysteine, respectively. These observations suggest that temporal improvements in vitamin D status reduce serum homocysteine concentrations, and therefore may potentially contribute to the primary prevention of CVD. PMID:27548258

  20. Application of time-resolved glucose concentration photoacoustic signals based on an improved wavelet denoising

    NASA Astrophysics Data System (ADS)

    Ren, Zhong; Liu, Guodong; Huang, Zhen

    2014-10-01

    Real-time monitoring of blood glucose concentration (BGC) is a great important procedure in controlling diabetes mellitus and preventing the complication for diabetic patients. Noninvasive measurement of BGC has already become a research hotspot because it can overcome the physical and psychological harm. Photoacoustic spectroscopy is a well-established, hybrid and alternative technique used to determine the BGC. According to the theory of photoacoustic technique, the blood is irradiated by plused laser with nano-second repeation time and micro-joule power, the photoacoustic singals contained the information of BGC are generated due to the thermal-elastic mechanism, then the BGC level can be interpreted from photoacoustic signal via the data analysis. But in practice, the time-resolved photoacoustic signals of BGC are polluted by the varities of noises, e.g., the interference of background sounds and multi-component of blood. The quality of photoacoustic signal of BGC directly impacts the precision of BGC measurement. So, an improved wavelet denoising method was proposed to eliminate the noises contained in BGC photoacoustic signals. To overcome the shortcoming of traditional wavelet threshold denoising, an improved dual-threshold wavelet function was proposed in this paper. Simulation experimental results illustrated that the denoising result of this improved wavelet method was better than that of traditional soft and hard threshold function. To varify the feasibility of this improved function, the actual photoacoustic BGC signals were test, the test reslut demonstrated that the signal-to-noises ratio(SNR) of the improved function increases about 40-80%, and its root-mean-square error (RMSE) decreases about 38.7-52.8%.

  1. Serum progranulin concentrations are not responsive during oral lipid tolerance test and oral glucose tolerance test.

    PubMed

    Schmid, A; Leszczak, S; Ober, I; Schäffler, A; Karrasch, T

    2015-07-01

    The postprandial regulation of progranulin by oral uptake of lipids and carbohydrates in healthy individuals has not yet been investigated. The regulation of progranulin in 2 large cohorts of healthy volunteers during oral lipid tolerance test (OLTT; n=100) and oral glucose tolerance test (OGTT; n=100) was analyzed. One hundred healthy volunteers underwent OLTT and OGTT in an outpatient setting. Venous blood was drawn at 0 hours (h) (fasting) and at 2, 4, and 6 h in OLTT or 1 and 2 h in OGTT. A novel OLTT solution completely free of carbohydrates and protein was applied. Subjects were characterized by anthropometric and laboratory parameters. Serum concentrations of progranulin were measured by enzyme-linked immunosorbent assay (ELISA). Circulating progranulin levels remained unchanged during OLTT and OGTT. Fasting progranulin levels ranged between 31.3±8.7 and 40.6±7.7 ng/ml and were not different in subgroups addressing BMI, gender, family history, smoking habits, and hormonal contraception. There was a reciprocal correlation of progranulin with HDL (negative) and LDL cholesterol levels (positive). In healthy adults, fasting and postprandial circulating progranulin levels are not different in BMI subgroups. Oral uptake of carbohydrates and lipids does not influence circulating progranulin levels in a short-term manner. A postprandial and short-term regulation of this adipokine is absent, at least in healthy subjects. There is a negative correlation of progranulin with HDL cholesterol, but a positive correlation with LDL cholesterol. This reciprocal association might be of physiological importance for an individual's atherosclerotic risk. PMID:25565096

  2. High-cell-density batch fermentation of Rhodococcus opacus PD630 using a high glucose concentration for triacylglycerol production.

    PubMed

    Kurosawa, Kazuhiko; Boccazzi, Paolo; de Almeida, Naomi M; Sinskey, Anthony J

    2010-06-01

    Biodiesel, monoalkyl esters of long-chain fatty acids with short-chain alcohols derived from triacylglycerols (TAGs), can be produced from renewable biomass sources. Recently, there has been interest in producing microbial oils from oleaginous microorganisms. Rhodococcus opacus PD630 is known to accumulate large amounts of TAGs. Following on these earlier works we demonstrate that R. opacus PD630 has the uncommon capacity to grow in defined media supplemented with glucose at a concentration of 300 g l(-1) during batch-culture fermentations. We found that we could significantly increase concentrations of both glucose and (NH4)2SO4 in the production medium resulting in a dramatic increase in fatty acid production when pH was controlled. We describe the experimental design protocol used to achieve the culture conditions necessary to obtain both high-cell-density and TAG accumulation; specifically, we describe the importance of the C/N ratio of the medium composition. Our bioprocess results demonstrate that R. opacus PD630 grown in batch-culture with an optimal production medium containing 240 g l(-1) glucose and 13.45 g l(-1) (NH4)2SO4 (C/N of 17.8) yields 77.6 g l(-1) of cell dry weight composed of approximately 38% TAGs indicating that this strain holds great potential as a future source of industrial biodiesel on starchy cellulosic feedstocks that are glucose polymers. PMID:20412824

  3. Dynamics of glucose and insulin concentration connected to the β‐cell cycle: model development and analysis

    PubMed Central

    2012-01-01

    Background Diabetes mellitus is a group of metabolic diseases with increased blood glucose concentration as the main symptom. This can be caused by a relative or a total lack of insulin which is produced by the β‐cells in the pancreatic islets of Langerhans. Recent experimental results indicate the relevance of the β‐cell cycle for the development of diabetes mellitus. Methods This paper introduces a mathematical model that connects the dynamics of glucose and insulin concentration with the β‐cell cycle. The interplay of glucose, insulin, and β‐cell cycle is described with a system of ordinary differential equations. The model and its development will be presented as well as its mathematical analysis. The latter investigates the steady states of the model and their stability. Results Our model shows the connection of glucose and insulin concentrations to the β‐cell cycle. In this way the important role of glucose as regulator of the cell cycle and the capability of the β‐cell mass to adapt to metabolic demands can be presented. Simulations of the model correspond to the qualitative behavior of the glucose‐insulin regulatory system showed in biological experiments. Conclusions This work focusses on modeling the physiological situation of the glucose‐insulin regulatory system with a detailed consideration of the β‐cell cycle. Furthermore, the presented model allows the simulation of pathological scenarios. Modification of different parameters results in simulation of either type 1 or type 2 diabetes. PMID:23164557

  4. Toxic effects of mildly elevated homocysteine concentrations in neuronal-like cells.

    PubMed

    Currò, M; Gugliandolo, A; Gangemi, C; Risitano, R; Ientile, R; Caccamo, D

    2014-08-01

    Epidemiological and experimental evidence indicated that hyperhomocysteinemia is associated with neurodegeneration. However, homocysteine neurotoxic effects have been so far investigated mostly by employing homocysteine concentrations (≥100 µM) much higher than homocysteine mean plasma levels (20 µM) observed in patients with neurodegenerative disorders. While evaluating the effects of a prolonged exposure to ~20 µM homocysteine in neuronal-like differentiated SH-SY5Y cells, we observed a 35% loss of cell viability and a four-fold increase in reactive oxygen species levels in cells incubated with homocysteine for five days compared with controls. Moreover, homocysteine increased by 30% and around two-fold, respectively, the Comet-positive cell number and DNA damage indexes (tail length, T-DNA, olive tail moment) compared with controls. Cell response to homocysteine-induced DNA damage involved the up-regulation of Bax and, at a greater extent, Bcl-2, but not caspase-3, in association with a p53-independent increase of p21 levels; concomitantly, also p16 levels were increased. When looking at time-dependent changes in cyclin expression, we found that a significant up-regulation of cyclins D1, A1, E1, but not B1, concomitant with p21 down-regulation, occurred in cells incubated with homocysteine for three days. However, in line with the observed increase of p21 and p16 levels, a five days incubation with homocysteine induced cyclin down-regulation accompanied by a strong reduction of phosphorylated pRB amounts. These results suggest that, when prolonged, the exposure of neuronal-like cells to mildly elevated homocysteine concentrations triggers oxidative and genotoxic stress involving an early induction of cyclins, that is late repressed by G1-S check-point regulators. PMID:24867323

  5. Arsenic concentrations, related environmental factors, and the predicted probability of elevated arsenic in groundwater in Pennsylvania

    USGS Publications Warehouse

    Gross, Eliza L.; Low, Dennis J.

    2013-01-01

    Logistic regression models were created to predict and map the probability of elevated arsenic concentrations in groundwater statewide in Pennsylvania and in three intrastate regions to further improve predictions for those three regions (glacial aquifer system, Gettysburg Basin, Newark Basin). Although the Pennsylvania and regional predictive models retained some different variables, they have common characteristics that can be grouped by (1) geologic and soils variables describing arsenic sources and mobilizers, (2) geochemical variables describing the geochemical environment of the groundwater, and (3) locally specific variables that are unique to each of the three regions studied and not applicable to statewide analysis. Maps of Pennsylvania and the three intrastate regions were produced that illustrate that areas most at risk are those with geology and soils capable of functioning as an arsenic source or mobilizer and geochemical groundwater conditions able to facilitate redox reactions. The models have limitations because they may not characterize areas that have localized controls on arsenic mobility. The probability maps associated with this report are intended for regional-scale use and may not be accurate for use at the field scale or when considering individual wells.

  6. Changes in glucose fermentation pathways by an enriched bacterial culture in response to regulated dissolved H2 concentrations.

    PubMed

    Zheng, Hang; Zeng, Raymond J; Duke, Mikel C; O'Sullivan, Cathryn A; Clarke, William P

    2015-06-01

    It is well established that metabolic pathways in the fermentation of organic waste are primarily controlled by dissolved H2 concentrations, but there is no reported study that compares observed and predicted shifts in fermentation pathways induced by manipulating the dissolved H2 concentration. A perfusion system is presented that was developed to control dissolved H2 concentrations in the continuous fermentation of glucose by a culture highly enriched towards Thermoanaerobacterium thermosaccharolyticum (86 ± 9% relative abundance) from an originally diverse consortia in the leachate of a laboratory digester fed with municipal solid waste. Media from a 2.5 L CSTR was drawn through sintered steel membrane filters to retain biomass, allowing vigorous sparging in a separate chamber without cellular disruption. Through a combination of sparging and variations in glucose feeding rate from 0.8 to 0.2 g/L/d, a range of steady state fermentations were performed with dissolved H2 concentrations as low as an equivalent equilibrated H2 partial pressure of 3 kPa. Trends in product formation rates were simulated using a H2 regulation partitioning model. The model correctly predicted the direction of products redistribution in response to H2 concentration changes and the acetate and butyrate formation rates when H2 concentrations were less than 6 kPa. However, the model over-estimated acetate, ethanol and butanol productions at the expense of butyrate production at higher H2 concentrations. The H2 yield at the lowest dissolved H2 concentration was 2.67 ± 0.08 mol H2 /mol glucose, over 300% higher than the yield achieved in a CSTR operated without sparging. PMID:25545692

  7. Relationships between serum asunaprevir concentration and alanine aminotransferase elevation during daclatasvir plus asunaprevir for chronic HCV genotype 1b infection.

    PubMed

    Akuta, Norio; Sezaki, Hitomi; Suzuki, Fumitaka; Kawamura, Yusuke; Hosaka, Tetsuya; Kobayashi, Masahiro; Kobayashi, Mariko; Saitoh, Satoshi; Suzuki, Yoshiyuki; Arase, Yasuji; Ikeda, Kenji; Kumada, Hiromitsu

    2016-03-01

    Alanine aminotransferase (ALT) elevations were the most frequent adverse events during all-oral combinations with daclatasvir and asunaprevir for patients with hepatitis C virus (HCV) infection, but the underline mechanisms are unclear. Seventy patients with chronic HCV genotype 1b infection, who were introduced daclatasvir 60 mg once daily plus asunaprevir 100 mg twice daily for 24 weeks, were measured serum asunaprevir concentrations at the one point or more of 2, 4, and 8 weeks after the start of treatment. In 4 and 8 weeks after the start of treatment, asunaprevir concentrations in patients with albumin levels <3.6 g/dl at baseline were significantly higher than those in patients with albumin levels ≥3.6 g/dl. The baseline factors did not affect to ALT severe elevations (≥300 IU/l). At 2 weeks after the start of treatment, ALT severe elevations with asunaprevir concentrations of ≥800 ng/ml (54.5%) tended to indicate the higher rates than those of <800 ng/ml (17.6%). Furthermore, the discontinuation or reduction of asunaprevir improved ALT levels, regardless the significant decrease of serum asunaprevir concentrations. In conclusion, serum albumin levels affected to serum asunaprevir concentrations, and serum asunaprevir concentrations might partly affect to ALT severe elevations. Further large-scale prospective studies are needed to investigate the impact of the discontinuation or reduction of asunaprevir to help in the design of more effective therapeutic regimens. PMID:26292191

  8. Reduced oocyte and embryo quality in response to elevated non-esterified fatty acid concentrations: a possible pathway to subfertility?

    PubMed

    Van Hoeck, Veerle; Bols, Peter E J; Binelli, Mario; Leroy, Jo L M R

    2014-09-01

    Reproductive performance is increasingly considered as a 'barometer' of general well-being of the mother. A normal maternal 'metabolic health' status is essential to safeguard successful ovulation, conception and further embryo development. When alterations in serum metabolites are reflected in the oocyte and embryonic micro-environment, these metabolic changes can affect follicle health, oocyte development and even subsequent embryo physiology. The search continues for signals that may be critically affecting the early developmental stages in life. Years of expertise in animal in vitro embryo culture models contribute to the awareness on the influence of elevated non-esterified fatty acid (NEFA) concentrations on follicle cells, oocyte and embryo quality. High NEFA concentrations in the blood are known to alter the follicular micro-environment. The latter alterations in NEFA concentrations have been associated with a disappointing fertility outcome through disabled ovarian cell function and reduced oocyte's developmental competence. Even more, elevated NEFA concentrations during bovine oocyte maturation influence the subsequent embryo characteristics. This review provides a cross-species overview on the consequences of elevated NEFA concentrations, originating from maternal lipolytic conditions, on female fertility, with particular focus on the early stages in life. Thereby, we will describe to what extent elevated serum NEFA concentrations are a potential threat around the period of conception. PMID:25129636

  9. Dissolved sulfide in groundwater with elevated arsenic concentrations at Winthrop, Maine

    NASA Astrophysics Data System (ADS)

    He, Y.; Zheng, Y.; Zheng, Y.; Locke, D. C.; Simpson, J. H.; Stute, M.

    2001-12-01

    Although sulfur is a biogeochemically significant element because of its strong influence on and response to redox conditions, there are relatively few reliable data sets of trace levels of dissolved sulfide \\(less than1 uM \\) in groundwaters This circumstance results from the relatively high detection limit \\(˜ 1uM \\) of methylene blue colorimetry and the general lack of sensitive methods for field analysis. We were motivated to investigate trace levels of dissolved sulfide because highly insoluble sulfide precipitates of many elements such as As and Fe represent important removal pathways for these metals in reducing groundwaters. Using differential pulse cathodic stripping voltammetry \\(DPCSV\\) capable of detecting 4 nM of dissolved sulfide, we observed that at a site in Winthrop, Maine, groundwater sulfide concentrations ranged from less than 4 nM to ˜ 2000 nM for about a dozen multi-level observation wells under a landfill cap and less than 4 nM to ˜ 7300 nM from several nearby monitoring wells outside the landfill. Sulfide concentrations generally increased when oxygen reduction potential \\(ORP\\) values became more negative. Determination of sulfide should be carried out within 1 hr of sample collection. Samples taken by two methods, \\(1\\) PTFE syringes with luer-lock valves and \\(2\\) BOD bottles show a rapid decline of sulfide following sampling, with up to 90% and 60% losses, respectively, after 24 hrs of storage at 4 ° C. Despite the three orders of magnitude range of dissolved sulfide, arsenic and iron concentrations were all elevated in observational wells installed in a roughly 25 m by 20 m rectangle under the landfill cap, suggesting that As remains mobile under mildly sulfate-reducing conditions. In one well outside of the landfill area, with extremely negative ORP \\(-321 mV\\) and ˜ 7300 nM of dissolved sulfide, groundwater was very low in dissolved As, Fe, and sulfate, suggesting that precipitation of arsenopyrite could be a

  10. Effect of glucose concentration in a model light-scattering suspension on propagation of ultrashort laser pulses

    SciTech Connect

    Popov, A P; Priezzhev, A V; Myllylae, Risto

    2005-11-30

    The propagation of laser pulses in the 2% aqueous solution of intralipid - a suspension of lipid particles with optical properties close to those of the human skin, is numerically simulated at different glucose concentrations. The temporal profiles of 820-nm laser pulses diffusely backscattered from a flat, 2-mm thick solution layer are simulated. The laser pulse profiles are detected by fibreoptic detectors of diameter 0.3 mm with the numerical apertures 0.19, 0.29, and 0.39. It is shown that this method can be used to detect changes in the glucose level in the physiological concentration range (100-500 mg dL{sup -1}) by monitoring variations in the peak intensity and area of the laser pulse temporal profile (pulse energy). (laser applications in medicine)

  11. Will Elevated Carbon Dioxide Concentration Amplify the Benefits of Nitrogen Fixation in Legumes?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Current evidence suggests there are three key features of the response of legumes to elevated [CO2]: (1) unlike other non-leguminous C3 plants, only legumes have the potential to maximize the benefit of elevated [CO2] by matching stimulated photosynthesis with increased N2 fixation; (2) this potenti...

  12. Acclimation of Nitrogen Uptake Capacity of Rice to Elevated Atmospheric CO2 Concentration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nitrogen is one of the major variables affecting the response of crop yields to elevated carbon dioxide. Elevated carbon dioxide increases root size, but there are no consistent reports of carbon dioxide effects on nitrogen uptake rates per unit of root. We proposed a simple concept for analysing ...

  13. Waveguide-type localized plasmon resonance biosensor for noninvasive glucose concentration detection

    NASA Astrophysics Data System (ADS)

    Nashchekin, A. V.; Nevedomskiy, V. N.; Obraztsov, P. A.; Stepanenko, O. V.; Sidorov, A. I.; Usov, O. A.; Turoverov, K. K.; Konnikov, S. G.

    2012-06-01

    The waveguide type biosensors for noninvasive glucose detection based on LSPR of silver nanoparticles were fabricated by thermal diffusion in UV-irradiated photo-thermo-refractive (PTR) glasses and by ion-exchange method in sodiumborosilicate glasses in water vapor atmosphere. The optical and structural properties of the obtained nanocomposites were investigated. The D-glucose/D-galactose binding protein (GGBP) was chosen as a sensitive element of biosensor and successable immobilized on top of PTR glass. The change in absorption spectra were judged due to the presence of GGBP on the substrate surface.

  14. Effects of elevated atmospheric CO2 concentration on the nutrient uptake characteristics of Japanese larch (Larix kaempferi).

    PubMed

    Shinano, Takuro; Yamamoto, Takuya; Tawaraya, Keitaro; Tadokoro, Masaru; Koike, Takayoshi; Osaki, Mitsuru

    2007-01-01

    We evaluated the response of Japanese larch (Larix kaempferi Sieb. & Zucc.) to elevated atmospheric CO(2) concentration ([CO(2)]) (689 +/- 75 ppm in 2002 and 697 +/- 90 ppm in 2003) over 2 years in a field experiment with open-top chambers. Root activity was assessed as nitrogen, phosphorus and potassium uptake rates estimated from successive measurements of absorbed amounts. Dry matter production of whole plants was unaffected by elevated [CO(2)] in the first year of treatment, but increased significantly in response to elevated [CO(2)] in the second year. In contrast, elevated [CO(2)] increased the root to shoot ratio and fine root dry mass in the first year, but not in the second year. Elevated [CO(2)] had no effect on tissue N, P and K concentrations. Uptake rates of N, P and K correlated with whole-plant relative growth rates, but were unaffected by growth [CO(2)], as was ectomycorrhizal colonization, a factor assumed to be important for nutrient uptake in trees. We conclude that improved growth of Larix kaempferi in response to elevated [CO(2)] is accompanied by increased root biomass, but not by increased root activity. PMID:17169911

  15. Effect of troglitazone (Rezulin) on fructose 2,6-bisphosphate concentration and glucose metabolism in isolated rat hepatocytes.

    PubMed

    Raman, P; Foster, S E; Stokes, M C; Strenge, J K; Judd, R L

    1998-01-01

    The effect of troglitazone, an orally effective thiazolidinedione, on lactate- and glucagon-stimulated gluconeogenesis (in the absence of insulin) was examined in hepatocytes isolated from rats under different nutritional states. Hepatocytes obtained from fed or 20-24 hr fasted male Sprague-Dawley rats were incubated in Krebs-Henseleit Bicarbonate buffer (KHBC) (in presence or absence of 10.0 mM glucose) containing 2.0 mM [U-14C]lactate (0.1-0.25 microCi) with or without 10.0 nM glucagon and troglitazone (30.0 microM) or the appropriate vehicle. Aliquots were removed at specified endpoints and assayed for glucose and fructose 2,6-bisphosphate (F-2,6-P2) concentrations. In 20-24 hour starved hepatocytes, troglitazone produced a 26.1% inhibition of lactate-stimulated gluconeogenesis. This inhibitory effect of troglitazone on hepatic gluconeogenesis was further potentiated by incubation of the cells with glucose in vitro. In hepatocytes obtained from fasted rats (and incubated with 10 mM glucose in vitro) troglitazone reduced lactate-and glucagon-stimulated gluconeogenesis by 53% and 56%, respectively. This reduction in hepatic glucose production was associated with 1.06 and 1.04 fold increase in the hepatocyte F-2,6-P2 content. In isolated hepatocytes from fed animals and incubated with 10 mM glucose in vitro, troglitazone (15 and 30 microM) did not have any effect on either lactate- or glucagon-stimulated gluconeogenesis. However, 30 microM troglitazone significantly enhanced (36%) F-2,6-P2 concentrations during lactate-stimulated gluconeogenesis. These findings demonstrate that troglitazone decreases hepatic glucose production through alterations in the activity of one or more gluconeogenic/glycolytic enzymes, depending upon the nutritional state of the animal and the presence or absence of hormonal modulation. All of the effects of troglitazone in the present study were observed in the absence of insulin, suggesting an "insulinomimetic" effect. However, this does

  16. Nitrogen balance for wheat canopies (Triticum aestivum cv. Veery 10) grown under elevated and ambient CO2 concentrations

    NASA Technical Reports Server (NTRS)

    Smart, D. R.; Ritchie, K.; Bloom, A. J.; Bugbee, B. B.

    1998-01-01

    We examined the hypothesis that elevated CO2 concentration would increase NO3- absorption and assimilation using intact wheat canopies (Triticum aestivum cv. Veery 10). Nitrate consumption, the sum of plant absorption and nitrogen loss, was continuously monitored for 23 d following germination under two CO2 concentrations (360 and 1000 micromol mol-1 CO2) and two root zone NO3- concentrations (100 and 1000 mmol m3 NO3-). The plants were grown at high density (1780 m-2) in a 28 m3 controlled environment chamber using solution culture techniques. Wheat responded to 1000 micromol mol-1 CO2 by increasing carbon allocation to root biomass production. Elevated CO2 also increased root zone NO3- consumption, but most of this increase did not result in higher biomass nitrogen. Rather, nitrogen loss accounted for the greatest part of the difference in NO3- consumption between the elevated and ambient [CO2] treatments. The total amount of NO3(-)-N absorbed by roots or the amount of NO3(-)-N assimilated per unit area did not significantly differ between elevated and ambient [CO2] treatments. Instead, specific leaf organic nitrogen content declined, and NO3- accumulated in canopies growing under 1000 micromol mol-1 CO2. Our results indicated that 1000 micromol mol-1 CO2 diminished NO3- assimilation. If NO3- assimilation were impaired by high [CO2], then this offers an explanation for why organic nitrogen contents are often observed to decline in elevated [CO2] environments.

  17. Combined cadmium and elevated ozone affect concentrations of cadmium and antioxidant systems in wheat under fully open-air conditions.

    PubMed

    Guo, Hongyan; Tian, Ran; Zhu, Jianguo; Zhou, Hui; Pei, Daping; Wang, Xiaorong

    2012-03-30

    Pollution of the environment with both ozone (O(3)) and heavy metals has been steadily increasing. An understanding of their combined effects on plants, especially crops, is limited. Here we studied the effects of elevated O(3) on oxidative stress and bioaccumulation of cadmium (Cd) in wheat under Cd stress using a free-air concentration enrichment (FACE) system. In this field experiment in Jiangdu (Jiangsu Province, China), wheat plants were grown in pots containing soil with various concentrations of cadmium (0, 2, and 10 mg kg(-1) Cd was added to the soil) under ambient conditions and under elevated O(3) levels (50% higher than the ambient O(3)). Present results showed that elevated O(3) led to higher concentrations of Cd in wheat tissues (shoots, husk and grains) with respect to contaminated soil. Combined exposure to Cd and elevated O(3) levels strongly affected the antioxidant isoenzymes POD, APX and CAT and accelerated oxidative stress in wheat leaves. Our results suggest that elevated O(3) levels cause a reduction in food quality and safety. PMID:22285914

  18. Sensing glucose concentrations at GHz frequencies with a fully embedded Biomicro-electromechanical system (BioMEMS)

    PubMed Central

    Birkholz, M.; Ehwald, K.-E.; Basmer, T.; Kulse, P.; Reich, C.; Drews, J.; Genschow, D.; Haak, U.; Marschmeyer, S.; Matthus, E.; Schulz, K.; Wolansky, D.; Winkler, W.; Guschauski, T.; Ehwald, R.

    2013-01-01

    The progressive scaling in semiconductor technology allows for advanced miniaturization of intelligent systems like implantable biosensors for low-molecular weight analytes. A most relevant application would be the monitoring of glucose in diabetic patients, since no commercial solution is available yet for the continuous and drift-free monitoring of blood sugar levels. We report on a biosensor chip that operates via the binding competition of glucose and dextran to concanavalin A. The sensor is prepared as a fully embedded micro-electromechanical system and operates at GHz frequencies. Glucose concentrations derive from the assay viscosity as determined by the deflection of a 50 nm TiN actuator beam excited by quasi-electrostatic attraction. The GHz detection scheme does not rely on the resonant oscillation of the actuator and safely operates in fluidic environments. This property favorably combines with additional characteristics—(i) measurement times of less than a second, (ii) usage of biocompatible TiN for bio-milieu exposed parts, and (iii) small volume of less than 1 mm3—to qualify the sensor chip as key component in a continuous glucose monitor for the interstitial tissue. PMID:25332510

  19. Sensing glucose concentrations at GHz frequencies with a fully embedded Biomicro-electromechanical system (BioMEMS)

    NASA Astrophysics Data System (ADS)

    Birkholz, M.; Ehwald, K.-E.; Basmer, T.; Kulse, P.; Reich, C.; Drews, J.; Genschow, D.; Haak, U.; Marschmeyer, S.; Matthus, E.; Schulz, K.; Wolansky, D.; Winkler, W.; Guschauski, T.; Ehwald, R.

    2013-06-01

    The progressive scaling in semiconductor technology allows for advanced miniaturization of intelligent systems like implantable biosensors for low-molecular weight analytes. A most relevant application would be the monitoring of glucose in diabetic patients, since no commercial solution is available yet for the continuous and drift-free monitoring of blood sugar levels. We report on a biosensor chip that operates via the binding competition of glucose and dextran to concanavalin A. The sensor is prepared as a fully embedded micro-electromechanical system and operates at GHz frequencies. Glucose concentrations derive from the assay viscosity as determined by the deflection of a 50 nm TiN actuator beam excited by quasi-electrostatic attraction. The GHz detection scheme does not rely on the resonant oscillation of the actuator and safely operates in fluidic environments. This property favorably combines with additional characteristics—(i) measurement times of less than a second, (ii) usage of biocompatible TiN for bio-milieu exposed parts, and (iii) small volume of less than 1 mm3—to qualify the sensor chip as key component in a continuous glucose monitor for the interstitial tissue.

  20. Response of Archaeal Communities in the Rhizosphere of Maize and Soybean to Elevated Atmospheric CO2 Concentrations

    PubMed Central

    Nelson, David M.; Cann, Isaac K. O.; Mackie, Roderick I.

    2010-01-01

    Background Archaea are important to the carbon and nitrogen cycles, but it remains uncertain how rising atmospheric carbon dioxide concentrations ([CO2]) will influence the structure and function of soil archaeal communities. Methodology/Principal Findings We measured abundances of archaeal and bacterial 16S rRNA and amoA genes, phylogenies of archaeal 16S rRNA and amoA genes, concentrations of KCl-extractable soil ammonium and nitrite, and potential ammonia oxidation rates in rhizosphere soil samples from maize and soybean exposed to ambient (∼385 ppm) and elevated (550 ppm) [CO2] in a replicated and field-based study. There was no influence of elevated [CO2] on copy numbers of archaeal or bacterial 16S rRNA or amoA genes, archaeal community composition, KCl-extractable soil ammonium or nitrite, or potential ammonia oxidation rates for samples from maize, a model C4 plant. Phylogenetic evidence indicated decreased relative abundance of crenarchaeal sequences in the rhizosphere of soybean, a model leguminous-C3 plant, at elevated [CO2], whereas quantitative PCR data indicated no changes in the absolute abundance of archaea. There were no changes in potential ammonia oxidation rates at elevated [CO2] for soybean. Ammonia oxidation rates were lower in the rhizosphere of maize than soybean, likely because of lower soil pH and/or abundance of archaea. KCl-extractable ammonium and nitrite concentrations were lower at elevated than ambient [CO2] for soybean. Conclusion Plant-driven shifts in soil biogeochemical processes in response to elevated [CO2] affected archaeal community composition, but not copy numbers of archaeal genes, in the rhizosphere of soybean. The lack of a treatment effect for maize is consistent with the fact that the photosynthesis and productivity of maize are not stimulated by elevated [CO2] in the absence of drought. PMID:21209969

  1. Postoral glucose stimulation of intake and conditioned flavor preference in C57BL/6J mice: A concentration-response study

    PubMed Central

    Zukerman, Steven; Ackroff, Karen; Sclafani, Anthony

    2013-01-01

    In a recent study, intragastric (IG) self-infusion of 16% glucose stimulated 1-h intake and conditioned a preference for a flavored saccharin solution in C57BL/6J mice (Zukerman et al., 2011). Experiment 1 of the present study presents a concentration-response analysis of IG glucose-induced intake stimulation monitored by recording licking response every min of the 1 h/day sessions. Separate groups of food-restricted mice consumed a flavored saccharin solution (the CS−) paired with IG self-infusions of water (Test 0) followed by a different flavored solution (the CS+) paired with IG self-infusions of 2, 4, 8, 16, or 32% glucose (Tests 1–3). Following additional CS− and CS+ training sessions, a two-bottle CS+ vs. CS− choice test was conducted without infusions. Self-infusions of 8%, 16% or 32% glucose stimulated CS+ licking within 12 min of the first test session and even earlier in subsequent test sessions, and also conditioned significant CS+ preferences in the two-bottle test. The stimulation of early licking and CS+ preference increased as a function of glucose concentration. The amount of glucose solute self-infused increased with sugar concentration as did post-infusion blood glucose levels. The 2% glucose infusion did not stimulate CS+ intake and the 2% and 4% infusions failed to produce a CS+ preference in the 1-h test. Experiment 2 revealed that intraperitoneal self-infusions of 8% glucose, unlike IG glucose self-infusions, failed to stimulate CS+ licking or preference despite producing maximal increases in blood glucose levels. Taken together, these and other findings suggest that glucose rapidly produces concentration-dependent intestinal signals that stimulate intake and condition flavor preferences while postoral satiation signals limit total amounts consumed. PMID:23200639

  2. A Family History of Diabetes Modifies the Association between Elevated Urine Albumin Concentration and Hyperglycemia in Nondiabetic Mexican Adolescents

    PubMed Central

    Jiménez-Corona, Aida; Ávila-Hermosillo, Antonio; Nelson, Robert G.; Ramírez-López, Guadalupe

    2015-01-01

    We examined the frequency of elevated urine albumin concentration (UAC) and its association with metabolic syndrome (MetS) and metabolic markers in 515 nondiabetic Mexican adolescents stratified by family history of diabetes (FHD). UAC was measured in a first morning urine sample and considered elevated when excretion was ≥20 mg/mL. MetS was defined using International Diabetes Federation criteria. Fasting insulin, insulin resistance, and lipids were evaluated. Multivariate logistic regression was performed. Elevated UAC was present in 12.4% and MetS was present in 8.9% of the adolescents. No association was found between elevated UAC and MetS. Among adolescents with FHD, 18.4% were overweight and 20.7% were obese, whereas, among those without a FHD, 15.9% were overweight and 7.5% were obese. Hyperglycemia was higher in those with elevated UAC than in those without (44.4% versus 5.1%, p = 0.003). Hyperglycemia (OR = 9.8, 95% CI 1.6–59.4) and number of MetS components (OR = 4.5, 95% CI 1.5–13.3) were independently associated with elevated UAC. Among female participants, abdominal obesity was associated with elevated UAC (OR = 4.5, 95% CI 1.2–16.9). Conclusion. Elevated UAC was associated neither with MetS nor with any metabolic markers in nondiabetic adolescents. However, FHD modified the association of elevated UAC with hyperglycemia and the number of MetS components. PMID:26347891

  3. Cardiovascular responses to the ingestion of sugary drinks using a randomised cross-over study design: Does glucose attenuate the blood pressure-elevating effect of fructose?

    PubMed

    Grasser, Erik K; Dulloo, Abdul; Montani, Jean-Pierre

    2014-07-28

    Overconsumption of sugar-sweetened beverages has been implicated in the pathogenesis of CVD. The objective of the present study was to elucidate acute haemodynamic and microcirculatory responses to the ingestion of sugary drinks made from sucrose, glucose or fructose at concentrations similar to those often found in commercial soft drinks. In a randomised cross-over study design, twelve young healthy human subjects (seven men) ingested 500 ml tap water in which was dissolved 60 g of either sucrose, glucose or fructose, or an amount of fructose equivalent to that present in sucrose (i.e. 30 g fructose). Continuous cardiovascular monitoring was performed for 30 min before and at 60 min after ingestion of sugary drinks, and measurements included beat-to-beat blood pressure (BP) and impedance cardiography. Additionally, microvascular endothelial function testing was performed after iontophoresis of acetylcholine and sodium nitroprusside using laser Doppler flowmetry. Ingestion of fructose (60 or 30 g) increased diastolic and mean BP to a greater extent than the ingestion of 60 g of either glucose or sucrose (P< 0.05). Ingestion of sucrose and glucose increased cardiac output (CO; P< 0.05), index of contractility (P< 0.05) and stroke volume (P< 0.05), but reduced total peripheral resistance (TPR; P< 0.05), which contrasts with the tendency of fructose (60 and 30 g) to increase resistance. Microvascular endothelial function did not differ in response to the ingestion of various sugary drinks. In conclusion, ingestion of fructose, but not sucrose, increases BP in healthy human subjects. Although sucrose comprises glucose and fructose, its changes in TPR and CO are more related to glucose than to fructose. PMID:24780643

  4. Differential Responses in Two Varieties of Winter Wheat to Elevated Ozone Concentration Under Fully Open-air Field Conditions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two modern cultivars (Yangmai16 (Y16) and Yangfumai 2 (Y2)) of winter wheat (Triticum aestivum L.) of almost identical phenology were investigated for impacts of elevated ozone concentration (E-O3) on physiological characters related to photosynthesis under fully open-air field conditions in China. ...

  5. Elevated IgG levels against specific bacterial antigens in obese patients with diabetes and in mice with diet-induced obesity and glucose intolerance.

    PubMed

    Mohammed, Nadeem; Tang, Lihua; Jahangiri, Anisa; de Villiers, Willem; Eckhardt, Erik

    2012-09-01

    High fat diets increase the risk for insulin resistance by promoting inflammation. The cause of inflammation is unclear, but germfree mouse studies have implicated commensal gut bacteria. We tested whether diet-induced obesity, diabetes, and inflammation are associated with anti-bacterial IgG. Blood from lean and obese healthy volunteers or obese patients with diabetes were analyzed by ELISA for IgG against extracts of potentially pathogenic and pro-biotic strains of Escherichia coli (LF-82 and Nissle), Bacteroides thetaiotaomicron, and Lactobacillus acidophilus, and for circulating tumor necrosis factor α (TNFα). C57Bl/6 mice were fed low- or high-fat diets (10% or 60% kcal from fat) for 10 weeks and tested for anti-bacterial IgG, bodyweight, fasting glucose, and inflammation. Obese diabetic patients had significantly more IgG against extracts of E. coli LF-82 compared with lean controls, whereas IgG against extracts of the other bacteria was unchanged. Circulating TNFα was elevated and correlated with IgG against the LF-82 extract. Mice fed high-fat diets had increased fasting glucose levels, elevated TNFα and neutrophils, and significantly more IgG against the LF-82 extracts. Diabetes in obesity is characterized by increased IgG against specific bacterial antigens. Specific commensal bacteria may mediate inflammatory effects of high-fat diets. PMID:22424821

  6. Redox Signal-mediated Enhancement of the Temperature Sensitivity of Transient Receptor Potential Melastatin 2 (TRPM2) Elevates Glucose-induced Insulin Secretion from Pancreatic Islets.

    PubMed

    Kashio, Makiko; Tominaga, Makoto

    2015-05-01

    Transient receptor potential melastatin 2 (TRPM2) is a thermosensitive Ca(2+)-permeable cation channel expressed by pancreatic β cells where channel function is constantly affected by body temperature. We focused on the physiological functions of redox signal-mediated TRPM2 activity at body temperature. H2O2, an important molecule in redox signaling, reduced the temperature threshold for TRPM2 activation in pancreatic β cells of WT mice but not in TRPM2KO cells. TRPM2-mediated [Ca(2+)]i increases were likely caused by Ca(2+) influx through the plasma membrane because the responses were abolished in the absence of extracellular Ca(2+). In addition, TRPM2 activation downstream from the redox signal plus glucose stimulation enhanced glucose-induced insulin secretion. H2O2 application at 37 °C induced [Ca(2+)]i increases not only in WT but also in TRPM2KO β cells. This was likely due to the effect of H2O2 on KATP channel activity. However, the N-acetylcysteine-sensitive fraction of insulin secretion by WT islets was increased by temperature elevation, and this temperature-dependent enhancement was diminished significantly in TRPM2KO islets. These data suggest that endogenous redox signals in pancreatic β cells elevate insulin secretion via TRPM2 sensitization and activity at body temperature. The results in this study could provide new therapeutic approaches for the regulation of diabetic conditions by focusing on the physiological function of TRPM2 and redox signals. PMID:25817999

  7. Redox Signal-mediated Enhancement of the Temperature Sensitivity of Transient Receptor Potential Melastatin 2 (TRPM2) Elevates Glucose-induced Insulin Secretion from Pancreatic Islets*

    PubMed Central

    Kashio, Makiko; Tominaga, Makoto

    2015-01-01

    Transient receptor potential melastatin 2 (TRPM2) is a thermosensitive Ca2+-permeable cation channel expressed by pancreatic β cells where channel function is constantly affected by body temperature. We focused on the physiological functions of redox signal-mediated TRPM2 activity at body temperature. H2O2, an important molecule in redox signaling, reduced the temperature threshold for TRPM2 activation in pancreatic β cells of WT mice but not in TRPM2KO cells. TRPM2-mediated [Ca2+]i increases were likely caused by Ca2+ influx through the plasma membrane because the responses were abolished in the absence of extracellular Ca2+. In addition, TRPM2 activation downstream from the redox signal plus glucose stimulation enhanced glucose-induced insulin secretion. H2O2 application at 37 °C induced [Ca2+]i increases not only in WT but also in TRPM2KO β cells. This was likely due to the effect of H2O2 on KATP channel activity. However, the N-acetylcysteine-sensitive fraction of insulin secretion by WT islets was increased by temperature elevation, and this temperature-dependent enhancement was diminished significantly in TRPM2KO islets. These data suggest that endogenous redox signals in pancreatic β cells elevate insulin secretion via TRPM2 sensitization and activity at body temperature. The results in this study could provide new therapeutic approaches for the regulation of diabetic conditions by focusing on the physiological function of TRPM2 and redox signals. PMID:25817999

  8. Will elevated carbon dioxide concentration amplify the benefits of nitrogen fixation in legumes?

    SciTech Connect

    Rogers, A.; Ainsworth, E. A.; Leakey, A. D. B.

    2009-11-01

    Growth at elevated [CO{sub 2}] stimulates photosynthesis and increases carbon (C) supply in all C3 species. A sustained and maximal stimulation in productivity at elevated [CO{sub 2}] requires an enhanced nutrient supply to match the increase in C acquisition. The ability of legumes to exchange C for nitrogen (N) with their N{sub 2}-fixing symbionts has led to the hypothesis that legumes will have a competitive advantage over nonleguminous species when grown at elevated [CO{sub 2}]. On balance, evidence suggests that in managed systems, legumes are more responsive to elevated [CO{sub 2}] than other plants (e.g. Ainsworth and Long, 2005); however, in natural ecosystems, nutrient availability can limit the response of legumes to elevated [CO{sub 2}] (Hungate et al., 2004; van Groenigen et al., 2006). Here, we consider these observations, outline the mechanisms that underlie them, and examine recent work that advances our understanding of how legumes respond to growth at elevated [CO{sub 2}]. First we highlight the global importance of legumes and provide a brief overview of the symbiotic relationship.

  9. Glycosylation-related genes in NS0 cells are insensitive to moderately elevated ammonium concentrations

    PubMed Central

    Brodsky, Arthur Nathan; Caldwell, Mary; Bae, Sooneon; Harcum, Sarah W.

    2014-01-01

    NS0 and Chinese hamster ovary (CHO) cell lines are used to produce recombinant proteins for human therapeutics; however, ammonium accumulation can negatively impact cell growth, recombinant protein production, and protein glycosylation. To improve product quality and decrease costs, the relationship between ammonium and protein glycosylation needs to be elucidated. While ammonium has been shown to adversely affect glycosylation-related gene expression in CHO cells, NS0 studies have not been performed. Therefore, this study sought to determine if glycosylation in NS0 cells were ammonium-sensitive at the gene expression level. Using a DNA microarray that contained mouse glycosylation-related and housekeeping genes, the of these genes was analysed in response to various culture conditions – elevated ammonium, elevated salt, and elevated ammonium with proline. Surprisingly, no significant differences in gene expression levels were observed between the control and these conditions. Further, the elevated ammonium cultures were analysed using real-time quantitative reverse transcriptase PCR (qRT-PCR) for key glycosylation genes, and the qRT-PCR results corroborated the DNA microarray results, demonstrating that NS0 cells are ammonium-insensitive at the gene expression level. Since NS0 are known to have elevated nucleotide sugar pools under ammonium stress, and none of the genes directly responsible for these metabolic pools were changed, consequently cellular control at the translational or substrate-level must be responsible for the universally observed decreased glycosylation quality under elevated ammonium. PMID:25062658

  10. The Structure of a Sugar Transporter of the Glucose EIIC Superfamily Provides Insight into the Elevator Mechanism of Membrane Transport.

    PubMed

    McCoy, Jason G; Ren, Zhenning; Stanevich, Vitali; Lee, Jumin; Mitra, Sharmistha; Levin, Elena J; Poget, Sebastien; Quick, Matthias; Im, Wonpil; Zhou, Ming

    2016-06-01

    The phosphoenolpyruvate:carbohydrate phosphotransferase systems are found in bacteria, where they play central roles in sugar uptake and regulation of cellular uptake processes. Little is known about how the membrane-embedded components (EIICs) selectively mediate the passage of carbohydrates across the membrane. Here we report the functional characterization and 2.55-Å resolution structure of a maltose transporter, bcMalT, belonging to the glucose superfamily of EIIC transporters. bcMalT crystallized in an outward-facing occluded conformation, in contrast to the structure of another glucose superfamily EIIC, bcChbC, which crystallized in an inward-facing occluded conformation. The structures differ in the position of a structurally conserved substrate-binding domain that is suggested to play a central role in sugar transport. In addition, molecular dynamics simulations suggest a potential pathway for substrate entry from the periplasm into the bcMalT substrate-binding site. These results provide a mechanistic framework for understanding substrate recognition and translocation for the glucose superfamily EIIC transporters. PMID:27161976

  11. Pre-germinated brown rice prevents high-fat diet induced hyperglycemia through elevated insulin secretion and glucose metabolism pathway in C57BL/6J strain mice

    PubMed Central

    Shen, Kuo-Ping; Hao, Chi-Long; Yen, Hsueh-Wei; Chen, Chun-Yen; Wu, Bin-Nan; Lin, Hui-Li

    2015-01-01

    This study investigated the effect and mechanism of pre-germinated brown rice (PGBR) prevented hyperglycemia in C57BL/6J mice fed high-fat-diet (HFD). Normal six-week-old mice were randomly divided into three groups. Group 1 was fed standard-regular-diet (SRD) and group 2 was fed HFD for 16 weeks. In group 3, the mice were fed a HFD with its carbohydrate replaced with PGBR for 16 weeks. Comparing the SRD and HFD groups, we found the HFD group had higher blood pressure, higher concentrations of blood glucose and HbA1c. The HFD group had less protein expression of insulin receptor (IR), insulin receptor substrate-1 (IRS-1), phosphatidylinositol-3-kinase (PI3K), glucose transporter-4 (GLUT-4) and glucokinase (GCK) and greater expression of glucogen synthase kinase (GSK) in skeletal muscle. The HFD group also had less expression of IR, serine/threonine kinase PI3K-linked protein kinase B (Akt/PKB), AMP-activated protein kinase (AMPK), GCK and peroxisome proliferator-activated receptor γ (PPARγ) in liver. In the HFD + PGBR group, the PGBR could reverse the disorders of blood pressure, blood glucose, HbA1c and increase insulin concentration. PGBR increased the IR, IRS-1, PI3K, Akt, GLUT-1 and GLUT-4 proteins, and ameliorated AMPK, GCK, GSK and PPARγ proteins. Together, PGBR prevented HFD-induced hyperglycemia through improving insulin levels, insulin receptor, glucose transporters and enhancing glucose metabolism. PMID:25834303

  12. Sepsis does not alter red blood cell glucose metabolism or Na+ concentration: A 2H-, 23Na-NMR study

    SciTech Connect

    Hotchkiss, R.S.; Song, S.K.; Ling, C.S.; Ackerman, J.J.; Karl, I.E. )

    1990-01-01

    The effects of sepsis on intracellular Na+ concentration ((Na+)i) and glucose metabolism were examined in rat red blood cells (RBCs) by using 23Na- and 2H-nuclear magnetic resonance (NMR) spectroscopy. Sepsis was induced in 15 halothane-anesthetized female Sprague-Dawley rats by using the cecal ligation and perforation technique; 14 control rats underwent cecal manipulation without ligation. The animals were fasted for 36 h, but allowed free access to water. At 36 h postsurgery, RBCs were examined by 23Na-NMR by using dysprosium tripolyphosphate as a chemical shift reagent. Human RBCs from 17 critically ill nonseptic patients and from 7 patients who were diagnosed as septic were also examined for (Na+)i. Five rat RBC specimens had (Na+)i determined by both 23Na-NMR and inductively coupled plasma-atomic emission spectroscopy (ICP-AES). For glucose metabolism studies, RBCs from septic and control rats were suspended in modified Krebs-Henseleit buffer containing (6,6-2H2)glucose and examined by 2H-NMR. No significant differences in (Na+)i or glucose utilization were found in RBCs from control or septic rats. There were no differences in (Na+)i in the two groups of patients. The (Na+)i determined by NMR spectroscopy agreed closely with measurements using ICP-AES and establish that 100% of the (Na+)i of the RBC is visible by NMR. Glucose measurements determined by 2H-NMR correlated closely (correlation coefficient = 0.93) with enzymatic analysis. These studies showed no evidence that sepsis disturbed RBC membrane function or metabolism.

  13. Concomitant Intake of Quercetin with a Grain-Based Diet Acutely Lowers Postprandial Plasma Glucose and Lipid Concentrations in Pigs

    PubMed Central

    Wein, Silvia; Wolffram, Siegfried

    2014-01-01

    Treatment goals of diabetes mellitus type 2 (DMT2) include glycemic control and reduction of nonglycemic risk factors, for example, dyslipidemia. Quercetin, a plant-derived polyphenol, often discussed for possible antidiabetic effects, was investigated for acute postprandial glucose- and lipid-lowering effects in healthy growing pigs. Male pigs (n = 16, body weight = BW 25–30 kg) were fed flavonoid-poor grain-based meals without (GBM) or with quercetin (GBMQ). In a first experiment, postprandial plasma concentrations of glucose, nonesterified fatty acids (NEFA), and triacylglycerols were analyzed in 8 pigs receiving 500 g of either GBM or GBMQ (10 mg/kg BW) in a cross-over design. Blood samples were collected before, and up to 5 h every 30 min, as well as 6 and 8 h after the feeding. In the second experiment, 2 h after ingestions of 1000 g of either GBM or GBMQ (50 mg/kg BW) animals were sacrificed; gastric content was collected and analyzed for dry matter content. Quercetin ingestion reduced postprandial glucose, NEFA, and TG concentration, but two hours after ingestion of the meal no effect on gastric emptying was observed. Our results point to inhibitory effects of quercetin on nutrient absorption, which appear not to be attributable to delayed gastric emptying. PMID:24847478

  14. Longitudinal 3-week tracking of blood glucose concentration from thermo-optical response measurements on human skin

    NASA Astrophysics Data System (ADS)

    Yeh, Shu-jen; Kantor, Stan; Hanna, Charles; Shain, Eric; Hohs, Ronald; Khalil, Omar S.

    2006-08-01

    We designed a dual-sensor instrument for measuring optical signals from the arms of human volunteers. The instrument had two temperature-controlled localized reflectance optical probes. Each probe had one illumination fiber and four detection fibers at different source-detector distances. The two probes were maintained at 30 °C. Thirty seconds after contact with the skin one was heated and the other was cooled at the same rate. The effect of heating and cooling on the signal was measured and correlated with blood glucose concentration. The measurements were performed 3 to 5 times a day for each volunteer over the span of three weeks. The data points from the first two weeks were used to establish a calibration model for each volunteer, which was used to predict glucose values from the third week optical data. Successftil calibration was possible for two of the three volunteers.

  15. Intravenous lipid and amino acids briskly increase plasma glucose concentrations in small premature infants.

    PubMed

    Savich, R D; Finley, S L; Ogata, E S

    1988-07-01

    We determined the glycemic response to intravenous lipid infusion alone, lipid with amino acids, or amino acids alone in 15 very small premature infants receiving constant glucose infusion during early life. Infants who received lipid or lipid and amino acids demonstrated significant increases in glucose compared with infants who received amino acids. The combination of lipid and amino acids resulted in an earlier increase than lipid alone. Although plasma insulin did not change in all three groups, infants who received amino acids alone demonstrated an appropriate increase in glucagon. These data suggest that lipid infusion, a commonly used means of providing nutrition to premature infants, may cause significant disturbances in glucoregulation, particularly when administered with amino acids. PMID:3132930

  16. Application of granular ferric hydroxides for removal elevated concentrations of arsenic from mine waters

    NASA Astrophysics Data System (ADS)

    Szlachta, Małgorzata; Włodarczyk, Paweł; Wójtowicz, Patryk

    2015-04-01

    Arsenic is naturally occurring element in the environment. Over three hundred minerals are known to contain some form of arsenic and among them arsenopyrite is the most common one. Arsenic-bearing minerals are frequently associated with ores containing mined metals such as copper, tin, nickel, lead, uranium, zinc, cobalt, platinum and gold. In the aquatic environment arsenic is typically present in inorganic forms, mainly in two oxidation states (+5, +3). As(III) is dominant in more reduced conditions, whereas As(V) is mostly present in an oxidizing environment. However, due to certain human activities the elevated arsenic levels in aquatic ecosystems are arising to a serious environmental problem. High arsenic concentrations found in surface and groundwaters, in some regions originate from mining activities and ore processing. Therefore, the major concern of mining industry is to maintain a good quality of effluents discharged in large volumes. This requires constant monitoring of effluents quality that guarantee the efficient protection of the receiving waters and reacting to possible negative impact of contamination on local communities. A number of proven technologies are available for arsenic removal from waters and wastewaters. In the presented work special attention is given to the adsorption method as a technically feasible, commonly applied and effective technique for the treatment of arsenic rich mine effluents. It is know that arsenic has a strong affinity towards iron rich materials. Thus, in this study the granular ferric hydroxides (CFH 12, provided by Kemira Oyj, Finland) was applied to remove As(III) and As(V) from aqueous solutions. The batch adsorption experiments were carried out to assess the efficiency of the tested Fe-based material under various operating parameters, including composition of treated water, solution pH and temperature. The results obtained from the fixed bed adsorption tests demonstrated the benefits of applying granular

  17. Elevated CO(2) concentration affects leaf photosynthesis-nitrogen relationships in Pinus taeda over nine years in FACE.

    PubMed

    Crous, Kristine Y; Walters, Michael B; Ellsworth, David S

    2008-04-01

    To investigate whether long-term elevated carbon dioxide concentration ([CO(2)]) causes declines in photosynthetic enhancement and leaf nitrogen (N) owing to limited soil fertility, we measured photosynthesis, carboxylation capacity and area-based leaf nitrogen concentration (N(a)) in Pinus taeda L. growing in a long-term free-air CO(2) enrichment (FACE) facility at an N-limited site. We also determined how maximum rates of carboxylation (V(cmax)) and electron transport (J(max)) varied with N(a) under elevated [CO(2)]. In trees exposed to elevated [CO(2)] for 5 to 9 years, the slope of the relationship between leaf photosynthetic capacity (A(net-Ca)) and N(a) was significantly reduced by 37% in 1-year-old needles, whereas it was unaffected in current-year needles. The slope of the relationships of both V(cmax) and J(max) with N(a) decreased in 1-year-old needles after up to 9 years of growth in elevated [CO(2)], which was accompanied by a 15% reduction in N allocation to the carboxylating enzyme. Nitrogen fertilization (110 kg N ha(-1)) in the ninth year of exposure to elevated [CO(2)] restored the slopes of the relationships of V(cmax) and J(max) with N(a) to those of control trees (i.e., in ambient [CO(2)]). The J(max):V(cmax) ratio was unaffected by either [CO(2)] or N fertilization. Changes in the apparent allocation of N to photosynthetic components may be an important adjustment in pines exposed to elevated [CO(2)] on low-fertility sites. We conclude that fundamental relationships between photosynthesis or its component processes with N(a) may be altered in aging pine needles after more than 5 years of exposure to elevated atmospheric [CO(2)]. PMID:18244946

  18. Changes in the activities of starch metabolism enzymes in rice grains in response to elevated CO2 concentration

    NASA Astrophysics Data System (ADS)

    Xie, Li-Yong; Lin, Er-Da; Zhao, Hong-Liang; Feng, Yong-Xiang

    2016-05-01

    The global atmospheric CO2 concentration is currently (2012) 393.1 μmol mol-1, an increase of approximately 42 % over pre-industrial levels. In order to understand the responses of metabolic enzymes to elevated CO2 concentrations, an experiment was conducted using the Free Air CO2 Enrichment (FACE )system. Two conventional japonica rice varieties ( Oryza sativa L. ssp. japonica) grown in North China, Songjing 9 and Daohuaxiang 2, were used in this study. The activities of ADPG pyrophosphorylase, soluble and granule-bound starch synthases, and soluble and granule-bound starch branching enzymes were measured in rice grains, and the effects of elevated CO2 on the amylose and protein contents of the grains were analyzed. The results showed that elevated CO2 levels significantly increased the activity of ADPG pyrophosphorylase at day 8, 24, and 40 after flower, with maximum increases of 56.67 % for Songjing 9 and 21.31 % for Daohuaxiang 2. Similarly, the activities of starch synthesis enzymes increased significantly from the day 24 after flower to the day 40 after flower, with maximum increases of 36.81 % for Songjing 9 and 66.67 % for Daohuaxiang 2 in soluble starch synthase (SSS), and 25.00 % for Songjing 9 and 36.44 % for Daohuaxiang 2 in granule-bound starch synthase (GBSS), respectively. The elevated CO2 concentration significantly increased the activity of soluble starch branching enzyme (SSBE) at day 16, 32, and 40 after flower, and also significantly increased the activity of granule-bound starch branching enzyme (GBSBE) at day 8, 32, and 40 after flower. The elevated CO2 concentration increased the peak values of enzyme activity, and the timing of the activity peaks for SSS and GBSBE were earlier in Songjing 9 than in Daohuaxiang 2. There were obvious differences in developmental stages between the two varieties of rice, which indicated that the elevated CO2 concentration increased enzyme activity expression and starch synthesis, affecting the final contents

  19. Changes in the activities of starch metabolism enzymes in rice grains in response to elevated CO2 concentration.

    PubMed

    Xie, Li-Yong; Lin, Er-Da; Zhao, Hong-Liang; Feng, Yong-Xiang

    2016-05-01

    The global atmospheric CO(2) concentration is currently (2012) 393.1 μmol mol(-1), an increase of approximately 42 % over pre-industrial levels. In order to understand the responses of metabolic enzymes to elevated CO(2) concentrations, an experiment was conducted using the Free Air CO(2) Enrichment (FACE )system. Two conventional japonica rice varieties (Oryza sativa L. ssp. japonica) grown in North China, Songjing 9 and Daohuaxiang 2, were used in this study. The activities of ADPG pyrophosphorylase, soluble and granule-bound starch synthases, and soluble and granule-bound starch branching enzymes were measured in rice grains, and the effects of elevated CO(2) on the amylose and protein contents of the grains were analyzed. The results showed that elevated CO(2) levels significantly increased the activity of ADPG pyrophosphorylase at day 8, 24, and 40 after flower, with maximum increases of 56.67 % for Songjing 9 and 21.31 % for Daohuaxiang 2. Similarly, the activities of starch synthesis enzymes increased significantly from the day 24 after flower to the day 40 after flower, with maximum increases of 36.81 % for Songjing 9 and 66.67 % for Daohuaxiang 2 in soluble starch synthase (SSS), and 25.00 % for Songjing 9 and 36.44 % for Daohuaxiang 2 in granule-bound starch synthase (GBSS), respectively. The elevated CO(2) concentration significantly increased the activity of soluble starch branching enzyme (SSBE) at day 16, 32, and 40 after flower, and also significantly increased the activity of granule-bound starch branching enzyme (GBSBE) at day 8, 32, and 40 after flower. The elevated CO(2) concentration increased the peak values of enzyme activity, and the timing of the activity peaks for SSS and GBSBE were earlier in Songjing 9 than in Daohuaxiang 2. There were obvious differences in developmental stages between the two varieties of rice, which indicated that the elevated CO(2) concentration increased enzyme activity expression and starch synthesis, affecting the

  20. Simultaneous fermentation of glucose and xylose at elevated temperatures co-produces ethanol and xylitol through overexpression of a xylose-specific transporter in engineered Kluyveromyces marxianus.

    PubMed

    Zhang, Biao; Zhang, Jia; Wang, Dongmei; Han, Ruixiang; Ding, Rui; Gao, Xiaolian; Sun, Lianhong; Hong, Jiong

    2016-09-01

    Engineered Kluyveromyces marxianus strains were constructed through over-expression of various transporters for simultaneous co-fermentation of glucose and xylose. The glucose was converted into ethanol, whereas xylose was converted into xylitol which has higher value than ethanol. Over-expressing xylose-specific transporter ScGAL2-N376F mutant enabled yeast to co-ferment glucose and xylose and the co-fermentation ability was obviously improved through increasing ScGAL2-N376F expression. The production of glycerol was blocked and acetate production was reduced by disrupting gene KmGPD1. The obtained K. marxianus YZJ119 utilized 120g/L glucose and 60g/L xylose simultaneously and produced 50.10g/L ethanol and 55.88g/L xylitol at 42°C. The yield of xylitol from consumed xylose was over 98% (0.99g/g). Through simultaneous saccharification and co-fermentation at 42°C, YZJ119 produced a maximal concentration of 44.58g/L ethanol and 32.03g/L xylitol or 29.82g/L ethanol and 31.72g/L xylitol, respectively, from detoxified or non-detoxified diluted acid pretreated corncob. PMID:27240239

  1. Effects of Glucose Concentration on Propofol Cardioprotection against Myocardial Ischemia Reperfusion Injury in Isolated Rat Hearts.

    PubMed

    Yao, Xinhua; Li, Yalan; Tao, Mingzhe; Wang, Shuang; Zhang, Liangqing; Lin, Jiefu; Xia, Zhengyuan; Liu, Hui-Min

    2015-01-01

    The anesthetic propofol confers cardioprotection against myocardial ischemia-reperfusion injury (IRI) by reducing reactive oxygen species (ROS). However, its cardioprotection on patients is inconsistent. Similarly, the beneficial effect of tight glycemic control during cardiac surgery in patients has recently been questioned. We postulated that low glucose (LG) may promote ROS formation through enhancing fatty acid (FA) oxidation and unmask propofol cardioprotection during IRI. Rat hearts were isolated and randomly assigned to be perfused with Krebs-Henseleit solution with glucose at 5.5 mM (LG) or 8 mM (G) in the absence or presence of propofol (5 μg/mL) or propofol plus trimetazidine (TMZ). Hearts were subjected to 35 minutes of ischemia followed by 60 minutes of reperfusion. Myocardial infarct size (IS) and cardiac CK-MB were significantly higher in LG than in G group (P < 0.05), associated with reduced left ventricular developed pressure and increases in postischemic cardiac contracture. Cardiac 15-F2t-isoprostane was higher, accompanied with higher cardiac lipid transporter CD36 protein expression in LG. Propofol reduced IS, improved cardiac function, and reduced CD36 in G but not in LG. TMZ facilitated propofol cardioprotection in LG. Therefore, isolated heart with low glucose lost sensitivity to propofol treatment through enhancing FA oxidation and TMZ supplementation restored the sensitivity to propofol. PMID:26491698

  2. Effects of Glucose Concentration on Propofol Cardioprotection against Myocardial Ischemia Reperfusion Injury in Isolated Rat Hearts

    PubMed Central

    Yao, Xinhua; Li, Yalan; Tao, Mingzhe; Wang, Shuang; Zhang, Liangqing; Lin, Jiefu; Xia, Zhengyuan; Liu, Hui-min

    2015-01-01

    The anesthetic propofol confers cardioprotection against myocardial ischemia-reperfusion injury (IRI) by reducing reactive oxygen species (ROS). However, its cardioprotection on patients is inconsistent. Similarly, the beneficial effect of tight glycemic control during cardiac surgery in patients has recently been questioned. We postulated that low glucose (LG) may promote ROS formation through enhancing fatty acid (FA) oxidation and unmask propofol cardioprotection during IRI. Rat hearts were isolated and randomly assigned to be perfused with Krebs-Henseleit solution with glucose at 5.5 mM (LG) or 8 mM (G) in the absence or presence of propofol (5 μg/mL) or propofol plus trimetazidine (TMZ). Hearts were subjected to 35 minutes of ischemia followed by 60 minutes of reperfusion. Myocardial infarct size (IS) and cardiac CK-MB were significantly higher in LG than in G group (P < 0.05), associated with reduced left ventricular developed pressure and increases in postischemic cardiac contracture. Cardiac 15-F2t-isoprostane was higher, accompanied with higher cardiac lipid transporter CD36 protein expression in LG. Propofol reduced IS, improved cardiac function, and reduced CD36 in G but not in LG. TMZ facilitated propofol cardioprotection in LG. Therefore, isolated heart with low glucose lost sensitivity to propofol treatment through enhancing FA oxidation and TMZ supplementation restored the sensitivity to propofol. PMID:26491698

  3. Obese Mexican American children have elevated MCP-1, TNF-alpha, monocyte concentration, and dyslipidemia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Obesity is an independent risk factor for chronic disease. The prevalence of obesity is especially high among Mexican American children. Peripheral blood monocytes are altered with obesity contributing to elevated systemic inflammation and increased risk of chronic disease. In addition, obesity alte...

  4. Glucose concentration in the blood of intact and alloxan-treated mice after pretreatment with commercial preparations of Stevia rebaudiana (Bertoni).

    PubMed

    Raskovic, Aleksandar; Gavrilovic, Maja; Jakovljevic, Vida; Sabo, Jan

    2004-01-01

    The study was concerned with the effect of mice pretreatment with two commercial products of Stevia rebaudiana Bertoni on the blood glucose concentration. One group of mice was pretreated four days with 200 mg/kg of Stevita (Stevita Co, INC, Arlington Texas) (stevia) and the other with 20 mg/kg of Clear Steviosides liquid (Stevita Co, INC, Herbal supplement, Brazil) (stevioside), whereas the animals of control group received at the same time physiological solution. Blood glucose concentration was measured before pretreatment and four days after that. The changes in glucose level were provoked by glucose-tolerance test (500 mg/kg, p.o.) and subcutaneous injection of adrenaline (0.2 mg/kg). The same procedure of measuring blood glucose was applied on the mice with alloxan-induced diabetes mellitus (two doses of 100 mg/kg with a 24-hour interval). Blood glucose levels in mice pretreated with stevia and stevioside were lower compared with control (7.82:6.82:8.01). Also, a smaller increase in this parameter compared to control was registered with pretreated mice in the glucose-tolerance test, pretreatment with stevioside being again more effective (8.68:6.36:5.82). Pretreatment with stevioside caused no significant increase in blood glucose concentration after administering adrenaline, which was not the case with the animals pretreated with stevia and control. Pretreatment with stevia, and to a greater extent with stevioside, protected test animals from the toxic action of alloxan compared with controls. PMID:15230335

  5. The effect of 3-bromopyruvate on human colorectal cancer cells is dependent on glucose concentration but not hexokinase II expression

    PubMed Central

    Ho, Nelson; Morrison, Jodi; Silva, Andreza; Coomber, Brenda L.

    2016-01-01

    Cancer cells heavily rely on the glycolytic pathway regardless of oxygen tension. Hexokinase II (HKII) catalyses the first irreversible step of glycolysis and is often overexpressed in cancer cells. 3-Bromopyruvate (3BP) has been shown to primarily target HKII, and is a promising anti-cancer compound capable of altering critical metabolic pathways in cancer cells. Abnormal vasculature within tumours leads to heterogeneous microenvironments, including glucose availability, which may affect drug sensitivity. The aim of the present study was to elucidate the mechanisms by which 3BP acts on colorectal cancer (CRC) cells with focus on the HKII/Akt signalling axis. High HKII-expressing cell lines were more sensitive to 3BP than low HKII-expressing cells. 3BP-induced rapid Akt phosphorylation at site Thr-308 and cell death via both apoptotic and necrotic mechanisms. Cells grown under lower glucose concentrations showed greater resistance towards 3BP. Cells with HKII knockdown showed no changes in 3BP sensitivity, suggesting the effects of 3BP are independent of HKII expression. These results emphasize the importance of the tumour microenvironment and glucose availability when considering therapeutic approaches involving metabolic modulation. PMID:26740252

  6. The effect of 3-bromopyruvate on human colorectal cancer cells is dependent on glucose concentration but not hexokinase II expression.

    PubMed

    Ho, Nelson; Morrison, Jodi; Silva, Andreza; Coomber, Brenda L

    2016-01-01

    Cancer cells heavily rely on the glycolytic pathway regardless of oxygen tension. Hexokinase II (HKII) catalyses the first irreversible step of glycolysis and is often overexpressed in cancer cells. 3-Bromopyruvate (3BP) has been shown to primarily target HKII, and is a promising anti-cancer compound capable of altering critical metabolic pathways in cancer cells. Abnormal vasculature within tumours leads to heterogeneous microenvironments, including glucose availability, which may affect drug sensitivity. The aim of the present study was to elucidate the mechanisms by which 3BP acts on colorectal cancer (CRC) cells with focus on the HKII/Akt signalling axis. High HKII-expressing cell lines were more sensitive to 3BP than low HKII-expressing cells. 3BP-induced rapid Akt phosphorylation at site Thr-308 and cell death via both apoptotic and necrotic mechanisms. Cells grown under lower glucose concentrations showed greater resistance towards 3BP. Cells with HKII knockdown showed no changes in 3BP sensitivity, suggesting the effects of 3BP are independent of HKII expression. These results emphasize the importance of the tumour microenvironment and glucose availability when considering therapeutic approaches involving metabolic modulation. PMID:26740252

  7. Elevated Fibroblast Growth Factor 23 Concentration: Prediction of Mortality among Chronic Kidney Disease Patients

    PubMed Central

    Chathoth, Shahanas; Al-Mueilo, Samir; Cyrus, Cyril; Vatte, Chittibabu; Al-Nafaie, Awatif; Al-Ali, Rudaynah; Keating, Brendan J.; Al-Muhanna, Fahad; Al Ali, Amein

    2015-01-01

    Background The osteocyte-derived hormone, fibroblast growth factor 23 (FGF23), regulates the phosphorus metabolism and suppresses 1,25-dihydroxyvitamin D production, thereby mitigating hyperphosphatemia in patients with renal disorders. An elevated FGF23 level is suggested to be an early biomarker of altered phosphorus metabolism in the initial stages of chronic kidney disease (CKD) and acts as a strong predictor of mortality in dialysis patients. In the Saudi population, there is no report on the FGF23 level in CKD patients to date. This study aims to estimate the plasma FGF23 levels in the Saudi population and to correlate it with its clinical manifestations in order to ascertain its role in the pathogenesis of CKD patients. Methods The FGF23 level in the plasma samples was determined using ELISA in a diverse cohort of 89 cases with stage 3-5 CKD and 100 healthy subjects. The plasma FGF23 level was correlated with other biochemical parameters. Results The results revealed that the FGF23 level was markedly elevated among CKD patients compared to the control group, and a significant inverse correlation was observed between the FGF23 level and glomerular filtration rate. FGF23 elevation was approximately 40-fold among stage 5 patients compared to the control, while the elevation of phosphate, parathyroid hormone (PTH) and alkaline phosphatase was 2-, 3- and 8-fold in this stage, respectively. Conclusion Elevated FGF23 levels may have a strong correlation with the disease pathogenesis. In addition, FGF23 might be a future therapeutic target to intervene against the progression of CKD as well as to increase patient survivability. PMID:27194998

  8. Effects of elevated atmospheric CO2 concentration on leaf dark respiration of Xanthium strumarium in light and in darkness.

    PubMed

    Wang, X; Lewis, J D; Tissue, D T; Seemann, J R; Griffin, K L

    2001-02-27

    Leaf dark respiration (R) is an important component of plant carbon balance, but the effects of rising atmospheric CO(2) on leaf R during illumination are largely unknown. We studied the effects of elevated CO(2) on leaf R in light (R(L)) and in darkness (R(D)) in Xanthium strumarium at different developmental stages. Leaf R(L) was estimated by using the Kok method, whereas leaf R(D) was measured as the rate of CO(2) efflux at zero light. Leaf R(L) and R(D) were significantly higher at elevated than at ambient CO(2) throughout the growing period. Elevated CO(2) increased the ratio of leaf R(L) to net photosynthesis at saturated light (A(max)) when plants were young and also after flowering, but the ratio of leaf R(D) to A(max) was unaffected by CO(2) levels. Leaf R(N) was significantly higher at the beginning but significantly lower at the end of the growing period in elevated CO(2)-grown plants. The ratio of leaf R(L) to R(D) was used to estimate the effect of light on leaf R during the day. We found that light inhibited leaf R at both CO(2) concentrations but to a lesser degree for elevated (17-24%) than for ambient (29-35%) CO(2)-grown plants, presumably because elevated CO(2)-grown plants had a higher demand for energy and carbon skeletons than ambient CO(2)-grown plants in light. Our results suggest that using the CO(2) efflux rate, determined by shading leaves during the day, as a measure for leaf R is likely to underestimate carbon loss from elevated CO(2)-grown plants. PMID:11226264

  9. Effects of acupuncture stimulation on blood glucose concentration in the Otsuka Long-Evans Tokushima Fatty (OLETF) rat, an animal model for type-2 diabetes mellitus

    PubMed Central

    Nakamura, Hironori; Ishigami, Tatsuyo; Kawase, Yosihyuki; Yamada, Atsushi; Minagawa, Munenori; Fukuta, Hiroyasu; Kurono, Yasuzo; Suzuki, Hikaru

    2014-01-01

    Background Effects of acupuncture stimulation on blood glucose concentration and body weight were investigated in the Otsuka Long-Evans Tokushima Fatty (OLETF) rat, a model for type-2 diabetes. Material/Methods Three groups of rats were used: OLETF, acupuncture-treated OLETF (AcOLETF), and Long-Evans Tokushima Otsuka (LETO) rats (as control for the OLETF rats). In AcOLETF rats, acupuncture stimulation was applied twice a week to 6 points (zhongwan, tianshu, qihai, ganshu, pishu, shenshu) and changes in blood glucose concentration and body weight were measured. Results Initially, at 6 weeks old, there was no significant difference in blood glucose levels between groups. Blood glucose levels increased with age in each group, reaching a maximum of about 430 mg/dl at 37 weeks in OLETF rats. In AcOLETF rats, blood glucose levels increased at a slower rate than in OLETF rats, reaching a maximum concentration of about 280 mg/dl at 37 weeks of age, significantly lower than that in OLETF rats. The concentration of blood glucose in LETO rats had stabilized at a maximum value of 120~140 mg/dl by 16 weeks, remaining at this level for up to 39 weeks. In each group, body weight increased with age and was not affected by acupuncture treatment. Conclusions In OLETF rats, acupuncture treatment significantly reduced blood glucose levels, but not their body weight, suggesting that acupuncture therapy was effective in preventing the development of type-2 diabetes mellitus. PMID:24841896

  10. Myocardial infarction, ST-elevation and non-ST-elevation myocardial infarction and modelled daily pollution concentrations: a case-crossover analysis of MINAP data

    PubMed Central

    Butland, Barbara K; Atkinson, Richard W; Milojevic, Ai; Heal, Mathew R; Doherty, Ruth M; Armstrong, Ben G; MacKenzie, Ian A; Vieno, Massimo; Lin, Chun; Wilkinson, Paul

    2016-01-01

    Objectives To investigate associations between daily concentrations of air pollution and myocardial infarction (MI), ST-elevation MI (STEMI) and non-ST-elevation MI (NSTEMI). Methods Modelled daily ground-level gaseous, total and speciated particulate pollutant concentrations and ground-level daily mean temperature, all at 5 km×5 km horizontal resolution, were linked to 202 550 STEMI and 322 198 NSTEMI events recorded on the England and Wales Myocardial Ischaemia National Audit Project (MINAP) database. The study period was 2003–2010. A case-crossover design was used, stratified by year, month and day of the week. Data were analysed using conditional logistic regression, with pollutants modelled as unconstrained distributed lags 0–2 days. Results are presented as percentage change in risk per 10 µg/m3 increase in the pollutant relevant metric, having adjusted for daily mean temperature, public holidays, weekly influenza consultation rates and a sine-cosine annual cycle. Results There was no evidence of an association between MI or STEMI and any of O3, NO2, PM2.5, PM10 or selected PM2.5 components (sulfate and elemental carbon). For NSTEMI, there was a positive association with daily maximum 1-hour NO2 (0.27% (95% CI 0.01% to 0.54%)), which persisted following adjustment for O3 and adjustment for PM2.5. The association appeared to be confined to the midland and southern regions of England and Wales. Conclusions The study found no evidence of an association between the modelled pollutants (including components) investigated and STEMI but did find some evidence of a positive association between NO2 and NSTEMI. Confirmation of this association in other studies is required. PMID:27621827

  11. Diurnal and elevational variations in ozone and aerosol concentrations in New Hampshire`s Class-I Airsheds

    SciTech Connect

    Hill, L.B.; Allen, G.A.

    1994-12-31

    Ozone and fine mass aerosol concentrations on New Hampshire`s Mount Washington, situated adjacent to both the Presidential/Dry River and Great Gulf Wilderness Class-I Airsheds, exhibit distinct diurnal and elevational patterns. These patterns are attributed to regional pollutant transport dynamics, nocturnal atmospheric stratification, mountain meteorological phenomena and scavenging. A well-defined planetary boundary layer (PBL) forms at about 1 km elevation at night as demonstrated by nocturnal ozone monitoring along the Mount Washington Auto Road. The PBL provides an effective elevational barrier at night, isolating the valleys from the regionally transported air pollutants present above the mixing layer. During the daytime, the PBL breaks up due to convective processes and katabatic winds resulting from solar heating in the valley. This process creates a diurnal mixing cycle with ozone maxima recorded near mid-day in the adjacent valley. In contrast, fine mass concentrations are higher at the valley site, attributed to local source inputs, and the lack of strong nocturnal scavenging processes, compared with ozone. How aerosol concentrations are related to the PBL and how they are affected by diurnal mixing remains unclear largely due to current sampling methods. Exposure to ozone is generally greater above the treeline in the two airsheds.

  12. Lidocaine concentration in mandibular bone after subperiosteal infiltration anesthesia decreases with elevation of periosteal flap and irrigation with saline.

    PubMed

    Ogawa, Sachie; Watanabe, Masahiro; Kawaai, Hiroyoshi; Tada, Hitoshi; Yamazaki, Shinya

    2014-01-01

    It has been reported that the action of infiltration anesthesia on the jawbone is attenuated significantly by elevation of the periosteal flap with saline irrigation in clinical studies; however, the reason is unclear. Therefore, the lidocaine concentration in mandibular bone after subperiosteal infiltration anesthesia was measured under several surgical conditions. The subjects were 48 rabbits. Infiltration anesthesia by 0.5 mL of 2% lidocaine with 1 : 80,000 epinephrine (adrenaline) was injected into the right mandibular angle and left mandibular body, respectively. Under several surgical conditions (presence or absence of periosteal flap, and presence or absence of saline irrigation), both mandibular bone samples were removed at a fixed time after subperiosteal infiltration anesthesia. The lidocaine concentration in each mandibular bone sample was measured by high-performance liquid chromatography. As a result, elevation of the periosteal flap with saline irrigation significantly decreased the lidocaine concentration in the mandibular bone. It is suggested that the anesthetic in the bone was washed out by saline irrigation. Therefore, supplemental conduction and/or general anesthesia should be utilized for long operations that include elevation of the periosteal flap with saline irrigation. PMID:24932978

  13. Nonthyroidal Illness Syndrome in Cardiac Illness Involves Elevated Concentrations of 3,5-Diiodothyronine and Correlates with Atrial Remodeling

    PubMed Central

    Dietrich, Johannes W.; Müller, Patrick; Schiedat, Fabian; Schlömicher, Markus; Strauch, Justus; Chatzitomaris, Apostolos; Klein, Harald H.; Mügge, Andreas; Köhrle, Josef; Rijntjes, Eddy; Lehmphul, Ina

    2015-01-01

    Background Although hyperthyroidism predisposes to atrial fibrillation, previous trials have suggested decreased triiodothyronine (T3) concentrations to be associated with postoperative atrial fibrillation (POAF). Therapy with thyroid hormones (TH), however, did not reduce the risk of POAF. This study reevaluates the relation between thyroid hormone status, atrial electromechanical function and POAF. Methods Thirty-nine patients with sinus rhythm and no history of atrial fibrillation or thyroid disease undergoing cardiac surgery were prospectively enrolled. Serum concentrations of thyrotropin, free (F) and total (T) thyroxine (T4) and T3, reverse (r)T3, 3-iodothyronamine (3-T1AM) and 3,5-diiodothyronine (3,5-T2) were measured preoperatively, complemented by evaluation of echocardiographic and electrophysiological parameters of cardiac function. Holter-ECG and telemetry were used to screen for POAF for 10 days following cardiac surgery. Results Seven of 17 patients who developed POAF demonstrated nonthyroidal illness syndrome (NTIS; defined as low T3 and/or low T4 syndrome), compared to 2 of 22 (p < 0.05) patients who maintained sinus rhythm. In patients with POAF, serum FT3 concentrations were significantly decreased, but still within their reference ranges. 3,5-T2 concentrations directly correlated with rT3 concentrations and inversely correlated with FT3 concentrations. Furthermore, 3,5-T2 concentrations were significantly elevated in patients with NTIS and in subjects who eventually developed POAF. In multivariable logistic regression FT3, 3,5-T2, total atrial conduction time, left atrial volume index and Fas ligand were independent predictors of POAF. Conclusion This study confirms reduced FT3 concentrations in patients with POAF and is the first to report on elevated 3,5-T2 concentrations in cardiac NTIS. The pathogenesis of NTIS therefore seems to involve more differentiated allostatic mechanisms. PMID:26279999

  14. Elevated CO2 concentration increase the mobility of Cd and Zn in the rhizosphere of hyperaccumulator Sedum alfredii.

    PubMed

    Li, Tingqiang; Tao, Qi; Liang, Chengfeng; Yang, Xiaoe

    2014-05-01

    The effects of elevated CO2 on metal species and mobility in the rhizosphere of hyperaccumulator are not well understood. We report an experiment designed to compare the effects of elevated CO2 on Cd/Zn speciation and mobility in the rhizosphere of hyperaccumulating ecotype (HE) and a non-hyperaccumulating ecotype (NHE) of Sedum alfredii grown under ambient (350 μl l(-1)) or elevated (800 μl l(-1)) CO2 conditions. No difference in solution pH of NHE was observed between ambient and elevated CO2 treatments. For HE, however, elevated CO2 reduced soil solution pH by 0.22 unit, as compared to ambient CO2 conditions. Elevated CO2 increased dissolved organic carbon (DOC) and organic acid levels in soil solution of both ecotypes, but the increase in HE solution was much greater than in NHE solution. After the growth of HE, the concentrations of Cd and Zn in soil solution decreased significantly regardless of CO2 level. The visual MINTEQ speciation model predicted that Cd/Zn-DOM complexes were the dominant species in soil solutions, followed by free Cd(2+) and Zn(2+) species for both ecotypes. However, Cd/Zn-DOM complexes fraction in soil solution of HE was increased by the elevated CO2 treatment (by 8.01 % for Cd and 8.47 % for Zn, respectively). Resin equilibration experiment results indicated that DOM derived from the rhizosphere of HE under elevated CO2 (HE-DOM-E) (90 % for Cd and 73 % for Zn, respectively) showed greater ability to form complexes with Cd and Zn than those under ambient CO2 (HE-DOM-A) (82 % for Cd and 61 % for Zn, respectively) in the undiluted sample. HE-DOM-E showed greater ability to extract Cd and Zn from soil than HE-DOM-A. It was concluded that elevated CO2 could increase the mobility of Cd and Zn due to the enhanced formation of DOM-metal complexes in the rhizosphere of HE S. alfredii. PMID:24453019

  15. Loss of function of PTEN alters the relationship between glucose concentration and cell proliferation, increases glycolysis, and sensitizes cells to 2-deoxyglucose.

    PubMed

    Blouin, Marie-José; Zhao, Yunhua; Zakikhani, Mahvash; Algire, Carolyn; Piura, Esther; Pollak, Michael

    2010-03-28

    PTEN loss of function enhances proliferation, but effects on cellular energy metabolism are less well characterized. We used an inducible PTEN expression vector in a PTEN-null glioma cell line to examine this issue. While proliferation of PTEN-positive cells was insensitive to increases in glucose concentration beyond 2.5mM, PTEN-null cells significantly increased proliferation with increasing glucose concentration across the normal physiologic range to approximately 10mM, coinciding with a shift to glycolysis and "glucose addiction". This demonstrates that the impact of loss of function of PTEN is modified by glucose concentration, and may be relevant to epidemiologic results linking hyperglycemia to cancer risk and cancer mortality. PMID:19744772

  16. Selenium accumulation and selenium tolerance of salt grass from soils with elevated concentrations of Se and salinity

    SciTech Connect

    Wu, L.; Huang, Z.Z. )

    1991-12-01

    Biomass production, selenium accumulation, and the role of the bioextraction of selenium by salt grass (Distichlis spicata L.) in soils with elevated concentrations of Se and salinity at Kesterson, California, were studied. Salt grass contributed more than 80% vegetative coverage and 90% dry weight in the grassland communities where the soil Se concentrations were 100 times (1000 to 3000 micrograms kg-1) higher than the Se concentrations found in soils of the control sites. No evidence for evolution of Se tolerance was found in the salt grass populations. The successful colonization of salt grass in the soil with elevated Se and salinity is attributable to the presence of high concentrations of soil sulfate. Salt grass accumulated less Se than other salt-tolerant plant species existing in the same area, and no predation of animals and insects on salt grass has been noticed. Salt grass can transpire substantial amounts of volatile Se through its plant tissue. Under field conditions, a 1-m2 salt grass plot may produce 180 micrograms volatile selenium per day. However, no reduction of soil Se concentration in the salt grass habitat was detected over a period of 1 year. A long-term monitoring of Se status is needed in order to make predictions of the effectiveness of efforts to clean up Se-contaminated soils through the use of native plant species.

  17. Selenium accumulation and selenium tolerance of salt grass from soils with elevated concentrations of Se and salinity.

    PubMed

    Wu, L; Huang, Z Z

    1991-12-01

    Biomass production, selenium accumulation, and the role of the bioextraction of selenium by salt grass (Distichlis spicata L.) in soils with elevated concentrations of Se and salinity at Kesterson, California, were studied. Salt grass contributed more than 80% vegetative coverage and 90% dry weight in the grassland communities where the soil Se concentrations were 100 times (1000 to 3000 micrograms kg-1) higher than the Se concentrations found in soils of the control sites. No evidence for evolution of Se tolerance was found in the salt grass populations. The successful colonization of salt grass in the soil with elevated Se and salinity is attributable to the presence of high concentrations of soil sulfate. Salt grass accumulated less Se than other salt-tolerant plant species existing in the same area, and no predation of animals and insects on salt grass has been noticed. Salt grass can transpire substantial amounts of volatile Se through its plant tissue. Under field conditions, a 1-m2 salt grass plot may produce 180 micrograms volatile selenium per day. However, no reduction of soil Se concentration in the salt grass habitat was detected over a period of 1 year. A long-term monitoring of Se status is needed in order to make predictions of the effectiveness of efforts to clean up Se-contaminated soils through the use of native plant species. PMID:1778115

  18. High glucose concentrations induce TNF-α production through the down-regulation of CD33 in primary human monocytes

    PubMed Central

    2012-01-01

    Background CD33 is a membrane receptor containing a lectin domain and a cytoplasmic immunoreceptor tyrosine-based inhibitory motif (ITIM) that is able to inhibit cytokine production. CD33 is expressed by monocytes, and reduced expression of CD33 correlates with augmented production of inflammatory cytokines, such as IL-1β, TNF-α, and IL-8. However, the role of CD33 in the inflammation associated with hyperglycemia and diabetes is unknown. Therefore, we studied CD33 expression and inflammatory cytokine secretion in freshly isolated monocytes from patients with type 2 diabetes. To evaluate the effects of hyperglycemia, monocytes from healthy donors were cultured with different glucose concentrations (15-50 mmol/l D-glucose), and CD33 expression and inflammatory cytokine production were assessed. The expression of suppressor of cytokine signaling protein-3 (SOCS-3) and the generation of reactive oxygen species (ROS) were also evaluated to address the cellular mechanisms involved in the down-regulation of CD33. Results CD33 expression was significantly decreased in monocytes from patients with type 2 diabetes, and higher levels of TNF-α, IL-8 and IL-12p70 were detected in the plasma of patients compared to healthy donors. Under high glucose conditions, CD33 protein and mRNA expression was significantly decreased, whereas spontaneous TNF-α secretion and SOCS-3 mRNA expression were increased in monocytes from healthy donors. Furthermore, the down-regulation of CD33 and increase in TNF-α production were prevented when monocytes were treated with the antioxidant α-tocopherol and cultured under high glucose conditions. Conclusion Our results suggest that hyperglycemia down-regulates CD33 expression and triggers the spontaneous secretion of TNF-α by peripheral monocytes. This phenomenon involves the generation of ROS and the up-regulation of SOCS-3. These observations support the importance of blood glucose control for maintaining innate immune function and suggest

  19. Comparison of a Point-of-Care Glucometer and a Laboratory Autoanalyzer for Measurement of Blood Glucose Concentrations in Domestic Pigeons ( Columba livia domestica).

    PubMed

    Mohsenzadeh, Mahdieh Sadat; Zaeemi, Mahdieh; Razmyar, Jamshid; Azizzadeh, Mohammad

    2015-09-01

    Biochemical analysis is necessary for diagnosis and monitoring of diseases in birds; however, the small volume of blood that can be safely obtained from small avian species often limits laboratory diagnostic testing. Consequently, a suitable methodology requiring only a small volume of blood must be used. This study was designed to compare blood glucose concentrations in domestic pigeons ( Columba livia domestica) as measured by a commercial, handheld, human glucometer and a standard autoanalyzer. During the first phase of the study, whole blood samples obtained from 30 domestic pigeons were used to measure the blood glucose concentration with a glucometer, the packed cell volume (PCV), and the total erythrocyte count (nRBC). Plasma separated from the each sample was then used to obtain the plasma glucose concentration with the autoanalyzer. During the second phase of the study, 30 pigeons were assigned to 2 equal groups (n = 15). Hypoglycemia or hyperglycemia was induced in each group by intravenous injection of insulin or glucose, respectively. Blood was collected and processed, and glucose concentrations, PCV, and nRBC were measured as previously described. Linear-regression models demonstrated a significant relationship between results measured by the glucometer and autoanalyzer results from normoglycemic (correlation coefficient [R] = 0.43, P = .02), hypoglycemic (R = 0.95; P < .001), and hyperglycemic (R = 0.81; P < .001) birds. The results of this study suggest that we can predict the real blood-glucose concentration of pigeons by using results obtained by a glucometer. PMID:26378663

  20. Interactive Effects of Elevated CO2 Concentration and Irrigation on Photosynthetic Parameters and Yield of Maize in Northeast China

    PubMed Central

    Meng, Fanchao; Zhang, Jiahua; Yao, Fengmei; Hao, Cui

    2014-01-01

    Maize is one of the major cultivated crops of China, having a central role in ensuring the food security of the country. There has been a significant increase in studies of maize under interactive effects of elevated CO2 concentration ([CO2]) and other factors, yet the interactive effects of elevated [CO2] and increasing precipitation on maize has remained unclear. In this study, a manipulative experiment in Jinzhou, Liaoning province, Northeast China was performed so as to obtain reliable results concerning the later effects. The Open Top Chambers (OTCs) experiment was designed to control contrasting [CO2] i.e., 390, 450 and 550 µmol·mol−1, and the experiment with 15% increasing precipitation levels was also set based on the average monthly precipitation of 5–9 month from 1981 to 2010 and controlled by irrigation. Thus, six treatments, i.e. C550W+15%, C550W0, C450W+15%, C450W0, C390W+15% and C390W0 were included in this study. The results showed that the irrigation under elevated [CO2] levels increased the leaf net photosynthetic rate (Pn) and intercellular CO2 concentration (Ci) of maize. Similarly, the stomatal conductance (Gs) and transpiration rate (Tr) decreased with elevated [CO2], but irrigation have a positive effect on increased of them at each [CO2] level, resulting in the water use efficiency (WUE) higher in natural precipitation treatment than irrigation treatment at elevated [CO2] levels. Irradiance-response parameters, e.g., maximum net photosynthetic rate (Pnmax) and light saturation points (LSP) were increased under elevated [CO2] and irrigation, and dark respiration (Rd) was increased as well. The growth characteristics, e.g., plant height, leaf area and aboveground biomass were enhanced, resulting in an improved of yield and ear characteristics except axle diameter. The study concluded by reporting that, future elevated [CO2] may favor to maize when coupled with increasing amount of precipitation in Northeast China. PMID:24848097

  1. Interactive effects of elevated CO2 concentration and irrigation on photosynthetic parameters and yield of maize in Northeast China.

    PubMed

    Meng, Fanchao; Zhang, Jiahua; Yao, Fengmei; Hao, Cui

    2014-01-01

    Maize is one of the major cultivated crops of China, having a central role in ensuring the food security of the country. There has been a significant increase in studies of maize under interactive effects of elevated CO2 concentration ([CO2]) and other factors, yet the interactive effects of elevated [CO2] and increasing precipitation on maize has remained unclear. In this study, a manipulative experiment in Jinzhou, Liaoning province, Northeast China was performed so as to obtain reliable results concerning the later effects. The Open Top Chambers (OTCs) experiment was designed to control contrasting [CO2] i.e., 390, 450 and 550 µmol·mol(-1), and the experiment with 15% increasing precipitation levels was also set based on the average monthly precipitation of 5-9 month from 1981 to 2010 and controlled by irrigation. Thus, six treatments, i.e. C550W+15%, C550W0, C450W+15%, C450W0, C390W+15% and C390W0 were included in this study. The results showed that the irrigation under elevated [CO2] levels increased the leaf net photosynthetic rate (Pn) and intercellular CO2 concentration (Ci) of maize. Similarly, the stomatal conductance (Gs) and transpiration rate (Tr) decreased with elevated [CO2], but irrigation have a positive effect on increased of them at each [CO2] level, resulting in the water use efficiency (WUE) higher in natural precipitation treatment than irrigation treatment at elevated [CO2] levels. Irradiance-response parameters, e.g., maximum net photosynthetic rate (Pnmax) and light saturation points (LSP) were increased under elevated [CO2] and irrigation, and dark respiration (Rd) was increased as well. The growth characteristics, e.g., plant height, leaf area and aboveground biomass were enhanced, resulting in an improved of yield and ear characteristics except axle diameter. The study concluded by reporting that, future elevated [CO2] may favor to maize when coupled with increasing amount of precipitation in Northeast China. PMID:24848097

  2. Does an elevated CO2 concentration decrease dark respiration in trees? Final technical report

    SciTech Connect

    Long, Stephen

    2003-12-31

    Averaged across many previous investigations, doubling the CO2 concentration ([CO2]) has frequently been reported to cause an instantaneous reduction of leaf dark respiration measured as CO2 efflux. No known mechanism accounts for this effect. While four recent studies have shown that the measurement of respiratory CO2 efflux is prone to experimental artifacts that could account for the reported response, papers published since the start of the current research continue to report an instantaneous depression of respiratory CO2 efflux by elevation of [CO2]. Here, these artifacts are avoided by use of a high-resolution dual channel oxygen analyzer within an open gas exchange system to measure respiratory 02 uptake in normal air. Leaf 02 uptake was determined in response to instantaneous elevation of [CO2] in nine contrasting species and to long-term elevation in seven species from four of the DOE-sponsored long-term elevated [CO2] field experiments. Over one thousand separate measurements of respiration failed to reveal any decrease in respiratory 02 uptake with an instantaneous increase in [CO2]. Respiration was found insensitive not only to doubling [CO2], but also to a five-fold increase and to decrease to zero.

  3. Elevated formic acid concentrations in putrefied post-mortem blood and urine samples.

    PubMed

    Viinamäki, Jenni; Rasanen, Ilpo; Vuori, Erkki; Ojanperä, Ilkka

    2011-05-20

    Formic acid (FA) concentration was measured in post-mortem blood and urine samples as methyl formate using a headspace in-tube extraction gas-chromatography-mass-spectrometry method. A total of 113 cases were analyzed, each including a blood and urine sample fortified with 1% sodium fluoride. The cases were divided into three groups: regular (n=59), putrefied (n=30), and methanol-positive (n=22) cases. There was no evidence of ante-mortem methanol consumption in the regular and putrefied cases. In regular cases, the mean (and median) FA concentrations were 0.04 g/l (0.04 g/l) and 0.06 g/l (0.04 g/l) in blood and urine, respectively. In putrefied cases, the mean (and median) FA concentrations were substantially higher, 0.24 g/l (0.22 g/l) and 0.25 g/l (0.15 g/l) in blood and urine, respectively. In three putrefied cases, FA concentration in blood exceeded 0.5 g/l, a level associated with fatal methanol poisoning. Ten putrefied cases were reanalyzed after 3-4 months storage, and no significant changes in FA concentrations were seen. These observations suggest that FA was formed by putrefaction during the post-mortem period, not during sample storage when sodium fluoride was added as a preservative. In methanol-positive cases, the mean (and median) FA concentrations were 0.80 g/l (0.88 g/l) and 3.4 g/l (3.3 g/l) in blood and urine, respectively, and the concentrations ranged from 0.19 to 1.0 g/l in blood and from 1.7 to 5.6 g/l in urine. The mean (and median) methanol concentrations in methanol-positive cases were 3.0 g/l (3.0 g/l) and 4.4 g/l (4.7 g/l) in blood and in urine, respectively. The highest methanol concentrations were 6.0 g/l and 8.7 g/l in blood and urine, respectively. No ethyl alcohol was found in the methanol-positive blood samples. Poor correlation was shown between blood and urine concentrations of FA. Poor correlations were also shown, in both blood and urine, between methanol and FA concentrations. PMID:21112705

  4. Elevated pCO2 effects on the geochemistry of carbonate aquifers: calcite dissolution as a driver of elevated metal concentrations

    NASA Astrophysics Data System (ADS)

    Wunsch, A.; Navarre-Sitchler, A. K.; Moore, J.; McCray, J. E.

    2012-12-01

    Geological carbon capture, utilization and storage has gained momentum in the last decade as a viable option of reducing anthropogenic emissions of CO2, with several demonstration projects completed, in progress or planned for upcoming years. However, large-scale CO2-injection operations are accompanied by concerns of CO2 leakage from deep geological repositories and subsequent contact with shallower aquifers, such as underground sources of drinking water. Direct toxicity of CO2 is of lesser concern; rather, it is the acidification of aquifers from increased CO2 partial-pressures (pCO2), which may lead to release of metals into groundwater through mineral dissolution and metal desorption. Previous geochemical studies have suggested that the presence of calcite in aquifer material would reduce the hazard of metal release by effectively buffering acidity via calcite dissolution at elevated pCO2, thus placing carbonate aquifers at lesser risk in case of CO2 leakage. Yet calcite is rarely found in pure form, and often contains a wide range of impurities, including metals such as As, Cr, and Pb, in solid-solution. Dissolution of calcite during acidity buffering is accompanied by release of these impurities from the calcite lattice. We show through experimental work that dissolution of calcite is the primary mechanism responsible for elevated concentrations of metals in carbonate aquifers at high pCO2. It is also evident that the mechanism responsible for metal release, i.e. dissolution or desorption, is metal-specific and pCO2-specific. Modeling work based on our experimental results suggests that in reducing aquifers calcite can contribute more to release of metals than sulfides, which are generally viewed as likely sources of metals in aquifers, during a hypothetical 30-year CO2 leak. In addition, modeling work suggests that when sulfide minerals are present in a carbonate aquifer, metals release would be more sensitive to pO2 than to pCO2.

  5. Combined effects of elevated temperature and CO2 concentration on Cd and Zn accumulation dynamics in Triticum aestivum L.

    PubMed

    Wang, Xiaoheng; Li, Yu; Lu, Hong; Wang, Shigong

    2016-09-01

    A simulated climate warming experiment was conducted to evaluate the combined effects of elevated temperature and CO2 concentration on the bioaccumulation, translocation and subcellular distributions of Cd and Zn in wheat seedlings (Triticum aestivum L. cv. Xihan 1.) at Dingxi, Gansu Province, China. The objective was to find evidence that global climate change is affecting the bioaccumulation of Cd and Zn in T. aestivum L. cv. Xihan 1. The results showed that compared to control A, elevated temperature and CO2 increased Cd bioaccumulation in the shoots by 1.4-2.5 times, and increased that in the roots by 1.2-1.5 times, but decreased Zn levels in wheat shoots by 1.4-2.0 times, while decreased that in the roots by 1.6-1.9 times. Moreover, temperature and CO2 concentration increase also led to increased Cd concentration, and decreased Zn concentration in subcellular compartments of wheat seedlings. The largest Cd concentration increase (174.4%) was observed in the cell wall and debris fractions of shoots after they were subjected to the highest CO2 and temperature treatment (TC3). The largest Zn concentration decrease (53.1%) was observed in the soluble (F3) fractions of shoots after they were subjected to the medium CO2 and temperature treatment (TC2). The temperature and CO2 increase had no significant effect on the proportional distribution of Cd and Zn in the subcellular fractions. The root-to-shoot translocation of Cd increased with the increasing temperature and CO2 concentration. However, the Zn distributions only fluctuated within a small range. PMID:27593278

  6. Dietary patterns and risk of elevated C-reactive protein concentrations 12 years later.

    PubMed

    Julia, Chantal; Meunier, Nathalie; Touvier, Mathilde; Ahluwalia, Namanjeet; Sapin, Vincent; Papet, Isabelle; Cano, Noël; Hercberg, Serge; Galan, Pilar; Kesse-Guyot, Emmanuelle

    2013-08-01

    Inflammation mediates several chronic diseases. Micronutrients can act on inflammation, either through modulating cytokine production or by scavenging by-products of activated white cells. Identifying dietary patterns (DP) reflecting these mechanisms and relating them to inflammation is of interest. The objective of the study was to identify DP specifically associated with intakes of nutrients potentially involved in inflammatory processes in a middle-aged population and investigate long-term associations between these DP and C-reactive protein (CRP) status assessed several years later. Subjects included in the Supplementation in Vitamins and Mineral Antioxidants 2 cohort study, having available data on dietary assessment carried out in 1994-5 and CRP measurement in 2007-9, were included in the analysis. DP were extracted with reduced rank regression (RRR), using antioxidant micronutrients and PUFA as response variables. Associations between CRP measurements >3 mg/l and extracted DP were then examined with logistic regression models providing OR and 95% CI. A total of 2031 subjects (53·2% women, mean follow-up duration: 12·5 years) were included in the analyses. Of the four extracted DP, a DP with high loading values of vegetables and vegetable oils, leading to high intakes of antioxidant micronutrients and essential fatty acids, was significantly and negatively associated with risk of elevated CRP (OR 0·88; 95% CI 0·78, 0·98). Conversely, a DP reflecting a high n-6:n-3 fatty acid intake ratio was positively and significantly associated with elevated CRP (adjusted OR 1·15; 95% CI 1·00, 1·32). DP extracted with RRR provide support for further exploration of relationships between dietary behaviour and inflammation. PMID:23302662

  7. Lethal and sub-lethal effects of elevated CO2 concentrations on marine benthic invertebrates and fish.

    PubMed

    Lee, Changkeun; Hong, Seongjin; Kwon, Bong-Oh; Lee, Jung-Ho; Ryu, Jongseong; Park, Young-Gyu; Kang, Seong-Gil; Khim, Jong Seong

    2016-08-01

    Concern about leakage of carbon dioxide (CO2) from deep-sea storage in geological reservoirs is increasing because of its possible adverse effects on marine organisms locally or at nearby coastal areas both in sediment and water column. In the present study, we examined how elevated CO2 affects various intertidal epibenthic (benthic copepod), intertidal endobenthic (Manila clam and Venus clam), sub-tidal benthic (brittle starfish), and free-living (marine medaka) organisms in areas expected to be impacted by leakage. Acute lethal and sub-lethal effects were detected in the adult stage of all test organisms exposed to varying concentrations of CO2, due to the associated decline in pH (8.3 to 5.2) during 96-h exposure. However, intertidal organisms (such as benthic copepods and clams) showed remarkable resistance to elevated CO2, with the Venus clam being the most tolerant (LpH50 = 5.45). Sub-tidal species (such as brittle starfish [LpH50 = 6.16] and marine medaka [LpH50 = 5.91]) were more sensitive to elevated CO2 compared to intertidal species, possibly because they have fewer defensive capabilities. Of note, the exposure duration might regulate the degree of acute sub-lethal effects, as evidenced by the Venus clam, which showed a time-dependent effect to elevated CO2. Finally, copper was chosen as a model toxic element to find out the synergistic or antagonistic effects between ocean acidification and metal pollution. Combination of CO2 and Cu exposure enhances the adverse effects to organisms, generally supporting a synergistic effect scenario. Overall, the significant variation in the degree to which CO2 adversely affected organisms (viz., working range and strength) was clearly observed, supporting the general concept of species-dependent effects of elevated CO2. PMID:27074931

  8. Equilibrium concentrations of N2H4 and its decomposition products at elevated temperatures and pressures

    NASA Technical Reports Server (NTRS)

    Smetana, F. O.; Fairchild, H. N., III; Martin, G. L.

    1973-01-01

    Liquid hydrazine is considered as a convenient source of hydrogen rather than just as a rocket fuel. For such purposes, the hydrogen is usually obtained by passing the hydrazine through a heated catalytic bed. One convenient measure of the effectiveness of a catalytic decomposition device as a whole is to compare the quantity of hydrogen produced with the equilibrium concentration of the gaseous species N2H4, NH3, N3, and H2 which would exist at the temperature and pressure found in various parts of the device. Calculations of the concentrations were carried out and are reported here. Following presentation of the results in both tabular and graphical forms is a comparison between the computed equilibrium concentrations and available experimental data.

  9. Ablation of neurons expressing melanin-concentrating hormone (MCH) in adult mice improves glucose tolerance independent of MCH signaling.

    PubMed

    Whiddon, Benjamin B; Palmiter, Richard D

    2013-01-30

    Melanin-concentrating hormone (MCH)-expressing neurons have been ascribed many roles based on studies of MCH-deficient mice. However, MCH neurons express other neurotransmitters, including GABA, nesfatin, and cocaine-amphetamine-regulated transcript. The importance of these other signaling molecules made by MCH neurons remains incompletely characterized. To determine the roles of MCH neurons in vivo, we targeted expression of the human diphtheria toxin receptor (DTR) to the gene for MCH (Pmch). Within 2 weeks of diphtheria toxin injection, heterozygous Pmch(DTR/+) mice lost 98% of their MCH neurons. These mice became lean but ate normally and were hyperactive, especially during a fast. They also responded abnormally to psychostimulants. For these phenotypes, ablation of MCH neurons recapitulated knock-out of MCH, so MCH appears to be the critical neuromodulator released by these neurons. In contrast, MCH-neuron-ablated mice showed improved glucose tolerance when compared with MCH-deficient mutant mice and wild-type mice. We conclude that MCH neurons regulate glucose tolerance through signaling molecules other than MCH. PMID:23365238

  10. A SIMPLE TECHNIQUE FOR DETERMINING THE MAXIMUM GROUND LEVEL CONCENTRATION OF AN ELEVATED GASEOUS RELEASE

    EPA Science Inventory

    The paper describes the development of a screening technique to determine the maximum 1 hour ground level concentration of a gaseous emission from a stack located in flat terrain. The method does not require the use of a computer and eliminates the usual trial and error calculati...

  11. Changes in volatile compounds in whey protein concentrate stored at elevated temperature and humidity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Whey protein concentrate (WPC) has been recommended for use in emergency aid programs, but it is often stored overseas without temperature and relative humidity (RH) control, which may cause it to be rejected because of yellowing, off-flavors, or clumping. Therefore, the volatile compounds present ...

  12. Belowground grassland herbivores are resistant to elevated atmospheric CO2 concentrations in grassland ecosystems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Grasslands are considered to be one of the most sensitive ecosystems to rising atmospheric CO2 concentrations. Moreover, grasslands support large populations of belowground herbivores that consume a major portion of plant biomass. The direct trophic link between herbivores and plants suggests that...

  13. Elevated Circulating Sclerostin Concentrations in Individuals With High Bone Mass, With and Without LRP5 Mutations

    PubMed Central

    Poole, Kenneth E. S.; McCloskey, Eugene V.; Duncan, Emma L.; Rittweger, Jörn; Fraser, William D.; Smith, George Davey; Tobias, Jonathan H.

    2014-01-01

    Context: The role and importance of circulating sclerostin is poorly understood. High bone mass (HBM) caused by activating LRP5 mutations has been reported to be associated with increased plasma sclerostin concentrations; whether the same applies to HBM due to other causes is unknown. Objective: Our objective was to determine circulating sclerostin concentrations in HBM. Design and Participants: In this case-control study, 406 HBM index cases were identified by screening dual-energy x-ray absorptiometry (DXA) databases from 4 United Kingdom centers (n = 219 088), excluding significant osteoarthritis/artifact. Controls comprised unaffected relatives and spouses. Main measures: Plasma sclerostin; lumbar spine L1, total hip, and total body DXA; and radial and tibial peripheral quantitative computed tomography (subgroup only) were evaluated. Results: Sclerostin concentrations were significantly higher in both LRP5 HBM and non-LRP5 HBM cases compared with controls: mean (SD) 130.1 (61.7) and 88.0 (39.3) vs 66.4 (32.3) pmol/L (both P < .001, which persisted after adjustment for a priori confounders). In combined adjusted analyses of cases and controls, sclerostin concentrations were positively related to all bone parameters found to be increased in HBM cases (ie, L1, total hip, and total body DXA bone mineral density and radial/tibial cortical area, cortical bone mineral density, and trabecular density). Although these relationships were broadly equivalent in HBM cases and controls, there was some evidence that associations between sclerostin and trabecular phenotypes were stronger in HBM cases, particularly for radial trabecular density (interaction P < .01). Conclusions: Circulating plasma sclerostin concentrations are increased in both LRP5 and non-LRP5 HBM compared with controls. In addition to the general positive relationship between sclerostin and DXA/peripheral quantitative computed tomography parameters, genetic factors predisposing to HBM may contribute to

  14. Glucose metabolism in diabetic blood vessels

    SciTech Connect

    Brown, B.J.; Crass, M.F. III

    1986-03-05

    Since glycolysis appears to be coupled to active ion transport in vascular smooth muscle, alterations in glucose metabolism may contribute to cellular dysfunction and angiopathy in diabetes. Uptake and utilization of glucose were studied in perfused blood vessels in which pulsatile flow and perfusion pressure were similar to those measured directly in vivo. Thoracic aortae isolated from 8-wk alloxan diabetic (D) and nondiabetic control rabbits were cannulated, tethered, and perfused with oxygenated buffer containing 7 or 25 mM glucose and tracer amounts of glucose-U/sup -14/ C. Norepinephrine (NE) (10/sup -6/ M) and/or insulin (I) (150 ..mu..U/ml) and albumin (0.2%) were added. NE-induced tension development increased glucose uptake 39% and /sup 14/CO/sub 2/ and lactate production 2.3-fold. With 7 mM glucose, marked decreases in glucose uptake (74%), /sup 14/CO/sub 2/ (68%), lactate (30%), total tissue glycogen (75%), and tissue phospholipids (70%) were observed in D. Addition of I or elevation of exogenous glucose to 25 mM normalized glucose uptake, but had differential effects on the pattern of substrate utilization. Thus, in D, there was a marked depression of vascular glucose metabolism that was partially reversed by addition of low concentrations of insulin or D levels of glucose.

  15. [Effects of simulated elevation of atmospheric CO2 concentration on the physiological features of spring phytoplankton in Taihu Lake].

    PubMed

    Zhao, Xu-Hui; Tang, Long-Sheng; Shi, Xiao-Li; Yang, Zhou; Kong, Fan-Xiang

    2013-06-01

    To disclose the impact of different CO2 concentrations (270 x 10(-6), 380 x 10(-6), 750 x 10(-6)) on physiological features of spring phytoplankton, an in situ simulated experiment was carried out in Meiliang Bay of Taihu Lake from 29 April to 26 May in 2012. The results showed that atmospheric CO2 elevation would significantly alter the pH value and carbonate chemical environments of Taihu Lake, resulting in weakening the advantages of carbon concentrating mechanism (CCM) of phytoplankton. Phytoplankton in Taihu Lake tended to use more dissolved CO2 (CO2, aq) due to the deliberate CO2 sequestration under the high CO2 level treatment. When atmospheric CO2 concentration doubles at the end of century, the maximum growth rate constant of phytoplankton (U(max)), NPP, chlorophyll a (Chl-a)-specific NPP would increase by 63.1%, 69.6% and 33.8%, respectively. Atmospheric CO2 elevation promoted the maximum photosynthetic efficiency of chlorophyta and bacillariophyta in Taihu Lake and its promotion effect on bacillariophyta was more notable than that on chlorophyta. However, it did not change the photosynthetic efficiency of cyanobacteria which was very low in spring. Meanwhile, the stoichiometry value of phytoplankton changed significantly due to the CO2 elevation, as phytoplankton cells assimilated more C and N, but less P under the treatment of high CO2 level. Our results indicated the enhanced CO2 level could dramatically change the physiological features of phytoplankton. This information would help us to understand and predict the response of phytoplankton in Taihu Lake to the future climate change. PMID:23947023

  16. Highly stable concentrated nanoemulsions by the phase inversion composition method at elevated temperature.

    PubMed

    Yu, Lijie; Li, Chao; Xu, Jian; Hao, Jingcheng; Sun, Dejun

    2012-10-16

    Oil-in-water nanoemulsions were produced in the system water/Span 80-Tween 80/paraffin oil via the phase inversion composition (PIC) method at elevated temperature. With the increase of preparation temperature from 20 to 70 °C, we found that the emulsion droplet diameter decreases from 10.3 μm to 51 nm, proving the formation of nanoemulsions. The viscosity of nanoemulsions clearly increases with droplet volume fraction, φ, but the droplet size changes less. Significantly, at φ ≤ 0.5, the size distribution of nanoemulsions can be kept unchangeable more than 5 months. These results proved that the highly viscous paraffin oil can hardly be dispersed by the PIC method at 25 °C, but the increase in preparation temperature makes it possible for producing monodisperse nanoemulsions. Once the nanoemulsion is produced, the stability against Ostwald ripening is outstanding due to the extremely low solubility of the paraffin oil in the continuous phase. The highly stable nanoemulsions are of great importance in practical applications. PMID:22985401

  17. Influence of elevated ozone concentration on methanotrophic bacterial communities in soil under field condition

    NASA Astrophysics Data System (ADS)

    Huang, Y. Z.; Zhong, M.

    2015-05-01

    The open top chamber (OTC) method was used in combination with real-time quantitative PCR and terminal restriction fragment length polymorphism (T-RFLP) techniques in the wheat field to study the influence of different levels of O3 concentrations (ambient air filtered by activated carbons, 40 ppb, 80 ppb and 120 ppb) on the quantity and community structure of methanotrophic bacteria. O3 stress can influence the potential methane oxidation rate (PMOR) and potential methane production rate (PMPR) in the farmland soil. O3 treatment of 40 ppb improved significantly the 16S rRNA gene copy number in the total methanotrophic bacteria pmoA, and type I and type II methanotrophic bacteria in the soil depth of 0-20 cm. When the O3 concentration reached 120 ppb, the 16S rRNA gene copy number in the total methanotrophic bacteria pmoA and type I methanotrophic bacteria decreased significantly as compared to the control treatment in 10-20 cm layer. The 16s rRNA gene copy number of total methanotrophic bacteria pmoA and type I and type II methanotrophic bacteria were influenced by different O3 concentration and soil depth. The T-RFLP analysis indicated that O3 stress influenced significantly the community structure of the methanotrophic bacteria in soil, causing potential threat to the diversity of methanotrophic bacteria. It seems to imply that the rise of O3 concentration could produce an impact on the carbon cycling and the methane emission of the wheat field soil by changing the community structure and diversity of methanotrophic bacteria, which then influences the global climate change.

  18. Brain concentrations of benzodiazepines are elevated in an animal model of hepatic encephalopathy

    SciTech Connect

    Basile, A.S.; Pannell, L.; Jaouni, T.; Gammal, S.H.; Fales, H.M.; Jones, E.A.; Skolnick, P. )

    1990-07-01

    Brain extracts from rats with hepatic encephalopathy due to thioacetamide-induced fulminant hepatic failure contained 4- to 6-fold higher concentrations of substances that inhibit radioligand binding to benzodiazepine receptors than corresponding control rat extracts. Both isocratic and gradient-elution HPLC indicated that this inhibitory activity was localized in 3-8 peaks with retention times corresponding to deschlorodiazepam, deschlorolorazepam, lorazepam, oxazepam, diazepam, and N-desmethyldiazepam. The presence of diazepam and N-desmethyldiazepam was confirmed by mass spectroscopy. Both mass spectroscopic and radiometric techniques indicated that the concentrations of N-desmethyldiazepam and diazepam in brain extracts from encephalopathic rats were 2-9 and 5-7 times higher, respectively, than in control brain extracts. While benzodiazepines have been identified previously in mammalian and plant tissues, this report demonstrates that concentrations of these substances are increased in a pathophysiological condition. These findings provide a rational basis for the use of benzodiazepine receptor antagonists in the management of hepatic encephalopathy in humans.

  19. Elevating concentrations of capsaicin and dihydrocapsaicin in hot peppers using recycled waste.

    PubMed

    Antonious, George F

    2015-01-01

    Five Capsicum accessions (PI 435916 and PI 438614 from Capsicum chinense; PI 370004 and Grif 9354 from C. baccatum and PI 438649 from C. annuum) were selected from the U.S. Department of Agriculture-Agricultural Research Service Capsicum germplasm collection to study the impact of four soil management practices: yard waste (YW), sewage sludge (SS), chicken manure (CM) and no-mulch (NM) bare soil on fruit concentrations of capsaicin and dihydrocapsaicin, yield, plant size and mature fruit characteristics (fruit weight, length, width, and wall-thickness) of plants grown under these practices. Regardless of soil treatments, PI 438614 and PI 435916 contained the greatest concentrations of total capsaicinoids (capsaicin and dihydrocapsaicin). Fruits of plants grown in soil mixed with SS contained the greatest concentrations of total capsaicinoids. Fruits of plants grown in SS or CM contained the greatest fruit weight. PI 438649 produced the greatest fruit weight, length and wall-thickness. The total marketable yield expressed as weight of fruit plants was significantly higher in soils mixed with SS and CM compared to those mixed with YW and NM soils. PMID:25996816

  20. Identifying urban sources as cause of elevated grass pollen concentrations using GIS and remote sensing

    NASA Astrophysics Data System (ADS)

    Skjøth, C. A.; Ørby, P. V.; Becker, T.; Geels, C.; Schlünssen, V.; Sigsgaard, T.; Bønløkke, J. H.; Sommer, J.; Søgaard, P.; Hertel, O.

    2013-01-01

    We examine here the hypothesis that during flowering, the grass pollen concentrations at a specific site reflect the distribution of grass pollen sources within a few kilometres of this site. We perform this analysis on data from a measurement campaign in the city of Aarhus (Denmark) using three pollen traps and by comparing these observations with a novel inventory of grass pollen sources. The source inventory is based on a new methodology developed for urban-scale grass pollen sources. The new methodology is believed to be generally applicable for the European area, as it relies on commonly available remote sensing data combined with management information for local grass areas. The inventory has identified a number of grass pollen source areas present within the city domain. The comparison of the measured pollen concentrations with the inventory shows that the atmospheric concentrations of grass pollen in the urban zone reflect the source areas identified in the inventory, and that the pollen sources that are found to affect the pollen levels are located near or within the city domain. The results also show that during days with peak levels of pollen concentrations there is no correlation between the three urban traps and an operational trap located just 60 km away. This finding suggests that during intense flowering, the grass pollen concentration mirrors the local source distribution and is thus a local-scale phenomenon. Model simulations aimed at assessing population exposure to pollen levels are therefore recommended to take into account both local sources and local atmospheric transport, and not to rely only on describing regional to long-range transport of pollen. The derived pollen source inventory can be entered into local-scale atmospheric transport models in combination with other components that simulate pollen release in order to calculate urban-scale variations in the grass pollen load. The gridded inventory with a resolution of 14 m is therefore

  1. Identifying urban sources as cause to elevated grass pollen concentrations using GIS and remote sensing

    NASA Astrophysics Data System (ADS)

    Skjøth, C. A.; Ørby, P. V.; Becker, T.; Geels, C.; Schlünssen, V.; Sigsgaard, T.; Bønløkke, J. H.; Sommer, J.; Søgaard, P.; Hertel, O.

    2012-10-01

    We examine here the hypothesis that during flowering, the grass pollen concentrations at a specific site reflect the distribution of grass pollen sources within a few kilometres from this site. We perform this analysis on data from a measurement campaign in the city of Aarhus (Denmark) using three pollen traps and by comparing these observations with a novel inventory of grass pollen sources. The source inventory is based on a new methodology developed for urban scale grass pollen sources. The new methodology is believed to be generally applicable for the European area, as it relies on commonly available remote sensing data combined with management information for local grass areas. The inventory has identified a number of grass pollen source areas present within the city domain. The comparison of the measured pollen concentrations with the inventory shows that the atmospheric concentrations of grass pollen in the urban zone reflects the source areas identified in the inventory, and that these pollen sources that are found to affect the pollen levels are located near and within the city domain. The results also show that during days with peak levels of pollen concentrations, there is no correlation between the three urban traps and an operational trap located just 60 km away. This finding suggests that during intense flowering, the grass pollen concentration mirrors the local source distribution, and is thus a local scale phenomenon. Model simulations aiming at assessment of population exposure to pollen levels are therefore recommended to take into account both local sources and local atmospheric transport, and not rely only on describing regional to long-range transport of pollen. The derived pollen source inventory can be entered into local scale atmospheric transport models in combination with other components that simulates pollen release in order to calculate urban scale variations in the grass pollen load. The gridded inventory with a resolution of 14 m is

  2. Observation of Elevated Air Pollutant Concentrations in a Residential Neighborhood of Los Angeles California Using a Mobile Platform

    PubMed Central

    Hu, Shishan; Fruin, Scott; Kozawa, Kathleen; Mara, Steve; Winer, Arthur M.

    2013-01-01

    We observed elevated air pollutant concentrations, especially of ultrafine particles (UFP), black carbon (BC) and NO, across the residential neighborhood of the Boyle Heights Community (BH) of Los Angeles, California. Using an electric vehicle mobile platform equipped with fast response instruments, real-time air pollutant concentrations were measured in BH in spring and summer of 2008. Pollutant concentrations varied significantly in the two seasons, on different days, and by time of day, with an overall average UFP concentration in the residential areas of ~33 000 cm−3. The averaged UFP, BC, and NO concentrations measured on Soto St, a major surface street in BH, were 57 000 cm−3, 5.1 µg m−3, and 67 ppb, respectively. Concentrations of UFP across the residential areas in BH were nearly uniform spatially, in contrast to other areas in the greater metropolitan area of Los Angeles where UFP concentrations exhibit strong gradients downwind of roadways. We attribute this “UFP cloud” to high traffic volumes, including heavy duty diesel trucks on the freeways which surround and traverse BH, and substantial numbers of high-emitting vehicles (HEVs) on the surface streets traversing BH. Additionally, the high density of stop signs and lights and short block lengths, requiring frequent accelerations of vehicles, may contribute. The data also support a role for photochemical production of UFP in the afternoon. UFP concentration peaks (5 s average) of up to 9 million particles cm−3 were also observed immediately behind HEVs when they accelerated from stop lights in the BH neighborhood and areas immediately adjacent. Although encounters with HEV during mornings accounted for only about 6% and 17% of time spent monitoring residential areas and major surface streets, HEV contributed to about 28% and 53% of total ultrafine particles measured on the route, respectively. The observation of elevated pollutant number concentrations across the Boyle Heights community

  3. Observation of elevated air pollutant concentrations in a residential neighborhood of Los Angeles California using a mobile platform

    NASA Astrophysics Data System (ADS)

    Hu, Shishan; Paulson, Suzanne E.; Fruin, Scott; Kozawa, Kathleen; Mara, Steve; Winer, Arthur M.

    2012-05-01

    We observed elevated air pollutant concentrations, especially of ultrafine particles (UFP), black carbon (BC) and NO, across the residential neighborhood of the Boyle Heights Community (BH) of Los Angeles, California. Using an electric vehicle mobile platform equipped with fast response instruments, real-time air pollutant concentrations were measured in BH in spring and summer of 2008. Pollutant concentrations varied significantly in the two seasons, on different days, and by time of day, with an overall average UFP concentration in the residential areas of ∼33 000 cm-3. The averaged UFP, BC, and NO concentrations measured on Soto St, a major surface street in BH, were 57 000 cm-3, 5.1 μg m-3, and 67 ppb, respectively. Concentrations of UFP across the residential areas in BH were nearly uniform spatially, in contrast to other areas in the greater metropolitan area of Los Angeles where UFP concentrations exhibit strong gradients downwind of roadways. We attribute this “UFP cloud” to high traffic volumes, including heavy duty diesel trucks on the freeways which surround and traverse BH, and substantial numbers of high-emitting vehicles (HEVs) on the surface streets traversing BH. Additionally, the high density of stop signs and lights and short block lengths, requiring frequent accelerations of vehicles, may contribute. The data also support a role for photochemical production of UFP in the afternoon. UFP concentration peaks (5 s average) of up to 9 million particles cm-3 were also observed immediately behind HEVs when they accelerated from stop lights in the BH neighborhood and areas immediately adjacent. Although encounters with HEV during mornings accounted for only about 6% and 17% of time spent monitoring residential areas and major surface streets, HEV contributed to about 28% and 53% of total ultrafine particles measured on the route, respectively. The observation of elevated pollutant concentrations across the Boyle Heights community highlights

  4. Gluconeogenesis is not acutely regulated by either plasma glucose or plasma insulin concentration in parenterally fed ELBW infants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Parenterally fed ELBW infants often exhibit erratic regulation of plasma glucose levels in response to changes in glucose infusion rate. This apparent dysregulation could be the result of an inappropriate insulin secretory response, incomplete suppression of glucose production, or an inadequate chan...

  5. Tracing changes of N2O emission pathways in a permanent grassland under elevated atmospheric CO2 concentrations

    NASA Astrophysics Data System (ADS)

    Gorenflo, Andre; Moser, Gerald; Brenzinger, Kristof; Elias, Dafydd; McNamara, Neill; Clough, Tim; Maček, Irena; Vodnik, Dominik; Braker, Gesche; Schimmelpfennig, Sonja; Gerstner, Judith; Müller, Christoph

    2015-04-01

    The increase of greenhouse gases (GHG) in the atmosphere is of concern due to its effect on global temperatures. Nitrous oxide (N2O) with a Global Warming Potential of 298 over a 100 year period is of particular concern because strong feedback effects of elevated atmospheric CO2 on N2O emissions have been observed. However, so far the changes in processes which are responsible for such a feedback effect are only poorly understood. Our study was carried out in situ in a long-term Free Air Carbon dioxide Enrichment (FACE) study on permanent grassland at atmospheric CO2 concentrations 20% above ambient which expected at the middle of this century. We performed an in situ 15N tracing with differentially labelled NH4NO3 to trace the main N2O emission pathways. Over a period of more than one year we monitored at least weakly the N2O emissions with the closed chamber technique and analyzed the 15N signature of the N2O. The observed gaseous emissions under ambient and elevated atmospheric CO2 were associated with the observed gross N transformations and the microbial activities to identify the main emission pathways under ambient and elevated CO2.

  6. Elevated Carboxyhaemoglobin Concentrations by Pulse CO-Oximetry is Associated with Severe Aluminium Phosphide Poisoning.

    PubMed

    Mashayekhian, Mohammad; Hassanian-Moghaddam, Hossein; Rahimi, Mitra; Zamani, Nasim; Aghabiklooei, Abbas; Shadnia, Shahin

    2016-09-01

    In pulse CO-oximetry of aluminium phosphide (ALP)-poisoned patients, we discovered that carboxyhaemoglobin (CO-Hb) level was elevated. We aimed to determine whether a higher CO level was detected in patients with severe ALP poisoning and if this could be used as a prognostic factor in these patients. In a prospective case-control study, 96 suspected cases of ALP poisoning were evaluated. In the ALP-poisoned group, demographic characteristics, gastric and exhalation silver nitrate test results, average CO-Hb saturation, methaemoglobin saturation, and blood pressure and blood gas analysis until death/discharge were recorded. Severely poisoned patients were defined as those with systolic blood pressure ≤80 mmHg, pH ≤7.2, or HCO3 ≤15 meq/L or those who died, while patients with minor poisoning were those without any of these signs/symptoms. A control group (37 patients) was taken from other medically ill patients to detect probable effects of hypotension and metabolic acidosis on CO-Hb and methaemoglobin saturations. Of 96 patients, 27 died and 37 fulfilled the criteria for severe poisoning. All patients with carbon monoxide saturation >18% met the criteria to be included in the severe poisoning group and all with a SpCO >25% died. Concerning all significant variables in univariate analysis of severe ALP toxicity, the only significant variable which could independently predict death was carbon monoxide saturation. Due to high mortality rate and need for intensive care support, early prediction of outcome is vital for choosing an appropriate setting (ICU or ordinary ward). CO-oximetry is a good diagnostic and prognostic factor in patients with ALP poisoning even before any clinical evidence of toxicity will develop. PMID:26899262

  7. Elevated bronchoalveolar concentrations of MCP-1 in patients with pulmonary alveolar proteinosis.

    PubMed

    Iyonaga, K; Suga, M; Yamamoto, T; Ichiyasu, H; Miyakawa, H; Ando, M

    1999-08-01

    Pulmonary alveolar proteinosis (PAP) is a rare disease of unknown aetiology characterized by accumulations of lipoproteinaceous material within the alveoli. The alveolar macrophages become increasingly foamy, and are thought to have a role in the pathogenesis of PAP. However, the mechanisms of macrophage recruitment are unclear. In the bronchoalveolar lavage fluid (BALF) of four patients with PAP and 20 normal control subjects, the following were examined: the monocyte chemotactic activity due to the chemokine monocyte chemoattractant protein (MCP)-1 with the use of a chemotactic chamber assay, the levels of MCP-1 by enzyme-linked immunosorbent assay, and the MCP-1 expression on lavage cells by immunocytochemistry and in situ hybridization. The monocyte chemotactic activity in the BALF of the PAP patients was markedly elevated, and the activity was completely absorbed by treatment with anti-MCP-1. The MCP-1 levels in the BALF were surprisingly high in the PAP group (25,100+/-472 pg x mL(-1)), whereas low levels of MCP-1 were detected in the normal control subjects (mean: never smokers 4.8; smokers 10.4 pg x mL(-1)). MCP-1 protein and messenger ribonucleic acid were expressed by macrophages from the PAP patients, and the expression was reduced according to foaming of the cells; there were monocyte-like macrophages with strong expression, small foamy cells with moderate expression, large foamy cells with a faint expression of MCP-1, and ghost cells with no expression. However, the increase of macrophage number in the PAP BALF was relatively small. These data suggest that monocyte chemoattractant protein(-1) expression by alveolar macrophages represents an amplification mechanism for the recruitment of additional macrophages to the alveoli in pulmonary alveolar proteinosis. It is possible that an ingestion of an excess of alveolar materials in pulmonary alveolar proteinosis may impair the macrophage function and the survival, resulting in the lack of a prominent

  8. Short communication: Association of milk fatty acids with early lactation hyperketonemia and elevated concentration of nonesterified fatty acids.

    PubMed

    Mann, S; Nydam, D V; Lock, A L; Overton, T R; McArt, J A A

    2016-07-01

    The objective of our study was to extend the limited research available on the association between concentrations of milk fatty acids and elevated nonesterified fatty acids (NEFA) and β-hydroxybutyrate (BHB) concentrations in early lactation dairy cattle. Measurement of milk fatty acids for detection of cows in excessive negative energy balance has the potential to be incorporated in routine in-line monitoring systems. Blood samples were taken from 84 cows in second or greater lactation 3 times per week between 3 to 14 d in milk. Cows were characterized as hyperketonemic (HYK) if blood BHB concentration was ≥1.2mmol/L at least once and characterized as having elevated concentrations of NEFA (NEFAH) if serum NEFA concentration was ≥1mmol/L at least once. Composition of colostrum and milk fatty acids at wk 2 postpartum was used to investigate the potential diagnostic value of individual fatty acids and fatty acid ratios for the correct classification of cows with NEFA and BHB concentrations above these thresholds, respectively. Receiver operating characteristic (ROC) curves were used to identify thresholds of fatty acid concentration and fatty acid ratios when ROC area under the curve was ≥0.70. Correct classification rate (CCR, %) was calculated as {[(number of true positives + number of true negatives)/total number tested] × 100}. None of the colostrum fatty acids yielded a sufficiently high area under the curve in ROC analysis for the association with HYK and NEFAH. The following fatty acids and fatty acid ratios were identified for an association with NEFAH (threshold, CCR): C15:0 (≤0.65g/100g, 68.3%); cis-9 C16:1 (≥1.85g/100g, 70.7%); cis-9 C18:1 (≥26g/100g, 69.5%), cis-9 C18:1 to C15:0 ratio (≥45, 69.5%); cis-9 C16:1 to C15:0 (≥2.50, 73.2%). Several fatty acids were associated with HYK (threshold, CCR): C6:0 (≤1.68g/100g, 80.5%), C8:0 (≤0.80g/100g, 80.5%), C10:0 (≤1.6g/100g, 79.3%); C12:0 (≤1.42g/100g, 82.9%); C14:0 (≤6.10g/100g, 84

  9. Elevated Fasting Blood Glucose Is Predictive of Poor Outcome in Non-Diabetic Stroke Patients: A Sub-Group Analysis of SMART

    PubMed Central

    Zhou, Lixin; Peng, Bin; Zhu, Yicheng; Cui, Liying

    2016-01-01

    Background Although increasing evidence suggests that hyperglycemia following acute stroke adversely affects clinical outcome, whether the association between glycaemia and functional outcome varies between stroke patients with\\without pre-diagnosed diabetes remains controversial. We aimed to investigate the relationship between the fasting blood glucose (FBG) and the 6-month functional outcome in a subgroup of SMART cohort and further to assess whether this association varied based on the status of pre-diagnosed diabetes. Methods Data of 2862 patients with acute ischemic stroke (629 with pre-diagnosed diabetics) enrolled from SMART cohort were analyzed. Functional outcome at 6-month post-stroke was measured by modified Rankin Scale (mRS) and categorized as favorable (mRS:0–2) or poor (mRS:3–5). Binary logistic regression model, adjusting for age, gender, educational level, history of hypertension and stroke, baseline NIHSS and treatment group, was used in the whole cohort to evaluate the association between admission FBG and functional outcome. Stratified logistic regression analyses were further performed based on the presence/absence of pre-diabetes history. Results In the whole cohort, multivariable logistical regression showed that poor functional outcome was associated with elevated FBG (OR1.21 (95%CI 1.07–1.37), p = 0.002), older age (OR1.64 (95% CI1.38–1.94), p<0.001), higher NIHSS (OR2.90 (95%CI 2.52–3.33), p<0.001) and hypertension (OR1.42 (95%CI 1.13–1.98), p = 0.04). Stratified logistical regression analysis showed that the association between FBG and functional outcome remained significant only in patients without pre-diagnosed diabetes (OR1.26 (95%CI 1.03–1.55), p = 0.023), but not in those with premorbid diagnosis of diabetes (p = 0.885). Conclusion The present results demonstrate a significant association between elevated FBG after stroke and poor functional outcome in patients without pre-diagnosed diabetes, but not in diabetics

  10. Glucose fluxes and concentrations of dissolved combined neutral sugars (polysaccharides) in the Ross Sea and Polar Front Zone, Antarctica

    NASA Astrophysics Data System (ADS)

    Kirchman, David L.; Meon, Benedikt; Ducklow, Hugh W.; Carlson, Craig A.; Hansell, Dennis A.; Steward, Grieg F.

    We hypothesized that dissolved carbohydrates would be large components of the labile dissolved organic carbon (DOC) pool and would support much bacterial growth in Antarctic waters, especially the Ross Sea, since previous work had observed extensive phytoplankton blooms with potentially high production rates of carbohydrates in Antarctic seas. These hypotheses were tested on cruises in the Ross Sea and Antarctic Polar Front Zone as part of the US JGOFS program. Concentrations and fluxes of free glucose (the only free sugar detected) were very low, but dissolved polysaccharides appeared to be important components of the DOC pool. Concentrations of dissolved combined neutral sugars increased >3-fold during the phytoplankton bloom in the Ross Sea and were a large fraction (ca. 50%) of the semi-labile fraction of DOC. The relatively high concentrations of dissolved combined neutral sugars, which are thought to be quite labile, appear to explain why DOC accumulated during the phytoplankton bloom was degraded so quickly once the bloom ended. Some of the polysaccharides appeared to be more refractory, however, since dissolved combined neutral sugars were observed in deep waters (>550 m) and in early spring (October) in the Ross Sea, apparently having survived degradation for >8 months. The molecular composition of these refractory polysaccharides differed from that of polysaccharides sampled during the phytoplankton bloom. Fluxes of DOC were low in the Ross Sea compared to standing stocks and fluxes of particulate material, but the DOC that did accumulate during the phytoplankton bloom appeared to be sugar-rich and relatively labile.

  11. Derivation of a target concentration of Pb in soil based on elevation of adult blood pressure

    SciTech Connect

    Stern, A.H.

    1996-04-01

    The increase in systolic blood pressure in males appears to be the most sensitive adult endpoint appropriate for deriving a health risk-based target level of lead (Ph) in soil. Because the response of blood pressure to blood Ph concentration (PbB) has no apparent threshold, traditional approaches based on the application of a Reference Dose (RfD) are not applicable. An alternative approach is presented based on a model which predicts the population shift in systolic blood pressure from ingestion of Pb contaminated soil as a simultaneous function of exposure to Pb in soil, the baseline distribution of blood Pb concentration in the population and the baseline distribution of systolic pressure in the population. This model is analyzed using Monte Carlo analysis to predict the population distribution of systolic pressure resulting from Ph exposure. Based on this analysis, it is predicted that for adult males 18-65 years old, exposure to 1000 ppm Pb in soil will result in an increase of approximately 1 mm Hg systolic pressure, an increase in the incidence of systolic hypertension (i.e., systolic pressure >140 mm Hg) of approximately 1% and an increase in PbB of 1-3 {mu}g/dl. Based on the proposition that these adverse effects can be considered de minimis, 1000 ppm Ph in soil is proposed as a target soil concentration for adult exposure. Available data do not appear to be adequate to predict the newborn PbB level which would result from exposure to this soil level during pregnancy, 36 refs., 6 figs.

  12. Crevice corrosion - NaCl concentration map for grade-2 titanium at elevated temperature

    SciTech Connect

    Tsujikawa, Shigeo; Kojima, Yoichi

    1993-12-31

    The repassivation potential, ER, for metal/metal-crevice of Commercially Pure Titanium, C.P.Ti, was determined in NaCl solutions at temperatures up to 250C. The ER has its least noble value near 100C and becomes more noble as the temperature increases. As shown in previous research, the shrinkage of the repassivation region should continue with increasing temperatures. However, in conducting this same experiment at temperatures higher than 100C, an examination of the NaCl concentration - temperature - crevice corrosion map verifies that the repassivation region began to expand again when the temperature exceeded 140C. This expansion continued as the temperature continued to increase.

  13. Elevated acetate concentrations in the rhizosphere of Spartina alterniflora and potential influences on sulfate reduction

    NASA Technical Reports Server (NTRS)

    Hines, Mark E.; Tugel, Joyce B.; Giblin, A. E.; Banta, G. T.; Hobbie, J. E.

    1992-01-01

    Acetate is important in anaerobic metabolism of non-vegetated sediments but its role in salt marsh soils was not investigated thoroughly. Acetate concentrations, oxidation (C-14) and SO4(2-) reduction (S-35) were measured in S. alterniflora soils in NH and MA. Pore water from cores contained greater than 0.1 mM acetate and in some instances greater than 1.0 mM. Non-destructive samples contained less than 0.01 mM. Acetate was associated with roots and concentrations were highest during vegetative growth and varied with changes in plant physiology. Acetate turnover was very low whether whole core or slurry incubations were used. Radiotracers injected directly into soils yielded rates of SO4(2-) reduction and acetate oxidation not significantly different from core incubation techniques. Regardless of incubation method, acetate oxidation did not account for a significant percentage of SO4(2-) reduction. These results differ markedly from data for non-vegetated coastal sediments where acetate levels are low, oxidation rate constants are high and acetate oxidation rates greatly exceed rates of SO4(2-) reduction. The discrepancy between rates of acetate oxidation and SO4(2-) reduction in marsh soils may be due either to the utilization of substrates other than acetate by SO4(2-) reducers or artifacts associated with measurements of organic utilization by rhizosphere bacteria.

  14. Environmental Conditions Associated with Elevated Vibrio parahaemolyticus Concentrations in Great Bay Estuary, New Hampshire

    PubMed Central

    Urquhart, Erin A.; Jones, Stephen H.; Yu, Jong W.; Schuster, Brian M.; Marcinkiewicz, Ashley L.; Whistler, Cheryl A.; Cooper, Vaughn S.

    2016-01-01

    Reports from state health departments and the Centers for Disease Control and Prevention indicate that the annual number of reported human vibriosis cases in New England has increased in the past decade. Concurrently, there has been a shift in both the spatial distribution and seasonal detection of Vibrio spp. throughout the region based on limited monitoring data. To determine environmental factors that may underlie these emerging conditions, this study focuses on a long-term database of Vibrio parahaemolyticus concentrations in oyster samples generated from data collected from the Great Bay Estuary, New Hampshire over a period of seven consecutive years. Oyster samples from two distinct sites were analyzed for V. parahaemolyticus abundance, noting significant relationships with various biotic and abiotic factors measured during the same period of study. We developed a predictive modeling tool capable of estimating the likelihood of V. parahaemolyticus presence in coastal New Hampshire oysters. Results show that the inclusion of chlorophyll a concentration to an empirical model otherwise employing only temperature and salinity variables, offers improved predictive capability for modeling the likelihood of V. parahaemolyticus in the Great Bay Estuary. PMID:27144925

  15. Blood histamine concentrations are not elevated in humans with septic shock

    SciTech Connect

    Jacobs, R.; Kaliner, M.; Shelhamer, J.H.; Parrillo, J.E.

    1989-01-01

    Histamine has been suggested as an important mediator of the cardiovascular abnormalities during septic shock. To determine if blood histamine levels were increased during human sepsis and septic shock, plasma histamine was measured using a very sensitive radioenzyme assay employing histamine N-methyltransferase (HNMT) in the following patient groups: normal controls (n = 76), nonseptic critically ill (n = 12), nonseptic shock (n = 2), sepsis without shock (n = 28), and septic shock (n = 41). Using this enzyme binding assay, all these groups had similar, normal plasma histamine concentrations, except those patients with septic shock whose mean histamine measurements were significantly reduced (p less than .002). This decrease was found to be due to an artifact of the assay: plasma contained a circulating inhibitor that falsely lowered the measured histamine level. Fractionation of septic shock plasma using molecular exclusion membranes and gel filtration revealed a 5000 MW inhibitory factor. After removal of this inhibitor from plasma, septic shock plasma histamine levels were normal. Thus, septic shock patients may have a circulating inhibitor of the HNMT enzyme, but plasma histamine concentrations are normal. Histaminemia is unlikely to play an important role in the pathogenesis of septic shock in humans.

  16. Impact of elevated CO2 concentration on dynamics of leaf photosynthesis in Fagus sylvatica is modulated by sky conditions.

    PubMed

    Urban, Otmar; Klem, Karel; Holišová, Petra; Šigut, Ladislav; Šprtová, Mirka; Teslová-Navrátilová, Petra; Zitová, Martina; Špunda, Vladimír; Marek, Michal V; Grace, John

    2014-02-01

    It has been suggested that atmospheric CO2 concentration and frequency of cloud cover will increase in future. It remains unclear, however, how elevated CO2 influences photosynthesis under complex clear versus cloudy sky conditions. Accordingly, diurnal changes in photosynthetic responses among beech trees grown at ambient (AC) and doubled (EC) CO2 concentrations were studied under contrasting sky conditions. EC stimulated the daily sum of fixed CO2 and light use efficiency under clear sky. Meanwhile, both these parameters were reduced under cloudy sky as compared with AC treatment. Reduction in photosynthesis rate under cloudy sky was particularly associated with EC-stimulated, xanthophyll-dependent thermal dissipation of absorbed light energy. Under clear sky, a pronounced afternoon depression of CO2 assimilation rate was found in sun-adapted leaves under EC compared with AC conditions. This was caused in particular by stomata closure mediated by vapour pressure deficit. PMID:24316065

  17. Study of natural radionuclide concentrations in an area of elevated radiation background in the northern districts of Bangladesh.

    PubMed

    Hamid, B N; Chowdhury, M I; Alam, M N; Islam, M N

    2002-01-01

    The activity concentrations of naturally occurring radioactive materials in soil samples from an elevated radiation background area of three northern districts of Bangladesh were determined using gamma ray spectrometry. The outdoor and indoor external effective dose rates and the radiation hazard indices from these soil activities were evaluated. The dose rates were found to be about four times higher than the reported world average value. The concentration of natural radionuclides, derived radium equivalent activities and the representative level indices were also found to be higher. Recommendations on radiological and dosimetric measures have been suggested with an aim of minimising the harmful effects of ionising radiation to the population of the area concerned. PMID:11926374

  18. Wood properties of trembling aspen and paper birch after 5 years of exposure to elevated concentrations of CO(2) and O(3).

    PubMed

    Kostiainen, Katri; Kaakinen, Seija; Warsta, Elina; Kubiske, Mark E; Nelson, Neil D; Sober, Jaak; Karnosky, David F; Saranpää, Pekka; Vapaavuori, Elina

    2008-05-01

    We investigated the interactive effects of elevated concentrations of carbon dioxide ([CO(2)]) and ozone ([O(3)]) on radial growth, wood chemistry and structure of five 5-year-old trembling aspen (Populus tremuloides Michx.) clones and the wood chemistry of paper birch (Betula papyrifera Marsh.). Material for the study was collected from the Aspen FACE (free-air CO(2) enrichment) experiment in Rhinelander, WI, where the saplings had been exposed to four treatments: control, elevated [CO(2)] (560 ppm), elevated [O(3)] (1.5 x ambient) and their combination for five growing seasons. Wood properties of both species were altered in response to exposure to the treatments. In aspen, elevated [CO(2)] decreased uronic acids (constituents of, e.g., hemicellulose) and tended to increase stem diameter. In response to elevated [O(3)] exposure, acid-soluble lignin concentration decreased and vessel lumen diameter tended to decrease. Elevated [O(3)] increased the concentration of acetone-soluble extractives in paper birch, but tended to decrease the concentration of these compounds in aspen. In paper birch, elevated [CO(2)] decreased and elevated [O(3)] increased starch concentration. The responses of wood properties to 5 years of fumigation differed from those previously reported after 3 years of fumigation. PMID:18316312

  19. Elevated plasma haptoglobin concentrations following parturition are associated with elevated leukocyte responses and decreased subsequent reproductive efficiency in multiparous Holstein dairy cows.

    PubMed

    Nightingale, Cameron R; Sellers, Matthew D; Ballou, Michael A

    2015-03-15

    The objectives were to describe the relationship between the intensity of the acute phase response and the metabolic status and leukocyte responses of early postpartum, multiparous cows and determine if subsequent reproductive performance was impaired in cows with a greater acute phase response. Peripheral blood was collected from 240 Holstein cows, 2-8 days in milk and 2nd-8th parity from 8 dairies in Western TX and Eastern NM across 5 days (n=6 cows/dairy/day). Plasma concentrations of haptoglobin were measured and cows were classified as Low (1st quartile), Moderate (2nd and 3rd quartiles), or High (4th quartile) responders. Metabolic measurements included: plasma glucose, urea nitrogen, non-esterified fatty acids and β-hydroxybutyrate concentrations. Leukocyte response measurements included: total leukocyte counts and differentials, neutrophil surface expression of L-selectin, neutrophil oxidative burst capacity when co-cultured with an environmental Escherichia coli, as well as the secretion of tumor necrosis factor-α and interferon-γ when diluted whole blood were co-cultured with lipopolysaccharide and phytohemagglutinin-P, respectively. All data are reported as Low, Moderate, and High haptoglobin responders. Plasma haptoglobin concentrations ranged from below the limit of detection to 8.4 μg/mL, 8.5 to 458 μg/mL, and 459 to 1757 μg/mL. The High cows had more severe neutropenia (3.45, 3.31, and 2.23 ± 0.31 × 10(6)cells/mL; P=0.013) Additionally, the innate leukocyte responses of the High cows were stimulated as evident by increased secretion of tumor necrosis factor-α (568, 565, and 730 ± 73.4 pg/mL; P=0.003), surface expression of L-selectin on neutrophils (70.8, 71.9, and 119.8 ± 7.9 geometric mean fluorescence intensity; P=0.001), and greater neutrophil oxidative burst capacity (37.9, 40.4, and 47.9 ± 0.31 geometric mean fluorescence intensity; P=0.002). In contrast, the secretion of the T-lymphocyte derived cytokine, interferon-γ, was

  20. Acutely elevated vasopressin increases circulating concentrations of cortisol and aldosterone in fasting northern elephant seal (Mirounga angustirostris) pups

    NASA Technical Reports Server (NTRS)

    Ortiz, Rudy M.; Wade, Charles E.; Ortiz, C. Leo; Talamantes, Frank

    2003-01-01

    The physiological actions of vasopressin (VP) in marine mammals are not well defined. To help elucidate its hormonal and renal effects in this group of mammals, northern elephant seal (Mirounga angustirostris) pups (N=7; 99+/-4 kg) were first infused with 0.9% saline (control; 220 ml), followed 24 h later with VP (as a 20 ng kg(-1) bolus, then 2 ng kg(-1) min(-1) for approximately 35 min in 225+/-16 ml saline). During both control and VP periods, blood samples were collected prior to infusion, and 15, 30, 60, 120 min and 24 h after infusion to examine the hormonal responses of the pups to VP. Renal responses were quantified from 24 h urine samples obtained prior to infusion (control) and 24 h post-infusion. Compared to the control period, infusion of VP increased plasma concentrations of cortisol over a 120 min period and aldosterone over 30 min, while plasma renin activity (PRA) was decreased for a 120 min period. The plasma urea:creatinine ratio was elevated following infusion of VP. Urine output and osmotic clearance were increased by 69+/-18% (mean +/- S.E.M.) and 36+/-10%, respectively, but free water clearance and glomerular filtration rate were not significantly altered 24 h post-infusion of VP. Solute (osmolality, Na(+), K(+) and Cl(-)) excretion and fractional excretion of electrolytes were also increased when compared to control values. The increase in cortisol concentration suggests that VP may possess corticotropin releasing hormone-like activity in elephant seals. If osmotic diuresis and natriuresis are typical consequences of elevated [VP] in fasting pups, then not increasing VP normally during the fast may serve as a protective mechanism to avoid the potential loss of Na(+) induced by elevated [VP]. Therefore, under natural fasting conditions, pups may be highly sensitive to small changes in [VP], resulting in the maintenance of water and electrolyte balance.

  1. Effects of chronic elevated ozone concentration on the redox state and fruit yield of red pepper plant Capsicum baccatum.

    PubMed

    Bortolin, Rafael Calixto; Caregnato, Fernanda Freitas; Divan, Armando Molina; Reginatto, Flávio Henrique; Gelain, Daniel Pens; Moreira, José Cláudio Fonseca

    2014-02-01

    Ozone (O3) is one of the most harmful air pollutants to crops, contributing to high losses on crop yield. Tropospheric O3 background concentrations have increased since pre-industrial times reaching phytotoxic concentrations in many world regions. Capsicum peppers are the second most traded spice in the world, but few studies concerning the O3 effects in this genus are known. Thereby, the aim of this work was to evaluate the effects of chronic exposure to elevated O3 concentrations in red pepper plant Capsicum baccatum L. var. pendulum with especial considerations on the leaf redox state and fruit yield. Fifteen C. baccatum plants were exposed to O3 in open-top chambers during fruit ripening (62 days) at a mean concentration of 171.6 µg/m(3) from 10:00 am to 4:00 pm. We found that O3 treated plants significantly decreased the amount and the total weight of fruits, which were probably a consequence of the changes on leaf oxidative status induced by ozone exposure. Ozone exposed plants increased the reactive oxygen species (ROS) levels on the leaves, which may be associated with the observed decrease on the activity of enzymatic antioxidant defense system, as well with lower levels of polyphenol and reduced thiol groups. Enhanced ROS production and the direct O3 reaction lead to biomacromolecules damages as seen in the diminished chlorophyll content and in the elevated lipid peroxidation and protein carbonylation levels. Through a correlation analysis it was possible to observe that polyphenols content was more important to protect pepper plants against oxidative damages to lipids than to proteins. PMID:24238720

  2. Drug−disease interaction: Crohn's disease elevates verapamil plasma concentrations but reduces response to the drug proportional to disease activity

    PubMed Central

    Sanaee, Forough; Clements, John D; Waugh, Alistair W G; Fedorak, Richard N; Lewanczuk, Richard; Jamali, Fakhreddin

    2011-01-01

    AIM Inflammation is involved in the pathogenesis of cardiovascular diseases that includes reduced response to pharmacotherapy due to altered pharmacokinetics and pharmacodynamics. It is not known if these effects exist in general in all inflammatory conditions. It also remains unknown whether in a given population the effect is a function of disease severity. We investigated whether pharmacokinetics and pharmacodynamics of a typical calcium channel inhibitor are influenced by Crohn's disease (CD), a disease for which the disease severity can be readily ranked. METHODS We administered 80 mg verapamil orally to (i) healthy control subjects (n = 9), (ii) patients with clinically quiescent CD (n = 22) and (iii) patients with clinically active CD (n = 14). Serial analysis of verapamil enantiomers (total and plasma unbound), blood pressure and electrocardiograms were recorded over 8 h post dose. The severity of CD was measured using the Harvey-Bradshaw Index. RESULTS CD substantially and significantly increased plasma verapamil concentration and in a stereoselective fashion (S, 9-fold; R, 2-fold). The elevated verapamil concentration, however, failed to result in an increased verapamil pharmacodynamic effect so that the patients with elevated verapamil concentration demonstrated no significant increase in response measured as PR interval and blood pressure. Instead, the greater the disease severity, the lower was the drug potency to prolong PR interval (r = 0.86, P < 0.0006), CONCLUSIONS CD patients with severe disease may not respond to cardiovascular therapy with calcium channel blockers. Reducing the severity increases response despite reduced drug concentration. This observation may have therapeutic implication beyond the disease and the drug studies herein. PMID:21592185

  3. Effect of High Glucose Concentration on Collagen Synthesis and Cholesterol Level in the Phenotypic Modulation of Aortic Cultured Smooth Muscle Cells of Sand Rat (Psammomys obesus)

    PubMed Central

    Bouguerra, S. Aouichat; Benazzoug, Y.; Bekkhoucha, F.; Bourdillon, M. C.

    2004-01-01

    To simulate diabetic conditions, the effects of high glucose concentration on collagen synthesis and cholesterol level in cultured aortic smooth muscle cells of Psammomys were investigated. For collagen biosynthesis, smooth muscle cells (SMCs) were incubated in synthetic proliferative phase and in postconfluent phase with 3H-proline. Cellular cholesterol was determined by enzymatic method. Under high glucose concentration, the results showed morphological modifications characterized by morphometric cellular, nuclear, and nucleolar changes. In biochemical studies, the authors observed an increase of free and esterified cellular cholesterol as well as of total proteins, collagen biosynthesis, and α1 (I+III) and α2 (I) chains of collagen contained in the SMCs and in the extracellular matrix. These results showed the sensitivity of Psammomys aortic SMCs to high glucose concentration and would constitute an interesting cellular model to study atherosclerosis pathogeny in experimental diabetes. PMID:15512791

  4. An examination of utility emissions contributions to elevated ozone concentrations in the Chicago area

    SciTech Connect

    Fernau, M.E.; Guziel, K.A.; South, D.W.

    1993-05-01

    In order to reduce the pollutant load to the atmosphere and subsequent damaging effects, Titles I and IV of the Clean Air Act Amendments of 1990 (CAAAs) require reductions in emissions of sulfur dioxide (SO{sub 2}), nitrogen oxides (NO{sub x}), and volatile organic compounds (VOCs). Title IV is aimed at reducing acidic deposition and requires utilities to reduce SO{sub 2} and NO{sub x} emissions to specified levels. As a consequence of this, many utilities will have to install SO{sub 2} and NO{sub x} control technologies. Title I is concerned with bringing regions into compliance with the National Ambient Air Quality Standards (NAAQS) for the criteria pollutants, among which is ozone (O{sub 3}). The NAAQS for O{sub 3} is 120 ppb (parts per billion by volume) hourly average concentration, not to be exceeded four times in three years. O{sub 3} is a secondary pollutant formed in the atmosphere when NO{sub x} and VOCs react together in the presence of sunlight. Utilities are a significant source of NO{sub x} and an unimportant source of VOCs. In the past, O{sub 3} control strategy has focused on reducing VOC emissions because of the possibility that reducing NO{sub x} actually might make O{sub 3} concentrations higher. However, this approach has not worked, perhaps because of underestimation of natural and manmade VOC emissions and transport of O{sub 3} from other regions. Computer modeling has shown that for many highly polluted areas massive NO{sub x} reductions may be necessary in addition to or in place of VOC controls. Utilities are a potential source of these NO{sub x} reductions.

  5. An examination of utility emissions contributions to elevated ozone concentrations in the Chicago area

    SciTech Connect

    Fernau, M.E.; Guziel, K.A.; South, D.W.

    1993-01-01

    In order to reduce the pollutant load to the atmosphere and subsequent damaging effects, Titles I and IV of the Clean Air Act Amendments of 1990 (CAAAs) require reductions in emissions of sulfur dioxide (SO[sub 2]), nitrogen oxides (NO[sub x]), and volatile organic compounds (VOCs). Title IV is aimed at reducing acidic deposition and requires utilities to reduce SO[sub 2] and NO[sub x] emissions to specified levels. As a consequence of this, many utilities will have to install SO[sub 2] and NO[sub x] control technologies. Title I is concerned with bringing regions into compliance with the National Ambient Air Quality Standards (NAAQS) for the criteria pollutants, among which is ozone (O[sub 3]). The NAAQS for O[sub 3] is 120 ppb (parts per billion by volume) hourly average concentration, not to be exceeded four times in three years. O[sub 3] is a secondary pollutant formed in the atmosphere when NO[sub x] and VOCs react together in the presence of sunlight. Utilities are a significant source of NO[sub x] and an unimportant source of VOCs. In the past, O[sub 3] control strategy has focused on reducing VOC emissions because of the possibility that reducing NO[sub x] actually might make O[sub 3] concentrations higher. However, this approach has not worked, perhaps because of underestimation of natural and manmade VOC emissions and transport of O[sub 3] from other regions. Computer modeling has shown that for many highly polluted areas massive NO[sub x] reductions may be necessary in addition to or in place of VOC controls. Utilities are a potential source of these NO[sub x] reductions.

  6. Improvement of cloned [alpha]-amylase gene expression in fed-batch culture of recombinant Saccharomyces cerevisiae by regulating both glucose and ethanol concentrations using a fuzzy controller

    SciTech Connect

    Shiba, Sumihisa; Nishida, Yoshio; Park, Y.S.; Iijima, Shinji; Kobayashi, Takeshi . Dept. of Biotechnology)

    1994-11-05

    The effect of ethanol concentration on cloned gene expression in recombinant Saccharomyces cerevisiae strain 20B-12 containing one of two plasmids, pNA3 and pNA7, was investigated in batch cultures. Plasmids pNA3 and pNA7 contain the [alpha]-amylase gene under the control of the SUC2 or PGK promoter, respectively. When the ethanol concentration was controlled at 2 to 5 g/L, the gene expressions were two times higher than those at 20 g/L ethanol. To increase the gene expression by maintaining both the ethanol and glucose concentrations at low levels, a fuzzy controller was developed. The concentrations of glucose and ethanol were controlled simultaneously at 0.15 and 2 g/L, respectively, in the production phase using the fuzzy controller in fed-batch culture. The synthesis of [alpha]-amylase was induced by the low glucose concentration and maintained at a high level of activity by regulating the ethanol concentration at 2 g/L. The secretory [alpha]-amylase activities of cells harboring plasmids pNA3 and pNA7 in fed-batch culture were 175 and 392 U/mL, and their maximal specific activities 7.7 and 12.4 U/mg dry cells, respectively. These values are two to three times higher in activity and three to four times higher in specific activity than those obtained when glucose only was controlled.

  7. Plasma secretin concentration in anaesthetized pigs after intraduodenal glucose, fat, aminoacids, or meals with various pH.

    PubMed

    Fahrenkrug, J; Schaffalitzky de Muckadell, O B; Holst, J J

    1977-01-01

    The concentration of immunoreactive secretin in portal blood and the secretion from the exocrine pancreas were measured during intraduodenal infusion of isotonic or hypertonic saline, isotonic or hypertonic glucose, aminoacids, fat emulsion, or 0.1 mol X 1(-1) hydrochloric acid in 7 anaesthetized pigs. None of these substances, except hydrochloric acid, had any effect on plasma secretin concentration and pancreatic flow rate and bicarbonate output. Plasma secretin concentration rose significantly from 5.6 +/- 2.7 pmol X 1(-1) (mean +/- S.E.M.) to a peak value of 201.2 +/- 80.5 pmol X 1(-1) 15 min after infusion of hydrochloric acid. Pancreatic flow rate and bicarbonate output increased from 0.51 +/- 0.19 ml X h-1 (mean +/- S.E.M.) to 9.85 +/- 2.33 ml X h-1 and from 52 +/- 11 micronmol X h-1 to 1.004 +/- 290 micronmol X h-1, respectively. During intraduodenal introduction of meals with pH adjusted from 1.0 to 7.0 in 4 pigs amylase was secreted at all pH levels. However, only when pH of the meal was 1.0, resulting in an intraduodenal pH from 1.0 to 1.7 during the stimulation, was a significant increase in plasma secretin concentration and pancreatic flow rate observed from 5.5 +/- 2.8 pmol X 1(-1) (mean +/- S.E.M.) to 115.0 +/- 51.2 pmol X 1(-1) and from 0.20 +/- 0.08 ml X h-1 to 6.25 +/- 2.57 ml X h-1, respectively. PMID:17153

  8. Elevating glucose and insulin secretion by carbohydrate formulation diets in late lactation to improve post-weaning fertility in primiparous sows.

    PubMed

    Chen, T Y; Lines, D; Dickson, C; Go, C; Kirkwood, R N; Langendijk, P

    2016-10-01

    Primiparous (P1) sows commonly lose excessive body reserves to meet energy requirements for maintenance and milk production during lactation, and consequently, post-weaning reproductive performance may be compromised. The present studies determined whether ad libitum feeding a glucogenic carbohydrate diet (CHO) during late lactation could stimulate insulin and glucose secretion (experiment 1) and improve subsequent litter size (experiment 2). For experiment 1, 15 P1 sows, and for experiment 2, 99 P1 sows (198.5 ± 2.7 kg) were allocated randomly according to suckled litter size (≥10 piglets), either to a CHO diet (14.3 MJ DE/kg, 19.8% crude protein) or a standard lactation diet (control; 14.2 DE MJ/kg, 19.5% crude protein) at 8 days before weaning. The CHO diet aimed to provide glucogenic content (extruded wheat, dextrose and sugar) as energy sources instead of fat sources without changing total dietary energy. Pre-prandial plasma glucose and insulin concentrations were not influenced by treatments. However, post-prandial plasma glucose and insulin concentrations and their peaks were both higher (p < .05) compared to the control treatment. Body weight loss during lactation was relatively low at 3%-4% for both treatments and did not differ between control and CHO treatments (-7.6 ± 1.6 vs -5.4 ± 1.2 kg; p > .05). Second litter size was not influenced by diet (p > .05), but the weaning-to-mating interval was shorter in CHO sows (p < .05). This study demonstrates that providing an enriched CHO diet in late lactation did influence post-weaning follicle growth but did not improve subsequent litter size. This may be due to the primiparous sows in this study not experiencing severe negative energy balance and there was no second litter syndrome in this farm which limited the ability of diet to improve sow fertility. PMID:27548995

  9. Marker-assisted selection for elevated concentrations of the a' subunit of B-conglycinin and its influence on agronomic and seed traits of soybean

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soybean [Glycine max (L.) Merr.] cultivars with elevated concentrations of the a' subunit of ß-conglycinin (BC) may provide health benefits to soy protein consumers. Two Monsanto single nucleotide polymorphism markers were used to classify F2 plants in four segregating populations as having elevate...

  10. Elevated water temperature and carbon dioxide concentration increase the growth of a keystone echinoderm

    PubMed Central

    Gooding, Rebecca A.; Harley, Christopher D. G.; Tang, Emily

    2009-01-01

    Anthropogenic climate change poses a serious threat to biodiversity. In marine environments, multiple climate variables, including temperature and CO2 concentration ([CO2]), are changing simultaneously. Although temperature has well-documented ecological effects, and many heavily calcified marine organisms experience reduced growth with increased [CO2], little is known about the combined effects of temperature and [CO2], particularly on species that are less dependent on calcified shells or skeletons. We manipulated water temperature and [CO2] to determine the effects on the sea star Pisaster ochraceus, a keystone predator. We found that sea star growth and feeding rates increased with water temperature from 5 °C to 21 °C. A doubling of current [CO2] also increased growth rates both with and without a concurrent temperature increase from 12 °C to 15 °C. Increased [CO2] also had a positive but nonsignificant effect on sea star feeding rates, suggesting [CO2] may be acting directly at the physiological level to increase growth rates. As in past studies of other marine invertebrates, increased [CO2] reduced the relative calcified mass in sea stars, although this effect was observed only at the lower experimental temperature. The positive relationship between growth and [CO2] found here contrasts with previous studies, most of which have shown negative effects of [CO2] on marine species, particularly those that are more heavily calcified than P. ochraceus. Our findings demonstrate that increased [CO2] will not have direct negative effects on all marine invertebrates, suggesting that predictions of biotic responses to climate change should consider how different types of organisms will respond to changing climatic variables. PMID:19470464

  11. Low plasma selenium concentration is associated with elevated risk to neoplastic polyps of the colon

    SciTech Connect

    Clark, L.C.; Hixson, L.G.; Sampliner, R.E. ); Combs, G.F. Jr. )

    1991-03-11

    A cross-sectional study was conducted to examine the relationship of selenium (Se) status and polyps incidence in a sequential series of 100 patients undergoing outpatient colonoscopies at the Tucson VA Hospital. Se was measured in plasma samples by electrothermal atomic absorption spectrophotometry with Zeeman background correction using a reduced palladium matrix modified. The activities of the Se-dependent enzyme glutathione peroxidase (SeGSHpx) were measured using H{sub 2}O{sub 2} as substrate in all plasma samples and in colonic mucosal biopsies obtained from some patients. The mean plasma Se concentration of patients without polyps was 134 ng/ml. Mean plasma Se levels of patients with only diminutive or large polyps were 127 ng/ml and 125 ng/ml; while patients with polyps of both sizes had a mean plasma Se level of 121 ng/ml. Patients with no reported history of cancer, neoplastic polyps or prior colonoscopy, showed an inverse association of plasma Se level and risk of benign colonic neoplasms. The age-adjusted odds ratio for neoplastic polyps was 3.8 for patients with plasma Se levels below vs. above the median value. This association was stronger for patients under 68 yrs of age than for older patients. Activities of SeGSHpx in plasma or colonic mucosa were not related to plasma Se level; however, smokers showed greater SeGSHpx activities than non-smokers. This study is the first to detect an association of Se status and risk to neoplastic polyps of the colon.

  12. Elevated concentrations of U and co-occurring metals in abandoned mine wastes in a northeastern Arizona Native American community

    SciTech Connect

    Blake, Johanna M.; Avasarala, Sumant; Artyushkova, Kateryna; Ali, Abdul -Mehdi S.; Brearley, Adrian J.; Shuey, Christopher; Robinson, Wm. Paul; Nez, Christopher; Bill, Sadie; Lewis, Johnnye; Hirani, Chris; Pacheco, Juan S. Lezama; Cerrato, José M.

    2015-07-09

    The chemical interactions of U and co-occurring metals in abandoned mine wastes in a Native American community in northeastern Arizona were investigated using spectroscopy, microscopy and aqueous chemistry. The concentrations of U (67–169 μg L–1) in spring water samples exceed the EPA maximum contaminant limit of 30 μg L–1. Elevated U (6,614 mg kg–1), V (15,814 mg kg–1), and As (40 mg kg–1) concentrations were detected in mine waste solids. Spectroscopy (XPS and XANES) solid analyses identified U (VI), As (-I and III) and Fe (II, III). Linear correlations for the release of U vs V and As vs Fe were observed for batch experiments when reacting mine waste solids with 10 mM ascorbic acid (~pH 3.8) after 264 h. The release of U, V, As, and Fe was at least 4-fold lower after reaction with 10 mM bicarbonate (~pH 8.3). These results suggest that U–V mineral phases similar to carnotite [K2(UO2)2V2O8] and As–Fe-bearing phases control the availability of U and As in these abandoned mine wastes. Elevated concentrations of metals are of concern due to human exposure pathways and exposure of livestock currently ingesting water in the area. This study contributes to understanding the occurrence and mobility of metals in communities located close to abandoned mine waste sites.

  13. Elevated concentrations of U and co-occurring metals in abandoned mine wastes in a northeastern Arizona Native American community

    DOE PAGESBeta

    Blake, Johanna M.; Avasarala, Sumant; Artyushkova, Kateryna; Ali, Abdul -Mehdi S.; Brearley, Adrian J.; Shuey, Christopher; Robinson, Wm. Paul; Nez, Christopher; Bill, Sadie; Lewis, Johnnye; et al

    2015-07-09

    The chemical interactions of U and co-occurring metals in abandoned mine wastes in a Native American community in northeastern Arizona were investigated using spectroscopy, microscopy and aqueous chemistry. The concentrations of U (67–169 μg L–1) in spring water samples exceed the EPA maximum contaminant limit of 30 μg L–1. Elevated U (6,614 mg kg–1), V (15,814 mg kg–1), and As (40 mg kg–1) concentrations were detected in mine waste solids. Spectroscopy (XPS and XANES) solid analyses identified U (VI), As (-I and III) and Fe (II, III). Linear correlations for the release of U vs V and As vs Femore » were observed for batch experiments when reacting mine waste solids with 10 mM ascorbic acid (~pH 3.8) after 264 h. The release of U, V, As, and Fe was at least 4-fold lower after reaction with 10 mM bicarbonate (~pH 8.3). These results suggest that U–V mineral phases similar to carnotite [K2(UO2)2V2O8] and As–Fe-bearing phases control the availability of U and As in these abandoned mine wastes. Elevated concentrations of metals are of concern due to human exposure pathways and exposure of livestock currently ingesting water in the area. This study contributes to understanding the occurrence and mobility of metals in communities located close to abandoned mine waste sites.« less

  14. Elevated Concentrations of U and Co-occurring Metals in Abandoned Mine Wastes in a Northeastern Arizona Native American Community.

    PubMed

    Blake, Johanna M; Avasarala, Sumant; Artyushkova, Kateryna; Ali, Abdul-Mehdi S; Brearley, Adrian J; Shuey, Christopher; Robinson, Wm Paul; Nez, Christopher; Bill, Sadie; Lewis, Johnnye; Hirani, Chris; Pacheco, Juan S Lezama; Cerrato, José M

    2015-07-21

    The chemical interactions of U and co-occurring metals in abandoned mine wastes in a Native American community in northeastern Arizona were investigated using spectroscopy, microscopy and aqueous chemistry. The concentrations of U (67-169 μg L(-1)) in spring water samples exceed the EPA maximum contaminant limit of 30 μg L(-1). Elevated U (6,614 mg kg(-1)), V (15,814 mg kg(-1)), and As (40 mg kg(-1)) concentrations were detected in mine waste solids. Spectroscopy (XPS and XANES) solid analyses identified U (VI), As (-I and III) and Fe (II, III). Linear correlations for the release of U vs V and As vs Fe were observed for batch experiments when reacting mine waste solids with 10 mM ascorbic acid (∼pH 3.8) after 264 h. The release of U, V, As, and Fe was at least 4-fold lower after reaction with 10 mM bicarbonate (∼pH 8.3). These results suggest that U-V mineral phases similar to carnotite [K2(UO2)2V2O8] and As-Fe-bearing phases control the availability of U and As in these abandoned mine wastes. Elevated concentrations of metals are of concern due to human exposure pathways and exposure of livestock currently ingesting water in the area. This study contributes to understanding the occurrence and mobility of metals in communities located close to abandoned mine waste sites. PMID:26158204

  15. Elevated intracellular calcium concentration increases secretory processing of the amyloid precursor protein by a tyrosine phosphorylation-dependent mechanism.

    PubMed Central

    Petryniak, M A; Wurtman, R J; Slack, B E

    1996-01-01

    Secretory cleavage of the amyloid precursor protein (APP), a process that releases soluble APP derivatives (APPs) into the extracellular space, is stimulated by the activation of muscarinic receptors coupled to phosphoinositide hydrolysis. The signalling pathways involved in the release process exhibit both protein kinase C- and protein tyrosine phosphorylation-dependent components [Slack, Breu, Petryniak, Srivastava and Wurtman (1995) J. Biol. Chem. 270, 8337-8344]. The possibility that elevations in intracellular Ca2+ concentration initiate the tyrosine phosphorylation-dependent release of APPs was examined in human embryonic kidney cells expressing muscarinic m3 receptors. Inhibition of protein kinase C with the bisindolylmaleimide GF 109203X decreased the carbachol-evoked release of APPs by approx. 30%, as shown previously. The residual response was further decreased, in an additive manner, by the Ca2+ chelator EGTA, or by the tyrosine kinase inhibitor tyrphostin A25. The Ca2+ ionophore, ionomycin, like carbachol, stimulated both the release of APPs and the tyrosine phosphorylation of several proteins, one of which was identified as paxillin, a component of focal adhesions. The effects of ionomycin on APPs release and on protein tyrosine phosphorylation were concentration-dependent, and occurred over similar concentration ranges; both effects were inhibited only partly by GF 109203X, but were abolished by EGTA or by tyrosine kinase inhibitors. The results demonstrate for the first time that ionophore-induced elevations in intracellular Ca2+ levels elicit APPs release via increased tyrosine phosphorylation. Part of the increase in APPs release evoked by muscarinic receptor activation might be attributable to a similar mechanism. PMID:9003386

  16. Metformin inhibition of mTORC1 activation, DNA synthesis and proliferation in pancreatic cancer cells: Dependence on glucose concentration and role of AMPK

    SciTech Connect

    Sinnett-Smith, James; Kisfalvi, Krisztina; Kui, Robert; Rozengurt, Enrique

    2013-01-04

    Highlights: Black-Right-Pointing-Pointer Metformin inhibits cancer cell growth but the mechanism(s) are not understood. Black-Right-Pointing-Pointer We show that the potency of metformin is sharply dependent on glucose in the medium. Black-Right-Pointing-Pointer AMPK activation was enhanced in cancer cells incubated in physiological glucose. Black-Right-Pointing-Pointer Reciprocally, metformin potently inhibited mTORC1, DNA synthesis and proliferation. Black-Right-Pointing-Pointer Metformin, at low concentrations, inhibited DNA synthesis through AMPK. -- Abstract: Metformin, a widely used anti-diabetic drug, is emerging as a potential anticancer agent but the mechanisms involved remain incompletely understood. Here, we demonstrate that the potency of metformin induced AMPK activation, as shown by the phosphorylation of its substrates acetyl-CoA carboxylase (ACC) at Ser{sup 79} and Raptor at Ser{sup 792}, was dramatically enhanced in human pancreatic ductal adenocarcinoma (PDAC) cells PANC-1 and MiaPaCa-2 cultured in medium containing physiological concentrations of glucose (5 mM), as compared with parallel cultures in medium with glucose at 25 mM. In physiological glucose, metformin inhibited mTORC1 activation, DNA synthesis and proliferation of PDAC cells stimulated by crosstalk between G protein-coupled receptors and insulin/IGF signaling systems, at concentrations (0.05-0.1 mM) that were 10-100-fold lower than those used in most previous reports. Using siRNA-mediated knockdown of the {alpha}{sub 1} and {alpha}{sub 2} catalytic subunits of AMPK, we demonstrated that metformin, at low concentrations, inhibited DNA synthesis through an AMPK-dependent mechanism. Our results emphasize the importance of using medium containing physiological concentrations of glucose to elucidate the anticancer mechanism of action of metformin in pancreatic cancer cells and other cancer cell types.

  17. High concentrations of glucose suppress etoposide-induced cell death of B-cell lymphoma through BCL-6.

    PubMed

    Shao, Yan; Ling, Chang Chun; Liu, Xu Qing

    2014-07-18

    Glucose is potentially a factor in the resistance to chemotherapy of B-cell lymphomas. In this study we investigated the expression of the glucose induced transcription factor Bcl-6 and the underlying mechanism by which it suppresses B-cell lymphoma cell death. Glucose was found to prevent etoposide-induced tumor cell death. BCL-6 expression was induced by glucose but down-regulated by etoposide. BCL-6 expression was regulated by the interaction of VDUP1 and p53. The molecular mechanism by which glucose prevented etoposide-induced tumor cell death was shown to involve the BCL-6 mediated caspase pathway. Our data suggest that glucose-induced BCL-6 overexpression could abrogate the etoposide chemotherapy effect on tumor cell death. PMID:24878528

  18. Elevated plasma and urinary concentrations of green tea catechins associated with improved plasma lipid profile in healthy Japanese women.

    PubMed

    Takechi, Ryusuke; Alfonso, Helman; Hiramatsu, Naoko; Ishisaka, Akari; Tanaka, Akira; Tan, La'Belle; Lee, Andy H

    2016-03-01

    This study investigated green tea catechins in plasma and urine and chronic disease biomarkers. We hypothesized that plasma and urinary concentration of green tea catechins are associated with cardiovascular disease and diabetes biomarkers. First void urine and fasting plasma samples were collected from 57 generally healthy females aged 38 to 73 years (mean, 52 ± 8 years) recruited in Himeji, Japan. The concentrations of plasma and urinary green tea catechins were determined by liquid chromatography coupled with mass tandem spectrometer. Low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, triglyceride, glucose, insulin, glycated hemoglobin, and C-reactive protein in plasma/serum samples were analyzed by a commercial diagnostic laboratory. Statistical associations were assessed using Spearman correlation coefficients. The results showed weak associations between plasma total catechin and triglyceride (r = -0.30) and LDL cholesterol (r = -0.28), whereas plasma (-)-epigallocatechin-3-gallate, (-)-epigallocatechin, (-)-epicatechin-3-gallate, and (-)-epicatechin exhibited weak to moderate associations with triglyceride or LDL cholesterol, but little associations with HDL cholesterol, body fat, and body mass index were evident. Urinary total catechin was weakly associated with triglyceride (r = -0.19) and LDL cholesterol (r = -0.15), whereas urinary (-)-epigallocatechin-3-gallate (r = -0.33), (-)-epigallocatechin (r = -0.23), and (-)-epicatechin-3-gallate (r = -0.33) had weak to moderate correlations with triglyceride and similarly with body fat and body mass index. Both plasma (r = -0.24) and urinary (r = -0.24) total catechin, as well as individual catechins, were weakly associated with glycated hemoglobin. Plasma total and individual catechins were weakly to moderately associated with C-reactive protein, but not the case for urinary catechins. In conclusion, we found weak to moderate associations between plasma and urinary green tea

  19. Effect of Growth Rate and Glucose Concentration on the Biochemical Properties of Streptococcus mutans Ingbritt in Continuous Culture

    PubMed Central

    Hamilton, I. R.; Phipps, P. J.; Ellwood, D. C.

    1979-01-01

    A comparison was made of the properties of Streptococcus mutans Ingbritt grown in continuous culture under conditions of excess glucose (nitrogen limitation) and limiting glucose at mean generation times of 1.7 to 14 h. Only low levels of glucoamylase-specific glycogen were formed in cells from either culture, and the total carbohydrate content of the cells under excess glucose was only at most 1.6-fold higher than in the glucose-limited culture. A negligible amount of cell-free polysaccharide was formed in either culture, although a significant level of glucosyltransferase activity was observed in both, with the highest activity at D = 0.2 and 0.4 h-1 with a glucose limitation. Other differences were observed. (i) Lactate was the main end product of the glucose-excess culture, whereas acetate, formate, and ethanol were the main products of the glucose-limited culture except at a mean generation time of 1.5, when lactate represented 30% of the products. (ii) The yield (in grams per mole of glucose) of the latter culture was 2.6- to 4.0- fold higher than the yield of the glucose-excess culture. (iii) Washed cells from the glucose-limited culture were much more acidogenic (1.7- to 6.2-fold) than the glucose-excess cells when incubated with glucose, sucrose, and fructose. Endogenous glycolytic activity by the latter cells was significant, being 31 to 92% of the exogenous glucose rate at the four dilution rates. (iv) Cells from the glucose-excess culture were more insensitive to fluoride than cells from the glucose-limited culture. The NaF 50% inhibition dose values for the effect of fluoride on the metabolism of glucose, sucrose, and fructose were calculated for the four dilution rates at four pH values. This analysis indicated that rapidly metabolizing cells were more sensitive to fluoride than cells that metabolized the sugars more slowly. PMID:43291

  20. Probability of detecting atrazine/desethyl-atrazine and elevated concentrations of nitrate in ground water in Colorado

    USGS Publications Warehouse

    Rupert, Michael G.

    2003-01-01

    Draft Federal regulations may require that each State develop a State Pesticide Management Plan for the herbicides atrazine, alachlor, metolachlor, and simazine. Maps were developed that the State of Colorado could use to predict the probability of detecting atrazine and desethyl-atrazine (a breakdown product of atrazine) in ground water in Colorado. These maps can be incorporated into the State Pesticide Management Plan and can help provide a sound hydrogeologic basis for atrazine management in Colorado. Maps showing the probability of detecting elevated nitrite plus nitrate as nitrogen (nitrate) concentrations in ground water in Colorado also were developed because nitrate is a contaminant of concern in many areas of Colorado. Maps showing the probability of detecting atrazine and(or) desethyl-atrazine (atrazine/DEA) at or greater than concentrations of 0.1 microgram per liter and nitrate concentrations in ground water greater than 5 milligrams per liter were developed as follows: (1) Ground-water quality data were overlaid with anthropogenic and hydrogeologic data using a geographic information system to produce a data set in which each well had corresponding data on atrazine use, fertilizer use, geology, hydrogeomorphic regions, land cover, precipitation, soils, and well construction. These data then were downloaded to a statistical software package for analysis by logistic regression. (2) Relations were observed between ground-water quality and the percentage of land-cover categories within circular regions (buffers) around wells. Several buffer sizes were evaluated; the buffer size that provided the strongest relation was selected for use in the logistic regression models. (3) Relations between concentrations of atrazine/DEA and nitrate in ground water and atrazine use, fertilizer use, geology, hydrogeomorphic regions, land cover, precipitation, soils, and well-construction data were evaluated, and several preliminary multivariate models with various

  1. Cytotoxicity of β-D-glucose/sucrose-coated silver nanoparticles depends on cell type, nanoparticles concentration and time of incubation

    NASA Astrophysics Data System (ADS)

    Vergallo, Cristian; Panzarini, Elisa; Carata, Elisabetta; Ahmadi, Meysam; Mariano, Stefania; Tenuzzo, Bernardetta Anna; Dini, Luciana

    2016-06-01

    The use of silver NanoParticles (AgNPs) in several consumer commercialized products, like food contact materials, medical devices and cosmetics has increased significantly, owing to their antibacterial and antifungal properties. Even though the NPs are widely diffused, due to the great variety in size, coating or shape, controversial data on their possible detrimental health effects still exist. Herein, by performing an easy and fast green method synthesis, we used β-D-glucose/sucrose to stabilize AgNPs and avoid the release of cytotoxic soluble silver ions Ag+ in the culture medium. The cytotoxic effects of these β-D-Glucose/Sucrose-Coated AgNPs (AgNPs-GS) was assessed on two cell culture models, which are human liver HepG2 and human Peripheral Blood Lymphocytes (PBLs) cells. AgNPs-GS, as determined by Transmission Electron Microscopy (TEM) analyses, had an average diameter of 30±5 nm, a spherical shape and were well-dispersed in the freshly-prepared solution. In addition, they were found spectrophotometrically stable throughout the experiment. Cytotoxicity, determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction assay, was evaluated by using two AgNPs-GS amounts, indicated as highest (10×103 of NPs/cell) and lowest (2×103 NPs/cell) concentration for 6, 12 and 24 h. The highest concentration of AgNPs-GS was significantly cytotoxic for both HepG2 and PBLs cells at all times, when compared with the negative control; conversely, the lowest amount of AgNPs-GS was toxic only for HepG2 cells. A significant increase of Reactive Oxygen Species (ROS) levels, determined by Nitro Blue Tetrazolium (NBT) reduction assay, was observed only in PBLs after treatment with NPs, by reaching maximum levels after the incubation with the lowest amount of NPs for 24 h. Significant morphological changes, depending on NPs/cell amount, characteristic of cell toxicity, like shape, cytoplasm, and nucleus alterations, were observed in lymphocytes and Hep

  2. Na+ /Ca2+ exchanger contributes to asterosap-induced elevation of intracellular Ca2+ concentration in starfish spermatozoa.

    PubMed

    Islam, M Sadiqul; Kawase, Osamu; Hase, Sumitaka; Minakata, Hiroyuki; Hoshi, Motonori; Matsumoto, Midori

    2006-05-01

    Asterosap, a group of equally active isoforms of sperm-activating peptides from the egg jelly of the starfish Asterias amurensis, functions as a chemotactic factor for sperm. It transiently increases the intracellular cGMP level of sperm, which in turn induces a transient elevation of intracellular Ca(2+) concentration ([Ca(2+)](i)). Using a fluorescent Ca(2+)-sensitive dye, Fluo-4 AM, we measured the changes in sperm [Ca(2+)](i) in response to asterosap. KB-R7943 (KB), a selective inhibitor of Na(+)/Ca(2+) exchanger (NCX), significantly inhibited the asterosap-induced transient elevation of [Ca(2+)](i), suggesting that asterosap influences [Ca(2+)](i) through activation of a K+-dependent NCX (NCKX). An NCKX activity of starfish sperm also shows K(+) dependency like other NCKXs. Therefore, we cloned an NCKX from the starfish testes and predicted that it codes for a 616 amino acid protein that is a member of the NCKX family. Pharmacological evidence suggests that this exchanger participates in the asterosap-induced Ca(2+) entry into sperm. PMID:16719949

  3. Inlay osteotome sinus floor elevation with concentrated growth factor application and simultaneous short implant placement in severely atrophic maxilla.

    PubMed

    Chen, Yonghui; Cai, Zhiyu; Zheng, Dingguo; Lin, Pei; Cai, Yahua; Hong, Shuxin; Lai, Yiwei; Wu, Dong

    2016-01-01

    Sinus floor elevation with simultaneous implant placement in severely atrophic maxilla is challenging. The aim of this retrospective study was to evaluate the short-term performance of modified osteotome sinus floor elevation (OSFE) with concentrated growth factor (CGF) application and concurrent placement of a short implant in cases with residual bone height (RBH) of 2-4 mm. Twenty-five short implants were installed in 16 patients with mean RBH of 3.23 mm using modified OSFE with CGFs from January 2012 to April 2014. Postoperatively, the implants were clinically evaluated, and vertical bone gain (VBG) was measured using cone beam computed tomography. The mean duration of follow-up was 19.88 months (12-32 months). All the implants were stable with an overall survival rate of 100%. The mean VBG immediately after surgery was 9.21 mm. Six months later, significant reduction of alveolar bone height (2.90 ± 0.22 mm) was found (P < 0.05). During the second 6-month period, further alveolar bone resorption (0.14 ± 0.11 mm) was noted but without significance (P > 0.05). Within the limits of this study, modified OSFE with CGF application and simultaneous short implant placement could yield predictable clinical results for severely atrophic maxilla with RBH of 2-4 mm. PMID:27250556

  4. Inlay osteotome sinus floor elevation with concentrated growth factor application and simultaneous short implant placement in severely atrophic maxilla

    PubMed Central

    Chen, Yonghui; Cai, Zhiyu; Zheng, Dingguo; Lin, Pei; Cai, Yahua; Hong, Shuxin; Lai, Yiwei; Wu, Dong

    2016-01-01

    Sinus floor elevation with simultaneous implant placement in severely atrophic maxilla is challenging. The aim of this retrospective study was to evaluate the short-term performance of modified osteotome sinus floor elevation (OSFE) with concentrated growth factor (CGF) application and concurrent placement of a short implant in cases with residual bone height (RBH) of 2–4 mm. Twenty-five short implants were installed in 16 patients with mean RBH of 3.23 mm using modified OSFE with CGFs from January 2012 to April 2014. Postoperatively, the implants were clinically evaluated, and vertical bone gain (VBG) was measured using cone beam computed tomography. The mean duration of follow-up was 19.88 months (12–32 months). All the implants were stable with an overall survival rate of 100%. The mean VBG immediately after surgery was 9.21 mm. Six months later, significant reduction of alveolar bone height (2.90 ± 0.22 mm) was found (P < 0.05). During the second 6-month period, further alveolar bone resorption (0.14 ± 0.11 mm) was noted but without significance (P > 0.05). Within the limits of this study, modified OSFE with CGF application and simultaneous short implant placement could yield predictable clinical results for severely atrophic maxilla with RBH of 2–4 mm. PMID:27250556

  5. Glucose Evokes Rapid Ca2+ and Cyclic AMP Signals by Activating the Cell-Surface Glucose-Sensing Receptor in Pancreatic β-Cells

    PubMed Central

    Nakagawa, Yuko; Nagasawa, Masahiro; Medina, Johan; Kojima, Itaru

    2015-01-01

    Glucose is a primary stimulator of insulin secretion in pancreatic β-cells. High concentration of glucose has been thought to exert its action solely through its metabolism. In this regard, we have recently reported that glucose also activates a cell-surface glucose-sensing receptor and facilitates its own metabolism. In the present study, we investigated whether glucose activates the glucose-sensing receptor and elicits receptor-mediated rapid actions. In MIN6 cells and isolated mouse β-cells, glucose induced triphasic changes in cytoplasmic Ca2+ concentration ([Ca2+]c); glucose evoked an immediate elevation of [Ca2+]c, which was followed by a decrease in [Ca2+]c, and after a certain lag period it induced large oscillatory elevations of [Ca2+]c. Initial rapid peak and subsequent reduction of [Ca2+]c were independent of glucose metabolism and reproduced by a nonmetabolizable glucose analogue. These signals were also blocked by an inhibitor of T1R3, a subunit of the glucose-sensing receptor, and by deletion of the T1R3 gene. Besides Ca2+, glucose also induced an immediate and sustained elevation of intracellular cAMP ([cAMP]c). The elevation of [cAMP]c was blocked by transduction of the dominant-negative Gs, and deletion of the T1R3 gene. These results indicate that glucose induces rapid changes in [Ca2+]c and [cAMP]c by activating the cell-surface glucose-sensing receptor. Hence, glucose generates rapid intracellular signals by activating the cell-surface receptor. PMID:26630567

  6. Effects of elevated atmospheric CO{sub 2} concentrations and water stress on field-grown maize

    SciTech Connect

    Surano, K.A.; Kercher, J.R.

    1993-10-01

    Global atmospheric carbon dioxide (CO{sub 2}) concentrations are continuing to increase and will probably double during the next century. The effects of such an increase are of global concern. Carbon dioxide-induced climate changes may result in reduced precipitation in major agricultural areas. The potential therefore exists for severe CO{sub 2}-induced water-stress effects on agriculture. This set of studies determined the effects of long-term elevated atmospheric CO{sub 2} concentrations and severe water stress on biomass production, evapotranspiration, water-use efficiency (WUE), water potential, photosynthesis, stomatal conductance, morphology and phenology of maize grown under field conditions. Plants were grown at one of four daytime mean CO{sub 2} concentrations (348, 431, 506 or 656 {mu}LL{sup {minus}1}) in open-top field exposure chambers and at one of two levels of available water (well-watered or 50% of well-watered). This report is organized into 4 chapters followed by appendices. Separate abstracts were prepared for each of the four chapters: (1) biomass production and water-use efficiency, (2) gas exchange and water potential, (3) morphology and phenology, and (4) and elemental analyses. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database.

  7. Effects of elevated CO sub 2 concentrations on glycolysis in intact Bartlett pear fruit. [Pyrus communis L

    SciTech Connect

    Kerbel, E.L.; Kader, A.A.; Romani, R.J. )

    1988-04-01

    Mature intact Bartlett pear fruit (Pyrus communis L.) were stored under a continuous flow of air or air + 10% CO{sub 2} for 4 days at 20{degree}C. Fruit kept under elevated CO{sub 2} concentrations exhibited reduced respiration (O{sub 2} consumption) and ethylene evolution rates, and remained firmer and greener than fruit stored in air. Protein content, fructose 1,6-bisphosphate levels, and ATP:phosphofructokinase and PPi:phosphofructokinase activities declined, while levels of fructose 6-phosphate and fructose 2,6-bisphosphate increased in fruit exposed to air + 10% CO{sub 2}. These results are discussed in light of a possible inhibitory effect of CO{sub 2} at the site of action of both phosphofructokinases in the glycolytic pathway, which could account, at least in part, for the observed reduction in respiration.

  8. Mesozooplankton community development at elevated CO2 concentrations: results from a mesocosm experiment in an Arctic fjord

    NASA Astrophysics Data System (ADS)

    Niehoff, B.; Schmithüsen, T.; Knüppel, N.; Daase, M.; Czerny, J.; Boxhammer, T.

    2013-03-01

    The increasing CO2 concentration in the atmosphere caused by burning fossil fuels leads to increasing pCO2 and decreasing pH in the world ocean. These changes may have severe consequences for marine biota, especially in cold-water ecosystems due to higher solubility of CO2. However, studies on the response of mesozooplankton communities to elevated CO2 are still lacking. In order to test whether abundance and taxonomic composition change with pCO2, we have sampled nine mesocosms, which were deployed in Kongsfjorden, an Arctic fjord at Svalbard, and were adjusted to eight CO2 concentrations, initially ranging from 185 μatm to 1420 μatm. Vertical net hauls were taken weekly over about one month with an Apstein net (55 μm mesh size) in all mesocosms and the surrounding fjord. In addition, sediment trap samples, taken every second day in the mesocosms, were analysed to account for losses due to vertical migration and mortality. The taxonomic analysis revealed that meroplanktonic larvae (Cirripedia, Polychaeta, Bivalvia, Gastropoda, and Decapoda) dominated in the mesocosms while copepods (Calanus spp., Oithona similis, Acartia longiremis and Microsetella norvegica) were found in lower abundances. In the fjord copepods prevailed for most of our study. With time, abundance and taxonomic composition developed similarly in all mesocosms and the pCO2 had no significant effect on the overall community structure. Also, we did not find significant relationships between the pCO2 level and the abundance of single taxa. Changes in heterogeneous communities are, however, difficult to detect, and the exposure to elevated pCO2 was relatively short. We therefore suggest that future mesocosm experiments should be run for longer periods.

  9. PERFORMANCE AND SERUM GLUCOSE, INSULIN, IGF-1, AND NEFA CONCENTRATIONS OF CALVES NURSING BEEF COWS CONSUMING HIGH-LINOLEATE OR HIGH-OLEATE SAFFLOWER SEED SUPPLEMENTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Three-year-old Angus ' Gelbvieh beef cows nutritionally managed to achieve a BCS of 4 or 6 at parturition were used in a 2-yr experiment (n = 36/yr) to determine the effects of dietary lipid supplementation on suckling calf ADG and calf serum concentrations of glucose, insulin, IGF-1, and NEFA. Beg...

  10. DEVELOPMENTAL CHANGES OF PLASMA INSULIN, GLUCAGON, INSULIN-LIKE GROWTH FACTORS, THYROID HORMONES AND GLUCOSE CONCENTRATIONS IN CHICK EMBRYOS AND HATCHED CHICKS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The developmental hormonal changes in Cobb 500 chick embryos and hatched chicks were determined by measuring plasma insulin, glucagon, IGF-I, IGF-II, triiodothyronine, thyroxine, and glucose concentrations at different ages of chick embryos and hatched chicks. Plasma samples were obtained daily fro...

  11. Increased nitrate availability in the soil of a mixed mature temperate forest subjected to elevated CO2 concentration (canopy FACE)

    NASA Astrophysics Data System (ADS)

    Schleppi, Patrick; Inga, Bucher-Wallin; Frank, Hagedorn; Christian, Körner

    2013-04-01

    In a mature temperate forest in Hofstetten, Switzerland, deciduous tree canopies were subjected to a free-air CO2 enrichment (FACE) for a period of eight years. The effect of this treatment on the availability of nitrogen (N) in the soil was assessed along three transects across the experimental area, one under Fagus sylvatica, one under Quercus robur and Q. petraea and one under Carpinus betulus. Nitrate, ammonium and dissolved organic N (DON) were analysed in soil solution obtained with suction cups. Nitrate and ammonium were also captured in buried ion-exchange resin bags. These parameters were related to the local intensity of the FACE treatment as measured from the 13C depletion of dissolved inorganic carbon in the soil solution, because the CO2 used for the treatment was depleted in 13C (Schleppi et al., 2012). Over the eight years of the experiment, the CO2 enrichment reduced DON concentrations, did not affect ammonium, but induced higher nitrate concentrations, both in soil solution and in resin bags. In the nitrate captured in the resin bags, the natural abundance of the isotope 15N strongly increased. This indicates that the CO2 enrichment accelerated net nitrification, probably as an effect of the higher soil moisture resulting from the reduced transpiration of the CO2-enriched trees. It is also possible that N mineralisation was enhanced by root exudates (priming effect) or that the uptake of inorganic N by these trees decreased slightly as the result of a reduced N demand for fine root growth. In this mature deciduous forest we did not observe any progressive N limitation due to elevated atmospheric CO2 concentrations; on the contrary, we observed an enhanced N availability over the eight years of our measurements. This may, together with the global warming projected, exacerbate problems related to N saturation and nitrate leaching, although it is uncertain how long the observed trends will last in the future. Following the experiment with deciduous

  12. The survival of cultured mouse cerebellar granule cells is not dependent on elevated potassium-ion concentration.

    PubMed

    Mogensen, H S; Hack, N; Balázs, R; Jørgensen, O S

    1994-08-01

    The effects of K(+)-induced membrane depolarization were studied on the survival and biochemical parameters in mouse and rat cerebellar granule cells grown in micro-well cultures. Cell numbers were determined by estimating DNA content using the Hoechst 33258 fluorochrome binding assay. DNA from degenerated cells was removed by prior DNAase treatment. These DNA estimates of cell numbers were comparable with values obtained by direct counting of fluorescein diacetate-stained viable cells. In agreement with previous studies, the survival of rat granule cells was promoted by increasing the concentration of K+ in the medium from 5 to 25 mM throughout a 7-day culture period. In contrast, mouse granule cells survived in culture containing 'low' K+ (5 or 10 mM), as well as in the presence of 'high' K+ (25 mM). On the other hand, several biochemical parameters in mouse granule cells were markedly increased by cultivation in 'high' as compared with 'low' K(+)-containing media, demonstrated by increased fluorescein diacetate esterase activity, enhanced rate of NADPH-dependent tetrazolium reduction, augmented 2-deoxy-D-glucose accumulation and increased N-methyl-D-aspartate-evoked 45Ca2+ influx. It was concluded that although cultivation in 'high' K+ promotes biochemical differentiation in mouse cerebellar granule cells, these cells differ from their rat counterparts in that they do not develop a survival requirement for K(+)-induced membrane depolarization. PMID:7529458

  13. Effect of elevated atmospheric CO2 concentration on soil CO2 and N2O effluxes in a loess grassland

    NASA Astrophysics Data System (ADS)

    Cserhalmi, Dóra; Balogh, János; Papp, Marianna; Horváth, László; Pintér, Krisztina; Nagy, Zoltán

    2014-05-01

    Increasing atmospheric CO2 concentration proved to be the primary factor causing global climate change. Exposition systems to study the response to increasing CO2 levels by the terrestrial vegetation include the open top chamber (OTC) exposition system, also used in this study. Response of biomass growth and ecophysiological variables (e.g. emission of greenhouse gases (CO2, N2O) from the soil) to elevated atmospheric CO2 concentration were investigated in the OTC station, located in the Botanical Garden of the Szent István University, Gödöllő , Hungary. Loess grassland (Salvio nemorosae - Festucetum rupicolae) monoliths were studied in OTCs with target air CO2 concentration of 600 mikromol.mol-1 in 3 chambers. The chamber-effect (shade effect of the side of the chambers) was measured in 3 control chambers under present CO2 level. This management was compared to 3 free air parcels under the natural conditions. Changes of soil temperature and soil water content were recorded in each treatment, while PAR, air temperature, precipitation, wind velocity and humidity were measured by a micrometeorological station. Plant biomass was cut down to 5 cm height once a year. Leaf area index (LAI) was estimated weekly from ceptometer measurements, soil CO2 and N2O effluxes were also measured weekly during the growing period and less frequently during the rest of the year. Soil water content in the upper 30 cm of the soil was lower in the chambers by 3 % (v/v) in average than in the field plots. Soil temperature in the chambers at 3 cm depth was 1.5oC lower than in the free air parcels probably due to the shading effect of the larger biomass in the chambers. In the chambers (both the high CO2 and control ones) biomass values (536.59 ±222.43 gm-2) were higher than in the free parcels (315.67 ±73.36 gm-2). Average LAI was also higher (3.07 ± 2.78) in the chambers than in the free air treatment (2.08 ± 1.95). Soil respiration values in the high CO2 treatment was higher in

  14. The effects of elevated CO2 concentration on competitive interaction between aceticlastic and syntrophic methanogenesis in a model microbial consortium

    PubMed Central

    Kato, Souichiro; Yoshida, Rina; Yamaguchi, Takashi; Sato, Tomoyuki; Yumoto, Isao; Kamagata, Yoichi

    2014-01-01

    Investigation of microbial interspecies interactions is essential for elucidating the function and stability of microbial ecosystems. However, community-based analyses including molecular-fingerprinting methods have limitations for precise understanding of interspecies interactions. Construction of model microbial consortia consisting of defined mixed cultures of isolated microorganisms is an excellent method for research on interspecies interactions. In this study, a model microbial consortium consisting of microorganisms that convert acetate into methane directly (Methanosaeta thermophila) and syntrophically (Thermacetogenium phaeum and Methanothermobacter thermautotrophicus) was constructed and the effects of elevated CO2 concentrations on intermicrobial competition were investigated. Analyses on the community dynamics by quantitative RT-PCR and fluorescent in situ hybridization targeting their 16S rRNAs revealed that high concentrations of CO2 have suppressive effects on the syntrophic microorganisms, but not on the aceticlastic methanogen. The pathways were further characterized by determining the Gibbs free energy changes (ΔG) of the metabolic reactions conducted by each microorganism under different CO2 concentrations. The ΔG value of the acetate oxidation reaction (T. phaeum) under high CO2 conditions became significantly higher than -20 kJ per mol of acetate, which is the borderline level for sustaining microbial growth. These results suggest that high concentrations of CO2 undermine energy acquisition of T. phaeum, resulting in dominance of the aceticlastic methanogen. This study demonstrates that investigation on model microbial consortia is useful for untangling microbial interspecies interactions, including competition among microorganisms occupying the same trophic niche in complex microbial ecosystems. PMID:25400628

  15. Agmatine protects Müller cells from high-concentration glucose-induced cell damage via N-methyl-D-aspartic acid receptor inhibition.

    PubMed

    Han, Ning; Yu, Li; Song, Zhidu; Luo, Lifu; Wu, Yazhen

    2015-07-01

    Neural injury is associated with the development of diabetic retinopathy. Müller cells provide structural and metabolic support for retinal neurons. High glucose concentrations are known to induce Müller cell activity. Agmatine is an endogenous polyamine, which is enzymatically formed in the mammalian brain and has exhibited neuroprotective effects in a number of experimental models. The aims of the present study were to investigate whether agmatine protects Müller cells from glucose-induced damage and to explore the mechanisms underlying this process. Lactate dehydrogenase activity and tumor necrosis factor-α mRNA expression were significantly reduced in Müller cells exposed to a high glucose concentration, following agmatine treatment, compared with cells not treated with agmatine. In addition, agmatine treatment inhibited glucose-induced Müller cell apoptosis, which was associated with the regulation of Bax and Bcl-2 expression. Agmatine treatment suppressed glucose-induced phosphorylation of mitogen-activated protein kinase (MAPK) protein in Müller cells. The present study demonstrated that the protective effects of agmatine on Müller cells were inhibited by N-methyl-D-aspartic acid (NMDA). The results of the present study suggested that agmatine treatment protects Müller cells from high-concentration glucose-induced cell damage. The underlying mechanisms may relate to the anti-inflammatory and antiapoptotic effects of agmatine, as well as to the inhibition of the MAPK pathway, via NMDA receptor suppression. Agmatine may be of use in the development of novel therapeutic approaches for patients with diabetic retinopathy. PMID:25816073

  16. Dietary Sodium Reduction Does Not Affect Circulating Glucose Concentrations in Fasting Children or Adults: Findings from a Systematic Review and Meta-Analysis1234

    PubMed Central

    Patel, Sheena M; Cobb, Paul; Saydah, Sharon; Zhang, Xuanping; de Jesus, Janet M; Cogswell, Mary E

    2015-01-01

    Background: Although evidence shows that reduced sodium intake lowers blood pressure, some studies suggest that sodium reduction may adversely affect insulin resistance and glucose tolerance. Objectives: The objectives were to assess the effects of sodium reduction on glucose tolerance, evaluate strengths and weaknesses of the relevant scientific literature, and provide direction for future research. Methods: We searched The Cochrane Library, MEDLINE, EMBASE, CINAHL, and Web of Science through August 2014. Both randomized and nonrandomized intervention trials were included in our meta-analyses. The effects of sodium reduction on glucose tolerance were evaluated in 37 articles, but because of a lack of comparable data, 8 trials were excluded from the meta-analyses. Results: Participants were 10–79 y old, either primarily healthy or with hypertension. In meta-analyses of 20 randomized, crossover trials (n = 504 participants) and 9 nonrandomized crossover trials (n = 337), circulating glucose concentrations of fasting participants were not affected by reduction in sodium intake. In contrast, in meta-analyses of 19 of the 20 randomized, crossover trials (n = 494), fasting insulin concentrations were 9.53 pmol/L higher (95% CI: 5.04, 14.02 pmol/L higher) with sodium reduction. In 9 nonrandomized trials (n = 337), fasting insulin did not differ with reduced sodium intake. Results differed little when the analyses were restricted to studies with a low risk of bias and duration of ≥7 d. Conclusions: This meta-analysis revealed no evidence that, in trials with a short intervention and large reductions in sodium, circulating glucose concentrations differed between groups. Recommendations for future studies include extending intervention durations, ensuring comparability of groups at baseline through randomization, and assessing sodium intakes relevant to population sodium reduction. In addition, analyses on other metabolic variables were limited because of the number of

  17. Twenty-four Hour Endocrine and Metabolic Profiles Following Consumption of High Fructose Corn Syrup-, Sucrose- Fructose-, and Glucose-Sweetened Beverages with Meals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have reported that compared with glucose-sweetened beverages, consuming fructose-sweetened beverages with meals results in lower 24-h circulating glucose, insulin and leptin concentrations, and elevated triacylglycerol (TG). However, pure fructose and glucose are not commonly used as sweeteners. ...

  18. Photosynthetic CO2 uptake in seedlings of two tropical tree species exposed to oscillating elevated concentrations of CO2.

    PubMed

    Holtum, Joseph A M; Winter, Klaus

    2003-11-01

    Do short-term fluctuations in CO2 concentrations at elevated CO2 levels affect net CO2 uptake rates of plants? When exposed to 600 microl CO2 l(-1), net CO2 uptake rates in shoots or leaves of seedlings of two tropical C3 tree species, teak (Tectona grandis L. f.) and barrigon [Pseudobombax septenatum (Jacq.) Dug.], increased by 28 and 52% respectively. In the presence of oscillations with half-cycles of 20 s, amplitude of ca. 170 microl CO2 l(-1) and mean of 600 microl CO2 l(-1), the stimulation in net CO2 uptake by the two species was reduced to 19 and 36%, respectively, i.e. the CO2 stimulation in photosynthesis associated with a change in exposure from 370 to 600 microl CO2 l(-1) was reduced by a third in both species. Similar reductions in CO2-stimulated net CO2 uptake were observed in T. grandis exposed to 40-s oscillations. Rates of CO2 efflux in the dark by whole shoots of T. grandis decreased by 4.8% upon exposure of plants grown at 370 microl CO2 l(-1) to 600 microl CO2 l(-1). The potential implications of the observations on CO2 oscillations and dark respiration are discussed in the context of free-air CO2 enrichment (FACE) systems in which short-term fluctuations of CO2 concentration are a common feature. PMID:12905026

  19. Seasonal and species-specific response of VOC emissions by Mediterranean woody plant to elevated ozone concentrations

    NASA Astrophysics Data System (ADS)

    Llusià, J.; Peñuelas, J.; Gimeno, B. S.

    Although certain factors controlling plant emission rates of volatile organic compounds (VOCs) are reasonably well understood, the influence of elevated ozone concentrations as abiotic stress is mostly unknown. Therefore, we studied the effects of ozone concentrations on seasonal biogenic volatile organic compound (BVOC) emissions by different Mediterranean plant species in open top chambers (OTC). Three ozone treatments were established: filtered air (F), non-filtered air (NF), and fumigated air (NF+) adding 40 nl l -1 of ozone over NF. We studied the response of VOC emission in saplings of four Mediterranean woody plant species and subspecies: Ceratonia siliqua L., Olea europaea L., Quercus ilex spp. ilex L., and Quercus ilex spp. rotundifolia L. as representative of natural Mediterranean vegetation. No visible symptoms were detected on the leaves. No significant effect was found on net photosynthetic rates or stomatal conductance except for an increase in net photosynthetic rates in Quercus ilex ilex in spring and summer and an overall slight increase in Quercus ilex rotundifolia. Emissions of the total VOCs from Ceratonia siliqua in summer, and from Olea europaea and Quercus ilex rotundifolia in spring increased in ozone fumigated OTC in comparison with F or NF OTC. Decreased emissions were found in Quercus ilex rotundifolia in summer. There were no significant differences between ozone fumigation treatments for the other plant species and seasons. When considering particular VOCs, the results were also variable among species and time of the year. While α-pinene emissions decreased with ozone fumigation in Olea europaea, α-pinene and limonene emissions increased in Quercus ilex ilex. The responses of these particular VOCs did not always match the responses of total VOCs. In spite of this strong variability, when considering overall annual data for all species and seasons, there were increased net photosynthetic rates (37%) and limonene (95%) and total VOC (45

  20. Effects of elevated CO2 concentration on growth, photosynthetic characteristics and yield of chufa (Cyperus esculentus L.) in Lunar Palace 1

    NASA Astrophysics Data System (ADS)

    Liu, Guanghui; Liu, Hui; Liu, Hong; Wang, Minjuan; Fu, Yuming; Shao, Lingzhi; Dong, Chen; Yu, Juan

    Elevated CO2 concentration is a common phenomenon in spaceflight environment. Effects of elevated CO2 concentration within short- and long-term on growth, photosynthetic characteristics and yield of chufa (Cyperus esculentus L.) are examined during 90 days in Lunar Palace 1. Elevated CO2 within a short-term induces a large increase in photosynthesis in chufa, long-term expose in elevated CO2 can lead to a smaller increase resulting from the inhibition of photosynthesis. It is indicated that the increased net photosynthesis per unit leaf area at elevated CO2 concentration come from an inhibition of photorespiration and an Increase of photosynthesis substrate. Low stomatal conductance reduced the transpiration. Effects of high CO2 concentration to the growth of whole plants is the main point of this research. The probable CO2 concentration affecting chufa growth is evaluated in Lunar Palace 1, and the mechanisms will be revealed. The proper CO2 concentration for highest production of chufa in spaceflight environment will be figured out, which plays an important role in plant cultivation supporting spaceflight tasks.

  1. Tolerance of allogromiid Foraminifera to severely elevated carbon dioxide concentrations: Implications to future ecosystem functioning and paleoceanographic interpretations

    SciTech Connect

    Bernhard, Joan M.; Mollo-Christensen, Elizabeth; Eisenkolb, Nadine; Starczak, Victoria R.

    2009-02-01

    Increases in the partial pressure of carbon dioxide (pCO2) in the atmosphere will significantly affect a wide variety of terrestrial fauna and flora. Because of tight atmospheric oceanic coupling, shallow-water marine species are also expected to be affected by increases in atmospheric carbon dioxide concentrations. One proposed way to slow increases in atmospheric pCO2 is to sequester CO2 in the deep sea. Thus, over the next few centuries marine species will be exposed to changing seawater chemistry caused by ocean atmospheric exchange and/or deep-ocean sequestration. This initial case study on one allogromiid foraminiferal species (Allogromia laticollaris) was conducted to begin to ascertain the effect of elevated pCO2 on benthic Foraminifera, which are a major meiofaunal constituent of shallow- and deep-water marine communities. Cultures of this thecate foraminiferan protist were used for 10-14-day experiments. Experimental treatments were executed in an incubator that controlled CO2 (15000; 30 000; 60 000; 90 000; 200 000 ppm), temperature and humidity; atmospheric controls (i.e., ~375 ppm CO2) were executed simultaneously. Although the experimental elevated pCO2 values are far above foreseeable surface water pCO2, they were selected to represent the spectrum of conditions expected for the benthos if deep-sea CO2 sequestration becomes a reality. Survival was assessed in two independent ways: pseudopodial presence/absence and measurement of adenosine triphosphate (ATP), which is an indicator of cellular energy. Substantial proportions of A. laticollaris populations survived 200 000 ppm CO2 although the mean of the median [ATP] of survivors was statistically lower for this treatment than for that of atmospheric control specimens. After individuals that had been incubated in 200 000 ppm CO2 for 12 days were transferred to atmospheric conditions for ~24 h, the [ATP] of live specimens (survivors) approximated those of the comparable atmospheric control treatment

  2. The level of menadione redox-cycling in pancreatic β-cells is proportional to the glucose concentration: Role of NADH and consequences for insulin secretion

    SciTech Connect

    Heart, Emma; Palo, Meridith; Womack, Trayce; Smith, Peter J.S.; Gray, Joshua P.

    2012-01-15

    Pancreatic β-cells release insulin in response to elevation of glucose from basal (4–7 mM) to stimulatory (8–16 mM) levels. Metabolism of glucose by the β-cell results in the production of low levels of reactive oxygen intermediates (ROI), such as hydrogen peroxide (H{sub 2}O{sub 2}), a newly recognized coupling factor linking glucose metabolism to insulin secretion. However, high and toxic levels of H{sub 2}O{sub 2} inhibit insulin secretion. Menadione, which produces H{sub 2}O{sub 2} via redox cycling mechanism in a dose-dependent manner, was investigated for its effect on β-cell metabolism and insulin secretion in INS-1 832/13, a rat β-cell insulinoma cell line, and primary rodent islets. Menadione-dependent redox cycling and resulting H{sub 2}O{sub 2} production under stimulatory glucose exceeded several-fold those reached at basal glucose. This was paralleled by a differential effect of menadione (0.1–10 μM) on insulin secretion, which was enhanced at basal, but inhibited at stimulatory glucose. Redox cycling of menadione and H{sub 2}O{sub 2} formation was dependent on glycolytically-derived NADH, as inhibition of glycolysis and application of non-glycogenic insulin secretagogues did not support redox cycling. In addition, activity of plasma membrane electron transport, a system dependent in part on glycolytically-derived NADH, was also inhibited by menadione. Menadione-dependent redox cycling was sensitive to the NQO1 inhibitor dicoumarol and the flavoprotein inhibitor diphenylene iodonium, suggesting a role for NQO1 and other oxidoreductases in this process. These data may explain the apparent dichotomy between the stimulatory and inhibitory effects of H{sub 2}O{sub 2} and menadione on insulin secretion. -- Highlights: ► Menadione stimulation or inhibition of insulin secretion is dependent upon applied glucose levels. ► Menadione-dependent H{sub 2}O{sub 2} production is proportional to applied glucose levels. ► Quinone-mediated redox cycling

  3. Systemic Concentrations of Short Chain Fatty Acids Are Elevated in Salmonellosis and Exacerbation of Familial Mediterranean Fever

    PubMed Central

    Ktsoyan, Zhanna A.; Mkrtchyan, Mkhitar S.; Zakharyan, Magdalina K.; Mnatsakanyan, Armine A.; Arakelova, Karine A.; Gevorgyan, Zaruhi U.; Sedrakyan, Anahit M.; Hovhannisyan, Alvard I.; Arakelyan, Arsen A.; Aminov, Rustam I.

    2016-01-01

    Gut microbiota-produced short chain fatty acids (SCFAs) play an important role in the normal human metabolism and physiology. Although the gradients of SCFAs from the large intestine, where they are largely produced, to the peripheral blood as well as the main routes of SCFA metabolism by different organs are known well for the healthy state, there is a paucity of information regarding how these are affected in disease. In particular, how the inflammation caused by infection or autoinflammatory disease affect the concentration of SCFAs in the peripheral venous blood. In this work, we revealed that diseases caused either by infectious agents (two Salmonella enterica serovars, S. Enteritidis, and S. Typhimurium) or by the exacerbation of an autoinflammatory disease, familial Mediterranean fever (FMF), both result in a significantly elevated systemic concentration of SCFAs. In the case of salmonellosis the concentration of SCFAs in peripheral blood was significantly and consistently higher, from 5- to 20-fold, compared to control. In the case of FMF, however, a significant increase of SCFAs in the peripheral venous blood was detected only in the acute phase of the disease, with a lesser impact in remission. It seems counterintuitive that the dysbiotic conditions, with a reduced number of gut microorganisms, produce such an effect. This phenomenon, however, must be appraised within the context of how the inflammatory diseases affect the normal physiology. We discuss a number of factors that may contribute to the “leak” and persistence of gut-produced SCFAs into the systemic circulation in infectious and autoinflammatory diseases. PMID:27252692

  4. Alterations in blood glucose and plasma glucagon concentrations during deep brain stimulation in the shell region of the nucleus accumbens in rats

    PubMed Central

    Diepenbroek, Charlene; van der Plasse, Geoffrey; Eggels, Leslie; Rijnsburger, Merel; Feenstra, Matthijs G. P.; Kalsbeek, Andries; Denys, Damiaan; Fliers, Eric; Serlie, Mireille J.; la Fleur, Susanne E.

    2013-01-01

    Deep brain stimulation (DBS) of the nucleus accumbens (NAc) is an effective therapy for obsessive compulsive disorder (OCD) and is currently under investigation as a treatment for eating disorders. DBS of this area is associated with altered food intake and pharmacological treatment of OCD is associated with the risk of developing type 2 diabetes. Therefore we examined if DBS of the NAc-shell (sNAc) influences glucose metabolism. Male Wistar rats were subjected to DBS, or sham stimulation, for a period of 1 h. To assess the effects of stimulation on blood glucose and glucoregulatory hormones, blood samples were drawn before, during and after stimulation. Subsequently, all animals were used for quantitative assessment of Fos immunoreactivity in the lateral hypothalamic area (LHA) using computerized image analysis. DBS of the sNAc rapidly increased plasma concentrations of glucagon and glucose while sham stimulation and DBS outside the sNAc were ineffective. In addition, the increase in glucose was dependent on DBS intensity. In contrast, the DBS-induced increase in plasma corticosterone concentrations was independent of intensity and region, indicating that the observed DBS-induced metabolic changes were not due to corticosterone release. Stimulation of the sNAc with 200 μA increased Fos immunoreactivity in the LHA compared to sham or 100 μA stimulated animals. These data show that DBS of the sNAc alters glucose metabolism in a region- and intensity- dependent manner in association with neuronal activation in the LHA. Moreover, these data illustrate the need to monitor changes in glucose metabolism during DBS-treatment of OCD patients. PMID:24339800

  5. Effects of glucagon and insulin on plasma glucose, triglyceride, and triglyceride-rich lipoprotein concentrations in laying hens fed diets containing different types of fats.

    PubMed

    Pál, L; Grossmann, R; Dublecz, K; Husvéth, F; Wagner, L; Bartos, A; Kovács, G

    2002-11-01

    The influence of dietary fat supplementations differing in the ratio of n-6 to n-3 polyunsaturated fatty acids (PUFA) on the effects of glucagon and insulin on plasma glucose, triglyceride (TG), and TG-rich lipoprotein concentrations was investigated in laying hens. Birds were fed either a low-fat control diet (LF) or diets supplemented with 4% pumpkin seed oil (PO; rich in n-6 PUFA) or 4% cod liver oil (CO; rich in n-3 PUFA). After 4 wk feeding of the experimental diets, hens were implanted with wing vein catheters and injected with porcine glucagon (20 microg/kg BW) and porcine insulin (0.5 IU/kg BW), 2 to 5 h after oviposition. Plasma glucose, TG, and TG-rich lipoprotein concentrations were determined from 10 min pre-injection to 60 min post-injection. PO diet resulted in a prolonged plasma glucose response to glucagon administration and altered hypoglycemic response to insulin. However, CO diet did not influence plasma glucose response to either glucagon or insulin administration compared to LF diet. The effects of glucagon and insulin on plasma TG and TG-rich lipoproteins were similar for all diets regardless of the amount or type of fat. The results suggest that feeding dietary fats with high n-6 to n-3 PUFA ratio alters the glucagon and insulin sensitivity of plasma glucose in laying hens. Fats rich in n-3 PUFA seem to have no influence on the plasma glucose response to glucagon and insulin. PMID:12455597

  6. Alterations in blood glucose and plasma glucagon concentrations during deep brain stimulation in the shell region of the nucleus accumbens in rats.

    PubMed

    Diepenbroek, Charlene; van der Plasse, Geoffrey; Eggels, Leslie; Rijnsburger, Merel; Feenstra, Matthijs G P; Kalsbeek, Andries; Denys, Damiaan; Fliers, Eric; Serlie, Mireille J; la Fleur, Susanne E

    2013-01-01

    Deep brain stimulation (DBS) of the nucleus accumbens (NAc) is an effective therapy for obsessive compulsive disorder (OCD) and is currently under investigation as a treatment for eating disorders. DBS of this area is associated with altered food intake and pharmacological treatment of OCD is associated with the risk of developing type 2 diabetes. Therefore we examined if DBS of the NAc-shell (sNAc) influences glucose metabolism. Male Wistar rats were subjected to DBS, or sham stimulation, for a period of 1 h. To assess the effects of stimulation on blood glucose and glucoregulatory hormones, blood samples were drawn before, during and after stimulation. Subsequently, all animals were used for quantitative assessment of Fos immunoreactivity in the lateral hypothalamic area (LHA) using computerized image analysis. DBS of the sNAc rapidly increased plasma concentrations of glucagon and glucose while sham stimulation and DBS outside the sNAc were ineffective. In addition, the increase in glucose was dependent on DBS intensity. In contrast, the DBS-induced increase in plasma corticosterone concentrations was independent of intensity and region, indicating that the observed DBS-induced metabolic changes were not due to corticosterone release. Stimulation of the sNAc with 200 μA increased Fos immunoreactivity in the LHA compared to sham or 100 μA stimulated animals. These data show that DBS of the sNAc alters glucose metabolism in a region- and intensity- dependent manner in association with neuronal activation in the LHA. Moreover, these data illustrate the need to monitor changes in glucose metabolism during DBS-treatment of OCD patients. PMID:24339800

  7. Effects of isoleucine on glucose uptake through the enhancement of muscular membrane concentrations of GLUT1 and GLUT4 and intestinal membrane concentrations of Na+/glucose co-transporter 1 (SGLT-1) and GLUT2.

    PubMed

    Zhang, Shihai; Yang, Qing; Ren, Man; Qiao, Shiyan; He, Pingli; Li, Defa; Zeng, Xiangfang

    2016-08-01

    Knowledge of regulation of glucose transport contributes to our understanding of whole-body glucose homoeostasis and human metabolic diseases. Isoleucine has been reported to participate in regulation of glucose levels in many studies; therefore, this study was designed to examine the effect of isoleucine on intestinal and muscular GLUT expressions. In an animal experiment, muscular GLUT and intestinal GLUT were determined in weaning pigs fed control or isoleucine-supplemented diets. Supplementation of isoleucine in the diet significantly increased piglet average daily gain, enhanced GLUT1 expression in red muscle and GLUT4 expression in red muscle, white muscle and intermediate muscle (P<0·05). In additional, expressions of Na+/glucose co-transporter 1 and GLUT2 were up-regulated in the small intestine when pigs were fed isoleucine-supplemented diets (P<0·05). C2C12 cells were used to examine the expressions of muscular GLUT and glucose uptake in vitro. In C2C12 cells supplemented with isoleucine in the medium, cellular 2-deoxyglucose uptake was increased (P<0·05) through enhancement of the expressions of GLUT4 and GLUT1 (P<0·05). The effect of isoleucine was greater than that of leucine on glucose uptake (P<0·05). Compared with newborn piglets, 35-d-old piglets have comparatively higher GLUT4, GLUT2 and GLUT5 expressions. The results of this study demonstrated that isoleucine supplementation enhanced the intestinal and muscular GLUT expressions, which have important implications that suggest that isoleucine could potentially increase muscle growth and intestinal development by enhancing local glucose uptake in animals and human beings. PMID:27464458

  8. Elevated non-esterified fatty acid concentrations hamper bovine oviductal epithelial cell physiology in three different in vitro culture systems.

    PubMed

    Jordaens, L; Arias-Alvarez, M; Pintelon, I; Thys, S; Valckx, S; Dezhkam, Y; Bols, P E J; Leroy, J L M R

    2015-10-01

    Elevated non-esterified fatty acids (NEFAs) have been recognized as an important link between lipolytic metabolic conditions and impaired fertility in high-yielding dairy cows. However, NEFA effects on the oviductal micro-environment currently remain unknown. We hypothesize that elevated NEFAs may contribute to the complex pathology of subfertility by exerting a negative effect on bovine oviductal epithelial cell (BOEC) physiology. Therefore, the objectives of this study were to elucidate direct NEFA effects on BOEC physiology in three different in vitro cell culture systems. Bovine oviductal epithelial cells (four replicates) were mechanically isolated, pooled, and cultured as conventional monolayers, as explants, and in a polarized cell culture system with Dulbecco's modified Eagle's medium/F12-based culture medium. Bovine oviductal epithelial cells were exposed to an NEFA mixture of oleic, stearic, and palmitic acids for 24 hours at both physiological and pathologic concentrations. A control (0 μM NEFA) and a solvent control (0 μM NEFA + 0.45% ethanol) group were implemented. Bovine oviductal epithelial cells physiology was assessed by means of cell number and viability, a sperm binding assay, transepithelial electric resistance (TER), and a wound-healing assay. Bovine oviductal epithelial cell morphology was assessed by scanning electron microscopy on cell polarity, presence of microvilli and cilia, and monolayer integrity. Bovine oviductal epithelial cell number was negatively affected by increasing NEFAs, however, cell viability was not. Sperm binding affinity significantly decreased with increasing NEFAs and tended (P = 0.051) to be more affected by the direction of NEFA exposure in the polarized cell culture system. The absolute TER increase after NEFA exposure in the control (110 ± 11 Ω.cm(2)) was significantly higher than that in all the other treatments and was also different depending on the exposure side. Bidirectional exposed monolayers were even

  9. Glucose enhances insulin promoter activity in MIN6 beta-cells independently of changes in intracellular Ca2+ concentration and insulin secretion.

    PubMed Central

    Kennedy, H J; Rafiq, I; Pouli, A E; Rutter, G A

    1999-01-01

    Recent studies have suggested that glucose may activate insulin gene transcription through increases in intracellular Ca(2+) concentration, possibly acting via the release of stored insulin. We have investigated this question by dynamic photon-counting imaging of insulin- and c-fos-promoter-firefly luciferase reporter construct activity. Normalized to constitutive viral promoter activity, insulin promoter activity in MIN6 beta-cells was increased 1.6-fold after incubation at 30 mM compared with 3 mM glucose, but was unaltered at either glucose concentration by the presence of insulin (100 nM) or the Ca(2+) channel inhibitor, verapamil (100 microM). Increases in intracellular [Ca(2+)] achieved by plasma membrane depolarization with KCl failed to enhance either insulin or c-fos promoter activity in MIN6 cells, but increased c-fos promoter activity 5-fold in AtT20 cells. Together, these results demonstrate that glucose can exert a direct effect on insulin promoter activity in islet beta-cells, via a signalling pathway which does not require increases in intracellular [Ca(2+)] nor insulin release and insulin receptor activation. PMID:10455011

  10. Development of laboratory reference material: Soil 1. Baseline and highly elevated concentrations of metals and polycyclic aromatic hydrocarbons.

    PubMed

    Kupiec, K; Konieczka, P; Namieśnik, J

    2011-01-01

    Reference materials play a key part in systems of inspection and quality control of results of analytical measurements. The main limitation in using certified reference materials (CRM) is their high price, which results from the long and costly process of producing the reference material. An alternative to costly CRM materials is the employment of laboratory reference materials, particularly for interlaboratory control of measurement results and procedures. Under the auspices of the Chair of Analytical Chemistry at the Chemical Department of Gdansk University of Technology, research on the development of new reference materials is being conducted. At present, the research is aimed at producing a new laboratory reference material (LRM): 'Soil 1. Baseline and Highly Elevated Concentrations of Metals and Polycyclic Aromatic Hydrocarbons' - LRM soil 1. This paper presents the production stages of the developed laboratory reference material: acquisition of raw material from soil samples taken from the environment of the Tri-city (in Polish, Trójmiasto Gdansk, Sopot, Gdynia) bypass road, homogenization and subsequent dosage into appropriate containers, tests of homogeneity of sampled material within one container and between containers, based on the results of the determination of selected parameters (total carbon, content of optional metals - Hg, Fe, Cu Zn, Mn, Mg, water content, content of PAH-group analytes). The obtained results of homogeneity tests of the proposed future laboratory reference material have confirmed the homogeneity of soil samples within a container and between containers. Currently, interlaboratory tests are being carried out to determine the reference value. PMID:21473281

  11. Elevated temperatures increase leaf senescence and root secondary metabolite concentrations in the understory herb Panax quinquefolius (Araliaceae).

    PubMed

    Jochum, Gera M; Mudge, Kenneth W; Thomas, Richard B

    2007-05-01

    The response of understory species to elevated temperatures is not well understood but is important because these plants are highly sensitive to their growth conditions. Three-year-old plants of Panax quinquefolius, an understory herb endemic to the eastern deciduous forests of North America, were grown in a greenhouse at 25/20°C (day/night) or 30/25°C for one growing season and analyzed each month. Plants grown at high temperatures had an early onset of leaf senescence and therefore accumulated less carbon. From May to July, P. quinquefolius grown at high temperatures had decreased photosynthesis (52%), stomatal conductance (60%), and root and total biomass (33% and 28%, respectively) compared to plants grown at low temperatures. As P. quinquefolius prepared to overwinter, plants grown at high temperatures had less root biomass (53%) than plants in low temperatures. The amount of storage-root ginsenosides was unaffected by temperature, and differences in storage root size may explain why plants grown at high temperatures had greater concentrations of storage root ginsenosides (49%) than plants grown at low temperatures. Panax quinquefolius is clearly sensitive to a 5°C increase in temperature, and therefore other understory species may be negatively impacted by future increases in global temperature. PMID:21636451

  12. Investigating the Role of Plasma Glucose Concentration as a Phenotypic Marker for CYP2C9 Genetic Variants, in the Diabetic Population of Gujarat.

    PubMed

    Bhatt, D; Chauhan, N; Sharma, A; Dhawan, D; Bhatt, R V; Phatak, S; Padh, H

    2014-01-01

    The present study was aimed to investigate the role of plasma glucose concentration as a phenotypic marker and to study the frequency distribution of CYP2C9 genetic variants in Gujarat state diabetic population. One hundred and nine unrelated diabetes mellitus patients treated with sulfonylureas were genotyped for CYP2C9*2 and CYP2C9*3 alleles. Their pre- and posttreatment postprandial blood glucose levels were recorded and mean glucose drop per milligram of drug values were calculated and further used as an index for phenotypic correlation. The frequencies of CYP2C9*1, CYP2C9*2 and CYP2C9*3 alleles in the Gujarat state diabetic population were 0.84, 0.07 and 0.09, respectively. The distribution of CYP2C9*1/*1, CYP2C9*1/*2, CYP2C9*1/*3, CYP2C9*2/*2, CYP2C9*2/*3 and CYP2C9*3/*3 genotypes were 0.73, 0.08, 0.13, 0.0, 0.06 and 0.0, respectively. Patients with CYP2C9*1/*2 genotype did not show any significant difference in the mean glucose drop per milligram of drug values when compared with wild-type patients in glipizide-treatment group. Patients with CYP2C9*1/*3 genotype showed greater mean glucose drop per milligram of drug values than patients with CYP2C9*1/*1 wild-type genotype for both glipizide and glimepiride while patients with CYP2C9*2/*3 genotype showed greater drop than patients with CYP2C9*1/*1 genotype only in the glipizide-treatment group. The presence of CYP2C9*3 allele significantly affected plasma glucose drop per milligram of drug values in patients taking glipizide and glimepiride, while effects of CYP2C9*2 allele were insignificant. Further studies are needed to confirm the effects of CYP2C9*2 allele on plasma glucose drop per milligram of drug values. However, plasma glucose concentration is a complex physiological marker that cannot be used to establish perfect genotype-phenotype correlation. Hence studies exploring robust phenotypic markers must be initiated. PMID:24799741

  13. Mitogen-stimulated and rapamycin-sensitive glucose transporter 12 targeting and functional glucose transport in renal epithelial cells.

    PubMed

    Wilson-O'Brien, Amy L; Dehaan, Carrie L; Rogers, Suzanne

    2008-03-01

    We hypothesized that glucose transporter 12 (GLUT12) is involved in regulation of glucose flux in distal renal tubules in response to elevated glucose. We used the Madin-Darby canine kidney polarized epithelial cell model and neutralizing antibodies to analyze GLUT12 targeting and directional GLUT12-mediated glucose transport. At physiological glucose concentrations, GLUT12 was localized to a perinuclear position. High glucose and serum treatment resulted in GLUT12 localization to the apical membrane. This mitogen-stimulated targeting of GLUT12 was inhibited by rapamycin, the specific inhibitor of mammalian target of rapamycin (mTOR). The functional role of GLUT12 was also examined. We constructed a GLUT12 cDNA containing a c-Myc epitope tag in the fifth exofacial loop. Assays of glucose transport at the apical membrane were performed using Transwell filters. By comparing transport assays in the presence of neutralizing anti-c-Myc monoclonal antibody, we specifically measured GLUT12-mediated glucose transport at the apical surface. GLUT12-mediated glucose transport was mitogen dependent and rapamycin sensitive. Our results implicate mTOR signaling in a novel pathway of glucose transporter protein targeting and glucose transport. Activity of the mTOR pathway has been associated with diabetic kidney disease. Our results provide evidence for a link between GLUT12 protein trafficking, glucose transport and signaling molecules central to the control of metabolic disease processes. PMID:18039784

  14. Association Studies of Calcium-Sensing Receptor (CaSR) Polymorphisms with Serum Concentrations of Glucose and Phosphate, and Vascular Calcification in Renal Transplant Recipients

    PubMed Central

    Maréchal, Céline; Jadoul, Michel; Devuyst, Olivier; Thakker, Rajesh V.

    2015-01-01

    Background Cardiovascular disease is the major cause of death in renal transplant recipients (RTRs) and linked to arterial calcification. The calcium-sensing receptor (CaSR), a G-protein coupled receptor, plays a pivotal role in extracellular calcium homeostasis and is expressed in the intimal and medial layers of the arterial wall. We investigated whether common CASR gene variants are predictors for aortic and coronary artery calcification or influence risk factors such as serum calcium, phosphate and glucose concentrations in RTRs. Methods Two hundred and eighty four RTRs were investigated for associations between three CASR promoter region single nucleotide polymorphisms (SNPs) (rs115759455, rs7652589, rs1501899), three non-synonymous CASR coding region SNPs (A986S, R990G, Q1011E), and aortic and coronary artery calcium mass scores, cardiovascular outcomes and calcification risk factors that included serum phosphate, calcium, total cholesterol and glucose concentrations. Results Multivariate analysis revealed that RTRs homozygous for the minor allele (SS) of the A986S SNP, when compared to those homozygous for the major allele (AA), had raised serum glucose concentrations (8.7±5.4 vs. 5.7±2.1 mmol/L, P<0.05). In addition, RTRs who were heterozygous (CT) at the rs115759455 SNP, when compared to those homozygous for the major allele (CC), had higher serum phosphate concentrations (1.1±0.3 vs. 1.0±0.2 mmol/L, P<0.05). CASR SNPs were not significant determinants for aortic or coronary artery calcification, and were not associated with cardiovascular outcomes or mortality in this RTR cohort. Conclusions Common CASR SNPs may be independent predictors of serum glucose and phosphate concentrations, but are not determinants of vascular calcification or cardiovascular outcomes. PMID:25786244

  15. Effects of elevated CO2 concentrations on denitrifying and nitrifying popualtions at terrestrial CO2 leakeage analogous sites

    NASA Astrophysics Data System (ADS)

    Christine, Dictor Marie; Catherine, Joulian; Valerie, Laperche; Stephanie, Coulon; Dominique, Breeze

    2010-05-01

    CO2 capture and geological storage (CCS) is recognized to be an important option for carbon abatement in Europe. One of the risks of CCS is the leakage from storage site. A laboratory was conducted on soil samples sampled near-surface from a CO2 leakage analogous site (Latera, Italy) in order to evaluate the impact of an elevated soil CO2 concentration on terrestrial bacterial ecosystems form near surface terrestrial environments and to determine a potential bacterial indicator of CO2 leakage from storage site. Surveys were conducted along a 50m long transect across the vent centre, providing a spectrum of CO2 flux rates, soil gas concentrations and compositions (Beaubien et al., 2007). A bacterial diversity studies, performed by CE-SSCP technique, on a soil profile with increasing CO2 soil concentrations (from 0.3% to 100%) showed that a change on bacterial diversity was noted when CO2 concentration was above 50 % of CO2. From this result, 3 soil samples were taken at 70 cm depth in 3 distinct zones (background soil CO2 content, soil CO2 content of 20% and soil CO2 content of 50%). Then theses soil samples were incubated under closed jars flushed with different air atmospheres (20, 50 and 90 % of CO2) during 18 months. At initial, 3, 6, 12 and 18 months, some soil samples were collected in order to estimate the denitrifying, nitrifying activities as a function of CO2 concentration content and times. Theses enzymatic activities were chosen because one occurs under anaerobic conditions (denitrification) and the other occurs under aerobic conditions (nitrification). Both of them were involved in the nitrogen cycle and are major actors of soil function and groundwater quality preservation. Metabolic diversity using BIOLOG Ecoplates was determined on every soil samples. Physico-chemical parameters (e.g. pH, bulk chemistry, mineralogy) were analyzed to have some information about the evolution of the soil during the incubation with increasing soil CO2 concentrations

  16. Effects of landscape heterogeneity on the elevated trace metal concentrations in agricultural soils at multiple scales in the Pearl River Delta, South China.

    PubMed

    Li, Cheng; Li, Fangbai; Wu, Zhifeng; Cheng, Jiong

    2015-11-01

    Based on multiple geo-accumulation indices and correlation and partial redundancy analyses, we examined the spatial patterns of agricultural soil contaminations for As, Pb, Cd, Cr, and Ni in the Pearl River Delta, South China and their relations with landscape heterogeneity at small, medium and large spatial scales. We found that the concentrations of trace elements were slightly elevated, and most trace metals had a geogenic origin. Landscape variables explained 21-53% of the variation of elevated trace metal concentrations with an increasing explanatory power from the small to the large scale. The three variable groups representing parent materials, distance density characteristics and land use had different contributions to the elevated trace metals among scales. Both the distance density variables and land use pattern had a stronger influences on trace metal concentrations at a small scale than at a larger scale, while the parent materials was important at all the scales. PMID:26196316

  17. Effects of elevated carbon dioxide concentrations on survivorship in zebra mussels (Dreissena polymorpha) and Asian clams (Corbicula fluminea)

    SciTech Connect

    McMahon, R.F.; Matthews, M.A.; Shaffer, L.R.; Johnson, P.D.

    1995-06-01

    In order to determine their tolerance to elevated concentrations of carbon dioxide, Asian clams and zebra mussels were collected. Subsamples of both species were acclimated to 25{degrees}C>14 days and then exposed in water at 25{degrees}C to various concentrations of CO{sub 2} and survivorship recorded. Zebra mussels were allowed to byssally attach prior to testing. Media CO{sub 2} concentrations were maintained by continuous bubbling with appropriate gas mixtures. Gas treatment included: (1) anoxia; (2) hypercapnic anoxia; and (3) hypercapnic normoxia. Deaths were recorded in subsamples of both species every 12-24 h until 100% mortality was achieved. No significant mortality occurred among specimens of either species in air bubbled control media in any experiment. Mortality time of zebra mussels exposed to anoxia under 100% N{sub 2} was 103.7 h and of Asian clams, 349.7 h. Mortality was more rapid among samples of both species exposed to anoxia under 100% CO{sub 2}, mean time to death being 43.6 h for zebra mussels and 46.3 h for Asian clams. There was no difference in the survivorship of samples of either species under atmospheres of either 5% CO{sub 2} and 95% N{sub 2} or 100% N{sub 2}, however, Asian clams survived anoxia under either atmosphere 4 to 5 times longer than did zebra mussels. There was no significant mortality among Asian clam or zebra mussel samples after a 39 day exposure to hypercapnic normoxia. While exposure to hypercapnic normoxia under an atmosphere of 5% CO{sub 2}:19% O{sub 2}:76% N{sub 2} did not induce mortality in zebra mussel samples, it completely suppressed all byssal thread production after 7 days of exposure and induced all sampled individuals to release from their byssal attachments within 10 days of exposure. These results indicate that CO{sub 2} injection may be an easily applied, cost-effective, environmentally acceptable molluscicide for mitigation and control of raw water system macrofouling by Asian clams and zebra mussels.

  18. LASER APPLICATIONS IN MEDICINE: Effect of glucose concentration in a model light-scattering suspension on propagation of ultrashort laser pulses

    NASA Astrophysics Data System (ADS)

    Popov, A. P.; Priezzhev, A. V.; Myllylä, Risto

    2005-11-01

    The propagation of laser pulses in the 2% aqueous solution of intralipid — a suspension of lipid particles with optical properties close to those of the human skin, is numerically simulated at different glucose concentrations. The temporal profiles of 820-nm laser pulses diffusely backscattered from a flat, 2-mm thick solution layer are simulated. The laser pulse profiles are detected by fibreoptic detectors of diameter 0.3 mm with the numerical apertures 0.19, 0.29, and 0.39. It is shown that this method can be used to detect changes in the glucose level in the physiological concentration range (100-500 mg dL-1) by monitoring variations in the peak intensity and area of the laser pulse temporal profile (pulse energy).

  19. Source apportionment of elevated BaP concentrations in PM10 aerosols in an alpine valley in Austria

    NASA Astrophysics Data System (ADS)

    Bauer, Heidi; Puxbaum, Hans; Jankowski, Nicole; Sampaio Cordeiro Wagner, Lylian

    2010-05-01

    INTRODUCTION: In a village situated at 1215 m a.s.l. in a natural preserve in an Austrian alpine valley elevated BaP concentrations have been measured in the last years. A highly frequented highway leading from Italy to Germany passes near the village. Monthly means of particulate BaP concentrations show a clear seasonal trend with values below 1 ng/m³ during the warmer months and with concentrations up to 9 ng/m³ in the cold season. Annual averages in the years 2000 - 2005 ranged between 1.4 and 2.8 ng/m³ - much higher than the EU target value of 1 ng/m³. We used a macrotracer model developed at the Vienna University of Technology to determine the contributions of the sources for BaP emissions, which were mainly space heating with wood and traffic from the highway. EXPERIMENTAL: The macrotracer concept is a nine component model to derive source contribution and explains 80-100% of PM10 aerosols in Austria. The amount of traffic exhaust is derived by using EC as tracer, whereas EC produced by wood burning is subtracted, the amount of wood smoke is derived by the anhydro-sugar levoglucosan and the ratio between the anhydro-sugars levoglucosan and mannosan. For the source apportionment of BaP the applied factors reflect on the one hand the composition of the automotive fleet in Austria and on the other hand the composition of the fire wood in the region. Filter samples collected with a high volume sampler in winter were analyzed for PM10 aerosol mass, total, organic, elemental and carbonate carbon, HULIS, anhydro-sugars, polyols and ions (major ions and organic acids) and PAHs. In the same way emission samples taken at a motor test stand and at a test stand for wood combustion were analyzed (Schmidl et al. 2008). The saccharides were determined using high pH anion exchange and pulsed amperometry (HPAE-PAD). Details of the analytical method are given in Iinuma et al., 2009. Elemental and organic carbon were determined with a thermal-optical instrument (Sunset lab

  20. Comparison of a human portable glucometer and an automated chemistry analyzer for measurement of blood glucose concentration in pet ferrets (Mustela putorius furo)

    PubMed Central

    Summa, Noémie M.; Eshar, David; Lee-Chow, Bridget; Larrat, Sylvain; Brown, Dorothy C.

    2014-01-01

    This study compared blood glucose concentrations measured with a portable blood glucometer and a validated laboratory analyzer in venous blood samples of 20 pet ferrets (Mustela putorius furo). Correlation and agreement were evaluated with a Bland-Altman plot method and Lin’s concordance correlation coefficient. Blood glucose concentrations measured with the laboratory analyzer and the glucometer ranged from 1.9 to 8.6 mmol/L and from 0.9 to 9.2 mmol/L, respectively. The glucometer had a poor agreement and correlation with the laboratory analyzer (bias, −0.13 mmol/L; level of agreement, −2.0 to 3.6 mmol/L, concordance correlation coefficient 0.665). The relative sensitivity and specificity of the portable blood glucometer for detection of hypoglycemia were 100% (95% CI: 66% to 100%) and 50% (95% CI: 20% to 80%), respectively. Positive and negative predictive values were 67% (95% CI: 39% to 87%) and 100% (95% CI: 46% to 100%), respectively. Based on these results, clinicians are advised to be cautious when considering the results from this handheld glucometer in pet ferrets, and blood glucose concentrations should be determined with a laboratory analyzer validated for this species. PMID:25183894

  1. Effect of housefly maggot meal (magmeal) diets on the performance, concentration of plasma glucose, cortisol and blood characteristics of Oreochromis niloticus fingerlings.

    PubMed

    Ogunji, J O; Kloas, W; Wirth, M; Neumann, N; Pietsch, C

    2008-08-01

    A 56-day feeding trial was conducted to access the effect of housefly maggot meal (magmeal) diets on the performance, concentration of plasma glucose, cortisol and blood characteristics of Oreochromis niloticus fingerlings. Seven feeds formulated to contain 36% protein and 20 kJ g(-1) gross energy (dry matter basis), were prepared by replacing fish meal with magmeal. Fifteen fingerlings (initial average weight 2.0 +/- 0.1 g) stocked per experimental tank were fed in triplicates at 5% body weight in two portions per day (a level previously established). Growth and food conversion ratio were adequate and comparable without any significant differences (p < 0.5) between feeding groups. Mean values for haematocrit and plasma glucose were not significantly different (p < 0.05) among the feeding groups. Fish group fed control diet (containing highest inclusion level of fish meal and without magmeal) gave the lowest haemoglobin concentration (5.96 +/- 0.22 g dl(-1)). This value was significantly different from other feeding groups. Stressful conditions in fish and in mammals are associated with decreased growth, haematocrit (packed cell volume) and haemoglobin values, increased whole blood glucose (hyperglycaemia) and plasma cortisol concentrations. No such physiological changes were observed in this study. Results suggest that feeding O. niloticus fingerling with magmeal diets did not cause any form of physiological stress. Magmeal can be used as a good alternative protein source in tilapia diets. PMID:18662361

  2. Effects of high and moderate non-structural carbohydrate hay on insulin, glucose, triglyceride, and leptin concentrations in overweight Arabian geldings.

    PubMed

    Shepherd, M L; Pleasant, R S; Crisman, M V; Werre, S R; Milton, S C; Swecker, W S

    2012-06-01

    The objective of this study was to determine the effects of high and moderate non-structural carbohydrates (NSC) hay on insulin, glucose, triglyceride, and leptin concentrations in overweight Arabian geldings. Eight adult overweight (average BCS 7 [9-point scale]) Arabian geldings were fed each of two orchardgrass hays, high NSC (18% DM) and moderate NSC (12% DM), in a cross over design during two 28-day periods. Body weight and body condition score assessment along with blood sampling to measure insulin, glucose, leptin, and triglyceride concentrations were performed on days 0, 7, 14, 21 and 28 of each period. Effects of hay, period, day, and day*hay on plasma glucose and serum leptin were not detected. Serum insulin was influenced by hay (p = 0.001), day (p = 0.03), and day*hay (p = 0.04). Insulin concentrations were higher on day 7 in the high NSC group (15.6 μIU/ml) than the moderate NSC group (9.5 μIU/ml), but not by day 14 (p = 0.0007). Plasma triglyceride was influenced by period (p = 0.0003), day*period (p < 0.0001), and day*hay (p = 0.02). Hyperinsulinaemia was not observed in the overweight Arabian geldings fed either a moderate or high NSC hay. PMID:21575079

  3. Comparison of a human portable glucometer and an automated chemistry analyzer for measurement of blood glucose concentration in pet ferrets (Mustela putorius furo).

    PubMed

    Summa, Noémie M; Eshar, David; Lee-Chow, Bridget; Larrat, Sylvain; Brown, Dorothy C

    2014-09-01

    This study compared blood glucose concentrations measured with a portable blood glucometer and a validated laboratory analyzer in venous blood samples of 20 pet ferrets (Mustela putorius furo). Correlation and agreement were evaluated with a Bland-Altman plot method and Lin's concordance correlation coefficient. Blood glucose concentrations measured with the laboratory analyzer and the glucometer ranged from 1.9 to 8.6 mmol/L and from 0.9 to 9.2 mmol/L, respectively. The glucometer had a poor agreement and correlation with the laboratory analyzer (bias, -0.13 mmol/L; level of agreement, -2.0 to 3.6 mmol/L, concordance correlation coefficient 0.665). The relative sensitivity and specificity of the portable blood glucometer for detection of hypoglycemia were 100% (95% CI: 66% to 100%) and 50% (95% CI: 20% to 80%), respectively. Positive and negative predictive values were 67% (95% CI: 39% to 87%) and 100% (95% CI: 46% to 100%), respectively. Based on these results, clinicians are advised to be cautious when considering the results from this handheld glucometer in pet ferrets, and blood glucose concentrations should be determined with a laboratory analyzer validated for this species. PMID:25183894

  4. Direct measurements of blood glucose concentration in the presence of saccharide interferences using slope and bias orthogonal signal correction and Fourier transform near-infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Abookasis, David; Workman, Jerome J.

    2011-02-01

    Saccharide interferences such as Dextran, Galactose, etc. have a great potential to interfere with near infrared (NIR) glucose analysis since they have a similar spectroscopic fingerprint and are present physiologically at large relative concentrations. These can lead to grossly inappropriate interpretation of patient glucose levels and resultant treatment in critical care and hospital settings. This study describes a methodology to reduce this effect on glucose analysis using an NIR Fourier transform spectroscopy method combined with a multivariate calibration technique (PLS) using preprocessing by orthogonal signal correction (OSC). A mathematical approach based on the use of a single calibration based bias and slope correction was applied in addition to a standard OSC was investigated. This approach is combined with a factorial interferent calibration design to accommodate for interference effects. We named this approach as a slope and bias OSC (sbOSC). sbOSC differs from OSC in the way it handles the prediction. In sbOSC, statistics on slope and bias obtained from a set of calibration samples are then used as a validation parameter in the prediction set. Healthy human volunteer blood with different glucose (80 to 200 mg/dL) and hematocrit (24 to 48 vol.%) levels containing high expected levels of inteferents have been measured with a transmittance near-infrared Fourier transform spectrometer operates in the broadband spectral range of 1.25-2.5 μm (4000-8000 cm-1). The effect of six interferents compounds used in intensive care and operating rooms, namely Dextran, Fructose, Galactose, Maltose, Mannitol, and Xylose, were tested on blood glucose. A maximum interference effect (MIE) parameter was used to rank the significance for the individual interferent type on measurement error relative to the total NIR whole blood glucose measurement error. For comparison, a YSI (Yellow Springs Instrument) laboratory reference glucose analyzer and NIR data were collected at

  5. Use of ceftaroline after glycopeptide failure to eradicate meticillin-resistant Staphylococcus aureus bacteraemia with elevated vancomycin minimum inhibitory concentrations.

    PubMed

    Paladino, Joseph A; Jacobs, David M; Shields, Ryan K; Taylor, Jerusha; Bader, Justin; Adelman, Martin H; Wilton, Greg J; Crane, John K; Schentag, Jerome J

    2014-12-01

    Elevated minimum inhibitory concentrations (MICs) of vancomycin against meticillin-resistant Staphylococcus aureus (MRSA) and the emergence of heteroresistant S. aureus strains have led to increased use of anti-MRSA antibiotics other than vancomycin. Ceftaroline fosamil is a novel cephalosporin with activity against MRSA, but there are limited clinical data on its use for MRSA bacteraemia (MRSAB) and against strains exhibiting high vancomycin MICs (2-4 μg/mL). This multicentre, retrospective, case-control study compared the microbiological and clinical effectiveness of ceftaroline used after vancomycin failure with that of vancomycin-treated controls for the treatment of MRSA with vancomycin MICs ≥ 2 μg/mL. In total, 32 patients were matched 1:1 with respect to vancomycin MIC, age and origin of bacteraemia. In the ceftaroline group, patients received prior MRSA therapy for a median of 5 days [interquartile range (IQR), 3-15.8 days] prior to switching to ceftaroline. Median time to eradication of MRSA was significantly less after treatment with ceftaroline compared with vancomycin [4 days (IQR, 3-7.5 days) vs. 8 days (IQR, 5.8-19.5 days); P=0.02]. Both clinical success at the end of treatment and recurrence of MRSA at Day 7 were trending towards being inferior in the vancomycin group, although the results did not attain statistical significance [81% vs. 44% (P=0.06) and 6% vs. 38% (P=0.08), respectively]. Ceftaroline added at the point of vancomycin failure resolves MRSAB more rapidly and with a higher rate of clinical success, therefore ceftaroline should be considered as an alternative for these difficult-to-treat infections. PMID:25282169

  6. Biosensor based on excessively tilted fiber grating in thin-cladding optical fiber for sensitive and selective detection of low glucose concentration.

    PubMed

    Luo, Binbin; Yan, Zhijun; Sun, Zhongyuan; Liu, Yong; Zhao, Mingfu; Zhang, Lin

    2015-12-14

    We report a highly sensitive, high Q-factor, label free and selective glucose sensor by using excessively tilted fiber grating (Ex-TFG) inscribed in the thin-cladding optical fiber (TCOF). Glucose oxidase (GOD) was covalently immobilized on optical fiber surface and the effectiveness of GOD immobilization was investigated by the fluorescence microscopy and highly accurate spectral interrogation method. In contrast to the long period grating (LPG) and optical fiber (OF) surface Plasmon resonance (SPR) based glucose sensors, the Ex-TFG configuration has merits of nearly independent cross sensitivity of the environmental temperature, simple fabrication method (no noble metal deposition or cladding etching) and high detection accuracy (or Q-factor). Our experimental results have shown that Ex-TFG in TCOF based sensor has a reliable and fast detection for the glucose concentration as low as 0.1~2.5mg/ml and a high sensitivity of ~1.514 nm·(mg/ml)⁻¹, which the detection accuracy is ~0.2857 nm⁻¹ at pH 5.2, and the limit of detection (LOD) is 0.013~0.02 mg/ml at the pH range of 5.2~7.4 by using an optical spectrum analyzer with a resolution of 0.02 nm. PMID:26699032

  7. Greater antioxidant and respiratory metabolism in field-grown soybean exposed to elevated O3 under both ambient and elevated CO2 concentrations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antioxidant metabolism is responsive to oxidative signals associated with fluctuating environmental conditions, and is proposed to be a key component of ozone (O3) tolerance in plants. Tropospheric O3 concentration ([O3]) has approximately doubled since the Industrial Revolution and is expected to i...

  8. Identification of quantitative trait loci associated with fructose, glucose and sucrose concentration in snap bean (Phaseolus Vulgaris L.) pods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sugars, including fructose, glucose, and sucrose contribute significantly to the flavor and consumer acceptance of snap beans (Phaseolus vulgaris L.). Differences between dry and snap bean cultivars and among snap bean cultivars in the patterns of accumulation of sugars have been observed. In ‘Eagle...

  9. Influence of excessive dietary protein intake during late gestation on drylot beef cow performance and progeny growth, carcass characteristics, and plasma glucose and insulin concentrations.

    PubMed

    Wilson, T B; Long, N M; Faulkner, D B; Shike, D W

    2016-05-01

    Spring-calving cows ( = 49) were used to investigate the effects of excessive prepartum dietary protein intake on late gestation cow performance as well as subsequent progeny growth, carcass characteristics, and plasma glucose and insulin concentrations. Treatments were formulated to be isocaloric and provide 100% (REQ) or 129% (HP) of CP requirement. Treatments were limit-fed 78 ± 12 d prepartum to calving. All cows were fed a common diet postpartum. Cow BW and BCS were recorded at initiation of treatments and within 48 h post-calving. Milk production was estimated via the weigh-suckle-weigh technique 69 ± 11 d postpartum. Calf BW was measured at birth and at weaning (121 ± 11 d of age). Progeny ( = 42) were weaned as a group and placed into a feedlot and fed a common finishing diet. Glucose and insulin concentrations were analyzed on a subset of progeny (12 per treatment) 90, 120, 150, 180, 210, and 240 min post-feeding, 2 d before slaughter (342 ± 11 d of age). Treatment had no effect ( ≥ 0.22) on cow BW, BCS, milk production, and subsequent reproduction or progeny preweaning growth. Progeny finishing growth and marbling scores were not affected ( ≥ 0.24) by treatment, yet 12th rib fat thickness ( < 0.01), KPH ( = 0.04), and YG ( = 0.01) were greater for progeny born to HP dams. Progeny born to HP dams had decreased ( ≤ 0.01) glucose and insulin concentrations, and insulin to glucose ratios, indicating greater insulin sensitivity. Although feeding cows 129% of CP requirement during late gestation did not affect cow performance or progeny preweaning or finishing period growth; carcass adiposity was increased by maternal treatment. PMID:27285701

  10. Common Missense Variant in the Glucokinase Regulatory Protein Gene Is Associated With Increased Plasma Triglyceride and C-Reactive Protein but Lower Fasting Glucose Concentrations

    PubMed Central

    Orho-Melander, Marju; Melander, Olle; Guiducci, Candace; Perez-Martinez, Pablo; Corella, Dolores; Roos, Charlotta; Tewhey, Ryan; Rieder, Mark J.; Hall, Jennifer; Abecasis, Goncalo; Tai, E. Shyong; Welch, Cullan; Arnett, Donna K.; Lyssenko, Valeriya; Lindholm, Eero; Saxena, Richa; de Bakker, Paul I.W.; Burtt, Noel; Voight, Benjamin F.; Hirschhorn, Joel N.; Tucker, Katherine L.; Hedner, Thomas; Tuomi, Tiinamaija; Isomaa, Bo; Eriksson, Karl-Fredrik; Taskinen, Marja-Riitta; Wahlstrand, Björn; Hughes, Thomas E.; Parnell, Laurence D.; Lai, Chao-Qiang; Berglund, Göran; Peltonen, Leena; Vartiainen, Erkki; Jousilahti, Pekka; Havulinna, Aki S.; Salomaa, Veikko; Nilsson, Peter; Groop, Leif; Altshuler, David; Ordovas, Jose M.; Kathiresan, Sekar

    2008-01-01

    OBJECTIVE—Using the genome-wide association approach, we recently identified the glucokinase regulatory protein gene (GCKR, rs780094) region as a novel quantitative trait locus for plasma triglyceride concentration in Europeans. Here, we sought to study the association of GCKR variants with metabolic phenotypes, including measures of glucose homeostasis, to evaluate the GCKR locus in samples of non-European ancestry and to fine- map across the associated genomic interval. RESEARCH DESIGN AND METHODS—We performed association studies in 12 independent cohorts comprising >45,000 individuals representing several ancestral groups (whites from Northern and Southern Europe, whites from the U.S., African Americans from the U.S., Hispanics of Caribbean origin, and Chinese, Malays, and Asian Indians from Singapore). We conducted genetic fine-mapping across the ∼417-kb region of linkage disequilibrium spanning GCKR and 16 other genes on chromosome 2p23 by imputing untyped HapMap single nucleotide polymorphisms (SNPs) and genotyping 104 SNPs across the associated genomic interval. RESULTS—We provide comprehensive evidence that GCKR rs780094 is associated with opposite effects on fasting plasma triglyceride (Pmeta = 3 × 10−56) and glucose (Pmeta = 1 × 10−13) concentrations. In addition, we confirmed recent reports that the same SNP is associated with C-reactive protein (CRP) level (P = 5 × 10−5). Both fine-mapping approaches revealed a common missense GCKR variant (rs1260326, Pro446Leu, 34% frequency, r2 = 0.93 with rs780094) as the strongest association signal in the region. CONCLUSIONS—These findings point to a molecular mechanism in humans by which higher triglycerides and CRP can be coupled with lower plasma glucose concentrations and position GCKR in central pathways regulating both hepatic triglyceride and glucose metabolism. PMID:18678614

  11. Short communication: Effects of dairy calf hutch elevation on heat reduction, carbon dioxide concentration, air circulation, and respiratory rates.

    PubMed

    Moore, D A; Duprau, J L; Wenz, J R

    2012-07-01

    Heat stress affects dairy calf welfare and can result in morbidity, mortality, and lower weight gain. The purpose of this project was to evaluate the effects of elevating the back of plastic calf hutches on measures of ventilation and heat stress. A total of 15 calves housed in individual hutches were enrolled, with each calf hutch serving as its own control. Heat, humidity, carbon dioxide, and wind speed were measured inside each hutch and the observations were compared with external measurements over two 24-h periods; 1 period without and 1 with hutch elevation. Respiratory rates were measured in the morning and afternoon as an indicator of the degree of heat stress experienced by calves with and without elevation of the hutch. When the hutch was elevated, internal hutch temperatures were cooler than external temperatures, hutch carbon dioxide levels were lower and respiratory rates were lower, particularly comparing the afternoon observation periods. PMID:22720960

  12. Brain glucose metabolism in an animal model of depression.

    PubMed

    Detka, J; Kurek, A; Kucharczyk, M; Głombik, K; Basta-Kaim, A; Kubera, M; Lasoń, W; Budziszewska, B

    2015-06-01

    An increasing number of data support the involvement of disturbances in glucose metabolism in the pathogenesis of depression. We previously reported that glucose and glycogen concentrations in brain structures important for depression are higher in a prenatal stress model of depression when compared with control animals. A marked rise in the concentrations of these carbohydrates and glucose transporters were evident in prenatally stressed animals subjected to acute stress and glucose loading in adulthood. To determine whether elevated levels of brain glucose are associated with a change in its metabolism in this model, we assessed key glycolytic enzymes (hexokinase, phosphofructokinase and pyruvate kinase), products of glycolysis, i.e., pyruvate and lactate, and two selected enzymes of the tricarboxylic acid cycle (pyruvate dehydrogenase and α-ketoglutarate dehydrogenase) in the hippocampus and frontal cortex. Additionally, we assessed glucose-6-phosphate dehydrogenase activity, a key enzyme in the pentose phosphate pathway (PPP). Prenatal stress increased the levels of phosphofructokinase, an important glycolytic enzyme, in the hippocampus and frontal cortex. However, prenatal stress had no effect on hexokinase or pyruvate kinase levels. The lactate concentration was elevated in prenatally stressed rats in the frontal cortex, and pyruvate levels remained unchanged. Among the tricarboxylic acid cycle enzymes, prenatal stress decreased the level of pyruvate dehydrogenase in the hippocampus, but it had no effect on α-ketoglutarate dehydrogenase. Like in the case of glucose and its transporters, also in the present study, differences in markers of glucose metabolism between control animals and those subjected to prenatal stress were not observed under basal conditions but in rats subjected to acute stress and glucose load in adulthood. Glucose-6-phosphate dehydrogenase activity was not reduced by prenatal stress but was found to be even higher in animals exposed to

  13. Effects of elevated partial pressure of carbon dioxide and season of the year on forage quality and cyanide concentration of Trifolium repens L. from a FACE experiment

    NASA Astrophysics Data System (ADS)

    Frehner, Marco; Lüscher, Andreas; Hebeisen, Thomas; Zanetti, Silvia; Schubiger, Franz; Scalet, Mario

    Differently managed (cutting frequency and N fertilization) Trifolium repens monocultures were grown at 60 Pa and 35 Pa of pCO 2 (partial pressure of CO 2) in a Free Air Carbon dioxide Enrichment (FACE) array. The concentrations of cyanide, digestible organic matter, crude protein and net energy for lactation were measured at different harvests throughout the growing season. The average cyanide concentrations differed significantly in the years and the seasons within the year; however, the concentrations were not affected by CO 2. Digestible organic matter, crude protein and net energy for lactation differed significantly with the seasons of the year and cutting frequencies. While digestible organic matter and net energy for lactation were not affected by elevated pCO 2, the concentration of crude protein decreased from 288 g kg -1 at ambient to 251 g kg -1 at elevated pCO 2. Since the crude protein concentration in herbage from Trifolium monocultures was very high even at elevated CO 2, it is suggested that this decrease in crude protein concentration does not negatively affect forage quality. We conclude that, in Trifolium herbage, the seasons of the year and management practices are more decisive for forage quality than changes in pCO 2. We shall discuss how forage quality and cyanide intake by ruminants may, however, be affected by CO 2-induced shifts in the proportion of species in mixed plant communities.

  14. The effect of subambient to elevated atmospheric CO₂ concentration on vascular function in Helianthus annuus: implications for plant response to climate change.

    PubMed

    Rico, Christopher; Pittermann, Jarmila; Polley, H Wayne; Aspinwall, Michael J; Fay, Phillip A

    2013-09-01

    Plant gas exchange is regulated by stomata, which coordinate leaf-level water loss with xylem transport. Stomatal opening responds to internal concentrations of CO₂ in the leaf, but changing CO₂ can also lead to changes in stomatal density that influence transpiration. Given that stomatal conductance increases under subambient concentrations of CO₂ and, conversely, that plants lose less water at elevated concentrations, can downstream effects of atmospheric CO₂ be observed in xylem tissue? We approached this problem by evaluating leaf stomatal density, xylem transport, xylem anatomy and resistance to cavitation in Helianthus annuus plants grown under three CO₂ regimes ranging from pre-industrial to elevated concentrations. Xylem transport, conduit size and stomatal density all increased at 290 ppm relative to ambient and elevated CO₂ concentrations. The shoots of the 290-ppm-grown plants were most vulnerable to cavitation, whereas xylem cavitation resistance did not differ in 390- and 480-ppm-grown plants. Our data indicate that, even as an indirect driver of water loss, CO₂ can affect xylem structure and water transport by coupling stomatal and xylem hydraulic functions during plant development. This plastic response has implications for plant water use under variable concentrations of CO₂, as well as the evolution of efficient xylem transport. PMID:23731256

  15. Effect of dietary supplementation of n-3 fatty acids and elevated concentrations of dietary protein on the performance of sows.

    PubMed

    Mateo, R D; Carroll, J A; Hyun, Y; Smith, S; Kim, S W

    2009-03-01

    A study was conducted to determine the effect of dietary supplementation of n-3 fatty acids (O3FA) with or without elevated concentrations of protein on the performance of sows during the first and the subsequent parity. Sixty-four pregnant gilts with BW of 195.0 +/- 2.1 kg and backfat (BF) thickness of 12.9 +/- 0.2 mm were assigned to 4 dietary treatments from d 60 of gestation (late gestation) to d 21 of lactation. Dietary treatments were 1) a control diet; 2) a high-protein diet (HP); 3) the control diet + 0.2% O3FA (O3); and 4) the HP diet + 0.2% O3FA (HPO3). For the control and O3 treatments, CP contents were 12.3% for late gestation and 17.9% for lactation, and for the HP and HPO3 treatments, CP contents were 18.4% for late gestation and 19.5% for lactation. On d 60 and 110 of gestation and after farrowing (within 12 h postfarrowing), on d 10 and 21 of lactation, BW, BF thickness, and blood samples were obtained. The total number of piglets and the number of piglets born alive and their birth weights were measured within 12 h postfarrowing. Colostrum and milk samples were obtained on d 2 and 21 of lactation, respectively. All piglets were weaned at 21 d. The wean-to-estrus interval and ADFI were recorded. The same measurements were obtained from the control and O3 groups during the subsequent parity. Dietary treatment did not affect BW, BF thickness, ADFI, and the wean-to-estrus interval of sows during their first reproductive cycle. Supplementation of O3FA increased both eicosapentaenoic acid and docosahexaenoic acid contents (P < 0.05) in colostrum and mature milk. First-parity litter size and piglet birth weight did not differ among treatment groups. Piglet BW was greater (P < 0.05) for the O3 group compared with both the control and HPO3 groups at d 10 and 21 of lactation. The same pattern was also noted for overall piglet BW gain. Both piglet and litter characteristics of the HP group did not differ from those of other groups throughout lactation. During

  16. Thresholds of whole-blood β-hydroxybutyrate and glucose concentrations measured with an electronic hand-held device to identify ovine hyperketonemia.

    PubMed

    Pichler, M; Damberger, A; Schwendenwein, I; Gasteiner, J; Drillich, M; Iwersen, M

    2014-03-01

    Metabolic disorders, especially hyperketonemia, are very common in dairy sheep. The whole-blood concentrations of β-hydroxybutyrate (BHBA) and glucose can be determined by commercially available electronic hand-held devices, which are used in human medicine and for the detection of ketosis in dairy cows. The aim of this study was to evaluate the suitability of the hand-held device Precision Xceed (PX; Abbott Diabetes Care Inc., Abbott Park, IL) to detect hyperketonemia in ewes. An additional objective of this study was to evaluate the agreement between samples obtained by minimal invasive venipuncture of an ear vein and measurements of whole-blood samples from the jugular vein (vena jugularis, v. jug.). Blood samples taken from the v. jug. were collected from 358 ewes on 4 different farms. These samples and a blood drop obtained from an ear vein were analyzed simultaneously on farm with the PX. For method comparison, the samples obtained from the v. jug. were also analyzed by standard methods, which served as the gold standard at the Central Laboratory of the University of Veterinary Medicine Vienna, Austria. The correlation coefficients between the serum BHBA concentration and the concentrations measured with the hand-held meter in the whole blood from an ear vein and the v. jug. were 0.94 and 0.96, respectively. The correlation coefficients of plasma and whole-blood glucose concentration were 0.68 for the v. jug. and 0.47 for the ear vein. The mean glucose concentration was significantly lower in animals classified as hyperketonemic (BHBA ≥ 1.6 mmol/L) compared with healthy ewes. Whole-blood concentrations of BHBA and glucose measured with the PX from v. jug. showed a constant negative bias of 0.15 mmol/L and 8.4 mg/dL, respectively. Hence, a receiver operating characteristic analysis was performed to determine thresholds for the PX to detect hyperketonemia in ewes. This resulted in thresholds for moderate ketosis of BHBA concentrations of 0.7 mmol/L in blood

  17. Hyperglycemic glucose concentrations up-regulate the expression of type VI collagen in vitro. Relevance to alterations of peripheral nerves in diabetes mellitus.

    PubMed Central

    Muona, P.; Jaakkola, S.; Zhang, R. Z.; Pan, T. C.; Pelliniemi, L.; Risteli, L.; Chu, M. L.; Uitto, J.; Peltonen, J.

    1993-01-01

    Electron microscopy of peripheral nerves obtained from two diabetic patients revealed large deposits of microfibrils and the presence of Luse bodies in the vicinity of perineurial cells. Microfibrils were found to accumulate also in the sciatic nerves of diabetic BB rats; these microfibrillar deposits were shown to contain type VI collagen by immunoelectron microscopy. Connective tissue cells cultured from rat sciatic nerves were exposed to high glucose concentrations. High glucose concentrations up-regulated the mRNA steady-state levels of alpha 1(VI), alpha 2(VI), and alpha 3(VI) chains of type VI collagen and caused accumulation of type VI collagen-containing fibrils in the cultures. Immunostaining and in situ hybridizations demonstrated that perineurial cells, Schwann cells, and fibroblasts expressed type VI collagen at the mRNA and protein levels. The results suggest that the turnover and supramolecular assembly of type VI collagen are perturbed in diabetic nerves and that glucose per se increases the expression of type VI collagen in vitro. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:8494053

  18. Photosynthesis, productivity, and yield of maize are not affected by open-air elevation of CO2 concentration in the absence of drought.

    PubMed

    Leakey, Andrew D B; Uribelarrea, Martin; Ainsworth, Elizabeth A; Naidu, Shawna L; Rogers, Alistair; Ort, Donald R; Long, Stephen P

    2006-02-01

    While increasing temperatures and altered soil moisture arising from climate change in the next 50 years are projected to decrease yield of food crops, elevated CO2 concentration ([CO2]) is predicted to enhance yield and offset these detrimental factors. However, C4 photosynthesis is usually saturated at current [CO2] and theoretically should not be stimulated under elevated [CO2]. Nevertheless, some controlled environment studies have reported direct stimulation of C4 photosynthesis and productivity, as well as physiological acclimation, under elevated [CO2]. To test if these effects occur in the open air and within the Corn Belt, maize (Zea mays) was grown in ambient [CO2] (376 micromol mol(-1)) and elevated [CO2] (550 micromol mol(-1)) using Free-Air Concentration Enrichment technology. The 2004 season had ideal growing conditions in which the crop did not experience water stress. In the absence of water stress, growth at elevated [CO2] did not stimulate photosynthesis, biomass, or yield. Nor was there any CO2 effect on the activity of key photosynthetic enzymes, or metabolic markers of carbon and nitrogen status. Stomatal conductance was lower (-34%) and soil moisture was higher (up to 31%), consistent with reduced crop water use. The results provide unique field evidence that photosynthesis and production of maize may be unaffected by rising [CO2] in the absence of drought. This suggests that rising [CO2] may not provide the full dividend to North American maize production anticipated in projections of future global food supply. PMID:16407441

  19. Post-earthquake relaxation evidence for laterally variable viscoelastic structure and elevated water concentration in the southwestern California mantle

    NASA Astrophysics Data System (ADS)

    Pollitz, F. F.

    2014-12-01

    I re-examine the lower crust and mantle relaxation following two large events in the Mojave Desert: the 1992 M7.3 Landers and 1999 M7.1 Hector Mine, California, earthquakes. More than a decade of GPS time series from regional sites out to 250 km from the ruptures are used to constrain models of postseismic relaxation. Crustal motions in the Mojave Desert region are elevated for several years following each event, with perturbations from a pre-Landers background of order mm to cm per year. I consider afterslip and relaxation of the ductile lower crust and mantle to explain these motions. To account for broad scale relaxation, the Burgers body model is employed, involving Kelvin (transient) viscosity and rigidity and Maxwell (steady state) viscosity and rigidity. I use the code VISCO2.5D to perform 2.5D modeling of the postseismic relaxation (3D quasi-static motions computed on 2D, laterally heterogeneous viscoelastic structures; Pollitz, 2014 GJI). Joint afterslip / postseismic relaxation modeling of continuous GPS time series up to 10.46 years following the Hector Mine earthquake (i.e. up to the time of the 2010 M7.2 El Mayor-Cucapah earthquake) reveals that a northwest-trending `southwest domain' that envelopes the San Andreas fault system and western Mojave Desert has ~4 times larger Maxwell mantle viscosity than the adjacent `northeast domain' that extends inland and envelopes the Landers and Hector Mine rupture areas in the central Mojave Desert. This pattern is counter to that expected from regional heat flow, which is higher in the northeast domain, but it is explicable by means of a non-linear rheology that includes dependence on both strain rate and water concentration. I infer that the southwest domain mantle has a relatively low steady-state viscosity because of its high strain rate and water content. The relatively low mantle water content of the northeast domain is interpreted to result from the continual extraction of water through igneous and volcanic

  20. In Vivo Blood Glucose Quantification Using Raman Spectroscopy

    PubMed Central

    Shao, Jingwei; Lin, Manman; Li, Yongqing; Li, Xue; Liu, Junxian; Liang, Jianpin; Yao, Huilu

    2012-01-01

    We here propose a novel Raman spectroscopy method that permits the noninvasive measurement of blood glucose concentration. To reduce the effects of the strong background signals produced by surrounding tissue and to obtain the fingerprint Raman lines formed by blood analytes, a laser was focused on the blood in vessels in the skin. The Raman spectra were collected transcutaneously. Characteristic peaks of glucose (1125 cm-1) and hemoglobin (1549 cm-1) were observed. Hemoglobin concentration served as an internal standard, and the ratio of the peaks that appeared at 1125 cm-1 and 1549 cm-1 peaks was used to calculate the concentration of blood glucose. We studied three mouse subjects whose blood glucose levels became elevated over a period of 2 hours using a glucose test assay. During the test, 25 Raman spectra were collected transcutaneously and glucose reference values were provided by a blood glucose meter. Results clearly showed the relationship between Raman intensity and concentration. The release curves were approximately linear with a correlation coefficient of 0.91. This noninvasive methodology may be useful for the study of blood glucose in vivo. PMID:23133555

  1. Gas exchange, biomass, whole-plant water-use efficiency and water uptake of peach (Prunus persica) seedlings in response to elevated carbon dioxide concentration and water availability.

    PubMed

    Centritto, Mauro; Lucas, Maree E; Jarvis, Paul G

    2002-07-01

    We examined the interactive effects of elevated CO2 concentration ([CO2]) and water stress on growth and physiology of 1-year-old peach (Prunus persica L.) seedlings grown in 10-dm3 pots in open-top chambers with ambient (350 micromol mol-1) or elevated (700 micromol mol-1) [CO2]. Seedlings were supplied weekly with a non-limiting nutrient solution. Water was withheld from half of the plants in each treatment for a 4-week drying cycle, to simulate a sudden and severe water stress during the phase of rapid plant growth. Throughout the growing season, seedlings in elevated [CO2] had higher assimilation rates, measured at the growth [CO2], than seedlings in ambient [CO2], and this caused an increase in total dry mass of about 33%. Stomatal conductance, total water uptake, leaf area and leaf number were unaffected by elevated [CO2]. Because seedlings in the two CO2 treatments had similar transpiration despite large differences in total dry mass, water-use efficiency (WUE) of well-watered and water-stressed seedlings grown in elevated [CO2] was an average of 51 and 63% higher, respectively, than WUE of comparable seedlings grown in ambient [CO2]. Elevated [CO2] enhanced total biomass of water-stressed seedlings by 31%, and thus ameliorated the effects of water limitation. However, the percentage increases in total dry mass between well-watered and water-stressed seedlings were similar in ambient (53%) and elevated (58%) [CO2], demonstrating that there was no interaction between elevated [CO2] and water stress. This finding should be considered when predicting responses of trees to global climate change in hot and dry environments, where predicted temperature increases will raise evaporative demands and exacerbate the effects of drought on tree growth. PMID:12091151

  2. Elevated mercury concentrations in soils, sediments, water, and fish of the Madeira River basin, Brazilian Amazon: a function of natural enrichments?

    PubMed

    Lechler, P J; Miller, J R; Lacerda, L D; Vinson, D; Bonzongo, J C; Lyons, W B; W